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  1. #1

    Join Date
    Sep 2011
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    Lynden wa
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    780 running issues. please help.

    I have a 1996 with the fuji triple engine. I rebuilt the carbs because I had a diaphram leaking. I changed the plugs. The ski fires up and runs great the first try. Then shut it off and restart it and it has a major missfire. So I pulled the plugs they seem clean. I put them back in and missfire. So I let it sit overnight started it up it ran great. I shut it off then restarted it and missfire. Does anybody have any idea what could cause this?


  2. #2
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    Oct 2006
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    Misfire or backfire?

    Are you getting spark when it's acting up?

  3. #3

    Join Date
    Sep 2011
    Location
    Lynden wa
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    Well the plug wire tester lights ups on all 3 cylinders. Its got good fuel flow. 130 compression all holes. I don't have any blow back in the carbs, so I don't think a reed valve is broken. Could I have one stuck shut? Missfire but it still revs up. I don't think its in limp mode.

  4. #4
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    Doubt you have a stuck reed. That would be a consistant problem.

    When it acts up, pull 1 plug wire off at a time and look to see which cyl is acting up. If the engine doesn't lose RPM when you remove the boot, that cyl isn't firing.


    CAUTION: don't get between the plug boot and engine or you can get shocked.

  5. #5

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    Sep 2011
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    Lynden wa
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    I figured it out. The fuel return had very little flow through it. I took a little wire and cleaned out the little hole. It had way more flow through it. Hooked the hose back on and no more problems. I'm guessing to much fuel pressure in the carbs and was flooding the cylinders.

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