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Hydraulic Pump coupler R&R komatsu PC40-7

Green40 ยท 2023-03-16 00:41

Am looking for repair manual/ info regarding hydraulic coupler replacement. Installed new starter recently and noted buildup of powdery rubber on old stater housing internal to flywheel. Material looked similar to the pile of rubber under my washing machine when the coupler failed. With 6500 hrs on the unit I am expecting it needs to be replaced. Anyone done this job? I have tools and resources. Need details on replacement of coupler.

Replies7
  1. #1LACHAU2023-03-17 11:52
  2. #2Green402023-03-17 12:55

    Thank you for the schematic. I do have the factory parts manual showing the same info. Am looking for process steps to remove and replace. Not sure what to remove or correct steps. Am in need of a repair manual with some detailed step by step info. It's a bit busy as you can see and I'd rather not mess something up by guessing how it comes apart.

  3. #3LACHAU2023-03-18 08:28

    here you are, good luck.

  4. #4Green402023-03-19 11:23

    Thank you for the information LACHAU. I have the machine in my shop and am beginning the removal process. Going to remove pump only not entire pump/engine as noted in the provided attachment. Info does help. Will upload pictures once I have the coupler out. I am betting it's pretty worn. Replacement OEM parts have been ordered.

  5. #5Green402023-03-22 16:16

    Well here is what I found. Glad I am changing it out. As you can see the rubber portion of the coupler has separated. Is this a oem coupler? Am replacing with oem. Also found this in my intake. I have always had a airfilter in place. Wondering if this had been there since I have owned it. Still ran good despite the organic blockage.

  6. #6Green402023-03-22 18:01
  7. #7pnwdirtmachine2026-06-09 11:45

    This post helped me with my issues. Thanks for the diagrams