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Hitachi Ex120 Problem

Discussion in 'Excavators' started by spunkeymonkey, Jul 7, 2009.

  1. tool_king

    tool_king Senior Member

    Joined:
    Mar 29, 2010
    Messages:
    1,684
    Occupation:
    road mechanic owner
    Location:
    new jersey
    3Doc
    Would you mind sharing the workshop manual, technical manual and operators manual for the ex 120 -2
    machine. My email address is tool_king@hotmail.com .Please let me know if you have any other manuals to share .I have a lot of manuals to share too.
    THANKS
    ED
     
  2. -3Doc

    -3Doc Well-Known Member

    Joined:
    Jul 29, 2009
    Messages:
    119
    Occupation:
    Ticketed HD Mechanic
    Location:
    British Columbia
    Been very busy fixing broken machines!!
     
  3. -3Doc

    -3Doc Well-Known Member

    Joined:
    Jul 29, 2009
    Messages:
    119
    Occupation:
    Ticketed HD Mechanic
    Location:
    British Columbia
    Send me a pm we will talk!!
     
  4. nolap

    nolap New Member

    Joined:
    Nov 17, 2011
    Messages:
    2
    Location:
    ireland
    I would be very interested in these manuals also.My email address is nolap1@hotmail.com.
    Thanks nolap
     
  5. thaunho

    thaunho New Member

    Joined:
    Nov 22, 2011
    Messages:
    1
    Location:
    Myanmar
    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.
     
  6. BrianGrenier

    BrianGrenier Well-Known Member

    Joined:
    Jun 28, 2010
    Messages:
    208
    Location:
    Willow, AK
    My

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

    seadara Member

    Joined:
    Jan 28, 2012
    Messages:
    7
    Location:
    INDIA
    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:seadara@hotmail.com. Thanks,
     
  8. digfaster

    digfaster Member

    Joined:
    Aug 23, 2011
    Messages:
    20
    Occupation:
    power plant operator / farmer
    Location:
    indiana
    Check the variable pressure compensator valve on the pilot system
     
  9. seadara

    seadara Member

    Joined:
    Jan 28, 2012
    Messages:
    7
    Location:
    INDIA
    HITACHI EX120-3 circuit diagram

    Hello 3Doc, could you please email me of HITACHI EX120-3 CIRCUIT DIAGRAM?Please.
     
  10. asripaka

    asripaka New Member

    Joined:
    Nov 10, 2011
    Messages:
    2
    Location:
    malaysia
    hitachi ex120-2 pump angle sensor checking and proper setting

    need advice on how to check pump angle sensor and proper adjustment of that sensor. Anybody have the procedure please help me...........
     
  11. apw35

    apw35 New Member

    Joined:
    Feb 3, 2012
    Messages:
    1
    Location:
    Norther Ireland
    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?
     
  12. danc

    danc Well-Known Member

    Joined:
    Mar 11, 2009
    Messages:
    89
    Location:
    ireland
    hello and welcome
    here's a final drive from an ex120-1
    you need to remove the casing next (top of picture)

    if you look close inside you can see the 'step ' to the inner teeth

    crack the seal of the gasket before fully removing the last bolt, watch your feet:)
     

    Attached Files:

  13. Melson

    Melson Member

    Joined:
    Feb 4, 2012
    Messages:
    5
    Location:
    Tennessee
    Please send 120-2 manuals to melson_michael@yahoo.com

    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!
     
  14. wildhorse trnr

    wildhorse trnr Well-Known Member

    Joined:
    Feb 13, 2010
    Messages:
    78
    Occupation:
    Field Technician
    Location:
    Texas
    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.
     
  15. Melson

    Melson Member

    Joined:
    Feb 4, 2012
    Messages:
    5
    Location:
    Tennessee
    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!
     
  16. Melson

    Melson Member

    Joined:
    Feb 4, 2012
    Messages:
    5
    Location:
    Tennessee
    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.
     
  17. seadara

    seadara Member

    Joined:
    Jan 28, 2012
    Messages:
    7
    Location:
    INDIA
    HITACHI EX120-3 Hydraulic sysyetm failure and heat

    Hello -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: seadara@hotmail.com. 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
     
    Last edited: Feb 16, 2012
  18. Richardatwinder

    Richardatwinder Member

    Joined:
    Feb 17, 2012
    Messages:
    9
    Location:
    England
    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.

    cheers

    Richard
     
  19. rgl726

    rgl726 Well-Known Member

    Joined:
    Sep 11, 2010
    Messages:
    175
    Location:
    cebu city, philippines
    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?
     
  20. Richardatwinder

    Richardatwinder Member

    Joined:
    Feb 17, 2012
    Messages:
    9
    Location:
    England
    ex100-2

    HI Thanks for the reply

    Yes 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