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  1. #1

    Horrible low end bog, rebuilt carbs, no fuel flapper, few mods...

    I bought the ski (2000 gp12r) and as soon as i got it on the water, when i hit WOT at anything under 3k rpms the engine just bogs down, does not usually die but slowly accelerates. So i tore into the carbs, rebuilt them, removed the fuel flapper. When i turn the ski off the pv valves move twice, with the seat off on the water i gave it a little gas i did not see them move. The ski has a d plate, jet works bypass. Compression shows 120 121 121 on cylinders. Plugs look good.

    Is there a way to test the pv system without having to buy a new servo motor?, or is there something more simple i should be looking into. The ski seems just fine at anything above 4k rpm, i got it up to 65 on stock speedo today.


  2. #2
    I have a GP800 and know nothing about it its my fall back ski when nothing else wants to run. But it makes those adjustments on shut down as well. I would look elsewhere.sounds to me like the carbs needs tuned.

  3. #3
    If anyone in the Northwest (portland, OR) area can help me out i would be willing to pay.. i want to get my ski on the water with no problems this summer :-/

  4. #4

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    have you tried fattening up the low speed jets?

  5. #5
    Moderator OsideBill's Avatar
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    sounds to me like the powervalves are stuck open. does not work until you hit 4k rpm's then runs great, this is classic PV issue.

  6. #6
    If they are stuck open can i close them and test that it works better on the bottom end? Or should i replace the servo that controls them?

  7. #7
    TX21's Avatar
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    Quote Originally Posted by soulraver View Post
    If they are stuck open can i close them and test that it works better on the bottom end? Or should i replace the servo that controls them?
    Yeah uplug the servo motor and close them then go run it. Should be great on bottom and crap on top end.

  8. #8
    Might be a stupid question but how do i close them.. i mean i can figure out how to actually do it but which way do i know is closed vs open ?

  9. #9

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    looking at the power valve wheel from the back of the ski, turning the wheel clockwise is closed and ccw is open

  10. #10
    Thank you for the quick reply.. before i did that i decided to open up one of the pv covers.. this is what i found.. i know its my first time with a pv engine but i know this can't be right, lots of gunk and such.. the pv's move fine left right when unhooked, but i don't see them moving when on the water, could this be the problem? what should i do about this ?Click image for larger version. 

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