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  1. #1
    race24x's Avatar
    Join Date
    May 2007
    Fayette, Maine

    98 XPL surging at WOT

    I have a 98 XPL jet kit Pro K filters with a 15/20 Concord impeller. I put in a new wear ring and the impeller from stock from the last ride, but I dont beleive that is causing my issue. It was running great before nice chocolate brown plugs etc 61 on GPS. Now it feels like it is surging good power then looses some for about 1 second maybe 2 then runs good for 15 -20 seconds just feels like it was running out of fuel wide open so I did a couple plug chops and they look lean. Light brown on PTO side and almost grey on stator side. I pulled carbs and tried turning high speeds out (I think you can go 1/2 turn with the caps on I went 1/4 turn (left or out is richen right?) Still plugs looked lean and surge still there. I pulled the ski out I am going to start at cleaning the carbs. I already replaced all the fuel lines from last time and it has been running very good for about 2 months.

    1. How often should you have to clean the carbs?
    2. Who's idea was it to put that high speed screw there it sucks LOL loosen is richen correct?
    3. The impeller and wear ring wouldnt make any difference would they?
    4. The filter up on the bulkhead (I think maybe water fule seperator) should you empty that often or something I can do better?

  2. #2
    Master of the Dooniverse
    Join Date
    May 2006
    Schenectady, Ny
    you can pull those stupid black caps off and toss them out if you liike. none of my mod skis carbs have those caps.

    a lean ski will cut out briefly when running WOT, so i don't think the surge is being lean. hard to say without knowing what you have in those carbs for sure.

  3. #3
    For the list of questions hehe...
    - the impeller being stock will have a difference over performance from the aftermarket. It could be holeshot, top end or both depending on how the old impeller was meant to perform. As long as the wear ring is in good shape there shouldn't be any issues there.
    - carb cleaning is dependent on how much crap or water is in the fuel. Also by what doesn't get stopped by the fuel pick-up filter screen in the tank or the fuel separator. The separator is easy to clean so it's never a bad idea to do so if you think it's a fuel related issue.
    - yeah loosening the high or low screws enrichens the carburetion. Who knows who figured out the placement of the screws...engineers for these things should have to be mechanics for 4 years first before becoming an engineer...just so they know how it is for the repair world when they design this stuff
    Something to think about in regards to the're right, grey is not good...but keep in mind if you're running with injection the lean problem may not be the high speed could be a partially blocked oiler port in the manifold or pump. Or you may have a leaking carb gasket letting in too much air. On the other side of it...if you're opening the high speed screw by a fair amount, you may be giving it too much fuel and could wash the cylinder leaning out or totally taking away what little oil is there.
    Last edited by Schwarzenegger; 08-11-2008 at 06:41 PM.

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