I have a B48G onan that hunts at low rpm. I noticed the idle & intermediate fuel passage has no welch plug. I don't see one on the John Deere parts list. Would this have anything to do with the hunting at low rpm?
Hunting at low speeds can be caused by many things. Fuel or ignition are the places to start. I would start with fuel, open the idle needle slightly. Add some Seafoamto your fuel, I have found that 50% of the time it will clean the internal passageways and jets, so you don't have to rebuild the carb. Check your point gap, I would set the gap at .018. I have included a website where you can download a service manual that may be of some help. Onans can be very fussy about idle RPM's, make sure that your's is set according to the specs. Post back with what you have done and the results for more help.
