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  1. #1

    Need help.. decreased performance.

    I ran the ski with old plugs to let the fog oil out, and changed with new plugs already. Ski has no torque out of the hole and top speed is 45 MPH. Also after warmed up the idle is around 4K. Is this a pump seal issue? Ski vibrates coming up on plane a bit. Iím having a hard time finding the correct seal kit without having to also buy an upgraded intake grate. Can anyone help me out a bit. Thanks!


  2. #2
    How’s your wear ring look? Could be the issue

  3. #3
    My xl700 does about 10 mph. Carbs rebuilt. 150 psi compression. Good spark both cylinders. Wear ring I believe is still in decent shape. Starts up perfect right away. Revs up high on a hose. Put it in the water and has no pop off and no speed. Water pump outlet spits out water like it should. Idk what my problem is.

  4. #4
    Quote Originally Posted by Bigboy7363 View Post
    How’s your wear ring look? Could be the issue
    Alright here’s the issue.. I’m very mechanically inclined and have no problem diving into the disassembly of the ski. I rather have a little insight first as I’ve never wrenched on a ski before. Here’s where people have a hard time sharing their knowledge. Can anyone shed a little light on what needs to be done? Thanks again.

  5. #5
    I think you have bigger issues if ur ski is idling at 4k. A bad pump seal would cait to go to max rpm and cavitate on acceleration. I think something is wrong with your ITBs- sounds like an air leak so check your bypass valve

  6. #6

    Join Date
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    Quote Originally Posted by Bigboy7363 View Post
    My xl700 does about 10 mph. Carbs rebuilt. 150 psi compression. Good spark both cylinders. Wear ring I believe is still in decent shape. Starts up perfect right away. Revs up high on a hose. Put it in the water and has no pop off and no speed. Water pump outlet spits out water like it should. Idk what my problem is.
    what rpm? Rpm and speed are key to diagnosis prop damage, housing out of spec if you can get a sheet of paper between housing a blades you have issues....

  7. #7

    Join Date
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    Quote Originally Posted by MattH View Post
    Alright here’s the issue.. I’m very mechanically inclined and have no problem diving into the disassembly of the ski. I rather have a little insight first as I’ve never wrenched on a ski before. Here’s where people have a hard time sharing their knowledge. Can anyone shed a little light on what needs to be done? Thanks again.

    Get the service manual and have a read also the diagnostic software is like $70 on eBay, but start simple plugs, oil, intake but 4K idle is very high! Trolling speed for an fx ho ( assume that’s your ski) is 1550-1750 according to the manual!

    Impeller clearance should be 0.5mm or less......

  8. #8
    Quote Originally Posted by seabrook View Post
    I think you have bigger issues if ur ski is idling at 4k. A bad pump seal would cait to go to max rpm and cavitate on acceleration. I think something is wrong with your ITBs- sounds like an air leak so check your bypass valve
    I checked the bypass valve with YDS and it chattered when I bump tested it.

  9. #9
    Quote Originally Posted by HDAV View Post
    Get the service manual and have a read also the diagnostic software is like $70 on eBay, but start simple plugs, oil, intake but 4K idle is very high! Trolling speed for an fx ho ( assume that’s your ski) is 1550-1750 according to the manual!

    Impeller clearance should be 0.5mm or less......
    Ski was put away for the winter with fresh oil change and fogged. Brought back out, ran until wam and plugs were changed. YDS caught idle speed high but never said why. Only happens after warmed up and idling, shut it off, restart and everything’s fine. Someone else mentioned a vacuum leak or possible complete TB assembly. I’ve checked all the rubber hoses and they are connected and in good shape.Thanks for the replies.

    So so does anyone have a good write up out there for the pump seal?

  10. #10
    Nobody can provide any advice, videos or have a write up on pump seal? I’m having a hard time even finding the right part.. Can anyone even point me in the right direction for the seal kit? Usually forums are full of helpful information.. Will I have to just dive into this and post pics on a new post in hopes for a better response outcome? Cmon guys help me out.

    Ive read a lot about needing a new ride plate or intake grate with some kits.. some are ok to use stock ride plate. Some require trimming the seal parts.
    Last edited by MattH; 06-09-2019 at 08:00 AM.

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