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  1. #1

    Join Date
    Aug 2009

    Crankcase pressure test

    Hi doing the pressure test after top end rebuild. holds 10psi but over that the rear crank lipeal expands and the airpressure bleeds off to 5 psi also if I rotate the engine samething happens. The seal looks visualy good and the spring that holds the seal to the shaft is intact.Should I be worried?
    Also can the crank seals be replaced without splitting the case?

    This is the link to my ordeal with this ski.

  2. #2
    Moderator OsideBill's Avatar
    Join Date
    Mar 2006
    United States
    10 psi is the highest you want to go, If you over pressurize it will blow the seal out. Answer to question two is no you have to split the cases to replace seals.

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