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  1. #1

    85,85,55 gp1200 w/low compression

    Low compression after all. I tested starting with front of Hull 85,85,55. The last one is the one we thought was bad so my question is can I get away with pulling head and cylinder and do a top end or do I need to perform some more testing?


  2. #2
    How many hours on the motor?

    Did you use a good compression gauge and tested the motor warm at WOT?

    If low hours I guess you could get away with doing just a top end, need to pull the head and look further. I'm sure some with more experience will chime in. Those numbers are low though

  3. #3
    Motor not warm and kinda older gauge that u hold on not threaded. I checked it because it is bogged at idle and so I thought to check there. I think its around 200 hrs

  4. #4
    slothman's Avatar
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    Quote Originally Posted by MossBack View Post
    Motor not warm and kinda older gauge that u hold on not threaded. I checked it because it is bogged at idle and so I thought to check there. I think its around 200 hrs
    200 hours....might as well do a full rebuild! Pull the heads and see how she looks.

  5. #5
    Quote Originally Posted by slothman View Post
    200 hours....might as well do a full rebuild! Pull the heads and see how she looks.
    Yeah I would pull the motor and at least send out the crank for inspection, maybe true and weld it if its good? Hone the cylinders and get pro-x piston kits for them. New gaskets and seals of course.

    I would wait for a reply from the more experienced people on this forum.

  6. #6
    67x stamped on top the head is that still the same as the 66v or totally different?

  7. #7
    compression #s are low, but the fact that one is way lower than the rest indicates a bad piston/ cylinder. A cold motor should still show at least 100psi across the board. 200 hours is a good run for these engines, I have had 3 of these skis since 1998 and never had an engine last more than 60 hours before a piston melts for some reason.

  8. #8
    Moderator RX951's Avatar
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    Sounds like time for a rebuild to me.
    # 3 squeaked a piston or something. Rebuild the carbs as well.

  9. #9
    K sounds like the winter project. Is there any difference on the 67x?

  10. #10

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    Quote Originally Posted by MossBack View Post
    ......Motor not warm and kinda older gauge that u hold on not threaded....

    Hold on there Tiger!

    You are baseing a complete engine rebuild on a questionable piece of equipment. Check with your friends to find a high quality gauge. It might mean the difference between a carb. rebuild and a complete rebuild.

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