My 2000 motorhome has an Onan generator model 5BGEFA 26100P that I just had serviced at an Onan repair shop. This unit has been trouble since 2009 and at that time the genset was removed from the coach and decarbonized at an Onan shop in Connecticut. It ran for about two days on the way back south.
In 2010, a new fuel pump and new carburetor were installed. It ran OK until I was on a trip north last summer. When I got home, I took it to an Onan repair shop; again a new carburetor. I was told I needed to run this unit two hours twice per month under load and that I also needed to use fuel stabilizer, this to be added each time the unit is not on the road getting gasoline each day. I was also told the new carburetor is the same one Onan has been using since my unit has been built. No change for the 10 percent ethanol gas we now get.
I have not made any contact with Onan on this at this time. I would like to know if other people have this problem, and if running the unit two hours twice per month and using the stabilizer will give me a unit I can count on.
Ed Graveline | Dowling Park, Fla.
The new gas with 10 percent ethanol has been causing a lot of problems with small engines. The tiny jets gum up readily when this fuel sits in the carburetors too long. Keep in mind that even though you are using gasoline and putting fresh gas in the main tank when you are traveling, if you are not using the generator, the old gas sits in the genset’s pump, carburetor, filter and fuel lines going to the tank and deteriorates until the jets and passages are clogged.
Some shops, as a matter of policy or expediency (and high labor rates), replace gummed-up carburetors rather than attempt to clean them. There is a new product from Gold Eagle, the makers of STA-BIL fuel stabilizer, called Start Your Engines! that is designed to help clear gum from carburetors if the generator will run at all. You might want to try this before paying for repairs.
All manufacturers require that the generator is exercised (run under load)every month, even if you don’t need the electricity. Although it is more work, you can run it long enough to get the old gas out of the filter and fuel lines.
Try shutting off the fuel to it and running it dry until it stalls when you’re done with it until it is time to exercise it again. Adding fuel stabilizer in the main gas tank is not necessary if you are using the generator regularly.
— Ken Freund