Allis Chalmers 5040 Injection Pump

Discussion in 'Repair & Technical Discussion' started by DragonflyGrit, Jul 24, 2017.

  1. DragonflyGrit

    DragonflyGrit New Member

    Jul 24, 2017
    I have an Allis Chalmers 5040(diesel) that keeps shutting off after 30 minutes of running. If it were the injector pump wouldn't it just quit running altogether and not crank up at all? To date, I have replaced the fuel pump, filters, and hoses.
    Thank you for any help and or suggestions.
  2. BigT

    BigT Member

    Sep 15, 2014
    Howdy DragonflyGrit, welcome to the tractor forum.

    Please wait for the pumpguy to show up. He is an expert on injection pumps and systems. In the meantime, below is my two cents FWIW.

    IMO, your problem is not with the injection pump. You have an obstruction somewhere in your fuel system. It may be as simple as a plugged vent in the fuel tank cap. Loosen the cap and see if it runs OK.

    It may also be a plugged fuel return line from the injectors back to the fuel tank.

    Blow the lines out with air. Remove the fuel tank cap before blowing into the tank to avoid rupturing the tank. Do not blow into the injection pump.
    Last edited: Jul 24, 2017

  3. DragonflyGrit

    DragonflyGrit New Member

    Jul 24, 2017
    Thank you BigT for the warm welcome and I will try your suggestions. It will probably be tomorrow before I get the chance but will let you know how it goes.
  4. thepumpguysc

    thepumpguysc Active Member

    Jan 25, 2015
    YUP.. floaters in the tank or clogged vent in the cap.. BIG T was paying attention in class.. Good call BT & thanks for the plug..
    The old 5040's didn't have "safety switches" like we have NOW..
    IT MIGHT have a filter screen in the shut-off valve at the bottom of the tank, I honestly don't know.. an air hoes & a couple of wrenches should get ya going..
  5. DragonflyGrit

    DragonflyGrit New Member

    Jul 24, 2017
    Thank y'all very much for trying. My father passed away and we are moving all at the same time so I will have to put this on the back burner for a while. I appreciate y'alls help and will let you know what happens when I can start working on it again.