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  1. #1
    dsgamermike's Avatar
    Join Date
    Oct 2010
    Lake Norman, NC

    787 with 140 psi compression

    Hey ya'll. I have a 97 seadoo XP with the 787. I have about 140 mag and 143 pto compression. From what I read, a new engine/rebuilt should be about 155. Is it time to rebuild mine, or can I get another season out of it? The motor is anywhere between 2 and 4 years old. Last fall when I bought it, I think I saw 145 on each cylinder. It's been on the water multiple times since then.

    What all is involved in a rebuild? New rings? New gaskets? Anything else?

  2. #2

    Join Date
    Apr 2011
    Emporia, KS
    Did you do the test with the engine warm? Typically you would bore the cylinders to the next size bigger. You will need new pistons, rings, needle bearings, base gaskets, o-rings for the head. Factory pistons are the way to go.

  3. #3
    dsgamermike's Avatar
    Join Date
    Oct 2010
    Lake Norman, NC
    Yes, the engine was ran for about 60 seconds before I took the test.
    And the battery was topped off.

  4. #4
    flyin' the friendly skies airbornexp's Avatar
    Join Date
    Aug 2007
    Mahomet, Il. USA
    run it till it dies. as long as you have comparable compression your good to go. it could also be your gauge depending if its a cheapy or a real one

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