Onan fuel pump or carb
My Onan 4000 model KY L with 170 hours will start and run for a couple of minutes then it dies. Acts likes it is running out of gas. Knowing that the fuel tank was full I suspected the fuel pump. ...
Forum Discussion
Apollo11sailor wrote:
My Onan 4000 model KY L with 170 hours...
Is it possible that the pump has degraded and can no longer sufficiently pump fuel from the tank?
Spec L and 170 hours...How Old? Still Warranty? Have you been using it regularly or at least giving it a monthly exercise?
What Trouble Code is blinking on your Start/Stop switch or Control Panel?
If it's young with low hours, pump failure isn't likely. Still any part can fail prematurely. But... If the coach stands without genset use, especially without stabilized gas, carb trouble can develop within a couple months.
We had a gunked up carburetor. I could start it and it'd run under load till the load came off. Example, would carry air conditioner compressor (heavy load) till it cycled off, leaving only air conditioner fan (light load). Then it'd quit. The idle passages were clogged. Don't forget, the genset runs at a steady 3600-RPM, BUT! at light or no load, the small idle passages come into play even if it's still running 3600. Apply a load and it's still running 3600 but on larger passages that don't clog as easily.
The gas tank is full. OK, now can you check to make sure you don't have a loose clamp or pinhole leak spot?
