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2017 Caterpillar 420f2it

Jhernandez940 · 2023-12-29 17:50

I have a 420f2it with a quick connect pin problem. When I hit the lock button the bucket tilts forward, the pins don’t engage. Also the loader valve/right joystick doesn’t tilt forward

Replies7
  1. #1ahart2023-12-30 11:32

    Start with a serial number so we can access the correct information, electrical/hydraulic schematics.

  2. #2Jhernandez9402023-12-30 11:39

    CAT0420FCHWD01810 sir thank you

  3. #3ahart2023-12-31 12:39

    I think if it were me, I’d be looking at the compensator spool valve in the auxiliary valve and checking it for sticking. There is a magazine about replacing for a separate issue. In first picture which is a drawing of the aux valve, the center control valve marked “1” is the compensator spool. Second picture is hydraulic schematic showing how the two circuits are linked together. Keep in mind, this is only a theory as I have not personally experienced the issue you’re having with the machine you have.

  4. #4Jhernandez9402023-12-31 13:15

    Thank you very much I’ll look into. I appreciate your help very much. I’ll post what I find as I go

  5. #5Jhernandez9402024-01-03 19:30

    After getting my own copy of the manual I noticed the aux valve hoses and tilt valve hoses were crossed. Everything works on the joystick now. Even the thumb roller. Do you know what exactly the thumb roller does?? Does it control the same aux valve to the quick connect pins? The unlock/lock button doesn’t seem to be working anymore. When I pressed the unlock/lock button before it sent a signal to the solenoids and you use to hear the valves actuate. Now nothing

  6. #6ahart2024-01-03 19:57

    The thumb wheel controls the aux valve for tool control. I’m not sure how swapping hoses caused the quick coupler solenoids to not function, what’s the story with this machine? New to you?

  7. #7Jhernandez9402024-01-03 20:23

    I picked it up at an oilfield auction. The backhoe part of the unit works fine, just been having problems with the loader. Does the switch use the same aux valves as the thumb roller or different set? I’m not sure how swapping hoses messed anything up