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Kx121-3 possible valve issue

Rivet · 2023-09-12 21:49

Good afternoon My KX121-3 has an hydraulic issue that has been on going. Auto idle works when controls are touched but nothing moves. I’ve taken the screen filter out of the control block cleaned reinstalled and was up and running. This worked for a day and now I’m back to nothing. New filters and oil. Any advice would be greatly appreciated.

Replies9
  1. #1uffex2023-09-13 04:39

    Good day If the screen filter is blocking suggests that the pump (K refer to the pump as pilot pump) is creating the material loosing pressure. Test the pressure as illustrated. Kind regards Uffex

  2. #2Rivet2023-11-01 05:32

    Good Morning Uffex I have tested the pilot pump pressure and have the 600psi where I should. I’ve taken the main discharge line off the pump and capped the ends. The manual says I should have 3000psi at the pump. While starting engine the pressure gauge was moving with each engine crank. Once started pressure was zero. PSI Does this confirm main pump or do I require flow for this test to work? Thanks in advance.

  3. #3uffex2023-11-01 06:00

    Good Day Servo pressureshould be maintained at low revolutions did you check the pressure with engine idle speed? Im not sure what the main pressure has to to do with the problem as I am understanding your post we are talking auto ide. Please correct me if I am wrong. Kind regards Uffex

  4. #4Rivet2023-11-01 06:49

    Good morningThe Auto Idil works fine. Nothing is working or barely working. Trying to figure out if it’s my main pump or a valve issue. I have the correct pilot pressure but can’t get the main pump pressure Thanks

  5. #5uffex2023-11-01 09:18

    Good day Rivet When you checked the pilot/servo pump pressure, was that post filter or further down the line? Kind regards Uffex

  6. #6uffex2023-11-01 09:27

    Good day Rivet Please have a look at the attached, it is not uncommon for this one to give that type of problem. Kind regards Uffex

  7. #7Rivet2023-11-01 09:28

    Good Morning Uffex Before and after the pilot filter. Thanks

  8. #8Rivet2023-11-01 09:32

    I will check when I get home. I can’t open on my phone. The track levers unlock when safety lever arm is down but nothing moves. Thanks

  9. #9uffex2023-11-01 10:53

    Good day Rivet The crawler - track controls are mechanically operated (rod & Cable) have no effect with Control lock out. These should work if the pilot lock out fails. Kind regards Uffex