2004 Winnebago Onan Marquis Gold 5500.
Serviced generator replaced air/fuel/oil filters, both spark plugs,changed oil. Ran fine after fuel lines filled after replacing fuel filter.
Tried one more time later same day, get a solenoid chattering on generator. Chattering occurs with remote start in coach or start switch on generator.
Coach/engine batteries fully charged. Have 13.69 volts at the generator power in (meter at generator ground strap/12v power in) connector.
Generator starts normally with a jump box to generator ground strap and 12v power in at generator.
Sounds like a poor ground any idea where to check?
I have checked the ground bus behind the batteries (disconnected all cables wire brushed and applied dielectric grease and reconnected still have same issue).