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Deere 750c throwing code

Geno · 2021-07-24 17:12

I have a Deere 750C that just suddenly started having a problem.. I can be tracking or pushing and it suddenly stop moving .. then a code F640 shows up in the dash . Anyone know what’s going on here?

Replies7
  1. #1mg23612021-07-25 06:24

    Serial number? Does the engine rpm drop below 1900 rpm when it happens? If it does then you have an engine power issue. If it stays at 2000 rpms or higher when it happens, then there is an issue with the pump speed sensing circuit (sensor/speed ring/wiring/connectors).

  2. #2Geno2021-07-25 18:17

    PIN#847936....Rpm’s stay up in the 26 to 27 area

  3. #3Geno2021-07-25 18:21

    Just got it back from mechanic .. had a fuel injector malfunction so had six new ones installed, a valve cover leak repaired and while there had it serviced..engine oil change and final drive oil changed.... 100’ off the lowboy it stopped dead in its tracks..

  4. #4mg23612021-07-26 05:20

    Engine fast idle Spec is 2240-2275. So either the engine linkage is misadjusted or the pump speed sensing circuit has issues. You need to check the engine rpm with a external hand held tachometer and compare it to what the dash indicates.

  5. #5Geno2021-07-26 06:55

    Ok thanks! Yeah I noticed that rpms seemed high.. silly me thought maybe it was just running better since new injectors were installed..lol... that makes sense !

  6. #6Vetech632021-07-26 07:56

    WOW, this sounds familiar!

  7. #7Geno2021-07-26 18:23

    Today I adjusted throttle linkage ... didn’t do any good ..still randomly stops for no reason.... getting a 750k delivered in the morning..gotta get some work done! ... will either repair 750c later or who knows might trade it in on the 750K