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  1. #1
    dsgamermike's Avatar
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    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
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    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.
    Dustin

  3. #3
    dsgamermike's Avatar
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    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
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    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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