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  1. #11
    johnsonmtz's Avatar
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    Quote Originally Posted by BlueFishCrisis View Post
    Have you checked the tops of the pistons for wash?
    Definitely need to see piston wash to determine lean or rich. Plug chops can be misleading.

    Have you removed your plug wires from the boots, cut 1/4" and reinstalled on the boot? Poor conductivity to the plug through this connection can cause goofy plug readings.


  2. #12

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    If fact I did cut back the wire to fresh copper and twisted the boots back on!

    I tried with my cheap usb bore cam to see the pistons in the bright sun and I could not...

    For wash, does it have to be done after wide open run or?

    The plugs actually get wet idling and slow speed. The full speed runs are what may be lean?

  3. #13
    johnsonmtz's Avatar
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    Piston wash doesn't need a high speed run. Put the cylinder at BDC and with your bore scope you should be able to see dome of the piston very well. Good wash will have clean aluminum areas about the size of a fingernail at the intake ports and the rest of the dome black. Since you lost 150RPM when you richened the PTO cylinder I'd guess that it was okay and the excess fuel has decreased performance. Try and get a picture of your wash to post them and we can go from there.

    AS far as wet plugs at idle.....I don't think it matters much. How often do you really run these at idle or slow speed? If it's anything like my skis my kids usually have a kungfu grip on the throttle ripping it at WOT. They slow down for bridges and that's about it.

    You can toy with the low speed needle a little and see if it helps. Turn the needle in 1/8 turn then see if you still have good throttle response. Keep doing this until you grab the throttle and it stumbles on it's face, then go back to the last good position.

  4. #14

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    Finally Took Cylinder Pictures!!!


    MAG


    CEN


    PTO

    I finally am getting back into watercraft. I took the pictures today of the tops of the pistons.

    I was reading the MAG cyl. lean, the other two ok.

    How do these look?

    Thanks all!!!
    Quote Originally Posted by johnsonmtz View Post
    Piston wash doesn't need a high speed run. Put the cylinder at BDC and with your bore scope you should be able to see dome of the piston very well. Good wash will have clean aluminum areas about the size of a fingernail at the intake ports and the rest of the dome black. Since you lost 150RPM when you richened the PTO cylinder I'd guess that it was okay and the excess fuel has decreased performance. Try and get a picture of your wash to post them and we can go from there.

    AS far as wet plugs at idle.....I don't think it matters much. How often do you really run these at idle or slow speed? If it's anything like my skis my kids usually have a kungfu grip on the throttle ripping it at WOT. They slow down for bridges and that's about it.

    You can toy with the low speed needle a little and see if it helps. Turn the needle in 1/8 turn then see if you still have good throttle response. Keep doing this until you grab the throttle and it stumbles on it's face, then go back to the last good position.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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  5. #15
    Click avatar for tech links/info K447's Avatar
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    Is that an erosion crater visible in the middle of the PTO piston?

    If yes, that cylinder might be running lean, or it WAS running lean in the past?

  6. #16

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    Keith,

    I will have to put you on the payroll...

    When I got this one, it ran like shit. The erosion in the center of the piston was before I owned it.

    I rebuilt the carbs and it rocks out now.

    The questions I had were around the plug readings and how does the wash look?

    Is this rich, lean or ok???

    I am hoping I can run that piston for a while since the lean issues (single outlet fuel pump and super dirty carbs are done)...

    I just worried it was too lean.

  7. #17
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
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    PTO perfect if you want max performance. A tad lean if you want reliability

    CEN too lean. Richen it up to at least match the PTO.

    MAG a tad rich for max performance, but perfect for a good reliable runner.

    For a recreation ski, duplicate the MAG piston wash for all 3 and enjoy it.

  8. #18

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    Quote Originally Posted by xlint89 View Post
    PTO perfect if you want max performance. A tad lean if you want reliability

    CEN too lean. Richen it up to at least match the PTO.

    MAG a tad rich for max performance, but perfect for a good reliable runner.

    For a recreation ski, duplicate the MAG piston wash for all 3 and enjoy it.
    Thank you all!

    So stock settings are just too lean. I will richen the other two!

  9. #19

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    Quote Originally Posted by xlint89 View Post
    PTO perfect if you want max performance. A tad lean if you want reliability

    CEN too lean. Richen it up to at least match the PTO.

    MAG a tad rich for max performance, but perfect for a good reliable runner.

    For a recreation ski, duplicate the MAG piston wash for all 3 and enjoy it.
    For the future, can you explain? The pictures look close to me...

    Thanks!

  10. #20

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    Also, I am wondering if I should just bump up all three main jets vs. HS needles. Not sure what to do when?

    Here's where I am at...

    (ls/hs settings)

    MAG CEN PTO
    1/2.5 1/1 1/1.75

    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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