I purchased an Onan 4000 that turned out had a stopped up carburetor. I tried to get a rebuild kit, not available. The only option was a new carb at over $500. I contacted the company below and ordered the kit for that generator with an extra long hose to the tank. It run abt $290 IIRC. Cheaper than the carb. Installation was easy and it worked great. They make a conversion for about everything it looks like.
Turn on propane tank, push prime button, and start generator.