Hitachi Ex120 Problem

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I had a very similar problem but with my EX60 URG unit. It was a clogged fuel line. Check my posts, might be some good info for ya there from the people that helped me and saved my a lot of time and money.

I got a 120-3 and when the fuel filter plugs it with in hours when you notice it till when she won't even move. Make sure you chwck the pre filter that is screwed in to the bango housing before or on the spin on filter housing.The only other thing I could think of would be the rpm sensor not working but can't see that.I went though this once and I wound up cleaning eveything from the tank back.

spunkeymonkey said:the engine recovers its revs straight away when you release the lever.Click to expand...That little tidbit of info leads me to think it's not a fuel problem. If an engine is slowing/stalling under load from a fuel restriction, when you release the load, the revs will slowly recover. If the revs recover rapidly when load is released, fuel is flowing freely.I've worked on dash 2's, no dash 1 machines. I'm almost certain they have different pumps. It does sound like you have a pump overstroke problem. Do you maybe have a problem with the swash plate angle sensor? Or do your pumps even have one? I don't know how to test them. But I did have a dash 2 with a faulty plate sensor that caused the same symptoms you describe. I removed the plate sensor from another working dash 2, installed it on the problem machine, it was then healed.

Whats the serial number on your machine, also when the engine stalls does the engine black smoke or is the exhaust clear/ no smoke

I made a mistake, it is an EX120-2! There is black smoke from the exhaust as the engine dies, this clears when the revs recover. Where is the swash plate angle sensor located?

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spunkeymonkey said:I made a mistake, it is an EX120-2! There is black smoke from the exhaust as the engine dies, this clears when the revs recover. Where is the swash plate angle sensor located?Click to expand...When you open the right rear door, your staring at the rear of the hyd pump. On the right side of the pump is a round thing with, I think, two wires going to it. That's the angle sensor. You could remove it to check the tab that turns the sensor and the coupler that it seats into, but before you remove it, mark the position of the sensor. It's position is adjustable by loosening the allen head mounting screw and rotating the sensor via screw slot, this is for fine tuning of the angle sensor operation. Like I said, I don't know how to test the sensor, I was lucky and had another working dash 2 right next to it. With your engine loading and blowing black smoke, it does sound like your pump is overstroking. Hope ya find your problem.

I finally found a sensor to try on my machine, but it made no difference! Also now, the machine will not rev up, none of the power setting buttons work.

Sounds like the N sensor is not working, Check wiring to sensor on top of pump also known as the rpm sensor. Looks like a button held in with one bolt.

Ive had time to have a mess with the digger today! I have got the buttons to work to rev it up, it was a bad connection in the cab. The machine is slightly better than it was, but it still stalls. It is as though everything is running too fast, and the engine cant keep up. There is a tortoise-hare button, but nothing seems to happen if you press it. The leds work though. Is this just for the tracking, or all the hydraulics? Could it be a bad wire somewhere making everything too fast? Also, when I had the pump off in the beginning, the coupling between the pump and the engine was all chewed up. Could this cause any symptoms? Thanks in advance for any help!

Tortoise Hare button is only for travel speed, check for more wiring issues in cab for other problems as well, it sounds like your pump is going to full swash and staying there. This is an indication that the pump displacement solenoids are not working properly, check all fuses and make sure they are the proper rating, two of those fuses are for pump displacement solenoids. Also check that the wiring to the solenoids is good and also the wireing to the angle sensor is good. Has anyone been messing with the angle sensor? Looks like a small top hat on the right side of the pump.

If you had the angle sensor out you may have put it back in in the wrong orientation, there is a small dot on the shaft and when you put it back in the dot must face away from the harness side. You then must set the sensor to the proper voltage, I can explain that later as it is a bit complicated, make sure the orientation is correct first then try it and see if it is somewhat better.

Ive checked all the wiring, and checked that the dot on the shaft is facing away from the wiring. Now you can explain about setting the voltage on the sensor!

I have sent you an email with the page from the manual to set the voltage. Let me know how it works.

You, Sir, are a true gentleman! Thank you very much. I shall try that tomorrow morning. Were these dash 2 excavators supplied new in Canada?

Yes and also many gry market machines were imported.

I have carried out the procedure you emailed me. The machine is no different! Any other ideas?

:canada Take out the angle sensor and put a flat blade screwdriver into the slot were the angle sensor goes and try to easily turn the shaft that is in there. It should only turn very little if it turns easy then let me know. You should not be able to turn it more than about the width of a hair.

Is the machine good when you first start it and within 3 minuets it is smoking and stalling under load?

I havent tried putting a screwdriver into the sensor slot yet, will do tomorrow morning. The machine smokes and stalls from cold.

Another thing you can try is to swap the electrical plugs on the pump displacement solenoids on the back of the hyd. pump. If the problem goes the opposite way (everything super slow and no engine pull down) then you have a bad solenoid.

Hi, I'm Tom from Ontatio, Canada. Did you find the problem with your ex120 stalling when under load (or cutting out) ? I have the exact problem with mine but it only happens once the machine is hot. When its cold it runs fine.

Did you and spunkeymonkey solve the hitachi ex120 hydrolic stall problem, I have the same problem only when the machine gets hot?Tom

Tom have you checked your fuel screen in the banjo fitting? I haven't heard weather spunkeymonkey fixed his problem.

yes, the banjo fuel screen was clean and I .also replaced the fuel filter, but its still the same problem. any other ideas?

If it is only doing it when hot it may be one of the pump displacement solenoids starting to break down electrically, what you can do is swap places with the two solenoids and see if the problem goes the other way and the machine becomes very slow when hot.they are held onto the pump with 4 allen head bolts, just unplug and change places and plug back in and give it a try.:canada

Tom what machine do you have ? An EX120-1 ,2 , 3, or 5.?

I'm not sure, how do I find out?

I just checked the machine and its a ex120-2

Here is a breakdown of your pump, the two solenoids are up on top, release the pressure in the hyd tank before you swap them.

HmmVery interesting Can anyone help me find a manual for teh 120-2?

I can supply you with one if you are interested. Just PM me.

I narrowed down the problem with the ex120-2 cutting out when hot. It was the displacement solenoid valve, The electrical coil was crack and that was because the two oil seals behind the coil leaked and would slowly preasurize the electrical coil and expand it, then cutting out the coil circuit ( the coil is 18 ohms resistance) then the excavator would start to cut out. I fixed the seals and now its OK, but I would still like to replace the coil or solenoid. Does anyone have one ?

-3Doc. How much do you want for the ex120-2 manual?from[email protected]

I have a JD 490E excavator, the engine stalls whenever i put load on the hydraulic functions, tested the wire to the displacement solenoid and no current, also testing this wire shows the - (negative) is not grounded, no continuity with grounds. so it seems i have a current problem, if so , is it the computer that controls these solenoids. what to do? plz help.

also i disconnected the solenoids and tested them they are both working , but when connected on the excavator no current is going to them. i took off the connector and connected one directly to the battery via a long wire, and the machine moved very slowly but did not stall, however when i connected both of them to the battery the machine stalled as before.

andre01 said:I have a JD 490E excavator, the engine stalls whenever i put load on the hydraulic functions, .........plz help.Click to expand...Now you have 3 posts you can start a new thread.Having a quick scan down the thread titles should give you some idea what to use as a title to get the help you need.eg, JD 490E stalling under load. Advice please.Copy and paste what you have already done and discovered here and see how it goes.

andre01 said:also i disconnected the solenoids and tested them they are both working , but when connected on the excavator no current is going to them. i took off the connector and connected one directly to the battery via a long wire, and the machine moved very slowly but did not stall, however when i connected both of them to the battery the machine stalled as before.Click to expand...With the key on and engine not running you should have 24volts to one wire on each of the displacement solenoids, (the ground is controled by the computer and you can not check this easily.) If you don't have 24 volts to each solenoid then you can check the fuses first there is a one amp fuse for each in the fuse box. Make sure they are good then go from there and check the wiring from the fuse box back to the solenoids. Hope this helps.:canada

Worth checking it outEvery pump has solenoid or what they call proportional valve that make your pump to de stroke (since you said you have black smoke and then recover) so connection to PPV (inside or behind you’ll have check valve, it has to move freely) are very important and if you have some twisted connections(new wire harness) each connection will loses connectivity so eliminate that...Good luck

-3Doc said:I can supply you with one if you are interested. Just PM me.Click to expand...I"d be very interested in an operators manuel if you have one....my father in law just purchased a 1992 Hitachi EX120-2....he's been doing dirt work for 30 years, but all with a backhoe and dozer...the excavator is new to him, and all the instructions in the cab are in Japanese...[email protected]ANY information you can send on the EX120 would be greatly appreciated

I have been helping the father-in-law with his EX120-2 (serial 12N-35444)as we have some real issues with. the machine would run untill it was hot and then any work on the hydraulics would be like this one in this tread, lots of black smoke with the hydraulics loading it up something shocking. We have had issues with the Hydraulic computer dying as well as the odd fuse blowing. To cut the story short, the computer had a resistor burned out (R1, 10 ohm 4W) This was replaced and all the push button modes came back to life and I think we had to replace Fuse 6, Sw.Box. All seemed ok, but when we had a big job and the maching had to work hard for 30-45 minutes, then the fault returned.I had monitored the heat on the resistor when we started and it was ok, but it had failed again. We have since put another resistor in and I cant seem to find anything else faulty on the computer (I am an electronic tech by trade) and done a search of the whole machine for wire shorts etc and did finally find one on the wires to the quick hitch solenoid, the insulation had rubbed through and may have been randomly shorting the 24V outs. That may explain the fuse failures. We then (after reading the posts here) measured all the coil (solenoids) resistances, all (SA, SB etc)were around 23 ohms on the digital meter, however SI measured 60 ohms, (I dont have the manual to show what each one controls, but the wiring loom was labeled) but this is a slightly different device in appearence, is this normal? It seemed stable, so I concluded that it may be ok and felt that since the computer pulled to ground to turn it on, it would be unlikely to cook the resistor in the computer which is on the 24V rail.... Again to cut the story short, we restarted digging and were working it hard for some time, a trench in mud rock 8' deep 40' long 4' wide before the hydraulics stopped again, with the computer down with R1 overheated....Without a detailed circuit diagram, I'm a little lost for ideas now....Has anyone had issues with the computer blowing after working the machine to it gets hot? We were quoted around $3K for another computer, so it isnt a easy thing to replace when it's likely to blow from something external to it.Suggestions anyone? Are circuits available anywhere?

:canada Send me a PM with your email address and I will send you the schematics.

-3Doc said::canada Send me a PM with your email address and I will send you the schematics.Click to expand...Hi 3Doc, thanks for the kind offer, I am a newbie here, so dont seem to have permissions to email you.... or I just cant seem to find you info without getting a permission problem. However, my email is[email protected]I hope that doesnt violate the rules here....

Hi 3Doc, I'm looking for the manual for an EX120-2 also. If you could PM the manual, I'd be very greatful. Thanks.

me too plz

I can't start my on thread yet, so I'll ask here.....paw-in-law says the swing manifold has a small leak....it that just an O-ring?

490eWe have replaced the pump drive in a 490E and are now having trouble with the up boom function. No solenoids or sensors were removed from pump and all wires were carefully marked and replaced. All other functions work correctly. At idle it lifts fine but as soon as engine revs boom slows. It also suddenly worked great for about an hour then started messing up again. Boom down works great only booming up is giving problems. Any ideas?

Just a thought, I have had a few hitachi /3 and /5's and some have a banjo fuel filter in the fuel line as it enters the pump. (A bitch to get at!) Maybe something of use on another day.

Oh, and I've got Hitachi manuels for EX120 /3 and/5 excavators if anyone needs page.

duck_nutt said:I can't start my on thread yet, so I'll ask here.....paw-in-law says the swing manifold has a small leak....it that just an O-ring?Click to expand...If the manifold is leaking out the top then it is time for a reseal. The manifold must be removed and pushed apart and all seals and orings replaced. Not a huge job but you must use a press to push it back together.:canada

Thanks for the fuel line info. I will remember this.

Deere / Hitachi Pump controlerDoes anyone know the specs on the diode in the pump controler on the power inlet pin number 37 on the connector ?

thanks -3Doc....i'm an air traffic controller, but the longer I stay around my father in law, I'm turning into a mechanic....helped him put on new seals on the 2 boom cylinders and the 1 arm cylinder....those things are kinda heavy!

Help on EX120-2 PVC computer1st AD said:Does anyone know the specs on the diode in the pump controler on the power inlet pin number 37 on the connector ?Click to expand...If you are talking about the PVC computer for the Hitachi EX120-2, I have one on my desk right now I'm trying to fix.... The diode, labeled D1 is in series with a 4W 10 ohm resistor, on the Father-in-laws machine, which I have to fix the resistor was blown open and the diode went short circuit, so I have had a massive overload there to do that. The diode has no markings, but if you consider the power rating of the resistor, then the max current would only be around 0.6A( for max power rating on the resistor), but it seems to pull only 0.15 to 0.22 A on normal operation, so just about any generic diode probably would work. I used another glass passivated diode rated at about 1.5A that is just a fraction larger than the original, but any 1A diode should work. If you have a simular issue to me, then I'd be interested in what else you find. My email is a few posts back. I replaced the resistor then it all worked fine in the machine for over half an hour of hard work, then suddenly blew again. I'm an electronic tech but I cant reproduce the fault. However, the computer is still faulty. (tried in another machine)Does anyone have the schematics for these computers? Or a cheap second hand computer!

I have the exact same issues with my EX100, I dont know wich generation it is but i think its a gen 2. I can tell its a 1994 and it has the round corner cab and a 4cyl non-turbo with a mechanical fuel injection pump control over cables to electric motor. fuel filter is new and blown all the lines to make sure they are clean and its still bugging/stalling when any hydrolics fuction are activated. it does it from dead cold to hot. It might be selenoids or sensor on the pump.3-Doc do you have the repair manual for the EX100-2

Have you guys looked at the air inlet hose that goes from the air filter housing to the turbo,they get soft and will collapse when there warm and under load. Causing black smoke and stalling , this is a common problem on older Hitachi and John Deere machines, just have some one stand up top while unit is under load to see if it collapses.Hope this helps

EX 120-2 ManualsHi -3DOC,New member here, was browsing through this forum as i too had the same problem with my EX120-2 going back some weeks ago and after alot of trouble shooting i found that one of the pump solenoid valves was defect and since i changed it my machine is working perfect, Basically i was wondering if you tell me where i can get my hands on Tech manuals, wiring diagrams and illistrated parts catalog for this machine as it never came with any. I have searched through the internet a few times and still can't come up with anything. I would be most gratefull if you could help me out on this, thanks

I went working on our EX100 and starting with the fuel system changed the filter and verified for the banjo fitting and the mesh was missing. it had a 15amp fuse blow, I beleive it was the 3rd one in the second row of fuse the fuse door is missing so i dont know whats it was use for. I tried to swap the connection on the selenoid and didn't do anything different. I recalibrated the angle sensor to 4.40V on the dot after running the engine idle for 4 min with selenoid unplug. It improuved a little after but its not working perfectly.What is the normal resistance in the selenoid valve. The engine sounds like its under constant load.

TraxterMaster said:I went working on our EX100 and starting with the fuel system changed the filter and verified for the banjo fitting and the mesh was missing. it had a 15amp fuse blow, I beleive it was the 3rd one in the second row of fuse the fuse door is missing so i dont know whats it was use for. I tried to swap the connection on the selenoid and didn't do anything different. I recalibrated the angle sensor to 4.40V on the dot after running the engine idle for 4 min with selenoid unplug. It improuved a little after but its not working perfectly.What is the normal resistance in the selenoid valve. The engine sounds like its under constant load.Click to expand...Is the engine under load as soon as you start it or only after you put the safety lever down?:canada

Well it resonates in the cab at idle more then it use to. the lever up or down doesn't change the sound of the engine. also forgot to mention the connection at the RPM sensor on the pump was broke, I replaced the connection still does not work properly. If crawl slowly but steady on flat ground you can hear the engine trying to keep up but still bugs down to a stall if i push too much. I was barly able to put it back on the trailer to bring it home yesterday. The engne load is pretty high because you could see the heat mirrage over the engine cover after I stoped it. Theres alot of wires in this machine that need to be looked at but a wiring diagram could be useful. my temp gauge doesn't work and alternater light is on but it charges. :canada me too

timmydid you get the schematics as i need it toigor said:If you are talking about the PVC computer for the Hitachi EX120-2, I have one on my desk right now I'm trying to fix.... The diode, labeled D1 is in series with a 4W 10 ohm resistor, on the Father-in-laws machine, which I have to fix the resistor was blown open and the diode went short circuit, so I have had a massive overload there to do that. The diode has no markings, but if you consider the power rating of the resistor, then the max current would only be around 0.6A( for max power rating on the resistor), but it seems to pull only 0.15 to 0.22 A on normal operation, so just about any generic diode probably would work. I used another glass passivated diode rated at about 1.5A that is just a fraction larger than the original, but any 1A diode should work. If you have a simular issue to me, then I'd be interested in what else you find. My email is a few posts back. I replaced the resistor then it all worked fine in the machine for over half an hour of hard work, then suddenly blew again. I'm an electronic tech but I cant reproduce the fault. However, the computer is still faulty. (tried in another machine)Does anyone have the schematics for these computers? Or a cheap second hand computer!Click to expand...

timmyyou can go to the john deer bookstorewww.johndeeretechinfo.comlook up 490e it is the same hitachi make john deernewbe said:Hi -3DOC,New member here, was browsing through this forum as i too had the same problem with my EX120-2 going back some weeks ago and after alot of trouble shooting i found that one of the pump solenoid valves was defect and since i changed it my machine is working perfect, Basically i was wondering if you tell me where i can get my hands on Tech manuals, wiring diagrams and illistrated parts catalog for this machine as it never came with any. I have searched through the internet a few times and still can't come up with anything. I would be most gratefull if you could help me out on this, thanksClick to expand...

with john deeres or hitachi there are two sensors - pressure differential sensors located on the main hyd c/v.if the hyd sensors malfunction then the hyd pump control will not work right.this could be your problem.i would suggest you do cycle times on each track.lift track in the air and mark one shoe with paint.line up paint markrun track and time total of 3 revolutions.do the same for the oposite track.you may see a diff between each pump.swap sensors on main c/v and retake cycle times see if they swap as well.does the machine track straight?also what hyd pump do you have?kawasaki mfg# ?normally many hyd pump repair shops are not setup to rebuild/reseal hyd pump regulators for they do not have a test bench that can verify calibration of the pump.flows/pressures.likely the regulators were not touched.

Hitachi 120-3I have a machine that has low power to the tracks, and low power on the swing. There is a bank of solenoids that are unplugged, but if they get plugged in the tracks and swing stop completely. Is the computer in limp mode? I ohm tested the solenoids(7 total), all but one were @ 24.Ohms, the one for the right track motor was 68 Ohms. not sure what the spec is on them. Center joint seals are all new, I tried swapping the solinoids on top of the main pump, but no change. They both tested the same for ohms. ??-3DOCcan you help with how to check the voltage of the angle sensor, and what it should be? Any help would be appriciated.

Bula guys, new kid, been following this thread with interest. Original problem was with engine loading. a "repairman" had a look and said the problem was in the control unit.got that serviced but not only original problem but now the left joystick controls the left track. oh boy!!He got the piping wrong. ex100-3. help!!!

fijijoe said:Bula guys, new kid, been following this thread with interest. Original problem was with engine loading. a "repairman" had a look and said the problem was in the control unit.got that serviced but not only original problem but now the left joystick controls the left track. oh boy!!He got the piping wrong. ex100-3. help!!!Click to expand...Welcome to the forum fijijoe. :usaI think the best thing you could do is get the repaiman back out there and have him get the piping sorted out.

fijijoe said:Bula guys, new kid, been following this thread with interest. Original problem was with engine loading. a "repairman" had a look and said the problem was in the control unit.got that serviced but not only original problem but now the left joystick controls the left track. oh boy!!He got the piping wrong. ex100-3. help!!!Click to expand...I have a few questions that need to be answered before I can help you.1. What do you exactly mean by "engine loading"?2. By control unit, do you mean the computer or the valve block?3. Does the left track pedal now control the stick?He probably switched around a few pilot lines.

Bula Sultan,to answer your questions1.the engine stalls if any lever is activated,i.e tracks or swing/stick. if it is nursed slowly, it picks up, but if it is used normally the engine labors or stalls.2.valve block3. yes, the bucket cylinderi am sure that he switched the pilot lines. i got this machine 2nd hand w/out any manuals, am not familiar with piping yet.

Thanks ATCOEQUIP,i've been trying to get him back for over a month to sort out the pilot lines. no such luck yet.

I also have an ex 120-2 I have a melted Yellow wire with red tracer. It goes to the top front Solenoid valve on the left side of the valve bank, From the fuse panel. I ran a new wire and when I plug it back in to the solenoid it blows the # 9 Fuse (solenoid fuse) How do I check to see if the Solenoid is bad or if it is the angle sensor ? Thanks

By the way my machine is doing the same thing , At the end of the stroke motor tries to die also on the swing it tries to die and machine chatters . You can tell that the pump is loading up Thanlks again

Hi all, new to this forum. instresting !!

Could i get one too -3doc ?

Are these turboed engines?

yes

I hate to sound like captain obvious but has anyone checked to make sure the turbos havent went down on them?? if the air filter is clean, and the air inlet screen is clean and thier still overheating and blowing black smoke. sounds like my old hitachi 200 when the turbo crapped out.

hi -3Doc,i also have this same problem on my ex 120-2, i was able to remove the pvc unit on my other and it works for 5 days and then there is new problem.now its the stick problem. when you give little movement on the stick it loads the engine. when you give extreme on stick its also to fast.it seems he can only sense extreme signal.what is this problem?? help please also if you can send me electrical schematics or service manual is very helpful. thank youmy email is[email protected]

rgl726 said:hi -3Doc,i also have this same problem on my ex 120-2, i was able to remove the pvc unit on my other and it works for 5 days and then there is new problem.now its the stick problem. when you give little movement on the stick it loads the engine. when you give extreme on stick its also to fast.it seems he can only sense extreme signal.what is this problem?? help please also if you can send me electrical schematics or service manual is very helpful. thank youmy email is[email protected]Click to expand...This seems to be a problem for a lot of people out there!! I am a little overwhelmed by all the questions about pump controls.I will try to explain how the system works and the most common problems that can cause the -2 blues as I call them!There are 4 sensors that monitor the system and tell the computer what is happening so it can control the pumps.#! N sensor, this is the small sensor on the top of the hyd pump that monitors the RPM of the engine.#2 P sensor , is the sensor on the outlet port of the pump that monitors the pressure that the pumps put out.#3 A sensor, the small can shaped sensor on the side of the hyd pump, this monitors the angle of the swash plate inside the hyd pump to tell the computer how much oil the pump is tying to put out.#4 DP sensor , is the can shaped sensor on the top and in the middle of the control valve. This tells the computer the difference in pressure between what the pump is putting out and what the valve bank is using.If the wiring to any of these sensors is bad or the sensors are bad or the fuses are bad all of your pump control is lost and many of the above problems can occur.Shall I continue with diagnosing where to start!!!?

I have found that most hyd. problems on these machines are electrical problems! If the computer can not see what the pump is doing it will basically shut down and the pumps will slowly go to full swash and put out way too much oil and everything will speed up and loose power and the engine will be overwhelmed and smoke black smoke and stall.The biggest problem is crispy wiring in the pump aria that has broken or shorted out, this is the best place to start looking. also check the fuses and make sure they are all good and also the right ones in the right places. this is very important so you don't fry your computer!!

hi guys, anyone got any schematics for pilot piping to control valve block for a hitachi ex100-3. would be obliged for any help.

Thanks 3doc,i trace all the wiring linking the all the pump solenoid and sensors and all has a continuity inside the cab with no ground.How will i test this sensors if they are good or bad?Angle sensorpressure sensorrpm sensorand the sensor in the control valve

rgl726 said:Thanks 3doc,i trace all the wiring linking the all the pump solenoid and sensors and all has a continuity inside the cab with no ground.How will i test this sensors if they are good or bad?Angle sensorpressure sensorrpm sensorand the sensor in the control valveClick to expand...Send me a PM and I will get the info to you.Thanks.

hi -3doc,i would like to ask where is the homerun of the swing dampener sensor?i was able to trace one wire to the pvc but i cant find the other one in the pvc or ecu?i was able to trace it only up to the smj connector but from smj to the pvc or ecu i cant find it?is the other wire going somewhere else rather than the pvc or ecu?

rgl726 said:hi -3doc,i would like to ask where is the homerun of the swing dampener sensor?i was able to trace one wire to the pvc but i cant find the other one in the pvc or ecu?i was able to trace it only up to the smj connector but from smj to the pvc or ecu i cant find it?is the other wire going somewhere else rather than the pvc or ecu?Click to expand...Here is wiring schematic.

Dose any one know what Code 22 is on a EX120-2 and how to fix it Thanks

Hi guys,Had a similar problem which i have posted in another thread, but if its any help we had a problem on a 97 Hitachi EX200-3. The machine was overheating after about 20mins of working. Both engine and hydraulic oild were getting very hot and the machine would stall.So one of the local techies swapped a DP sensor and everything was sorted!Hope this info helps

Hi -3 Doc,New here but having same problems as everyone else. Cylinders on 120-2 max out and machine dies. I've traced entire wiring harness. Repaired wiring harness to solenoid valves but still doing the same thing. Are there any codes that the computer can give as to the problem? How do I get the computer to give me the codes?Please help.

I failed to mention that there is 25 volts going to both solenoid valves on the yellow wires but I'm not reading any voltage on the engine speed sensor that's next to the angle sensor.

code 22 is problem with the angle sensor, high speed solenoid and, PVC.

Clay35441 said:Hi -3 Doc,New here but having same problems as everyone else. Cylinders on 120-2 max out and machine dies. I've traced entire wiring harness. Repaired wiring harness to solenoid valves but still doing the same thing. Are there any codes that the computer can give as to the problem? How do I get the computer to give me the codes?Please help.Click to expand...Clay send me a PM and I will help you with some printed procedures.

-3Doc said:Clay send me a PM and I will help you with some printed procedures.Click to expand...Not sure how to send a pm. Here's my email address[email protected]

Not sure how to send a pm

ex120-2 throttle motor will not respond, have repalced motor, sensor, and rebuilt circut board. throttle motor only humes for a few seconds and then stops, will not move. I was also told if you unplug the motor and turn the key on this will cause the circut board to burn up. Is the true?? need help

-3docThanks to your help I've found that my problem is the Q5 resistor inside my pvc. Where can I buy replacement resistors?

hi can somebody help me??? i need a ex120-2 repair manual, schematics, the hydraulics system is very slow, the hydraulics is like on the limp mode...

auy_tong2 said:hi can somebody help me??? i need a ex120-2 repair manual, schematics, the hydraulics system is very slow, the hydraulics is like on the limp mode...Click to expand...maka ayo ta ana sir.

im looking for a manual sir

up up

Send me a PM and I can help you with manuals.

Can anyone tell me what the ohm and voltage ratings are on the Q5 transistor are inside the pvc. I'm having trouble finding the transistor because there aren't any markings on it. EX 120-2

the problem in the pvc is not only on the transistors.there are other ic needs to be replaced.

Hi guys,Has anyone here managed to get hold of the shop manual for the EX120-3? I am badly in need of one as the engine on our EX120-3 stalls as soon as the hydrualics get any load. The engine just wont rev up when the hydraulics are loaded (either boom nor travel motors). Much appeciated if anyone can send me a shop manual for this machine to help me troubleshoot the problem.Cheers

Sripola said:Hi guys,Has anyone here managed to get hold of the shop manual for the EX120-3? I am badly in need of one as the engine on our EX120-3 stalls as soon as the hydrualics get any load. The engine just wont rev up when the hydraulics are loaded (either boom nor travel motors). Much appeciated if anyone can send me a shop manual for this machine to help me troubleshoot the problem.CheersClick to expand...Could be a fuel delivery problem, (thats what I had)Check your fuel filters, or just replace, check the banjo filter in the fuel line, and check the line coming from the gas tank, its tends to get clogged. Thats the 1st easiest things to check off.

Hey Wardiker,We changed all the filters and checked the banjo and gave it a good clean up. Still no luck.We've got a Hitachi "specialist" coming in and said something about converting the machine to run by bypassing the sensors. See how that goes cuz the sensors on these machines I know have caused lots of people a problem

Sripola said:Hey Wardiker,We changed all the filters and checked the banjo and gave it a good clean up. Still no luck.We've got a Hitachi "specialist" coming in and said something about converting the machine to run by bypassing the sensors. See how that goes cuz the sensors on these machines I know have caused lots of people a problemClick to expand...Thanks for the heads up, mine was that someone had joined a foot of new line just from the tank to the old, when they heated it up to connect it melted and had a pin hole size to let let the fuel in, we laughed, counted our blessings and she runs great, make sure you post your solution.

Hi Wardiker,I just noticed on our machine that the machine spews out a puff of black smoke just before the engine dies. Also i noticed that the hydraulic oil tank was getting very hot. I mean i couldnt keep the back of my hand on the side of the tank for more than a couple of seconds it was that hot after just travelling back and forth for about 20min.But we sold a EX200-3 some months ago and it had a somewhat simmilar issue. The engine was overheating after working for about 20min and just die. Tried everything like you suggested like the filters etc and it turned out it was a bad DP sensor. Got a spare part for about $400 and plugged in in and straight away the machine was working just fine. So its the same fella coming around to repair this one and hopefully can work his magic again!ANd i will def post the solution if we get it fixed.Cheers,imran

Well guys, I'm back. I finally found someone that could fix the pvc on my ex120. It's still stalling the engine and controls are fast. I went back and read all the posts. I'm going to test the angle sensor and dp sensor this weekend. My pvc is showing a code 22 and 31. Does anyone know what this means? I've also got one other problem, when you mash the (P) or Power button the engine revs up and dies. This has been going on since I've owned it, even before the hydraulic problem. Does anyone know what would cause this, maybe the ec motor.

Clay35441 said:Well guys, I'm back. I finally found someone that could fix the pvc on my ex120. It's still stalling the engine and controls are fast. I went back and read all the posts. I'm going to test the angle sensor and dp sensor this weekend. My pvc is showing a code 22 and 31. Does anyone know what this means? I've also got one other problem, when you mash the (P) or Power button the engine revs up and dies. This has been going on since I've owned it, even before the hydraulic problem. Does anyone know what would cause this, maybe the ec motor.Click to expand...Id start a new thread stating your model, Im sure someone could help, might get burried in this thread though.

Clay35441 said:Well guys, I'm back. I finally found someone that could fix the pvc on my ex120. It's still stalling the engine and controls are fast. I went back and read all the posts. I'm going to test the angle sensor and dp sensor this weekend. My pvc is showing a code 22 and 31. Does anyone know what this means? I've also got one other problem, when you mash the (P) or Power button the engine revs up and dies. This has been going on since I've owned it, even before the hydraulic problem. Does anyone know what would cause this, maybe the ec motor.Click to expand...code 22 is abnormal pump controlyou should look at the following component:angle sensorhigh speed solenoidPVCcode 31 is disconnected hyd oil temp sensor or short circuit of the sensor harness

Hi Wardiker,Happy New Year!Well we found the problem and also a theory on how it happened.Well basically the PVC is fried. Overvoltage had blown a whole bank of transistors and a couple of resistors. Also noticed that someone had messed aorund with the angle sensor. So our techie adjusted it "manually" by setting it so that the pump doesnt overheat (i couldnt find the correct calibration instructions for it so had to go with our guy's logic).The guys took the PVC and repaired it (cost about $200), and we tried a donor PVC and found machine worked perfectly. But put the repaired PVC and machine was ok apart from auto throttle not reponding. So the guy's gonna take a second shot at it and hopefully fixes it this time!So the theory on how this all happened. We found a pressure sensor for the machine travel was inop. So it looks like someone had tried to adjust the angle sensor to fix this (cuz they didnt know the presssure sensor was inop), and made the prob worse. The next dumb move by this mystery mechanic was prob to have put a voltage through to pin out the harness and thus blowing the PVC. Because when we got to it we could see signs that someone had already been there messing around.SO hope this info helps. But basically, adjusted the angle sensor, fix/new PVC and a pressure sensor and the machine's a good un!Also our techie told us that there is a bit of kit to bypass all the sensor and make the machine a "manual" although this makes the machine run slower and not very efficient as you can imagine, so if anyone has info on this procedure i am more than interested as i have heard this procedure from quiet a few guys but its almots an urban legend as no one can give me any technical info on this.

490E excavator-3Doc said:With the key on and engine not running you should have 24volts to one wire on each of the displacement solenoids, (the ground is controled by the computer and you can not check this easily.) If you don't have 24 volts to each solenoid then you can check the fuses first there is a one amp fuse for each in the fuse box. Make sure they are good then go from there and check the wiring from the fuse box back to the solenoids. Hope this helps.:canadaClick to expand...Hey 3Doc, I have been tryin to log into this forum for very long time now, my password wont reset must be some admin issues, so i created a new account. My previous username was andre01.Thanks for the suggestions, I got 21.7 volts across each solenoid, i guess thats bcaz the battery was low, with the engine running i get 26volts.Since my last post i did a lot of things.1- I replaced the displacement solenoids with new ones.2- Resealed the swing motor3- replaced two solenoids on the pilot solenoid valve ( boom and swing function)4- replaced the DP sensor on the control valve5- Replaced the PVCSo here is where I am after that. The machine was overheating , was super fast, would easily stall at full extension of any cylinder or under load, and the hammer would stop firing if i move any other function while hammering b4 i replaced the DP sensor,Now it is not overheating , functions can be operated simultaneously therefore no problem when hammering and will not stall provided that I select tortoise mode and a power greater than Idle.If I am not wrong, of the two solenoids on the pump, one is for increasing flow and the other for decreasing. I have noticed however that the machine will not overheat and such if the wires are switched around.When i connect the wires as they should It overheats, but the machine is very strong and as fast as it should be and will not stall provided i select tortoise mode and a power mode greater than idle (eg. L).Mayb i am wrong plz inform me of which wire ( color code) goes to the solenoid nearest to the door/ front.My next big prob is that the swing is very weak, all other function are strong except swing, The machine fails trying to sweep an object to the side. Also when on a hill I hav noticed that when swinging the machine it will not come to rest quickly when the lever are in neutral, it swings a good bit b4 comin to a stop.Angle senor voltage is 4.4volts, i blew air through fuel line back to tank and drain tank which gave improvements in speed. what range voltage should i get on the rpm senosr?My temp gauge doesnt work.Any Ideas? Thanks.

Andre-1 said:Hey 3Doc, I have been tryin to log into this forum for very long time now, my password wont reset must be some admin issues, so i created a new account. My previous username was andre01.Thanks for the suggestions, I got 21.7 volts across each solenoid, i guess thats bcaz the battery was low, with the engine running i get 26volts.Since my last post i did a lot of things.1- I replaced the displacement solenoids with new ones.2- Resealed the swing motor3- replaced two solenoids on the pilot solenoid valve ( boom and swing function)4- replaced the DP sensor on the control valve5- Replaced the PVCSo here is where I am after that. The machine was overheating , was super fast, would easily stall at full extension of any cylinder or under load, and the hammer would stop firing if i move any other function while hammering b4 i replaced the DP sensor,Now it is not overheating , functions can be operated simultaneously therefore no problem when hammering and will not stall provided that I select tortoise mode and a power greater than Idle.If I am not wrong, of the two solenoids on the pump, one is for increasing flow and the other for decreasing. I have noticed however that the machine will not overheat and such if the wires are switched around.When i connect the wires as they should It overheats, but the machine is very strong and as fast as it should be and will not stall provided i select tortoise mode and a power mode greater than idle (eg. L).Mayb i am wrong plz inform me of which wire ( color code) goes to the solenoid nearest to the door/ front.My next big prob is that the swing is very weak, all other function are strong except swing, The machine fails trying to sweep an object to the side. Also when on a hill I hav noticed that when swinging the machine it will not come to rest quickly when the lever are in neutral, it swings a good bit b4 comin to a stop.Angle senor voltage is 4.4volts, i blew air through fuel line back to tank and drain tank which gave improvements in speed. what range voltage should i get on the rpm senosr?My temp gauge doesnt work.Any Ideas? Thanks.Click to expand...here is the first thing to do with the ovrheating problem.remove the engine thermostat and observe the machine.this is located on the engine water return line to the radiator.pdsv 1 is one near the door. pdsv 2 is near the engine.

rgl726 said:here is the first thing to do with the ovrheating problem.remove the engine thermostat and observe the machine.this is located on the engine water return line to the radiator.pdsv 1 is one near the door. pdsv 2 is near the engine.Click to expand...It is the hydraulic oil that gets hot, I measured with a heat gun and it showed 180 degrees fahrenheit at the pump, and drops to 120 after the oil cooler. So i suspect this hot pump results in a hot engine since they r connected.when i reverse the wires connected to the displacement solenoids the machine does not overheat and the oil temp is like 120 fahrenheit and colder after the cooler.I would like to know which colour wire is supppose to connect to which solenoid in order to ensure that it is connected correclty.however when connected as i think it shud it is very strong, stronger than b4 and fast, but it overheats. so I suspect the computer ground to one of the solenoid has lost connectivity.I would like to know how to test the pressure sensor, speed sensor and to test the computer ground to the solenoids.

you need to test is with a 24v L.E.D light. remove the connectors of the pump solenoid and connect the 24v L.E.D light.do not use any light bulb other than L.E.D. i recommend L.E.D due to lower wattage rating. thats the reason why i specify L.E.D.move the boom stick up and down. observe the L.E.D if it will light up.test them one at a time.

test

Hi all,Do you know if its a big job to change the ring rear (the wheel that the starter connects too) on a EX120-2 ?Thanks,John

No Not to big of a job John, you maybe able to leave the pump in place, just drop it back a bit to get at the fly wheel!Also you might what to replace the rear crankshaft seal when your in there!Aiden

-3Doc said:I have sent you an email with the page from the manual to set the voltage. Let me know how it works.Click to expand...if you have ex200 lc manual pl send ([email protected])i have same problem spunkeymonkey machine havemy machine have wire huness shortPVC control card resistant damage

what is resistant oms and voltage nears diode numberwhat is the day you send email to methis 3 part are damage

Thanks Aiden,Did you ever get your shop set up ?

Hi 3Doc,We have a Hitachi EX200-3 machine that is having the same hydraulic problem as everyone has been experiencing on these threads... The PVC computer has been disconnected as well as all the sensors and our mechanic cant put these back together so I think that would explain the hydraulic problems etc. According to him they have operated this machine for months and was working fine with the computers disconnected and the sensors disconnected as well. Is this possible?I have suggested that the PVC computer and sensors be connected back but we are in need of a manual for the wiring diagram and probably the hydraulic diagram as well as they have dismantled everything now. Thanks to my very brilliant mechanics!

Sorry I cant PM you as I am a probationary member only. My email address is[email protected]

-3Doc said:I can supply you with one if you are interested. Just PM me.Click to expand...Hello, I am new to this forum. Never had a real reason to join until a few days ago when I pulled the trigger on a new to me Hitachi EX120-2. I am sure I will be back on this or other threads. If this offer is good to others I would love a copy of the full service manual. If not, can you tell me what the differences are between the EX120-3 and the -2?Thanks in advance. I woul PM you but do not have those privliages yet. my email: tom(at)troutcreektreefarm(dot)comTom

Sripola said:Hi Wardiker,Happy New Year!Well we found the problem and also a theory on how it happened.Well basically the PVC is fried. Overvoltage had blown a whole bank of transistors and a couple of resistors. Also noticed that someone had messed aorund with the angle sensor. So our techie adjusted it "manually" by setting it so that the pump doesnt overheat (i couldnt find the correct calibration instructions for it so had to go with our guy's logic).The guys took the PVC and repaired it (cost about $200), and we tried a donor PVC and found machine worked perfectly. But put the repaired PVC and machine was ok apart from auto throttle not reponding. So the guy's gonna take a second shot at it and hopefully fixes it this time!So the theory on how this all happened. We found a pressure sensor for the machine travel was inop. So it looks like someone had tried to adjust the angle sensor to fix this (cuz they didnt know the presssure sensor was inop), and made the prob worse. The next dumb move by this mystery mechanic was prob to have put a voltage through to pin out the harness and thus blowing the PVC. Because when we got to it we could see signs that someone had already been there messing around.SO hope this info helps. But basically, adjusted the angle sensor, fix/new PVC and a pressure sensor and the machine's a good un!Also our techie told us that there is a bit of kit to bypass all the sensor and make the machine a "manual" although this makes the machine run slower and not very efficient as you can imagine, so if anyone has info on this procedure i am more than interested as i have heard this procedure from quiet a few guys but its almots an urban legend as no one can give me any technical info on this.Click to expand...Hi guys,So much for the early celebrations! Our Hitachi EX120-3 has developed the same problem again! We got the electronics "expert" to fix teh PVC and it worked for about 6 hrs before blowing it again.Not sure what to do now as a few ppl have messed around and teh waters a bit muddied. Any suggestions guys as to what could be causing it? Bad DP sensor? The machine tracks very slowly as well no matter what you do. And after working for a few minutes or any load on the hydraulics it just stalls.Might replace the PVC and see what happends but the risk is another blown computer and no root cause.ANy help is appreciated and if someone has the service manual etc that would be great.Cheers

Just throwing it out there but my Hitachi ex300lc-3 did the same thing I placed the prussure release valve on the hydraulics and bam back to work I went best of luck with yours and mine also had a problem sometimes when I turned my machine on it wouldn't rez up at all but had to replace the stupid motor that controls the throttle postion.

Sripola said:Hi guys,So much for the early celebrations! Our Hitachi EX120-3 has developed the same problem again! We got the electronics "expert" to fix teh PVC and it worked for about 6 hrs before blowing it again.Not sure what to do now as a few ppl have messed around and teh waters a bit muddied. Any suggestions guys as to what could be causing it? Bad DP sensor? The machine tracks very slowly as well no matter what you do. And after working for a few minutes or any load on the hydraulics it just stalls.Might replace the PVC and see what happends but the risk is another blown computer and no root cause.ANy help is appreciated and if someone has the service manual etc that would be great.CheersClick to expand...first thing to do is replace and adjust the angle sensor before you go to the PVC.

Finally fixed the bloddy thing!Frayed harnesss!!!!! cant believe it was so simple! I dont know exactly where it was shorting because our mechanic didnt really note it, but it was underneath the cab so i think it was one of the in/outs from either PVC or EPC.Thanks for all the suggestions guys, once i have more details will post it here as i am sure it will help someone!

Having wiring problem in the pump area, and if you could send me a wiring diagram of pump selnoids, all the wires have been tore out and I have replaced them the best I could, but to have a wiring diagram would be greatly appreciate. I know this is old post, but haven't seen anyother close to what I need.My email address is[email protected]. Thanks, Mike Bentley

Is it 24Volts that must be sent to the solenoids on the pump of a 490e Excavator? or does it vary . I tested using a multimeter while the machine was running and got variations; 6volt, 8 volts, 13 volts (was the highest) . I know the ground is controlled by the computer (PVC) but when it grounds must the voltage be 24v or does it vary based on the load.I ohm tested my rpm sensor and got 862 ohms. This machine has blown a pvc before so i suspect a bad harness. Before, it stalled when under load or if any cylinder was fully extended. I changed the DP sensor and adjusted the angle sensor. got better results when i changed the dp sensor,now it wont stall in any mode higher than (I). If i switch the wiring for the solenoids it overheats. While testing it today I noticed the voltage on one was always higher than the other. one shows like 6v,7v, 8v while the other shows 6, 8, 13v . the state it is in now is that it will come to a stop while working and will only move after the levers are released and the moved again, seems like low oil flow. I ran a self diagnosis and it gave code 28 ( pump dischagre pressure sensor) so i purchased it and it will take a while to get here. Any suggestions?

storm1nHere are the workshop and tech manuals for dash 5 .maybe they will help.I do not have them for the 200lc-3 but have the for the dash 5 machines here are the links for the manual download these hopefully they will help.These are the tech manuals .http://www.4shared.com/document/Btmp...ONTENTS_1.htmlhttp://www.4shared.com/document/WWhl...ENTS_157T.htmlhttp://www.4shared.com/document/m2nd...157T-2-1_.htmlhttp://www.4shared.com/document/sy8j...TS_157T-5.htmlhttp://www.4shared.com/document/W1A0...ERAL_INFO.htmlTheses are the work shop manualshttp://www.4shared.com/document/jk11..._157W-1-1.htmlhttp://www.4shared.com/document/aBu8...S_157W-2-.htmlhttp://www.4shared.com/document/VJ1m...ssorieW05.htmlhttp://www.4shared.com/document/0l-m...orieW05_2.htmlhttp://www.4shared.com/document/Kmyk...S_157W-3-.htmlhttp://www.4shared.com/document/ZkAP...ENTS_157W.htmlhttp://www.4shared.com/document/EJG4...157W-4-1_.htmlHere is the parts manual for the machinehttp://www.4shared.com/document/b1Ls...PARTS_CAT.htmlhttp://www.4shared.com/document/Vr8O..._H_PARTS_.htmlIf is the Japanense version let me know because the manuals are a little differen for both workshop and tech.Hopefully these will get the answer you need.Do you have access to the Dr.Ex scan tool or the Hitachi Win Dr. for laptop ? Hop this might help with this .

tool king those links dont work, it says link not valid

tool_king said:storm1nHere are the workshop and tech manuals for dash 5 .maybe they will help.I do not have them for the 200lc-3 but have the for the dash 5 machines here are the links for the manual download these hopefully they will help.These are the tech manuals .http://www.4shared.com/document/Btmp...ONTENTS_1.htmlhttp://www.4shared.com/document/WWhl...ENTS_157T.htmlhttp://www.4shared.com/document/m2nd...157T-2-1_.htmlhttp://www.4shared.com/document/sy8j...TS_157T-5.htmlhttp://www.4shared.com/document/W1A0...ERAL_INFO.htmlTheses are the work shop manualshttp://www.4shared.com/document/jk11..._157W-1-1.htmlhttp://www.4shared.com/document/aBu8...S_157W-2-.htmlhttp://www.4shared.com/document/VJ1m...ssorieW05.htmlhttp://www.4shared.com/document/0l-m...orieW05_2.htmlhttp://www.4shared.com/document/Kmyk...S_157W-3-.htmlhttp://www.4shared.com/document/ZkAP...ENTS_157W.htmlhttp://www.4shared.com/document/EJG4...157W-4-1_.htmlHere is the parts manual for the machinehttp://www.4shared.com/document/b1Ls...PARTS_CAT.htmlhttp://www.4shared.com/document/Vr8O..._H_PARTS_.htmlIf is the Japanense version let me know because the manuals are a little differen for both workshop and tech.Hopefully these will get the answer you need.Do you have access to the Dr.Ex scan tool or the Hitachi Win Dr. for laptop ? Hop this might help with this .Click to expand...It's a john deere 490e but most of its components are hitachi made such as the control valve and other things. I dont have Win Dr or Dr. EX scan tool. Please repost the links, those dont work. Thanks

Please disreguard last my post #130 links were messed up not working .Something must have not been right with last links. Here are the new links.Tech manualshttp://www.4shared.com/document/BtmppIqz/COMPONENT_OPERATION_CONTENTS_1.htmlhttp://www.4shared.com/document/WWhlVJFX/PROFORMANCE_TEST_CONTENTS_157T.htmlhttp://www.4shared.com/document/m2nd3EDJ/SYSTEM_CONTENTS_157T-2-1_.htmlhttp://www.4shared.com/document/sy8j_mEf/TROBLESHOOTING_CONTENTS_157T-5.htmlhttp://www.4shared.com/document/W1A0H049/GENERAL_INFO.htmlWork shop manualshttp://www.4shared.com/document/EJG4a0P1/CONTENTS_157W-4-1_.htmlhttp://www.4shared.com/document/VJ1mx-EB/engine_and__acessorieW05.htmlhttp://www.4shared.com/document/0l-mi4U3/engine_and__acessorieW05_2.htmlhttp://www.4shared.com/document/ZkAPDc2C/FRONT_ATTACHMENT_CONTENTS_157W.htmlhttp://www.4shared.com/document/0IuD0gJI/GENERAL_INFO_CONTENTS_157W-1-1.htmlhttp://www.4shared.com/document/jk113ozJ/GENERAL_INFO_CONTENTS_157W-1-1.htmlhttp://www.4shared.com/document/Kmykcsow/UNDERCARRIAGE_CONTENTS_157W-3-.htmlhttp://www.4shared.com/document/aBu8B2AC/UPPERSTRUCURE_CONTENTS_157W-2-.htmlParts Manualshttp://www.4shared.com/document/b1LsOUVF/CATALOG_EX200-3_LC_H_PARTS_CAT.htmlhttp://www.4shared.com/document/Vr8O0gLI/EQUIP_COMP_EX200-3_LC_H_PARTS_.htmlTry these

I am interested in Hitachi EX120-3 manuel

tarzanWhich manuals were you looking for the 120-3 operation ,parts or service.

Hitachi EX 120--3Not sure, I need to know the wiring diagrahm for the # 7 fuse VAL.c/u keep blowing a 1 amp fuse. I have already replaced the computer.

thats the PVC fuse.you have a short circuit wiring or short circuit sensors.check your angle sensor.if the angle sensor is not set properly or you have an bad angle sensor it will keep blowing the fuse no. 7.

where is this located, the code on the fuse says val.c/u

it is located on the side of the main pump. its a can shape sensor.

give me your email address ill send you the component location.

Thanks, will check this out!!!

[email protected]THANKS!

Tarzan,Whatever you do DO NOT put a higher than 1 amp fuse in there, you will cook your computer if you do! Don't ask me how I know this. On my EX200-2 there were a few issues, I don't know how to post a link to my EX200-2 electrical problem thread but I've got what I found for problems in there. The long and short was that the wiring harness was toast, it had shorts, open circuits and all kinds of other issues so I replaced the entire wiring harness. (By the way rgl726 I haven't forgotten about getting you that info, I just haven't had time to find it yet, sorry. I promise to get it to you as soon as I can) The alternator was also putting out in excess of 36 volts, so make sure yours isn't pushing too much power in there, it does bad things! What I would suggest is to disconnect every sensor and solenoid one at a time, and see if the fuse still blows. Be sure to switch all power OFF BEFORE disconnecting or reconnecting anything. Once you unplug something and it doesn't blow the fuse you've found your culprit component. If it's a short in your harness the fuse will still pop once everything is disconnected... Hope this helps a bit, keep us posted. Good luck!

Try if you can find a resetable circut breaker if will save you some money and time replacing the blown fuses every time while testing.

hello, i am new to this site and also a new owner of an 120-2 that i bought off an auction. here are my troubles for the past 4 weeks, the engine is in great shape but it was having trouble crawling and couldnt move up on an incline. when the unit gets hot the hydraulics stop working. was able to fix by fixing the upper computer box, had the main pump and travel motors cleaned. the only problem left is that the hydraulic oil gets really hot after 40 minutes of operation. i have consulted two technicians and they both agree its the computer box - the lower one which controls the hydraulics has a burned part but it was burned so badly we cant identify it to have it replaced. can somebody help me - maybe a snapshot of a computer box or where can i buy a new one? thanks

hi sir where is your unit located?how did you diagnose that its the computer box (EC if you are reffering to upper box)?I can supply you both computer box but you need to have a proper diagnostic.

hi, my unit is in san juan metro manila.it is the lower computer if i am not mistaken it is the EPC?may i know how much it is if you have it?thanks

... i had a technician diagnose the computer and solenoids. the upper one (EC) was already repaired so i had good power to the travel motors.bottom computer EPC get too hot plus the hydraulic oil gets too hot too.

You can contact me at 09173232700.

Good luck

I also have an EX120-2 that's getting hot after running and I get a clicking noisefrom the pilot hosescoming off the pump to the pilot filter. I have sealed solonoids which made no difference. Wiring looks good. I'm losing some power when I try to do multiple functions. Any ideas?

pemolitor said:I also have an EX120-2 that's getting hot after running and I get a clicking noisefrom the pilot hosescoming off the pump to the pilot filter. I have sealed solonoids which made no difference. Wiring looks good. I'm losing some power when I try to do multiple functions. Any ideas?Click to expand...try to replace your DP sensor with a new one.pilot pulse is normal in this machine

I work with Hitachi Ex120-2, the machine gets slow 30 mins. of operation specially swing and tracks. The hydraulic oil gets hot. Anybody can help me? Thanks...

Check your pilot pressure. It must be at least 700 psi

Thanks for your advice... I will try it.

DP sensor is $900. Anyway to test this. I have no codes in the computer. I did notice it it happens mostly while trying.to swing. And its not pilot pulse. Its more like a clicking or clunking. Like a pump or valve turning on and off in the pilot system.

Check swing pilOt pressure sensor.

3Doc do you have ainstructions for putting new PPC valve (pilot control valve in a ex 120-2 digger they are the ones in the stick controls cheers Brent

Welcome to the forum kuriwao. :usaAre you asking for advice replacing the PPC valves, or installing new seals in the PPC valve?

I am going to buy a set of ppc valves and I was just wanting to know the proseduare tp put them in thanks for asking

If you're replace the entire PPC valve assembly, it's pretty easy, ports are marked on the bottom. Just make sure you don't switch the location of the fittings, sometimes they are different. If you are just replacing components of PPC valves, would help to know exactly what you're planning on doing.In either case, the most time you'll spend will be getting the consoles apart on left and right and getting the PPC valves out. Kinda cramped and tight quarters inside the cab of an ex working on those things.

I was just wanting some instructions and a picture of all the things that might come out and bite me and get lost some where in the cab thanks for your reply cheers Brent

Well, if you are simply replacing the entire PPC valve unit, not much will go awry. But, very important, mark the orientation of the valve, how it's mounted, like Front Side. If you turn those things just one quarter turn upon re-install, it's not going to work proper. And make certain you don't switch around the fittings in the bottom of the PPC valve where hoses connect, sometimes those fittings are different.Aside from that, It's just a matter of removing console panels and such to get to the valve to service it. Be sure and remove the joystick handle from the PPC valve stem before removal, just easier to do when it's mounted solid in the framework of console. You'll have to disconnect wire that goes to horn button or throttle button so you can spin the handle around and unthread.If you're going to take the PPC valve apart to reseal, then there are a number of gizmos that can go flying to parts unknown. Here's a thread that shows what's inside those things. This from a Case 9050B, but these things are very similar is design and setup.https://www.heavyequipmentforums.co...g-a-leaking-joystick-control-valve&highlight=

kuriwao said:I was just wanting some instructions and a picture of all the things that might come out and bite me and get lost some where in the cab thanks for your reply cheers BrentClick to expand...the easy way for this is to remove the cab

I have a question regarding the hitachi ex 120-3 i bought the dr.zx for it n i can't find the connection for it i located one where the dash it but im unable to connect or make connection i sometimes get connected to icf thats about it can i get a pm from someone who knows how to use the dr.zx palm thanks

i have an ex 120-2 machine, it gets slow after 40 mins of operation especially traks and swing. i need help, thanks..

Thank you for your help rgl726. I Took the machine to the local Deere/Hitachi shop and had them run diagnostics on it...They determined that the pump or the manifold has an internal leak. The pump is new so I'm guessing it's the manifold. I need to find a new manifold or rebuild the existing one. The guys at the shop suggested against rebuilding. I'm running it with the dp sensor unhooked to get me by till I can find parts to fix it. Will this hurt the machine? It runs well like this just smokes a little more.

pemolitor said:Thank you for your help rgl726. I Took the machine to the local Deere/Hitachi shop and had them run diagnostics on it...They determined that the pump or the manifold has an internal leak. The pump is new so I'm guessing it's the manifold. I need to find a new manifold or rebuild the existing one. The guys at the shop suggested against rebuilding. I'm running it with the dp sensor unhooked to get me by till I can find parts to fix it. Will this hurt the machine? It runs well like this just smokes a little more.Click to expand...I have the same problem you experienced pemolitor. There is a clicking noise in the pilot hose and the machine loses power when doing combined functions. Which pump did you say had the leak? The pilot pump or main pump?

My pumps are new. We think its in the manifold. I'll know more next week.

what manifold is this exactly? i guess u mean the main control valve

Yes, the main control valve.

i have a machine ex 120-2, the arm extension is out of control, sometimes no movement, i check the solenoid valve, its sticking, i need help, thanks in advance.

Great site! i bought an ex120 and only after getting it home discovered it would bind up after 20 min. i did extensive reading on this site and swapped the displacement solenoids.that did not help so i felt i had a sensor problem and decided to to have a deere expert check it. diagnostics showed a bad angle sensor. after a quick r/r she running great!my thanks to all. keep on digging

have you found a solution pemolitor?

pemolitor said:Thank you for your help rgl726. I Took the machine to the local Deere/Hitachi shop and had them run diagnostics on it...They determined that the pump or the manifold has an internal leak. The pump is new so I'm guessing it's the manifold. I need to find a new manifold or rebuild the existing one. The guys at the shop suggested against rebuilding. I'm running it with the dp sensor unhooked to get me by till I can find parts to fix it. Will this hurt the machine? It runs well like this just smokes a little more.Click to expand...the symptom of bad or unhooked DP sensor is hydraulic hissing. because the pump keeps on banking even without demand or sticks in neutral.

pemolitor said:My pumps are new. We think its in the manifold. I'll know more next week.Click to expand...Pemolitor have you discovered the problem or found a solution yet?

Andre-1 said:Pemolitor have you discovered the problem or found a solution yet?Click to expand...I haven't found the problem yet. I've just been running with the DP sensor unplugged.

pemolitor said:I haven't found the problem yet. I've just been running with the DP sensor unplugged.Click to expand...I found the problem. The pressure in the pilot system and on the compensators was low. correct values 512+/- 15 PSI pressure reducing valve, 750 + 140- 0 PSI for Pressure on arm out pilot cap. these are for a 490E excavator. try teeing into the line from the pressure reducing valve and the arm out pilot cap line and check the pressure. I added shims in both the pressure regulating and pressure reducing valves to increase the pressure as needed.

Can you post pictures? I'm not sure were all the components are as I don't have a manual.

pemolitorI can email you a manual if you need it.What dash number is you machine?Do you need a parts and service manual.

TOOL KINGI sent you a PM , do you think you can help me out with my EX40UR? Thanks JIM

TOOL KING. I could use both manuals. I have a -2 machine. I will send you a pm with my email

pemolitor said:Can you post pictures? I'm not sure were all the components are as I don't have a manual.Click to expand...did you get the manual or do you still need the pics?

Andre-1, tool king's mailbox was full so I didn't get the manuals yet. I could still use the pics. I really appreciate the help. I've spent a lot of money to have this diagnosed with no luck.

ex120-2 service manual and parts manualI am interested in Hitachi EX120-2 manual if anybody have the copies please e-mail me as I really need it for my machine troubleshooting and repair. stuggle to repair it since five month ago.my email adress:[email protected]or[email protected]

pressure reducing valveLocation: open door on cab side next to radiator and oil cooler, remove air cleaner and the valve is directly in front of you. it has 7 solenoids on it and two valves: pilot pressure reducing valve and pilot pressure regulating valve.pilot pressure reducing valve is the shorter valve on the extreme right. The pilot pressure reducing valve is used to set the point at which the different applied pressures start to move the flow compensator valves. this is important for combined operations. setting should be 512 +/- 15 PSI. pressure may be increased by adding shims.

athis is on the main control valve, looking from the front of the valve/ machine it is the second pilot cap from left to right. this is where you test the pressure in the pilot circuit. this pilot pressure is regulated by the pilot pressure regulator it is the taller valve on the pic showing the pilot pressure reducer, the reducer is the shorter valve where the gauge is shown attached. both contain spring and spools and shims to set the pressure. regulated pressure should be 740 + 140 - 0 PSI when you operate arm out function. engine should be at max power, hyd temp around 50 degrees Celcius , autoidle off,work mode in general purpose. Rememebr this is for a 490E Deere. not sure if the same specs for the hitachi 120. Private message me your email so i can send you better pics and some extracts.

pemolitordownload these links .The tech schimatic drawings and workshop are for dash 5 but should help out .schimaticshttp://www.4shared.com/document/04JXvgIx/01_ELE1.htmlhttp://www.4shared.com/document/CYc8OTum/02_ELE2.htmlhttp://www.4shared.com/document/HDhNxApy/03_CON1.htmlhttp://www.4shared.com/document/g57IuxEN/04_CON2.htmlhttp://www.4shared.com/document/zenNzBVO/05_ENG.htmlhttp://www.4shared.com/document/KXB63oeG/06_CAB.htmlhttp://www.4shared.com/document/KBwHw99h/07_RELAY1.htmlhttp://www.4shared.com/document/o_FIKpER/08_RELAY2.htmlhttp://www.4shared.com/document/3zfJYy--/09_AC2.htmlhttp://www.4shared.com/document/naiymPBf/10_AC1.htmlPartshttp://www.4shared.com/document/fBKNvIVx/CATALOG_EX120-2_PARTS_CATALOG.htmlTech manualhttp://www.4shared.com/document/IluTD0G5/COMPONNT_OPERATION__CONTENTS_1.htmlhttp://www.4shared.com/document/PnISQRWS/GENERAL_CONTENTS_155T-1-1__3.htmlhttp://www.4shared.com/document/RiHwZklF/PROFORMANCE_TEST_CONTENTS_155T.htmlhttp://www.4shared.com/document/5WkPRWp9/SYSTEM__CONTENTS_155T-2-1__2.htmlhttp://www.4shared.com/document/Ku0DI-8A/TROUBLESHOOTING_CONTENTS_155T-.htmlhttp://www.4shared.com/document/xdGNqzFg/INDEX_3.htmlworkshop manualhttp://www.4shared.com/document/ZJ-tvBQN/ENGINE_AND_ACCESSORIES_W05_2.htmlhttp://www.4shared.com/document/wwKxyuB4/FRONT_ATTACHMENT_CONTENTS_155W.htmlhttp://www.4shared.com/document/soJ-uhvN/general__155W-1-1__2.htmlhttp://www.4shared.com/document/HbvEfdTJ/undercarriage_155W-3-1__2.htmlhttp://www.4shared.com/document/jq4ioR3L/upper_structure_155W-2-1__2.htmlhttp://www.4shared.com/document/EZUOQK_8/INDEX_4.htmlHopefully these help you out.Let me know when you download them.to make sure you got them all.thanksED

dakuchI do not have the manual for your machine.But their is website that sell manuals for all kinds of machines.They are retty good on prices .I will send the web address to you.thanksEd

Pemolitor I checked it out, it appears the ex120- 2 and 490e are built the same. so the same specs should apply. I have some extracts from the manual I can send you via email

tool_king said:pemolitordownload these links .The tech schimatic drawings and workshop are for dash 5 but should help out .schimaticshttp://www.4shared.com/document/04JXvgIx/01_ELE1.htmlhttp://www.4shared.com/document/CYc8OTum/02_ELE2.htmlhttp://www.4shared.com/document/HDhNxApy/03_CON1.htmlhttp://www.4shared.com/document/g57IuxEN/04_CON2.htmlhttp://www.4shared.com/document/zenNzBVO/05_ENG.htmlhttp://www.4shared.com/document/KXB63oeG/06_CAB.htmlhttp://www.4shared.com/document/KBwHw99h/07_RELAY1.htmlhttp://www.4shared.com/document/o_FIKpER/08_RELAY2.htmlhttp://www.4shared.com/document/3zfJYy--/09_AC2.htmlhttp://www.4shared.com/document/naiymPBf/10_AC1.htmlPartshttp://www.4shared.com/document/fBKNvIVx/CATALOG_EX120-2_PARTS_CATALOG.htmlTech manualhttp://www.4shared.com/document/IluTD0G5/COMPONNT_OPERATION__CONTENTS_1.htmlhttp://www.4shared.com/document/PnISQRWS/GENERAL_CONTENTS_155T-1-1__3.htmlhttp://www.4shared.com/document/RiHwZklF/PROFORMANCE_TEST_CONTENTS_155T.htmlhttp://www.4shared.com/document/5WkPRWp9/SYSTEM__CONTENTS_155T-2-1__2.htmlhttp://www.4shared.com/document/Ku0DI-8A/TROUBLESHOOTING_CONTENTS_155T-.htmlhttp://www.4shared.com/document/xdGNqzFg/INDEX_3.htmlworkshop manualhttp://www.4shared.com/document/ZJ-tvBQN/ENGINE_AND_ACCESSORIES_W05_2.htmlhttp://www.4shared.com/document/wwKxyuB4/FRONT_ATTACHMENT_CONTENTS_155W.htmlhttp://www.4shared.com/document/soJ-uhvN/general__155W-1-1__2.htmlhttp://www.4shared.com/document/HbvEfdTJ/undercarriage_155W-3-1__2.htmlhttp://www.4shared.com/document/jq4ioR3L/upper_structure_155W-2-1__2.htmlhttp://www.4shared.com/document/EZUOQK_8/INDEX_4.htmlHopefully these help you out.Let me know when you download them.to make sure you got them all.thanksEDClick to expand...Tool king I think pemolitor has the ex120-2

Andre-1I figure any information is better than none when you are in bind.Can you email those extracts that you have for the 120-2 and 490E .That would be awsome to have the info.My email is[email protected].Please feel free to download the links I posted for yourself.thanksED

Tool king, Andre-1, thank you for all the info. Hopefully this helps me fix what was told to me to be unfixable. Andre-1 pm sent.

pemolitorWhat is the problem that they can not be fixd?

My 120-3 is having a similar problem, travel and boom functions are extremely slow. Dipper and swing seem to be ok. Anyone have any ideas?

tool_king said:pemolitorWhat is the problem that they can not be fixd?Click to expand...I shouldn't say can't be fixed..... they just want me to throw $10,000 parts at it and hope it solves the problem. That just under half the what I paid for it. All the can tell me is I have an internal test without doing and pressure test.

looking for a manual for ex 120 -2

nolap the manuals toolking posted on page 13 of this thread are pretty good.the parts one is for the ex 120-2 the others are for the ex 120-5 which is very close.thanks toolking

nolap said:looking for a manual for ex 120 -2Click to expand...I have the workshop manual, technical manual and operators manual for this machine.

nice to see back on the thread -3Doc.long time no see.

3DocWould you mind sharing the workshop manual, technical manual and operators manual for the ex 120 -2machine. My email address is[email protected].Please let me know if you have any other manuals to share .I have a lot of manuals to share too.THANKSED

rgl726 said:nice to see back on the thread -3Doc.long time no see.Click to expand...Been very busy fixing broken machines!!

Send me a pm we will talk!!

I would be very interested in these manuals also.My email address is[email protected].Thanks nolap

Hi all .I would like learn the Excavator Hydraulic pump testing system, and where can get any manual ,documents for it.Please let me know and share to me .Thanks.

MyOn my itachi, I had a seized cable. I stripped the covering and called it good...Also the banjo filter is a culprit.

Hello Sripola, My name is Srini from India. I have HITACHI EX120-3 and encountering same prob.I replaced PVC and Pump solenoid valves.Still same problem. Boom and tracks are not working past.very slow. could u pls help me.Could u pls send me wiring diagram for this machine.My email:[email protected]. Thanks,

Check the variable pressure compensator valve on the pilot system

HITACHI EX120-3 circuit diagramHello 3Doc, could you please email me of HITACHI EX120-3 CIRCUIT DIAGRAM?Please.

hitachi ex120-2 pump angle sensor checking and proper settingneed advice on how to check pump angle sensor and proper adjustment of that sensor. Anybody have the procedure please help me...........

I have an EX120-2 and am trying to dismantle the final drive. She has munched the gears on the inner planatary drive. I have been able to get the first 3 gear planatary assembly off but dont know how to get the inner three gear assembly out. The final drive is still attached to the excavator. Can any one help?

hello and welcomehere's a final drive from an ex120-1you need to remove the casing next (top of picture)if you look close inside you can see the 'step ' to the inner teethcrack the seal of the gasket before fully removing the last bolt, watch your feet

Please send 120-2 manuals to[email protected]I have the issue with engine dying under any hydraulic load.Does the fluid level usually remain the same in the tank if the control valve is working and allowing the fluid to return?We have cleaned fuel side filters/strainers and still have power/stall. Is there a filter in the fuel injector pump?Thanks!

Not a 100% on the smaller units, but the bigger with the Isuzu engines there is a metal screen on the banjo bolt at the injection pump coming from the filter housing output side. I usually pull the banjo bolt and remove the screen retainer(slotted) and then clean with brakeclean and compressed air. Most have issues with acceleration as well as low RPM under load if that screen is at fault. If that isn't it let me know and we can move onto the next step.

Fuel is not the problem.Went through all fuses and replaced with new/correct ratings and now major changes. Everything seemed to work except the cab would not swing in either direction. I pulled fuse 14/stop M and cab would swing for a few seconds and then stop. Pulled out fuse 7 and everything seemed to work but travel was slow and things started to act up again and stall after a few minutes.Replaced fuses and pulled duct cover and both boxes had led blinking slowly.Found a set of wires that had been patched to bypass a relay but don't have manual to determine what they were and how to reconnect to relay. The relay was on the side next to door closest to front.Four wires with black/white, green/whit, blue/white, and white with a red circle? Would appear someone had bypassed something and now that all fuses are in the problem has been isolated to something that keeps cab from spinning left or right.I am new to this and a probationary member and not sure how to properly request the manuals so I can trouble shoot properly.Thanks!

Does anyone have the part numbers for the screens/strainers that go in the banjo fittings? I downloaded the 120-2 parts document and am having trouble finding them in the fuel or engine sections. Also, I could use the shop/service manuals if anyone can provide.At this time my 120-2 runs great when you first start and everything works initially. After running a while, which does not seem to be time and/or heat dependant, the swing becomes erratic and works only occasionally.It appears that when the swing motor is not working the other hydraulics are more jerky in motion and not smooth. If the swing starts to works the other motions become smooth again. Plenty of power and the travel responds to the tortoise/hare settings.Thanks for any ideas/help.

HITACHI EX120-3 Hydraulic sysyetm failure and heatHello -3Doc,It is1994 HITACHI EX120-3 . The machine is overheating after about 20mins of working. Both engine and hydraulic oil were getting very hot and I was unable to touch Hydraulic Tank since it is very hot. As soon as getting heat, Boom, track and all other Hydraulic parts became very slow ,even couldnot lift boom. I replaced PVC controller and Two High Speed pump solinoids with new. Still same problem. Please help me in this regard. My Electrician and Hydraulic mechanic have been struggling since 2 months, but unable to fix it.But engine side first 20 min some times legging problem otherwise engine side all perfect, no black smoke.My electrician carefully reviewd all wiring connections. Please send me wiring diagram for this HITACHI EX120-3 to my email id:[email protected]. And also tell me the procedure to test N-Sensor, A-Sensor, P-Sensor and DP-Sensor. Please take me out from this soup.I am ready to pay for your service.I don't know how to PM. Please reply.Thanks in advance.Srinivas Eadara+91-9848284123+91-9246284123

HI I have an Hitachi EX100-2, which every so often will not lift the main boom, slew or track, but it will crwd and tip the bucket and cycle the dipper. But if you slew slightly before lifting the boom, the boom lifts as normal, but still wont track.The fault never occurs when digger is cold or 'warming up'.This is a totally random, and intermitent fault without any timetable, it might dig there again it might not!! When its running normally, all services and fine, and the machine has plenty of 'dig', definitly not a failing pump problem.The pilot filter housing gets very very hot to touch within a short space of time, but this does not affect digging when machine running properly. The oil cooler is clean with air flow going through it properly, there is no debris in any of the hrdraulic filters(pilot circuit, suction or main).All digging and track modes work fine when digger normal, but I can tell when the digger is going to throw a fit, because the services hesitate before responding, and you cant control the bucket as normal.Then just to confuse matters, the digger will start stalling whenever you move a service.This must be a swash plate thing.Has anyone any ideas as how i could linp digger back home?I have tried various things that seem obvious to check,The Outer 'o'ring went on the DP sensor, which I replaced, along with the other two 'o' rings and the plastic washer further down the sensor.(The DP sensor has beem disconnected ever since I had the digger)(Cleaned out the screen in the banjo fitting.-Changed the fuel filter (didn't change anything)-Checked the fuses, check harness wires in pump bay, and replace any dodgy connectors.cheersRichard

you have a thermal failure of the angle sensor.if this sensor fails thermaly you can work for 30 min to an hour and the failure will occur right?

ex100-2HI Thanks for the replyYes this was origionally exactly correct.But yesterday the origional problem cleared and she worked for about three hours, then started stalling when any lever was pulled.Now even from cold up to working temperature, the digger will stall.Richard

the angle sensor is now busted.try to replace the angle sensor first.be sure to configure it properly.

OK thanks very much for your help.Can I replace the sensor without removing the main pump from the machine?If so, will i be able to line it up properly in situ?Also is there any way of lying to the angle of the swash plate to enable me to limp machine back to my workshop? at the moment its in a field away from home!!!do you think its significant that the DP sensor has been disconnected before I bought the machine?Richard

Ouch!! angle sensor is £400.can you get non genuine ones?!?!?!?!

Richardatwinder said:OK thanks very much for your help.Can I replace the sensor without removing the main pump from the machine?If so, will i be able to line it up properly in situ?Also is there any way of lying to the angle of the swash plate to enable me to limp machine back to my workshop? at the moment its in a field away from home!!!do you think its significant that the DP sensor has been disconnected before I bought the machine?RichardClick to expand...my technique is removing both wires of the 2 pump soleniods. just make the pilot commands easy(push very little on the controls) because the pump will be at full swash. this way you can load it to a selfloader.disconnecting the DP sensor is not a good idea.its ok to use non genuine as long as you can hit the right one.sooner or later you'll get use to the prices of this parts.

Richardatwinder said:OK thanks very much for your help.Can I replace the sensor without removing the main pump from the machine?If so, will i be able to line it up properly in situ?Also is there any way of lying to the angle of the swash plate to enable me to limp machine back to my workshop? at the moment its in a field away from home!!!do you think its significant that the DP sensor has been disconnected before I bought the machine?RichardClick to expand...You need the manual to replace the sensor and set the voltage properly. You can put the machine into a limp mode in order to get it home. If you look on the bottom of bothe pumps there is a four bolt cap plate over the end of the swash cylinder pistons. If you remove that plate you will see that it has a peg sticking up from the underside of the plate, if you turn the plate 90 degrees and replace it back in the hole then the pin will put the pumps into about halve swash and they will stay there the you can get the machine home if you feather the controls. As for your problem it sounds to me like the pump displacement solenoids, they tend to work fine when cold but as the machine heats up the coils break down and they quit working then the machine goes to full swash and stalls. Good luck.

Hi againI do have all the workshop,tech and parts manuals for this digger, but I am hoping the guy I purchased if from will be in charge of repairs, when he returns from holiday.Is there any thing else on the EX100-2 machines that i should be wary of? I had heard that the ex100-3 were a bit unreliable, and I couldnt afford a ex100-5She has done 7000 hrs, there is no rock in slew ring at all, tracks are ok. A little slop in the main pins, but not much.Is the slew dampering valve on the bottom of the main boom supposed to click?Will she be ok without a DP sensor/or Should I get it re-wired back in? its probably bust in the first place, which is why its been removed!!!many thanks againRichard

Hi AgainI looked at the plate under the pump that you said to rotate by 90 degrees to move the swash plate to half, the plate is oblong, so I cant turn it through 90 degrees, 180degrees yes, 90 no!!!Any more ideas??Richard

You need to pull this plate straight down, it has a long finger on top of it. Once you have it pulled all the way out turn it 180 degrees then shove it back in. This will push the swashplate piston up and destroke your pumps to limp mode. You may need to undo the small hydraulic line on the top of the pump to relieve the pressure in there to be able to push the piston up. At least that's how it works on my 200-2, I imagine yours would be similar or the same...

HITACHI EX120-3 Angle Sensor setupHello -3DOC, Could you please help me in setting Angle Sensor ? I need manual and voltage setup procedure. Please.

seadara said:Hello -3DOC, Could you please help me in setting Angle Sensor ? I need manual and voltage setup procedure. Please.Click to expand...send me a PM and we will talk about manuals.Thanks Doc.

I have read all of the threads that have anything to do with the HITACHI 200LC. I have checked fuses, computer is operating normallyOut of the 4 sensors they all tested fine. ALTHOUGH the angle sensor was a little suspect.STEP 1: I removed the sensor and checked with a small screwdriver to see if the fork on the swash plate was intact. I could rotate the fork freely which indicates that one of the arms must be broken.STEP 2: I put my multimeter in parallel on the ground and sensor return wires and adjusted angle sensor to roughly 1.45 or 1.54 Volts which is where it should sit in normal operation ** (I may not be accurate with the set voltage values because it has been several months since doing this but a guy with lots of experience had told me to set it to this so I am not making this number up) ** I then reinstalled the angle sensor.STEP 3: I got a friend to start the machine and operate it while I monitored the voltage.....WHAMMO the machine ran awesome no stalling or slow operation.THEN.. the voltage changed and the machine acted up again. **( I cant remember which did what but from what I gathered after a few tests. Either when the voltage goes above or below the value that I had originally set it causes one of these two things.ISSUE 1: the machine goes into a limp mode where the engine is at high rpm but all the hydraulic functions are slower than molasses.ORISSUE 2: the machine runs fairly normal except it will stall out when you run the hydraulics full out (two functions at the same time or fully extended or retracted)My question to anybody is. Has anybody had this problem before? What have they done to fix it? Is it possible to tear down the pump and replace the fork? Does anybody have a rebuilt pump? Is there a manual that shows step by step instructions for tearing down the pump?Or is my troubleshooting completely effedand I am so far out I should get my head checked?

000496519 said:I have read all of the threads that have anything to do with the HITACHI 200LC. I have checked fuses, computer is operating normallyOut of the 4 sensors they all tested fine. ALTHOUGH the angle sensor was a little suspect.STEP 1: I removed the sensor and checked with a small screwdriver to see if the fork on the swash plate was intact. I could rotate the fork freely which indicates that one of the arms must be broken.STEP 2: I put my multimeter in parallel on the ground and sensor return wires and adjusted angle sensor to roughly 1.45 or 1.54 Volts which is where it should sit in normal operation ** (I may not be accurate with the set voltage values because it has been several months since doing this but a guy with lots of experience had told me to set it to this so I am not making this number up) ** I then reinstalled the angle sensor.STEP 3: I got a friend to start the machine and operate it while I monitored the voltage.....WHAMMO the machine ran awesome no stalling or slow operation.THEN.. the voltage changed and the machine acted up again. **( I cant remember which did what but from what I gathered after a few tests. Either when the voltage goes above or below the value that I had originally set it causes one of these two things.ISSUE 1: the machine goes into a limp mode where the engine is at high rpm but all the hydraulic functions are slower than molasses.ORISSUE 2: the machine runs fairly normal except it will stall out when you run the hydraulics full out (two functions at the same time or fully extended or retracted)My question to anybody is. Has anybody had this problem before? What have they done to fix it? Is it possible to tear down the pump and replace the fork? Does anybody have a rebuilt pump? Is there a manual that shows step by step instructions for tearing down the pump?Or is my troubleshooting completely effedand I am so far out I should get my head checked?Click to expand...If you can turn the shaft in the pump easily were the angle sensor goes in, then that is your problem!! That shaft is hooked to the swash plates on the pump and should only move when they move. There is a small pin that holds the fork to the swash plate and that falls out causing your problem. If you are comfortable you can buy the gaskets and remove the pump heads and repair the problem, but you shoul have instructions or a manual. you must drain the hyd oil. PM me if you need manuals.Thanks -3doc.

-3Doc said:If you can turn the shaft in the pump easily were the angle sensor goes in, then that is your problem!! That shaft is hooked to the swash plates on the pump and should only move when they move. There is a small pin that holds the fork to the swash plate and that falls out causing your problem. If you are comfortable you can buy the gaskets and remove the pump heads and repair the problem, but you shoul have instructions or a manual. you must drain the hyd oil. PM me if you need manuals.Thanks -3doc.Click to expand...I have the service manual and parts manual but it is a hard to follow manual. Is there another manual that breaks it down into steps with torque specs out there that you know of. If so I'll take one of those for sure.

Anyone know a good place to get a replacement wiring harness for a EX100-2. mine is all cracked and the machine keeps having intermittent issues and blows fuses. I already changed the EPC and not looking to change an other one that soon.

TraxterMaster said:Anyone know a good place to get a replacement wiring harness for a EX100-2. mine is all cracked and the machine keeps having intermittent issues and blows fuses. I already changed the EPC and not looking to change an other one that soon.Click to expand...I bought mine for my EX200-2 at Wajax. Cost a few bucks but well worth it, no more issues now, machine runs like new!

good day 3Doc,I am in search of manuals and advice for a ex120.please contact me[email protected]

I am finally getting back to figuring out my machine. found 4 connectors off of the pilot silinoids not connected. need to find the wiring harness to hook them back up. tried the schematic from page 12 or 13 of this thread.... but i can't blow it uo enough to see.

Hello everyone, i have a Hitachi EX200LC that is having the a problem of one track being slower than the other> for about 1 hour the machine works fantastic however when she is running at temp is when it will start to get really bad, by the end of the day it will almost not move, all i have done so far was inspect fluid levels and for visual leaks... not sure if this matters at all but when i pulled the plugs to check the fluid level i noticed the slow side had a considerable amount of pressure build up compared to the other, not sure if that matters!!

Hi,I have bought a Hitachi Ex 35 but whitout main hydraulic pump, do you now what kind of pump fits on?

hello. i`m having too some issues with ex100-2. toasted pvc, and a lot of black smoke out of motor when try some functions. i think my problem is in the angle sensor, or the rpm sensor when i read this topic. it has burned some fuses too, including pvc fuse. cant go near the machine for over a week because of my work. could someone very kind person email me the instructions to idle the angle sensor? and maybe how to test it if its okay. my emal is santikko(at)offipalsta.com. any mechanic data and manuals around this issue is welcome. this topic is great!

Hey all , Im looking for information on the macinno system on my 2 ex 135ur-5's. The units both have slightly different versions of the system but other than the fault code reporting screens the systems are unusable.I'd like to disable the systems completely but information on the systems here in australia isnt redily available. Any help would be greatly appreciated.cheers KRIZ

Need a little help. i have a ex120-2, the wires got pulled out of the pigtail off of the pressure sensor on the bottom the pump. there is a red wire+, white wire-, and a red green. now, what wire plugs into what stud on the pressure sensor? I appreciate any help. thanks jackson

santikko said:hello. i`m having too some issues with ex100-2. toasted pvc, and a lot of black smoke out of motor when try some functions. i think my problem is in the angle sensor, or the rpm sensor when i read this topic. it has burned some fuses too, including pvc fuse. cant go near the machine for over a week because of my work. could someone very kind person email me the instructions to idle the angle sensor? and maybe how to test it if its okay. my emal is santikko(at)offipalsta.com. any mechanic data and manuals around this issue is welcome. this topic is great!Click to expand...Did you try unpluging your angle sensor and see if you can get the PVC fuse to stop blowing?

Scrapper said:Did you try unpluging your angle sensor and see if you can get the PVC fuse to stop blowing?Click to expand...no, i didn´t. machine is not mine, i was called to help after the box was toasted. hopefully my friend gets the old box work again, so then i can make some investigations with it. i have readen these topics around this problem now, and got a lot of more knowledge to fix it. i found also the instructions to idle the angle sensor, so i give you more questions after i have tried few things if they doesnt help. this unplugging angle sensor information is useful too, didn´t cross my mind before. sorry for typo:s, i don´t have so good english

If unplugging the angle sensor doesn't stop the fuse from blowing then start unplugging other sensors, switches, ect. to see if you can find it.Just keep a good supply of 1 Amp fuses on hand and don't replace the PVC fuse with anything bigger than a 1 Amp fuse or you will toast the box if it isn't already.

yes it is already toasted, its at my friend now so he tries to get it work again. i ordered few transistors from china, when we get them then i can start finding what has caused the problem. i think it is the angle sensor. and its possible that someone has replaced sometime the 1a fuse with bigger one, so the box has given the holy smoke. there was one transistor down, and the place named r1 component toasted so badly i had to find another box where i could spy what component it was. but its ok now, just waiting the components arrival from china.

Need instruction for setting angle sensor voltage ex120-2

weedwards said:Need instruction for setting angle sensor voltage ex120-2Click to expand...cheack out the tread hitachiex120/3 i had the same problem and there is a link how to set an angle sensor

dodgeram22871 said:cheack out the tread hitachiex120/3 i had the same problem and there is a link how to set an angle sensorClick to expand...Link to directions for adjusting angle sensor.https://www.heavyequipmentforums.co...em-Help-Please&p=186591&viewfull=1#post186591

Well you must get the pump to full stroke do you know how to do that?

Need instruction on how to check dp sensor ex-120-2Need instruction on how to check dp sensor ex 120-2

i would be interested too how to check the dp sensor, and really where it is located. okay, i know it is in main control valve, but i dont have an idea how is that translated into finnish properlypicture would give me more than a thousand words.

santikkothe sensor is screwed into the end of the valve and will have a three pin plug on it.

-3 DocCan you please email me a copy of the service manual for the EX120-2thanks[email protected]

guys,just a word of advise.............dont buy the cheap hitachi parts from China, over the past year i have bought loads of hi speed solenoids, angle sensors and DP sensors and they are rubbish. In the end just stuck to original Hitachi parts. The suppliers in China gave us some rubbish excuse like they have 2 factories and we were guaranteed the better quality parts but they are all the same. Not worth the hassle! But did buy a few PVC and EPC controllers and they have done ok so far. The most common fault i have found on these are busted DP sensors, not sure what causes it but have a feeling its the high temp. so have a look at that one first.

I'm having the same issue with my Hitachi 120 that a lot of people are having it seems. Hydraulics are killing motor under slight strain. The mechanics in this area are hopeless so I am trying to figure this out myself. It is not a fuel problem for sure. So I am troubleshooting hydraulics. I unplugged all sensors and it made no difference so somethings not working right. I ordered an angle sensor today to replace that. What should I check or test to find out what is wrong? Start at sensors? How and what after that? Thanks!

hey joel where in ms are you ?i live south of jacksonprob is most likely angle sensor or pump solenoid.check out this threadhttps://www.heavyequipmentforums.com/...-Ex120-Problem

hello joe! first, try to change the plugs between the solenoids on top of the pump. and you can test the angle sensor too, just unplug the two solenoids, then let the machine run at slow speed few minutes. you can hear when the pump reaches full swash. then plug a voltmeter + to the anglesensors middle wire, i remember it was black. then the - to the ground. you should see there 4,30volts. i saw in our excavator, that this was ok when motor was cold. after it gets warm, the a-sensor started to give very unstable power, like in a 30 seconds it went from 0 to 5 volts.i ordered an a-sensor from china, the first one went broke in a few ours, but i got new one from the seller, didnt have to even send the broken one back. now it has been working.if you have to change the solenoids and order them from china, you should first get it to parts and clean them up well. in my solenoids, i just plugged them and found out them sticking. i cleaned them up, and found there a very small metal particles which was left there after the machining. just take it parts, and flush well with brake cleaner or something else. after that they worket as new. it is not really so hard to find out how does the hydraulics work, only if you have problems with the wiring it gets ugly. or so i think, i dont like electric works

Jaytech, I am in Gulfport. I ordered a new angle sensor and will install it tmrw. Hope this works. I will test the voltage to the sensor, but I don't remember it making a noise like it was in full swash. I can't tell a difference from when it first starts to 10 or 20 minutes later. Is there anything I should be doing when installling the sensor or just put it in? I read on this post where you have to set the voltage.

I just saw the instructions posted. Thanks!

Do the -2's have a pvc controller? The -3s had a pump controller that always goes out on them

Yes the -2s have a PVC Controller.

check out the pvc fuse. its 1amp, and dont put there any bigger no matter how you want, you will get a toasted pvc in seconds. if its burned. when a-sensor gets really broken, it burns this fuse.

Hey could you recommend a chinese company where i can purchase a EPC controller for the hitachi ex120-2/ JD 490E excavator and how much did the ones you bought cost?

tarzan said:Not sure, I need to know the wiring diagrahm for the # 7 fuse VAL.c/u keep blowing a 1 amp fuse. I have already replaced the computer.Click to expand...Any idea where I can get an engine controller for the ex120-2/JD 490E excavator? Other than the dealer.

The led on my engine controller blinks rapidly in sync with rapid blinking of the leds on the speed controls and i can also hear the speed control relay clicking with the same speed. Water got inthe unit so i think its toast. Any idea if it can be repaired or where and how nuch could i get one for.

we fixed one which got toasted because of a too big fuse in pvc place, fixing it costed around like under ten dollars. you can open it and see if there is burned parts.

When your machine was cutting out, could you move the controls and nothing happen like the safety lever was pulled? This sounds like the same thing my EX200LC-2 is doing. It runs excellent when cold, but once it warms up it will start cutting out. I have to Idle the machine, then I can hear something release pressure like a valve opening or something. Then rev back up and it works fine until it cuts out again.Some days it is worse than others, seems to be worse on a hot day. I checked angle sensor and reset to 4.40 volts and still having same problem. It seems to do worse if I am really digging hard, boom up and stick in real fast at same time. Or when travelling. It seems to happen when you are demanding a lot of flow.tomex120 said:I narrowed down the problem with the ex120-2 cutting out when hot. It was the displacement solenoid valve, The electrical coil was crack and that was because the two oil seals behind the coil leaked and would slowly preasurize the electrical coil and expand it, then cutting out the coil circuit ( the coil is 18 ohms resistance) then the excavator would start to cut out. I fixed the seals and now its OK, but I would still like to replace the coil or solenoid. Does anyone have one ?Click to expand...

Looks like the same or similar problems with the 120's.I have tested all the suggested parts and still no luck.Has anyone had any luck with manual pump control?thank you

hey guys,Manual pump control is possible but the machine is not so quick or efficient any more. The -2's we've had have all had simmilar problems as above. The issue has most of the time been DP sensors. We bought several from China but these are C***. and go bust very very quickly indeed. The only things we got from China that have been ok are the PVC and EPC controllers, they seem to be ok. But for DP sensors, angle sensors, and high speed solenoids which what break on these machines just stick to OEM or you can get angle sensors only from Korea which are better. Korean angle sensors have been ok so far. Something i noticed on the chinese parts are that the DP sensor seals and coils are very very cheap quality and the seals cant handle the high temps. hope this info helps before anyone blows money on cheap copies!

we took one OEM angle sensor, and one from china. in both of them, was a blue sticker which said the manufacturer and it was the same. then i opened them, it had been done of a hitachi- marked components- both of them. i dont know is the finland- dealer just ****ing with us. but we have working chinaparts now. the first angle sensor broke down for some reason, but in 2 weeks we got new one from the dealer. solenoids didnt work at first, then i took them open and cleaned up. now they work.im not selling any parts my self, or dont even know anyone who does- im just angry for this finnish OEM seller, when we buy a 50€ part for over 600€ from them. i understand that you should get something on your pocket from selling those parts, but...

double post

Hello digfaster, i am having the same problem with my 1994 120-3. Did you ever figure out the answer? I have been reading some threads about the angle sensor, did you check this out on yours?

-3 DocHi. Do you still have any manuals for an EX120-2 ?We have just bought one at auction and needs a few things doing.Would appreciate any documentation for this machine. Operator's, service, parts, technical manuals, wiring diagrams etc.Send to: webdude at thewebdudes d0t com.Cheers, David.

Hi could I have a Manual for a EX 120

Mr 3doc, can i have workshop manual of EX 120 -3 please??cheers!

webdude said:-3 DocHi. Do you still have any manuals for an EX120-2 ?We have just bought one at auction and needs a few things doing.Would appreciate any documentation for this machine. Operator's, service, parts, technical manuals, wiring diagrams etc.Send to: webdude at thewebdudes d0t com.Cheers, David.Click to expand...If you got the manuals would you be willing to share them?I just bought one EX120-2 from auction to, and I look from manuals.Thanks. Val

Could you please pm me the info to test the sensors . Thanks.

-3Doc said:Sounds like the N sensor is not working, Check wiring to sensor on top of pump also known as the rpm sensor. Looks like a button held in with one bolt.Click to expand...I tested the wire on the N sensor and not getting 5 Volts to the power wire (white wire) , wire continuity checks out ok from connector at n sensor back to engine controller . This wire goes directly to the Engine controller. Seem like a faulty engine controller what do you think? Machine is a 490E Deere and a two wire n sensor.

I have an ex 120-2 that the swing and travel is extreamly slow! They will speed up some when you throw another function into relief . can anyone give me advice on what my problem is or where to start looking?

hi 3doc, I'm having problems with my 120 also . would you send me these schematic also?[email protected]thank you

tntdozer said:I have an ex 120-2 that the swing and travel is extreamly slow! They will speed up some when you throw another function into relief . can anyone give me advice on what my problem is or where to start looking?Click to expand...you should check the 2 solenoids on top of the pump

lucian said:you should check the 2 solenoids on top of the pumpClick to expand...I have swithed the wires on these solenoids with no change in the performance. I am looking at the proportional solenoids possibly being the problem?

3 Doc, you can send me the technical manual of EX120-2, i am reapair this machine.thanks

hey my ex120-2 is having same problem,dont really know where to start,i have installed a new rebuilt pump,that I bought ,the angle senser they sent on pump someone cut wires to short where it couldn't be used,so I took mine off my old pump, it like it just keeps stalling out under preasure,I turn angle senser one way and it has some function but under load in stalls out,turn it other way anf it will not do anything,i have cleaned fuel tank,blew out fuel lines ,replaced bad coupling to hyd pump,but I did mange to get it out woods to dry land, please I need help its costing me lost of down time. thks

1979april said:hey my ex120-2 is having same problem,dont really know where to start,i have installed a new rebuilt pump,that I bought ,the angle senser they sent on pump someone cut wires to short where it couldn't be used,so I took mine off my old pump, it like it just keeps stalling out under preasure,I turn angle senser one way and it has some function but under load in stalls out,turn it other way anf it will not do anything,i have cleaned fuel tank,blew out fuel lines ,replaced bad coupling to hyd pump,but I did mange to get it out woods to dry land, please I need help its costing me lost of down time. thksClick to expand...Hey. PM me your email address and I can send you the correct procedure for setting the angle sensor. It's important you set it correctly as it can give weird problems if incorrectly set.

Hey digger hunter it will not let me pm you but my email is[email protected]any help you can give will be much appreciated thankyou!

still having problems hitachi ex100-3Doc said:If you can turn the shaft in the pump easily were the angle sensor goes in, then that is your problem!! That shaft is hooked to the swash plates on the pump and should only move when they move. There is a small pin that holds the fork to the swash plate and that falls out causing your problem. If you are comfortable you can buy the gaskets and remove the pump heads and repair the problem, but you shoul have instructions or a manual. you must drain the hyd oil. PM me if you need manuals.Thanks -3doc.Click to expand...Hi 3doc I am having the exact same problem with my excavator I need to check the fork behind the angle sensor and it is not moving by hand. when I hook the ohm meter up I am only getting just under 1 volt. All fluids and any other possibly obvious problems have been check as well can you give me Any more suggestions

same problem...but at ex120-5......spunkeymonkey said:I made a mistake, it is an EX120-2! There is black smoke from the exhaust as the engine dies, this clears when the revs recover. Where is the swash plate angle sensor located?Click to expand...

-3Doc said:Here is a breakdown of your pump, the two solenoids are up on top, release the pressure in the hyd tank before you swap them.Click to expand...Hey can you send me this pic please? I cant see the numbers from here thanks[email protected]

ok...tq....my machine is ok when i release the pressure in the hyd tank...The small filter on cap hyd. tank is neede to change . ...tq..englis broken sory

[TEST] I bought a ex 120 not sure if it is a -2 are -3 I was told it was a -3 . there are no ser. # on frame are cab any one know how to find out . I am having a problem when I travel the motor slows down, but if I move ant hand controls rpms pick up and travel speeds up .

New to this; I was looking on e-bay and there is a conversion kit has anyone Install one and what is the pros and cons . I bought this machine for farm use clean ditches and remove some trees and later dig a pond. The machine is being used now but has some small problems the guy I bought the machine from just changed the computer out and has no change because it would not hold rpms had to keep hitting buttens .

Hi all, I have a problem with my 120-2 also, the step motor for the revs started making grinding noises the other day and it wouldn't rev up, I've put a new step motor on it now and it still won't rev up although there's no grinding noises now, is there anything else I should be doin? Could anyone help me out please

Wouldn't recommend the kit! It slows down the machine and your fuel consumption goes up as well!RAMATH98 said:New to this; I was looking on e-bay and there is a conversion kit has anyone Install one and what is the pros and cons . I bought this machine for farm use clean ditches and remove some trees and later dig a pond. The machine is being used now but has some small problems the guy I bought the machine from just changed the computer out and has no change because it would not hold rpms had to keep hitting buttens .Click to expand...

I fixed mineflyboyjoelms said:I'm having the same issue with my Hitachi 120 that a lot of people are having it seems. Hydraulics are killing motor under slight strain. The mechanics in this area are hopeless so I am trying to figure this out myself. It is not a fuel problem for sure. So I am troubleshooting hydraulics. I unplugged all sensors and it made no difference so somethings not working right. I ordered an angle sensor today to replace that. What should I check or test to find out what is wrong? Start at sensors? How and what after that? Thanks!Click to expand...1994 Ex120-2 Mine had a poor power problem as some others describe and oddly enough it was intermittent. The engine RPM would stay up but the hydraulics would slow down, sometimes so badly that the machine wouldn't travel up a small incline even though the engine was wound right out. It turned out to be a fuel supply problem. A plugged up screen inside the banjo bolt that holds the fuel line from the tank onto the water separator. It was confusing since the engine wouldn't loose rpm and I knew the fuel filter was clean so I thought it was a hydraulic control problem at first but testing the DP sensor, angle sensor etc. produced nothing. When the engine is starving for fuel it dosen't drag down the engine rpm since the pump computer reduces the pump load on the motor to maintain the engine rpm as first priority. The banjo bolt screen should be removed & cleaned whenever the fuel filter is getting replaced. I pulled the screen out with a pick & blew it out with compressed air. I don't think it's a good idea to eliminate it since it catches the big chunks before the lift pump down low on the motor.One other problem I had a year ago was that intermittently the hydraulics would "lock up" as best I can describe it when I would swing or travel. I would be swinging and then bang!!! the swing motor would just lock up and everything would come to a violent stop, same with traveling. The fix was the 3 wire connector at the pressure sensor on the bottom of the pump. The wire insulation had receded back away from the connector leaving 1/2" of bare wire at the connector (difficult to notice with the oil & dust coating), when the carriage would move the wires would wiggle enough to arc across the wires & give a high pressure signal to the pump control mod, the mod. would then dump hydraulic pressure and everything would bang to a halt for a second then operation would resume as normal. I disassembled the connector & soldered in some new wire leads & it's worked reliably since.I'm just an auto mechanic playing excavator operator building a house for my family, I'll sell it when I'm done. Hope this helps someone.

I have an ex 120-3 having the same problem, sometimes it is really slow then it changes to way to fast. I unplugged the two controls on the top of the pump trying to test the swash plate angle sensor and the machine doesn't sound like it goes to full angle but it stalls the engine when any function is used then the voltage is .909 volts on the volt meter. need some help got any ideas?

I tried to adjust the swash plate sensor it only had .9 volts loosened the screws and moved it and the voltage doesn't change.so I took it off and moved it by hand and the voltage stays the same. so ordered a new one , does this sound like I found the problem?

how many volts should go to the angle position sensor ?

Hello rgl726 I need some of your help in solving some problems on a Hitachi ex200-2 machine, I have not seen you online but I am trying to create a way I can communicate with you if that's possible.Thanks in advance.

Hello Mhlak were you able to solve your problem I a have a similar problem I have two angle sensors and on numerous occasion they both giving readings like 2.37v to 4.10v and something .35v to .57v. I was only able to get 4.40 volts when I put the dot on the shaft facing the harness which is wrong.

What are your problems? I can help...

If you guys are already tired troubleshooting your machines.. contact me.. I can go to your place.. just buy me ticket.. ***** i've been fixing hitachi for years already.. i can repair ec and pvc.. depends on how deep the damage is.. i know how frustrating it is.. as i also have ex200-2 that i already solved.. and i can tell you these machines have different kinds of problem... not only the angle sensor, dp etc..

Hello auy_tong2 I will have to see what the budget will total in order for you to travel all this way to my island this wouldn't be cheap. my machine was total manual them I personally replaced all the electrical system on the machine. About four weeks ago I was clearing an area and suddenly there was this rough movement with the boom and arm cylinders so I decided to try replacing the original angle sensor with another oem sensor I have but just cant get it to read 4.40 volts. I don't know if it busted. I put the machine in limp and it work just slow which confirm that it an electrical problem.

Dot of the angle must face the engine side installing...try moving it forward and backward to check voltage movement... just get the most of the 4.40v you can get and thats it...daddieboy said:Hello auy_tong2 I will have to see what the budget will total in order for you to travel all this way to my island this wouldn't be cheap. my machine was total manual them I personally replaced all the electrical system on the machine. About four weeks ago I was clearing an area and suddenly there was this rough movement with the boom and arm cylinders so I decided to try replacing the original angle sensor with another oem sensor I have but just cant get it to read 4.40 volts. I don't know if it busted. I put the machine in limp and it work just slow which confirm that it an electrical problem.Click to expand...

If the voltage is moving your angle is ok... there is other problem to check

Hello auy_tong2 thanks once again yes the voltage of the angle sensor is moving but I just cant get 4.40 volts the range I am getting is 2.37 to 4.10 with the dot facing the engine as you said where it can bolt up. if I continue to rotate the angle sensor where I get the 4.40 volts I can't secure it the slot is in space it far away from where the bolt have to screw in. what could I do then.

Just set it to 4.10 its ok .. it will work.. important thing is it will change voltage..

Hey auy_tong2 I did that but as soon as I try to lift the boom the movement is jerky and a loud vibration noise coming from the valve bank. could this be the DP sensor despite its new

When it jerks.. its like a main pump problem to me or your charging pump. actually its very hard to troubleshoot here. Like i said ..it could be your main pump, charging pump, dp etc.. check your hydraulic tank screen if you can fins metal debris..

Better replace first your pilot and hydraulic filter

What are the symptoms

Hello auy_tong2 I have install all new parts in the hydraulic pump, new pilot pump, new pressure, speed, angle and dp sensors, new pvc and ec controllers new throttle motor and ec sensor and new complete harness. As I have mention before it was working then while clearing an area it started to have that jerky movement with the boom and arm cylinders and this vibration noise from the valve bank so I decided to change the angle sensor but I just cant it to read the 4.40 volts and the last time I set it at 4.10 volts and still if I try to lift the boom its jerky and there is the vibration noise coming from the valve bank.I now have it in limp mode where it work but just slow. which suggest to me that the hydraulics are ok and this seem to be electrical.

to troubleshoot the machine properly you need a dr. zx. because you will see all the sensors in the system function in real time.eg. pressure sensors, angle sensor, dp sensor rpm sensor. any of this sensor failure has the same symptoms.its either overall slow movement or the engine will stall during relief on any function.so maybe you are replacing the parts that are not broken.did you replace the pump solenoid?

If its your electrical, it should have stalled..black smoke at idle or no smoke.. slow movement...

When I start the machine yes it do smoke a little at idle and increases as I select the rev button.when I try to do a function it slow with rough movements, the engine rev slow down and at the same time the vibration noise from the valve bank.Now due to the fact that I cant seem to get the correct voltage from both angle sensor I have I was trying to understand and solved that area first in order torule out the angle sensor what should be the most likely next culprit I should look at.I have one new pump solenoid valve but no dr zx do you have one I can buy.

make sure you unplug both sensors on top of the pump while you set the angle sensor

when did you buy a new pvc. look and see if the red light is blinking if it is a late model pvc and the angle sensor is bad the light will not come onuntil you un plug the sensor.

hello mhlak the pvc was purchased about 16 months ago and yes both pvc and ec are blinking about one second apart. If one of the sensor gone bad shouldn't the controller show a fault code.I am trying to get me a dr.zx from Canada hope it work out.

Permanent fix for all -2 model hitachi excavators with hydraulic or fuel issues1.INSTALL A MANUAL REV CABLE.2.REMOVE EXISTING HYDRAULIC PUMP AND INSTALL A MANUAL HYDRAULIC PUMP(example for a ex120-2 pump replace with a pump from ex120-1)

oh I forgot please ensure your main relief valve is good.

-3Doc said:I can supply you with one if you are interested. Just PM me.Click to expand...sir can you send manual and schematics for hitachi EX120-2.my e-mail is[email protected]you

spunkeymonkey said:I have a Hitachi EX120-1. It started stalling when the hydraulic pump was under load. At the same time, the engine started to run hot, and the hydraulics became really fast. Various people have looked at it, one said the pump was u/s, so I took it off and took it to a pump specialist, who couldnt find anything at all wrong with it! I believe it is an hydraulic problem, rather than a fuel problem, because the engine recovers its revs straight away when you release the lever. At some time in its former life, a lot of wires to the pump had been cut, and rejoined by twisting together, the machine worked for many years like this. I have remade all the connections, and it has slightly improved how the machine works, you can at least dig now, although the engine still stalls when a ram goes to its full extension or retraction, as though the pump is at full swash. Has any one else experienced anything like this? All suggestions gratefully recieved!Click to expand...had the same issue with stalling under loadafter changing fuel lines, filter, rebuilding the fuel pump and hydraulic pump which did nothing to fix the issue what fixed it was a simple turbo replacement event though the old one was still in good condition with no oil leaks and air still blowing.replace your turbo and check it because after all the money spent trying to solve the problem a simple turbo replacement did the trick.

Good morning! Still happen to have the manuals for the Ex120-2? I have a -3 but it may help. My email is[email protected]Thank you,S

Hi Val,Did you ever end up getting the manual for your ex. Would you mind sharing if you did? Thx,

Hi Bigkit, Any chance you would still have the manuals for the 120-3? Thanks! Sean

Me to please![email protected]

understanding your problem senori It operates not controlled lap or sit in the pilot pressure pump

spunkeymonkey said:I have a Hitachi EX120-1. It started stalling when the hydraulic pump was under load. At the same time, the engine started to run hot, and the hydraulics became really fast. Various people have looked at it, one said the pump was u/s, so I took it off and took it to a pump specialist, who couldnt find anything at all wrong with it! I believe it is an hydraulic problem, rather than a fuel problem, because the engine recovers its revs straight away when you release the lever. At some time in its former life, a lot of wires to the pump had been cut, and rejoined by twisting together, the machine worked for many years like this. I have remade all the connections, and it has slightly improved how the machine works, you can at least dig now, although the engine still stalls when a ram goes to its full extension or retraction, as though the pump is at full swash. Has any one else experienced anything like this? All suggestions gratefully recieved!Click to expand...You may have a broken spring in your main pressure relief valve. Have you checked your pressures?

lennyHi guys,I'm looking at purchasing a 200- 2 fir a meagre price, this machine is in need of an overhaul. The electrical wiring is bad so I'm thinking I may have to change the harness and computer if I buy it, I learnt from the thread that wajax sells them but what about DP sensor,angle sensors and pump solenoids, can anyone direct me to a reliable supplier that they have bought stuff from,seeing a lot of stuff online but not sure who's reliable. I'D really appreciate some feedback. Please email me at[email protected]Kind regardsCheers!

Purchase conversion to kit to change EX120-2 from computer control to hyd. control, engine under excessive load. Need help on proper installation instructions.

Hey Weewards if you are ssking for the installation manual it supposed to come with, yes i do have. Here is my address[email protected]

Hey willie59 do you by chance know how to install a travel alarm on the Hitachi ex200-2 excavator

daddieboyWould you mind shareing that manual with for the conversion to kit to change EX120-2 from computer control to hyd.My email address is[email protected].thanksEd

Weedwards, please give us a review of that conversion kit when you get it sorted out. I'd really like to know how well the machine works with that done.

manualManual wanted for hitachi ex120-2 thanks. Email[email protected]

Hitachi EX-120/2If anyone has a service / repair manual for this machine, could you please email me a copy? Thank you.[email protected]

Hi,I have a similar problem with my HITACHI 120-2 Excavator. I was wondering if anyone had the Electrical and Hydraulic diagrams for this machine that they could shareRegardsTom

tommurphyWhat is you email address ?I have a service manual I can email you .

Hi Tool_KingThank you for the help on this,My email address is[email protected]RegardsTom

tommurphy73 said:Hi Tool_KingThank you for the help on this,My email address is[email protected]RegardsTomClick to expand...Manual emailed to you

Thank you. Much appreciated.

I have what I believe to be a 120-2. I have read almost the entire thread and have found a lot of great tips that I will try as soon as the weather clears. Would someone please email me the Manuel. I just purchased the machine a few months ago and have had nothing but problems. I found a lot of wiring disconnected, leaks and the biggest problem, it stalls out when putting much of a load on it. I believe it to be a "grey market" Hitachi, therefore I can't get any help from Deere.[email protected]

spunkeymonkey said:I have a Hitachi EX120-1. It started stalling when the hydraulic pump was under load. At the same time, the engine started to run hot, and the hydraulics became really fast. Various people have looked at it, one said the pump was u/s, so I took it off and took it to a pump specialist, who couldnt find anything at all wrong with it! I believe it is an hydraulic problem, rather than a fuel problem, because the engine recovers its revs straight away when you release the lever. At some time in its former life, a lot of wires to the pump had been cut, and rejoined by twisting together, the machine worked for many years like this. I have remade all the connections, and it has slightly improved how the machine works, you can at least dig now, although the engine still stalls when a ram goes to its full extension or retraction, as though the pump is at full swash. Has any one else experienced anything like this? All suggestions gratefully recieved!Click to expand...Try the regulator valve on the pump if it's worn the the pump won't regulate the flow and will cause the engine to die?

tool_king said:3DocWould you mind sharing the workshop manual, technical manual and operators manual for the ex 120 -2machine. My email address is[email protected].Please let me know if you have any other manuals to share .I have a lot of manuals to share too.THANKSEDClick to expand...Did you ever get the 120-2 manualsIf so I would love to get thoseEmail[email protected]Also could you tell me where the injector pump relay is locatedThank youJoe

Joe decker said:Did you ever get the 120-2 manualsIf so I would love to get thoseEmail[email protected]Also could you tell me where the injector pump relay is locatedThank youJoeClick to expand...JoeI just sent you email with what I have on it .

Thanks againJoe

Can you please email me a copy of the service manual for the EX120-2thanks[email protected]

Hello everyone, I’m new to this forum, i would like to request for a copy of ex120-3, i have similar problems with what is discussed here but inwould like to pinpoint the faulty electronic items.My email is[email protected]Thanks in advance

Hi all I just bought an EX120-2 everything runs slow, I'm going to start checking all the normal things mentioned but would like to get all the service manuals if someone can please send them to me that would be great. ThankYou in advance. email to[email protected]

Hey guys I have a ex-120-2 had problems with the electronics so we bought a conversion kit for it and have it installed but the hydraulics are very slow. Does anyone have a detailed installation manual for this? We have instructions but they are a bit vague. A very good heavy machinery mechanic is doing all the work but is having trouble finding anyone who has done these before and no one wants to help us out. He has went through all the pumps and everything but just can't quite figure out why the hydraulics are moving so slow. All the pressures are good on the main pump and pilot pump all new o-rings springs were cleaned and the list goes on. Any help would be much appreciated

I did the same conversion directions suck and no help. So I printed out all the pictures I could find showing hose routing and pump adapter. Ok got that, then could not find where hose went on valve block. I compared pictures of all the different kits for sale and found one part I didn't have and couldn't buy separately. It is an adaptor to replace DP sensor which is where hose goes. I took an old DP sensor I had took It apart, drilled It out brazed in a hose fitting sealed up the holes on the sides re installed Orings and it worked.All functions work fast enough, Your not going to get the speed of a new machine but its workable.Send me your email and ill send pics of what I followed. I don't know how to post pics.Kevin

capnkev said:I did the same conversion directions suck and no help. So I printed out all the pictures I could find showing hose routing and pump adapter. Ok got that, then could not find where hose went on valve block. I compared pictures of all the different kits for sale and found one part I didn't have and couldn't buy separately. It is an adaptor to replace DP sensor which is where hose goes. I took an old DP sensor I had took It apart, drilled It out brazed in a hose fitting sealed up the holes on the sides re installed Orings and it worked.All functions work fast enough, Your not going to get the speed of a new machine but its workable.Send me your email and ill send pics of what I followed. I don't know how to post pics.KevinClick to expand...Hey Kevin,Please send your pictures to[email protected]Thanks!

blange8301 said:Hey guys I have a ex-120-2 had problems with the electronics so we bought a conversion kit for it and have it installed but the hydraulics are very slow. Does anyone have a detailed installation manual for this? We have instructions but they are a bit vague. A very good heavy machinery mechanic is doing all the work but is having trouble finding anyone who has done these before and no one wants to help us out. He has went through all the pumps and everything but just can't quite figure out why the hydraulics are moving so slow. All the pressures are good on the main pump and pilot pump all new o-rings springs were cleaned and the list goes on. Any help would be much appreciatedClick to expand...Can you email me the those kit instructions to[email protected].thanks

I'm new on here, have an ex120-2 hydraulics low and engine only speeds to high idle. put in P and it stalls the engine. Any help would be great, also looking for manuals if anyone can share. Thanks

Welcome to HEF MK! Check your controller fuses first, especially the 1 amp. Also in the future start a new post rather than piggybacking off an existing post. If you use the search feature in the upper right below your username and search Hitachi you will find lots of posts with your same complaint that will probably help you out.

Tool_King do you still have a service manual you could share for the 120-2 my email is[email protected]thanksMike

capnkev said:I did the same conversion directions suck and no help. So I printed out all the pictures I could find showing hose routing and pump adapter. Ok got that, then could not find where hose went on valve block. I compared pictures of all the different kits for sale and found one part I didn't have and couldn't buy separately. It is an adaptor to replace DP sensor which is where hose goes. I took an old DP sensor I had took It apart, drilled It out brazed in a hose fitting sealed up the holes on the sides re installed Orings and it worked.All functions work fast enough, Your not going to get the speed of a new machine but its workable.Send me your email and ill send pics of what I followed. I don't know how to post pics.KevinClick to expand...Hi Kevin I to installed the kit with Chinese instruction , can i also get the info from you , thanks Shane[email protected]

capnkev said:I did the same conversion directions suck and no help. So I printed out all the pictures I could find showing hose routing and pump adapter. Ok got that, then could not find where hose went on valve block. I compared pictures of all the different kits for sale and found one part I didn't have and couldn't buy separately. It is an adaptor to replace DP sensor which is where hose goes. I took an old DP sensor I had took It apart, drilled It out brazed in a hose fitting sealed up the holes on the sides re installed Orings and it worked.All functions work fast enough, Your not going to get the speed of a new machine but its workable.Send me your email and ill send pics of what I followed. I don't know how to post pics.KevinClick to expand...Going through the same nightmare myself right now. Any chance you could share what you followed for installing the kit? I got the instructions from SINOCMP, but they are garbage. My email is[email protected]. Thank you so much. I'm at a point that I don't know where to connect the hose to the control valve. Thank you so much - Jason

hi I hace similar problem with my EX120-3 excavator. Could anyone email me service manual for this equipment and also the installation instruction for the conversion kit. Thanks.

by the way my email add[email protected]

Wow..lots of new ex120 owners on here..have owned my Hitachi for several years now...most of you know this and it probably is already mentioned in this thread...if you have weak hydraulics and stalling always first check the screen filter in the fuel line banjo fitting..lots of crud in the fuel tank if original on these old ex120s...I also find that keeping the tank over half full slows the clogging of screen..good luck guys

capnkev said:I did the same conversion directions suck and no help. So I printed out all the pictures I could find showing hose routing and pump adapter. Ok got that, then could not find where hose went on valve block. I compared pictures of all the different kits for sale and found one part I didn't have and couldn't buy separately. It is an adaptor to replace DP sensor which is where hose goes. I took an old DP sensor I had took It apart, drilled It out brazed in a hose fitting sealed up the holes on the sides re installed Orings and it worked.All functions work fast enough, Your not going to get the speed of a new machine but its workable.Send me your email and ill send pics of what I followed. I don't know how to post pics.KevinClick to expand...Thnk a lot jakex120 my unit not stalling but tends to be slow and hot hydraulics after 1 hr operation. My unit is already fittes with conversion kit. If anyone could provide instruction guide on the conversion kit just to check if the hydraulic hishi capnkev!! read your post. may i request for the pictures on hw you went about the conversion kit. I just need to check installation on my unit thnks

capnkev said:I did the same conversion directions suck and no help. So I printed out all the pictures I could find showing hose routing and pump adapter. Ok got that, then could not find where hose went on valve block. I compared pictures of all the different kits for sale and found one part I didn't have and couldn't buy separately. It is an adaptor to replace DP sensor which is where hose goes. I took an old DP sensor I had took It apart, drilled It out brazed in a hose fitting sealed up the holes on the sides re installed Orings and it worked.All functions work fast enough, Your not going to get the speed of a new machine but its workable.Send me your email and ill send pics of what I followed. I don't know how to post pics.KevinClick to expand...

Good day capnkev!! read your post. Having the same problem connecting hoses from the conversion kit. Can you provide the pictures you worked out for theconversion kit? Thnk you mch it will helped a lot. My email[email protected]

capnkev said:I did the same conversion directions suck and no help. So I printed out all the pictures I could find showing hose routing and pump adapter. Ok got that, then could not find where hose went on valve block. I compared pictures of all the different kits for sale and found one part I didn't have and couldn't buy separately. It is an adaptor to replace DP sensor which is where hose goes. I took an old DP sensor I had took It apart, drilled It out brazed in a hose fitting sealed up the holes on the sides re installed Orings and it worked.All functions work fast enough, Your not going to get the speed of a new machine but its workable.Send me your email and ill send pics of what I followed. I don't know how to post pics.KevinClick to expand...Could you please send me the directions and pictures you followed. I’m having the same problem right now. My emailIs[email protected]. Thank you!

daddieboy said:Hey Weewards if you are ssking for the installation manual it supposed to come with, yes i do have. Here is my address[email protected]Click to expand...Hey daddieboy if you still have the installation instructions for the manual kit could you please email them to me at[email protected]. I am dealing with the same problems right now and would appreciate it!

hi all, does anyone have a electrical schematic for the Hitachi EX120 or a technical manual. can you email me[email protected]. Tracing back some wires on an old unit and got a few problems so harness rebuild in a while!! I'll get less of a headache with the schematics. Thanks in advance.

https://kattrak.com/spares/others/hitachi-spare-parts/found some parts manuals online

There are threads here on HEF that contain links to a tech manual for an ex200- 2.... Or 3... Can't remember most of the content is completely applicable to the 120's with the exception of the obvious things... I don't remember which threads but there are a few... It's a several megabyte file on one of the file sharing sites.... Unless someone else can post it or the links up....

Thanks Ronsil, i saw an EX200 manual but the pump look different and so does the control wiring. I'll keep looking for the -2 and -3

ex120-3 manualLACHAU said:Agree with your opinions.Regarding to Technical Manual, I never have used the J.Deere manual so I have no idea!! but I have a feeling that HITACHI's documentation is easy to understand also. I attached file for your reference.https://www.mediafire.com/file/o8dxek1yvr4h5tm/EX120-3_T135E-00_Technical_Manual.pdf/fileView attachment 215872Click to expand...

I have a customer with the Hitachi 120-3 the hydraulic system condition is excessive loading the motor on all functions it will barely move around the owner had it in a pit when problem started, he was able to get it up on the outside of pit. I'm going today to do a basic check on fuses and visual inspection of wiring harness. Does anyone have a service manual PDF file to share also if I find the electronics bad I will suggest the pump conversion. I would like the installation directions if anyone have them... I'm looking at a and for a good place to start diagnostics my e mail is[email protected]thanks in advanced

Lex Carter said:I have a customer with the Hitachi 120-3 the hydraulic system condition is excessive loading the motor on all functions it will barely move around the owner had it in a pit when problem started, he was able to get it up on the outside of pit. I'm going today to do a basic check on fuses and visual inspection of wiring harness. Does anyone have a service manual PDF file to share also if I find the electronics bad I will suggest the pump conversion. I would like the installation directions if anyone have them... I'm looking at a and for a good place to start diagnostics my e mail is[email protected]thanks in advancedClick to expand...I tried sending the tech manual but your email is kick back

Hi Can you send me a manual for an EX120-3 please i have some mechanical and hydraulic issues that i need to sort out. Thank and much appreciated.[email protected]

capnkev said:I did the same conversion directions suck and no help. So I printed out all the pictures I could find showing hose routing and pump adapter. Ok got that, then could not find where hose went on valve block. I compared pictures of all the different kits for sale and found one part I didn't have and couldn't buy separately. It is an adaptor to replace DP sensor which is where hose goes. I took an old DP sensor I had took It apart, drilled It out brazed in a hose fitting sealed up the holes on the sides re installed Orings and it worked.All functions work fast enough, Your not going to get the speed of a new machine but its workable.Send me your email and ill send pics of what I followed. I don't know how to post pics.KevinClick to expand...my email:[email protected]

arshad87have you gone through conversion? instructions included in the kit is vague. pls advice if you need assistance. you can email me at[email protected]

Hi members sorry but I don't have a manual. A friend of mine has a Hitachi Ex120 - 2 that has been sitting not started for sometime the engine turns over but no smoke, fuel system is primed the owners said it always started and ran very good. I have not checked it out or seen the unit yet.Just a little note I'm a old school retired Red Seal Heavy Duty Mechanic since 1968. I'm thinking this an electrical problem not mechanical any in put would help. Thank you all.Best RegardsFred Thompson

Hi members Fred here a friend has a EX 120-2 been parked sometime it has always ran well and started after parked this time engine cranks but no smoke and no start. Owners says the filters and pump are primed.I have not seen the machine yet, any ideas. Pretty sure it's electrical. Thank you.Best RegardsFred Thompson [Theoldbear]Red Seal Heavy Duty Mechanic since 1968[email protected]

Pretty sure that no smoke equals no fuel getting to the engine. Check the water separator, they had a tendency to leak, this would cause loss of prime. You could try priming it as well. Also, I belive one or two of the banjo bolts on the fuel line may have a screen in them that can get plugged up ....start with the easy stuff first

Good morn, new member but been lurking around. Pulled the trigger on an EX120-2. Has a minor issue. Can I post here or start a new thread?

Welcome to HEF JDCrow!Please start a new thread.

mg2361 said:Welcome to HEF JDCrow!Please start a new thread.Click to expand...Thanks!

Hi everyoneHitachi 120-3 stallingCheck that the accelerator cable that goes the injector pump is in good condition, because it runs under the exhaust it can melt , the inner cable has a find plastic coat that when melted can catch or jam it from working right if in doubt start the digger and put it by hand and tie it some way and then work the digger hope this makes sense

Also stops it revving up

HUGO4it said:Hi everyoneHitachi 120-3 stallingCheck that the accelerator cable that goes the injector pump is in good condition, because it runs under the exhaust it can melt , the inner cable has a find plastic coat that when melted can catch or jam it from working right if in doubt start the digger and put it by hand and tie it some way and then work the digger hope this makes senseClick to expand...On my list

There are a lot of people on this thread who have inserted or were in the process of inserting a hydraulic conversion kit in their ex120-2 or ex200-2. I would like to know how people have found the results and if there are in cons to doing itYour feedback would be greatly appreciated as I am looking at converting my ex120-2Thanks Marcus

02DIG said:There are a lot of people on this thread who have inserted or were in the process of inserting a hydraulic conversion kit in their ex120-2 or ex200-2. I would like to know how people have found the results and if there are in cons to doing itYour feedback would be greatly appreciated as I am looking at converting my ex120-2Thanks MarcusClick to expand...Hi, I did mine 3 years ago , its slower but no more ecm fuses blowing, i say i am happy with it

bc timber said:Hi, I did mine 3 years ago , its slower but no more ecm fuses blowing, i say i am happy with itClick to expand...Hi Bc TimberThanks for replying to my question. How do you find tracking? Can you still use the hare mode and is your pvc still plugged in? And did you convert to a manual throttleThanks

yep still plunged in , the hare mode works just fine.

bc timber said:Hi, I did mine 3 years ago , its slower but no more ecm fuses blowing, i say i am happy with itClick to expand...what is the procedure for this conversion

chHart said:Thnk a lot jakex120 my unit not stalling but tends to be slow and hot hydraulics after 1 hr operation. My unit is already fittes with conversion kit. If anyone could provide instruction guide on the conversion kit just to check if the hydraulic hishi capnkev!! read your post. may i request for the pictures on hw you went about the conversion kit. I just need to check installation on my unit thnksClick to expand...

chHart said:Thnk a lot jakex120 my unit not stalling but tends to be slow and hot hydraulics after 1 hr operation. My unit is already fittes with conversion kit. If anyone could provide instruction guide on the conversion kit just to check if the hydraulic hishi capnkev!! read your post. may i request for the pictures on hw you went about the conversion kit. I just need to check installation on my unit thnksClick to expand...Hi there I have a Hitachi ex120-3 with same problem just wondering why do hydraulic oil heat up after 1 to 2 hours working did you ever get it sorted in your machine any help would appreciated thanks

I'm new to this forum. I have a ex120-2 one day it wouldn't throttle up ec motor made a grinding noise. I could pull lever over and would hold rpm, if you pushed any of the speed buttons it drop in rpm. Was no blown fuses check continuity of wires between ec motor and ec computer all good. Both computers reds lights blink, looked over all wiring. Put new ec motor and ec sensor on no difference. Unhooked throttle cable can pull by hand , spring returns cable to off position. Help Please Thank you

Welcome to HEF wifeshelper!Should have started your own thread. Anyway, cable good? Did you check the voltage on the EC position sensor at low idle to make sure it is at 2.5 - 2.6 volts? (do not unplug/plug in the EC motor with the key on, it WILL ruin your Pump and Valve Controller). Check the voltage by backprobing. Did you perform a relearn procedure? There are many posts in the forum about all these procedures.

02DIG said:There are a lot of people on this thread who have inserted or were in the process of inserting a hydraulic conversion kit in their ex120-2 or ex200-2. I would like to know how people have found the results and if there are in cons to doing itYour feedback would be greatly appreciated as I am looking at converting my ex120-2Thanks MarcusClick to expand...Conversion made mine so slow that it was not even worth trying to dig, took kit off and bought new hyd controller and much better now.

I'm looking for the hydraulic schematic for the Hitachi EX120-3 also.My email is[email protected].Thank you

Diesel0003 said:I'm looking for the hydraulic schematic for the Hitachi EX120-3 also.My email is[email protected].Thank youClick to expand...I emailed the manuals to you .Let me know you have them downloaded and saved.

Hi,,newbie here,,please help about my ex120-2,mfg no 12n-32841,,machine cannot working and travel and all wire was cut off

Mohd Azizi said:Hi,,newbie here,,please help about my ex120-2,mfg no 12n-32841,,machine cannot working and travel and all wire was cut offClick to expand...Sorru about your machine. You might want to start a new thread or go over 1 step at a time with pictures. Lots of great help here, might take some time to sort your issues.

originally this machine works well even though all the wires related to the working mode have been cut,,,and I have changed all the strainers and my plan is to make a pressure tester,,,may I know what the pressure reading is?

How do we know if the shut off valve has a problem?

tomex120 said:Did you and spunkeymonkey solve the hitachi ex120 hydrolic stall problem, I have the same problem only when the machine gets hot?TomClick to expand...Hello I have the problem also. It's works normal when ist cold

tarzan said:I am interested in Hitachi EX120-3 manuelClick to expand...Hello...do you have a service manual of ex120-3

-3Doc said:I have the workshop manual, technical manual and operators manual for this machine.Click to expand...Hello 3Doc do you have a service manual of ex120-3

-3Doc said:You need the manual to replace the sensor and set the voltage properly. You can put the machine into a limp mode in order to get it home. If you look on the bottom of bothe pumps there is a four bolt cap plate over the end of the swash cylinder pistons. If you remove that plate you will see that it has a peg sticking up from the underside of the plate, if you turn the plate 90 degrees and replace it back in the hole then the pin will put the pumps into about halve swash and they will stay there the you can get the machine home if you feather the controls. As for your problem it sounds to me like the pump displacement solenoids, they tend to work fine when cold but as the machine heats up the coils break down and they quit working then the machine goes to full swash and stalls. Good luck.Click to expand...Hello 3Doc do you have a service manual of ex120-3

tarzan said:[email protected]THANKS!Click to expand...Can you send me that also?

gilcaay79 and anton_baydakWhat are your emails so I can send you the books .

tool_king said:gilcaay79 and anton_baydakWhat are your emails so I can send you the books .Click to expand...[email protected]

anton_baydak said:[email protected]Click to expand...Is there an angle sensor on 120-5. Location?

anton_baydak said:[email protected]Click to expand...You wanted the 120-5 manuals ?

tool_king said:You wanted the 120-5 manuals ?Click to expand...Yea please

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