Onan 4000 just shuts down on load No tripped breakers

[howardwheeler]

We have a Onan 4000 in a Class C Minnie Winnie that just stops when its under a pretty heavy load. It's still under its rated amps but just stops. No breakers trip. I don't find anything in the manual about the gen shutting down except for low oil. If the AC is going and we have another appliance going and turn on the microwave, it just stops. I'm talking a total of around 21 amp load. What safety device is there on the Onan that causes the generator itself to stop running. It never trips any breakers.

[Chris_Bryant]

Does it bog down and die, or just shut off?

[Big_Katuna]

They have a low oil sensor that can shut it down. These have been known to shut down intermittently. Cheap to replace.

They also shut down if the voltage is too high or low. If the carb is dirty and it cant make the HP to maintain voltage it will shut down.

I had one that would shut down while driving if I hit a bump or made a hard right turn. Turns out it had a loose carb nut.

Yours also has an electric fuel pump. They fail too.