Gunk in Onan Marquis 7000 carb

New Blue, as far as "rebuilding" the carb, what did you do? When I replaced the carb on our Onan Marquis 7000 there was no bebuild kit. And after taking the old one off I really didn't see anything to do other than an o-ring or two. The carbs on these things in my opinion are pure junk. Went to the Onan shop in Idaho Falls, ID. to get the new carb and when I asked the parts guy if he happened to have that particular carb number in stock his answer was "I better have 3 or 4 of them on the shelf because we go thru them". Sure enough he did. But now the soon to be boat anchor will start 3 out of about 8 times (cold start) as it should. The other times it chokes, pukes, loads up, back fires thru the carb twice after several push on the start button. Usually when a load turns on like the AC, etc. it will fart once or twice then pick up. No smooth transition. While we sit in Yuma for five months it gets started every month and a load put on it for about 30 minutes. I've used regular Sta-bil, Marine Sta-Bil, and Seafoam. Every time I see a Honda or Yamaha genny start I just cringe.