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  1. #1

    slt 780 center cylinder running way to rich or dead? limited

    96 slt 780. Rebuilt carbs, boyeson pro race reeds, replaced fuel lines, rebuilt fuel pump, etc...was running decent but a little lean on pto cylinder so richened it up a bit. Had pulled heads to check piston wash by the way. After reinstalling heads etc, the ski runs fine on the trailer but in the water sluggish and rpms limited to around 5500 +/-. Checked piston wash again and center cylinder piston is completely clean and soaked. Carb adjustments are pretty close to stock, even reset all the adjusters just to be sure. Clueless as to why its doing this all of a sudden? Any help appreciated!


  2. #2
    Click avatar for tech links/info, donation request K447's Avatar
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    A water leak into the cylinder will steam clean the piston dome. It sometimes looks like very rich fuel pattern but is actually water.

    Check the cylinder head sealing for the water jacket.

  3. #3
    are you talking about water leaking past the head gasket into the cylinder? Here is a pic of the piston, i went ahead and pulled the head again and snapped it.

    Click image for larger version. 

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    Last edited by K447; 07-06-2014 at 09:38 PM.

  4. #4
    Click avatar for tech links/info, donation request K447's Avatar
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    Quote Originally Posted by jasonsmithftw View Post
    are you talking about water leaking past the head gasket into the cylinder? ...
    Yes.

  5. #5
    BlueFishCrisis's Avatar
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    Replace head gaskets.

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