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Case 750K Engine Over Speed

leojmartin · 2020-11-17 10:18

My 750k was recently repaired after having a bad connection in the CAN wiring. After that repair everything was working fine for about 8 hours of work. Then when load was added the engine governor would quickly over react to the load change. Sometimes the rpm would get to 2800 rpm before I could push the throttle to idle. Once the load was reduced the engine would slow to 2100 rpm but was hunting 100-200 rpm. I checked the linkage high speed stop and found it to be set to a maximum of 2100-2200 rpm. I tested several times while traveling with no overspending. Once I try to put the blade in the dirt the over speed occurs again. Can this be related to the resent repair of the CAN wiring or do I have a new problem with the injection pump?

Replies3
  1. #1leojmartin2020-11-21 11:39

    @GaryHoff Any ideas? Thanks.

  2. #2GaryHoff2020-11-25 22:45

    Sounds like a injection pump issue, not a CAN issue. Is your engine oil overfull? The lift pump sometimes leaks diesel into the engine oil, and can cause overspeed. Has anyone tilted the cab recently? I have seen when someone forgets the throttle cable, and damages the injection pump.

  3. #3leojmartin2020-11-27 07:28

    I tilted the cab when I was searching wiring issues but I did disconnect the throttle linkage. I think I’m going to change the oil before deciding to pull the injector pump. Thanks.