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mcal63775's avatar
mcal63775
Explorer
Jan 25, 2015

not getting fuel to carb on Onan generator

Onan Marquis 7000 it started rough but it cleared itself out after a minute or so. Ran smooth for 10 minutes under a light load powering a small space heater and running microwave and all the interior lights on. Then it started to bog down for 3 seconds, recover , run 30 sec. bog down again, run 30 sec. bog down and eventually died. Have not been able to get it to run since. I pulled off fuel line to filter and no gas came out of filter or the fuel line. I used starting fluid to get gen to run, squirting enough to keep gen running, expecting fuel to come out of fuel line. No fuel. Is there an external fuel pump for my generator? or is it an electronic pump? Generator gets its fuel from main tank of MH.
  • Tap on the little fuel pump and/or remove it and try to clean it out. Use marvel mystery oil while cleaing it. May be simple. Check the voltage going to the pump as well.
  • The year and model of your generator would go a long way toward people being able to help you.
  • I found the electric pump...right by the starter that I took out last fall,and cussed so much to get to. I had to drop my fuel tank several years ago to replace fuel pump. Can't cut hole in floor, due to my fresh water tank sits over where fuel tank is. Ugghh. I am not looking forward to this chore. If I got to tear into it that deep, new lines and a pump will be done. ANY volunteers?
  • On mine, the proof was when I disconnected the feed from the tank and hooked a fuel line directly to the pump inlet, and dipped it in a 2.5 gallon gas can. The generator fired right up. After some period of denial and trying other things I came to the realization that it was the rubber line.

    On mine - and yours may be totally different - there is steel line that runs from the generator to some random point under the chassis where it turns to rubber. The rubber line then connects to the pickup at the top of the tank. That rubber line was shot. I couldn't get my tank out so I had to cut a hole in the floor to get at it. It wasn't pretty, but it was an opportunity to install tile in place of the hideous carpet in that area.
  • 97 Coachmen F-53. Well crap. I guess its going to be a fuel line or the pump. Oh how fun this ought to be.
  • What year MOHO? On my '84, the rubber lines had deteriorated and were sucking air rather than fuel. I had to replace the line from the genny to the tank. You might also want to check the fuel filter and make sure the fuel pump is running.
  • Got plenty of fuel in tank. I have not read where someone else had the same problem. I guess I better chase down fuel line from filter and see where it leads me to. Probably to a pump that I can't get to. I wonder Is there a fuse to check for the pump.
  • if this is on a MH?? most have a safty shut down IF the fuel tank is at a quarter of a tank.
  • My 6.5 has an electric fuel pump too. It will run out of gas if the MH tank is below 1/4.
  • MY Onan 4K has an electric pump attached to the generator. It's right before the filter. Speaking of which, I need to replace that filter.