RV Repair: onan carburetor, float bowl, starter switch

Question
QUESTION: Hello, I have been reading your posts to other people and must say you sound very knowledgeable with small engines.  Perhaps you could help me.  I have an Onan 4000 that is having carb issues...I am pretty certain that the carb sat too long (about a year) and the carb varnished up.  Anyway today I pulled the carb out in an attempt to rebuild or clean it...but there really is not much to it...the only thing that really comes apart is the float bowl but there is no needle and seat visible from anywhere.  Could you please give me a little advice on cleaning or rebuilding it?

ANSWER: Dean, In almost all of the onan's out these days there is really no way to rebuild the carb. The best thing I can tell you is to have left it on the generator and used some onan carb cleaner to it while it was running. I am afraid I don't know what to tell you to do know. You can try putting it back together and doing what I said and if that doesn't work you will need to order another carb from onan. Were you even able to get a carb kit for that carb? If you did then soaking it in some cleaner might also help. Remember never soak any part that has rubber. Thanks, Bill

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QUESTION: Thanks for responding Bill.  I cleaned what I could and put it back on...It will start and run for a while as long as I hold the starter switch on and hold the choke open...as soon as i let off either it dies out..it seems to be running okay when it is, but does it sound like a carb issue or maybe something electical?

Answer
Dean, It does sound to me like a fuel issue whether it is the carb or the fuel pump. When they sit for a long period the fuel turns into varnish and makes things gummy. That will make it run the way you describe to me. Make sure you have ample fuel pressure going to the carb and if so then I would look into replacing the carb. Thanks, Bill