Intermittent Onan Generator

[George Schweikle]

I have an Onan Microquiet 4000 generator that is giving me fits. Sometimes, it won't accept an A/C or Microwave load and sometimes it will. When it acts up, it surges, backfires, and the automatic transfer switch cuts off the 110V power from the genarator. I have replaced the fuel line to the gas tank, the choke was adjusted and engine "de-carboned" at the dealer today, and the thing ran fine. Upon returning home and letting things cool off, the old problem surfaced after 15 minutes running. Earlier, I paid for one of the "on line experts", and the response was to adjust the valves and clean the carburator.

I'm returning to the dealer early tomorrow morning. The issue sounds like it may be heat or time related, which may result in just starting to change parts like the circuit board, etc. The generator is on a 1999 Safari TREK,and has 375 hours. Has anyone else ever experienced these symptoms?

[ga traveler]

these generators give a lot of problems with the carbs. They are small and cheap. (not in price) You might try to clean the carb.

[George Schweikle]

Update:
Day two, back at the dealer. A different tech looked at the roof air installation and said it wasn't sealed correctly which could lead to "short cycling" where the unit ingests some already cooled air, the thermostat thinks it has cooled sufficiently and turns off the compressor, then it tries to turn on right away against "high head pressure". This overloads the generator and it bucks, snorts and/or turns off. The offending A/C air leak was sealed, then the voltage was seen to be fluctuating too much. In order to expedite repair, I drove to Louisville and picked up a new voltage regulator from a Cummins/Onan facility (very pricey, but I needed to get ready for a trip with lots of dry camping and generator use). Voltage, Hertz, and mixture checked, and adjusted, and as of now, everything seems to run correctly.

Quote:

Originally Posted by George Schweikle I have an Onan Microquiet 4000 generator that is giving me fits. Sometimes, it won't accept an A/C or Microwave load and sometimes it will. When it acts up, it surges, backfires, and the automatic transfer switch cuts off the 110V power from the genarator. I have replaced the fuel line to the gas tank, the choke was adjusted and engine "de-carboned" at the dealer today, and the thing ran fine. Upon returning home and letting things cool off, the old problem surfaced after 15 minutes running. Earlier, I paid for one of the "on line experts", and the response was to adjust the valves and clean the carburator. I'm returning to the dealer early tomorrow morning. The issue sounds like it may be heat or time related, which may result in just starting to change parts like the circuit board, etc. The generator is on a 1999 Safari TREK,and has 375 hours. Has anyone else ever experienced these symptoms?