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  1. #1

    slt 780 idle question?

    My 97 slt780 runs great but idles rough and the motor shakes alot when idling or a low revs.

    Is this normal or do I have a problem somewhere like low speed jets out of adjustment?


  2. #2
    Moderator beerdart's Avatar
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    What RPM are you idling at?

  3. #3
    johnsonmtz's Avatar
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    I believe the spec is for idle between 1200 and 1400 RPM.

  4. #4
    Well right now I do not have a MFD but it idles at about 2mph and the motor shakes pretty bad from idle up till around half throttle then it runs great.

    I have tried adjusting the slow jets but no change.

    Are these motors supposed to shake at low rpms?

  5. #5
    la90043's Avatar
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    use your low speed screw to adjust the idle. start at factory spec.

    then probably you'll need to screw them in just a tad. no more than 1/8 screw in after setting at factory specification. that can better the rough idle. if idle is better and the pwc starts fairly easy then you're very close.

    if rough idle throughout low rpm to mid rpm it can also be the drive shaft is out of alignment......................................... .

    or a combination of both.......................................

  6. #6
    I was also thinking it could be the driveshaft. How do you go about fixing a out of balance driveshaft? Do you have to just buy a new one?

  7. #7
    johnsonmtz's Avatar
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    Has the drive shaft ever been removed? There is a little rubber bump stop that sets inside the coupler where the shaft is suppose to press against. If that is missing you can get a bit of front to back play that will make some knocking noise.

    I don't know the reason why, but at idle these Polaris skis do make a bunch of racket. But, once the driveline is under load, everything hooks up and noise goes away.

    KJ

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