Loader JD 401A diesel loader looses rpm after about 3 hours runtime

zpq1045 · Feb 14, 2011

Hi All,
I have a JD 401A diesel loader that looses rpm after about 3 hours runtime. Outside temp doesn't seem to matter, 30 to 70f. Since the first time this happened I have replaced the fuel filter and fuel shutoff solenoid in the injector pump. Yes the solenoid was bad as a coincidence I guess.

Last time I didn't think that it would make it to it's parking space. Running about 1000 rpm at full throttel.

Any ideas?

Thanks.

Tx Jim · Feb 14, 2011

Check flow from tank as dirt/grass or other unknown foreign material has been known to get in fuel tank. Also disconnect fuel return line on inj pump leading to injectors & tank. Then check while running to see if fuel comes out of pump fitting. If no fuel comes out remove fitting and try running engine again. This fitting has be known to get plugged with inj governor ring material.

dex3361 · Feb 14, 2011

Is it blowing any smoke? It could be a air intake restriction, so check your air filter. Make sure you are not collapsing your air intake hose between your filter and manifold. This could also be something washing over the fuel tank outlet and blocking the fuel flow. Check and see if there is a screen that plugs off the exit of the tank.