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  1. #1
    XP NUT
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    Help Seadoo 787 Question

    Ok boys. I did it to myself. Now I need some help. I just installed a new engine in my 97 xp and I removed the rotor from the flywheel and did not mark it. Put motor back in and definite timing issue. Rotary valve is correct. Please let me know how to reinstall the rotor to flywheel. Thank You!


  2. #2
    This is how I run a jetski shop in the desert nmpeter's Avatar
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    you need a quality TDC guage, a degree wheel, a timing light and a seadoo shop manual to have any chance of getting it right.

    You'll also need to fabricate a pointer setup to bolt on to the rear of the engine. You find TDC and mark it on the PTO with a scribe, then use the degree wheel to get the timing set approx. You can fine tune with an mpem programmer, or play the on/off game with the stator cover till you get it right.

    Given the one time inve$tment that has to be made here..you might simply chalk it up to newbeness and pop for a used flywheel assembly.

    my mantra..if it doesn't HAVE to come off..leave it alone..nothing good comes of removing bolts without knowing exactly why you are doing it.

    I assume you wewre trying to use a third party flywheel puller..I nearly made the same mistake the first time I had to remove one.

  3. #3
    96XPSS's Avatar
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    Quote Originally Posted by nmpeter View Post
    you need a quality TDC guage, a degree wheel, a timing light and a seadoo shop manual to have any chance of getting it right.

    You'll also need to fabricate a pointer setup to bolt on to the rear of the engine. You find TDC and mark it on the PTO with a scribe, then use the degree wheel to get the timing set approx. You can fine tune with an mpem programmer, or play the on/off game with the stator cover till you get it right.

    Given the one time inve$tment that has to be made here..you might simply chalk it up to newbeness and pop for a used flywheel assembly.

    my mantra..if it doesn't HAVE to come off..leave it alone..nothing good comes of removing bolts without knowing exactly why you are doing it.

    I assume you wewre trying to use a third party flywheel puller..I nearly made the same mistake the first time I had to remove one.
    Dude, he won't need any of that. Get a manual (can download here) and it will show the location for the magneto in relation to the flywheel keyway.

  4. #4
    XP NUT
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    Wait. There are only 6 possible positions. I have a fancy seadoo book, the tech book, nothing on the position in it.

  5. #5
    aseymore aseymore's Avatar
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    you must align one of the protuberance end of the magento rotor withe hole in the flywheel.

    Look on the outside of the magento rotor and you will see a piece of metal on the outside of it sticking up about 1/8 inch thick and about inch to inch and half long. Rotate the magento rotor on the flywheel until the right side of it lines up with the hole in the flywheel right above the magento rotor. All of the timing is done in the mpem. After that you will have to check your timing with the timing light and a degree tape. Find TDC of the mag piston and make a mark on the PTO. You will need to make a pointer to atach to the rear of the engine and line up with the mark you made on the PTO. Make a loop on the other end and mount it behind the cradle bolt to secure it. I make one out ot a piece of welding rod and sharpen the end to make a point then bend it to line up with the mark on the PTO. Ir it lines up perfect you should be in time if not this is where you will need the degree tape to see how many degrees it is off and will have to take to a dealer and have him to adjust timing in the MPEM. I think i got every thing right.

    Aubrey

  6. #6
    aseymore aseymore's Avatar
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    Forgot to mention that it show it very clear in my shop manual.

  7. #7
    aseymore aseymore's Avatar
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    After reading my response I see that I left out one thing. After you find tdc. Rotate the pto flywheel clockwise,when facing it until piston is at 3.33 mm. (.133in.) before top dead center. Make a mark on the ptp flywheel aligned with timing mark pointer. Remove the tdc gauge, reconect spark plugs wires
    Now you will need a good tack that is acurate, not the one that came on the ski. Conect the timing light to the mag side spark plug wire. Rev the engine to 3500 rpms and shine on timing mark pointer you make. If pointer and mark are perfecly aligned you are in time. If not you will need the degree tape so you can see exactky how much you are off. If you don't have a adjustable timing module similar to the MSD 4255 Enhanser where you can adj. timing yoursels you will have to take to a dealer and let them set it for you.

    Aubrey
    Last edited by aseymore; 08-18-2009 at 01:22 AM. Reason: left out something

  8. #8
    XP NUT
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    WOW

    I am so confused. Thank Yu for all your help. I am going to try to figure this out tonight.

  9. #9
    This is how I run a jetski shop in the desert nmpeter's Avatar
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    save yourself the time and expense of tooling up for this job, buck up and just buy a used flywheel assembly from ebay, looks like $75 will do it, a good TDC guage could cost you that much ( some yahoo is selling an "offical" seadoo tdc guage for $175(dw)and then you _still_ might have to take it to a dealer to get the timing just right via mpem programming. Not having the timing right will cost loads more in the long run.

  10. #10
    aseymore aseymore's Avatar
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    http://www.greenhulk.net/forums/atta...1&d=1250619749

    Go to the attachment the picture may help.

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