Lou @RVHabit
Updated: Mar 18, 2020
If you own an Onan RV Generator you know how sensitive their carburetors are. If gas sits in them for as little as a month the carburetor can begin to gum up. This goes for other brands of generators as well but Onan seems to be especially prone to this. The carburetors according Onan cannot be rebuilt. This means excellent maintenance should be followed to keep your Onan in good running condition. It starts with exercising the generator at least monthly under at least a 50% load. I also use Sta-Bil 360 Marine with Vapor Technology in the RVs fuel tank. In addition, I use a cleaning method I discovered from Sea Foam. Its not difficult and states it can clean the carburetor and keep the engine from surging. The video will show step by step how I do this on an Onan RV QG 4000.
First, warm up the generator for 5 minutes. Once warm, clamp off the incoming fuel line and remove it from the generator. Connect a short fuel line to the generator that will reach your fuel container.
In a small fuel container mix 2 parts of gasoline to 1 part of Sea Foam. Run the short fuel line to the container with the Sea Foam mixture.
Prime and start the generator and allow to run for 15 minutes. Turn off the generator and let hot soak for 15 minutes. Restart the generator and run an additional 5 to 10 minutes. You are now done you can reconnect the main fuel line to the generator.
SeaFoam claims this procedure will help loosen gum and varnish, allow the generator to run easier and start easier. It may also clean a carburetor that is already surging from clogging. Good gasoline maintenance is also important and I use the Sta-Bil 360 Marine all year round. Corrosion-X is also an excellent product for preventing and cleaning rust.
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