ONAN 4KYFA26100K won't stay running

[Bobbo]

I have an ONAN KY-FA/26100K generator that won't stay running.

I exercise it every month, and this is the first time since 2007 that it won't stay running.

The fuel tank is full.

The oil level is about 1/8 inch below full and WELL above the add mark.

It starts just fine, and the Progressive Industries EMS-HW30C deems the power fine and powers the breaker box. I turn on the A/C or the space heaters, and leave it. When I go back about 20 or 30 minutes later, the generator is not running.

Any ideas where to look?

[Sam_Spade]

You need to stick around while it is running and see what is happening.

The A/C is not a good test load to use when the power might be fluctuating a lot.

If there is a fuel filter has it been changed lately ?

[DrewE]

Maybe check carefully for obstructed cooling airflow due to leaves, mouse nests, milkweed fluff, or whatever.

[newman_fulltime]

Turn all your breakers off then see if it continues to run after the 20 minutes then one by one turn the Breakers on till the problem comes back that circuit is your problem