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  1. #1

    1998 Gp800 compression help!

    I am looking at a 98 gp800 waverunner. i did the compression and it was 120 psi in one cylinder and 130psi in the other. just wonder is that compression it to low, and if its time for new pistons. is the 10 psi different to much. please reply thanks.


  2. #2
    This is how I run a jetski shop in the desert nmpeter's Avatar
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    unless the ski is a real bargain move on..10 psi differential is the beginning of the end.

    read up on yamahas..engines for the 800 are pricey..the cyinders are plated..so boring is not really a cheap option

    compression can be lower if the engine has an SBT sticker on the mag side of the cylinders.

    oh yeah...welcome to GH

  3. #3
    Thanks for replying, I ended up not buying it because they were asking 2500 obo.

  4. #4
    This is how I run a jetski shop in the desert nmpeter's Avatar
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    good move, thre are plenty of bargain 2 strokes out there now that the lake meade ban is being enforced. one of our members can arrange for shipping of any ski from any venue..so keep looking around..it's buyers market right now..season is pretty much over is some prts of the county.

    now for $5k or so you can buy a BRAND NEW seadoo spark with a warranty...why spend $2500 on a 15 year old ski with likley engine problems?

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