Small Engine Troubleshooting Problems? Ask a Mechanic Now.
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The onan Generators have very sensitive Carbs. The problem is most likely the Carburetor. How old is the Carb? and how often do you run the Generator?
Its recomended that the Generator be ran under load every 3-4 weeks for an hour at minimum. Under load meaning, run the a/c and such to "make the generator work.
This keeps fuel from getting stale in the carb and creating junk in the jets of the carb.
In most cases if it is the carb your better off replacing it. Rebuild kits are a 50/50 shot.
One way to tell if its the spark plugs or not is to remove the breather and shoot just a very tiny bit carb cleaner into the carb. If it starts up and shuts down again, its not the plugs.
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