Forum Discussion

KnowNuthin's avatar
KnowNuthin
Explorer
Aug 25, 2015

Generator fuel pump

I have an Onan 4000 GenSet...

There is a white wire that supplies 12 V to the electric fuel pump… Right now I'm getting approximately 6 to 7 V out of that wire… Not enough to run the fuel pump… In another post I raise the question regarding my battery isolator and possibly corroded battery connections…

Can I just run a hot wire to the fuel pump installing a switch so I can shut it off or is that white wire automatically switched to turn the fuel pump on and off as needed as the float bowl fills and empties ?
  • KnowNuthin's avatar
    KnowNuthin
    Explorer
    Aug 26, 2015
    I putzed with the cables a bit last night... didn't have time to loosen/clean/tighten everything but I did wiggle all the connections I could get to and the genny gave some sign of life....


    I think we're on to something here....

    This weekend I'll replace the isolator (obviously rusted in places) and clean all the connections I can find... and keep my fingers crossed
  • ksg5000's avatar
    ksg5000
    Explorer
    Aug 25, 2015
    Check/Clean all the battery terminal as well as the grounds (both vehicle and generator) - that should eliminate some of the obvious low voltage issues. Then start the engine which should put chassis/coach batteries "online" and try and start the generator.
  • Ivylog's avatar
    Ivylog
    Explorer III
    Aug 25, 2015
    Most electric fuel pump shut off automatically when the pressure is high enough. As a temporary fix I would run the wire but you do need to find the real problem.
  • azrving's avatar
    azrving
    Explorer
    Aug 25, 2015
    I would find the problem. Doing that will only make it less safe.

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