ONAN runs, stops, starts again
I was exercising my ONAN 4000 the other day as I do monthly and after about 45 minutes it just shut down. It re-started after a couple of minutes, again after 30-45 minutes before shutting down again....
Forum Discussion
since unit will start and run for a period...would indicate that you don't have a "hard" failure... There is not a low oil level switch on this unit. Agree with OP...most likely a fuel delivery problem, and if you pull fault code it will probably be a "36". The fuel pump is likely getting hot and stops delivering fuel, but also have seen control board circuit that powers fuel pump quit working when board gets hot, and this will require a board replacement. Diagnosis requires connecting a voltmeter or test lamp to the fuel pump circuit, then running to duplicate problem, then see if voltage to fuel pump goes away (bad board), or fuel pump just quits supplying pressure. If you pull fault code and is not a "36", then other tests need to be done, depending on code. Probably see this 100+ times a year at our generator shop.
