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  1. #1

    98 GP1200 running poorly

    We have a 98 GP 1200 running poorly. Even though it starts fine, and runs well in test (on land). As soon as we put it in, and try to run in the upper rpms the engine quits. It acts like its running out of gas. We've cleaned the carbs, and replaced the gas filter. Has anyone experenced similar problems?


  2. #2
    DAGO RACING CREW 97GPSLEEPER's Avatar
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    You may be experienced a lean seizure on the top end. Try richening your high speed adjustment screws on the carbs.

  3. #3
    I appreciate the reply, I thought of that but then I questioned, wouldn't that be set orignially at the factory? Why or how would that adjustment have changed?

  4. #4
    RHeller1's Avatar
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    have you checked compression?

  5. #5
    DAGO RACING CREW 97GPSLEEPER's Avatar
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    Quote Originally Posted by Stray View Post
    I appreciate the reply, I thought of that but then I questioned, wouldn't that be set orignially at the factory? Why or how would that adjustment have changed?
    It should be adjusted properly from the factory, however, are you the original owner of the ski?

    Also, if the carbs have never been rebuilt, it is definetly time to rebuild the carbs.

  6. #6
    No I am not the original owner, so it stands to reason that the first owner could have reset the idle.

    As for the second part, how often do you have to rebuild the carbs on that machine?

  7. #7
    Quote Originally Posted by Stray View Post
    No I am not the original owner, so it stands to reason that the first owner could have reset the idle.

    As for the second part, how often do you have to rebuild the carbs on that machine?
    Never if you run it all the time. Its when the fuel sits in the carbs for a long time then they get gummed up. If the ski has been sitting for a few months I would say its a good idea to atleast open them up and see if they are clean if they are gummed up you need to rebuild all three.

  8. #8
    Just finished ckecking compression. No joy 1&3 measured 120, 2 measured 0. The piston in cylinder 2 is moving up and down, I'm wondering if I have a valve problems. Any suggestions?

    Thanks

  9. #9
    DAGO RACING CREW 97GPSLEEPER's Avatar
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    You don't have valves in a two stroke. Pull the head, I am sure the piston and cylinder are scored.

  10. #10

    Piston Scored

    The number 1 & 3 Pistons look ok, the number 2 is scored and broken. Would this be indicative of a carb failure, or that there wasn't enough oil getting to the cylinder?

    I've had a tech tell me that the carb could have caused this. That they sometimes run lean, and score the piston. I think it is more probable that the oil wasn't getting to the cylinder.

    Regardless, it seems that the most prudent course of action is to replace the engine.

    The question now becomes, where do I find a rebuilt engine, and which company should I purchase it from (& why). Any advice would be greatly appreciated.

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