Well maybe you need to contact Onan and have them revise their owner's manual were they state that operating the generator, every month, under load is required as part of the maintenance protocol. Running the generator has more to do than just flushing out stagnant fuel. Their is also something that has to do with residual magnetism. I am not quite sure how it works, but to avoid having problems with a generator that starts but does not produce sufficient voltage, you need to run a generator under load on a routine basis.
Fred
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