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  1. #1

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    Sep 2007
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    Motor Rpms Not In Sync

    This Has Been A Problem For Several Months....left Motor Turning 8150+.....right Motor @ 7950+/-...i Am At My Whits End As To Try And Figure This Out.....i Have Ran Dedicated Line To Both The Regulators And Boost Guages, Thinking There Might Be A Lean Condition...thought There Might Be A Boost Leak...but Thats Not It Either....impeller Has Been Repitched Several Times....what Can It Be....help


  2. #2
    Dr Len's Avatar
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    New Jersey Attitude Capital of the World
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    Sounds to me like SC clutch slippage

  3. #3
    JFizzleJR's Avatar
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    Maybe one of the engines is overfilled with oil.

  4. #4

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    Sep 2007
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    Oil Is Dead On....if There Was Slippage...there Would Be Loss Of Boost...

  5. #5
    spd5535's Avatar
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    This is normal on twin engine SeaDoo's; my 150 Hp. engines do the same thing. One of the members tweaked the impeller on the lesser to match the greater and it ran straight as an arrow after that......
    Last edited by spd5535; 07-15-2008 at 10:56 AM.

  6. #6

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    Sep 2007
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    Impellers Have Been Tweaked Several Times......

  7. #7
    cyoungesq's Avatar
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    Apr 2006
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    Bridgeport, CT
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    uneven rpms at WOT

    There have been a few posts on this ... "Vern" from MI, I think, described it most technically...I can't find his post. It's a pump loading issue based upon the hull design and the impellers' rotation in the same direction. The angle of the hull (port vs. stbd) dictates the angle of the intake opening that, in combination with the cork-screw rotation of the impeller (that both turn the same way despite differently angled intake openings) feeds more water on one side than the other One pump gets loaded more than the other based upon angle of pump intake opening, causing the uneven rpms, all other factors equal. A solution is to have differently pitched impellers - pitch one up or down depending on where your rpms are. Trial & error until you get them synched at WOT.

  8. #8

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    Sep 2007
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    albany, ga
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    Will Tweak Some More This Evening.....

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