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Hitachi 120-2 questions and anwsers

Discussion in 'Excavators' started by SoutheastSavage, Sep 27, 2020.

  1. SoutheastSavage

    SoutheastSavage Well-Known Member

    Joined:
    Sep 27, 2020
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    46
    Location:
    Kasaan Alaska
  2. maineplower

    maineplower Member

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    maine
    Do the gauges still work? Can you change the travel speed?
     
  3. SoutheastSavage

    SoutheastSavage Well-Known Member

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    Sep 27, 2020
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    Location:
    Kasaan Alaska
    Travel speed doesn’t change. Fuel gauge and temperature gauge work. No hr meter but that was a issue before. It seems like when pvc was plugged in travel speed would change. But I had to unplug it to get stick in to function properly
     
  4. SoutheastSavage

    SoutheastSavage Well-Known Member

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    Sep 27, 2020
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    46
    Location:
    Kasaan Alaska
    So after running my machine for 10 hrs or so some or most of of the fittings on the conversion are leaking. Will keep you guys posted on what I do to fix it. If any one has any insight feel free to chime in
     
  5. maineplower

    maineplower Member

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    Location:
    maine
    Are they just poor quality fittings? You still happy with the conversion?
     
  6. SoutheastSavage

    SoutheastSavage Well-Known Member

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    Sep 27, 2020
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    46
    Location:
    Kasaan Alaska
    I think that’s the jist of it. Cheap fitting cheap o rings. I broke one just tightening it. But absolutely I have been out ripping stumps and ripping rock. Machine runs great. And remember before conversion I couldn’t even hardly use machine without it bogging down.
     
  7. William Ferguson

    William Ferguson New Member

    Joined:
    Sep 7, 2020
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    4
    Location:
    Richmond kansas
    Mine is running better than ever but it's a 790e deere only thing is pilot pump seems to be a little high on pressure and all functions work but if I boom in and bring stick in it bogs engine this is with two shims pvc isn't unplugged but I did pull fuse . should I just unplug?
     
  8. SoutheastSavage

    SoutheastSavage Well-Known Member

    Joined:
    Sep 27, 2020
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    Location:
    Kasaan Alaska
    Not sure I unplugged mine and it fixed the issue with not being able to stick in and boom up at same time. But mine wasn’t bogging the machine it was just very slow or would almost stop. If the fuse is pulled it should be same as in plugging
     
  9. SoutheastSavage

    SoutheastSavage Well-Known Member

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    Sep 27, 2020
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    Location:
    Kasaan Alaska
    I have still been using my machine. I replaced all the fitting and hoses on the conversion and that fixed my leaking issue so off to work I go. I also equipped 120 with led lights all the way around. A stereo and a new belly pan. Happy digging my friends
     
    LACHAU and RPMex like this.
  10. SoutheastSavage

    SoutheastSavage Well-Known Member

    Joined:
    Sep 27, 2020
    Messages:
    46
    Location:
    Kasaan Alaska
  11. SoutheastSavage

    SoutheastSavage Well-Known Member

    Joined:
    Sep 27, 2020
    Messages:
    46
    Location:
    Kasaan Alaska
  12. SoutheastSavage

    SoutheastSavage Well-Known Member

    Joined:
    Sep 27, 2020
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    Location:
    Kasaan Alaska
    Alright everyone. Machine has been working great operating great
    Although the other day my thumb got stuck closed. I replaced thumb sylonoid as well as my handle with a sure grip handle. Now I go to open thumb and it won’t open. Hose at the sylonoid jumps but no pressure to the cylinder. If I go to close thumb it works. So thumb is struck closed. Thinking it may be main relief for thumb part of valve body. Anyone have any insight. I’m screwed right now I have a bunch of brush to haul and I need my thumb to work
     
  13. mg2361

    mg2361 Senior Member

    Joined:
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    Occupation:
    Equipment Mechanic/Technician
    Location:
    Pennsylvania
    Pilot control pressure getting to the auxiliary spool caps on the main control valve?
     
    anuradha likes this.
  14. JDCrow

    JDCrow Well-Known Member

    Joined:
    Sep 25, 2020
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    102
    Location:
    Redmond, Or
    Just purchased the conversion kit. On the same road as you now. My harness was shot, so new one to clean it up. But ended up with pretty much same symptoms as your machine. I might hit you up for instructions on the kit
     
  15. JDCrow

    JDCrow Well-Known Member

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    Location:
    Redmond, Or
    Get your thumb working?
     
  16. SoutheastSavage

    SoutheastSavage Well-Known Member

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    Location:
    Kasaan Alaska
    Yes I had a mechanic come out we checked the spool in the valve body then we’re gonna check the line to see if anything had gotten in it when the mechanic realized my open side hose was going to my return so when I changed my thumb sylonoid I mixed up 2 hoses. 600 bucks for him to tell me I messed up. Oh well I’m up and ripping again and making money. Yeah let me know if you need a hand you will wish you had done conversion sooner
     
  17. JDCrow

    JDCrow Well-Known Member

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    Sep 25, 2020
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    102
    Location:
    Redmond, Or
    Glad it’s working. Conversion is done. And took your advise and had new hoses made and fitting ready to roll. Blew through 3-4 o-rings on the crazy long fitting that goes into the valve body. Got it replaced and then one goes on the new block. But other than that fine. Still issues with boom up, so it tells me I have to do some cleaning/inspection of shuttle valves /spools
     
  18. SoutheastSavage

    SoutheastSavage Well-Known Member

    Joined:
    Sep 27, 2020
    Messages:
    46
    Location:
    Kasaan Alaska
    Did you disconnect your pvc? My machine was really slow when I tried to stick in and boom up at same time. I unplugged pvc and it seemed to fix my issue
     
  19. JDCrow

    JDCrow Well-Known Member

    Joined:
    Sep 25, 2020
    Messages:
    102
    Location:
    Redmond, Or
    I did disconnect the PVC. No change. Hammering a trench for my auto mechanic. It’s tedious to push down to go up, but getting it done. Several here have stated i probably have a sticking valve somewhere. So get this ditch done and will start pulling it apart.
     
    SoutheastSavage likes this.