Just to let you know it is possible to fix the Onan reasonably sometimes.
I wanted an onboard gen that can come on when we are away if it gets too hot for our animals and there is no power. (texas is brutal in the summer)..
I found a used 7kw unit, not working, for $200.. assuming that the rotor was broken..
doing some testing (thanks to smokstak.com forum), seems that the drive belt pulley (rubber between to metal parts) had finally fallen apart (this unit has 4,000 hours).
$45 including a new belt (why not?) and a few hours work and voila!.. perfectly good gen. still have to add trifuel and install it, but have tested powering the FW with no problems.