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  1. #1

    Default Onan mcck 6.5 1987

    After sitting for a few years my gen wouldn't start. Had carb cleaned and rebuilt. Gen will start and run great at idle but as soon as load is turned on it starts to hunt a little then runs at a reduced rpm and will backfire after a few minutes then shut down. It will then restart after a few attempts but will not take load. After a couple days, will start perfect and run great for a long time until load is added.
    Ideas????

  2. #2
    Join Date
    Dec 2006
    Location
    Chaumont Bay, N.y., USA
    Posts
    5,194

    Default Re: Onan mcck 6.5 1987

    Ayuh,.... Sounds like fuel starvation,....

    Could be the fuel, the tank, the lines, the fuel pump, or more crap got to the carb,....
    Any Grease is Better,... Than No grease at All....

  3. #3
    Join Date
    Dec 2015
    Location
    maplevalley WA
    Posts
    3,499

    Default Re: Onan mcck 6.5 1987

    I agree go through the fuel system completely starting at the fuel tank. Make sure the pickup tube in the tank is clean and the strainer is clean if present. Replace all rubber hoses and completely clean rebuild the fuel filter. Then you can focus on the carb and engine. Is the governor working properly?
    It takes a nickle to go first class!
    If it aint broke dont fix it!!

  4. #4

    Default Re: Onan mcck 6.5 1987

    Went through entire fuel system last summer from tank to carb, great flow. I'm thinking new carb, found one online. Points and condenser are great as well.
    My mechanic buddy tells me gov. is working good
    Thanks guys

  5. #5
    Join Date
    Dec 2015
    Location
    maplevalley WA
    Posts
    3,499

    Default Re: Onan mcck 6.5 1987

    Have you done a cylinder drop test? Is that a two cylinder? While it is running pull a plug wire and put it back on then do the other one if it stalls then your not firing on the other cylinder. Best I can guess is your engine has horizontal opposing cyclinder? I cannot find a parts diagram anywhere for the MCCK 6.5
    It takes a nickle to go first class!
    If it aint broke dont fix it!!

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