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  1. #1
    SpeedFreak
    Join Date
    Jul 2008
    Location
    Fond du lac Wisconsin
    Posts
    220

    Motor is due for rebuild

    Well last weekend I was cruising along at half throttle. And I went to make a left turn. Mid turn my ski killed. Tried to start it and the starter would barely turn the crank. Lifted the seat off and felt the motor, it was warm to the touch. I ended up rowing back to the dock and put it back on the trailer.

    Yesterday got a compression tester and checked it. Cylinder 1 and 3 were at 120 psi with throttle closed. Cylinder 2 was at 25. So rebuild is in order.

    What things do I need to look for when I take it apart? I'm going to take the carbs back apart(did a rebuild on all 3 at the begining of the season) and reclean them. Should I stick with a stock piston or get a coated one? I have some work ahead of me before I can post some pics of what the pistons look like. Also the 2nd plug was black and has metal fragments burnt on it. The other 2 were golden brown.


  2. #2
    Hydrotherapy's Avatar
    Join Date
    Sep 2006
    Location
    The Rock
    Posts
    3,347
    +1
    17
    wow bad luck sorry..

    i think when you get the head off it will be easy to spot from the comment about metal on the plug...it aint going to be pretty in there

    pre-mix or stock auto lube ???

    stick with stock pistons on the rebuild

  3. #3
    SpeedFreak
    Join Date
    Jul 2008
    Location
    Fond du lac Wisconsin
    Posts
    220
    Premix with amsoil. 40:1 Forget what the jetting is at. I'll have to look when I get into it.

  4. #4

    Join Date
    Aug 2007
    Location
    Bridgeton nj
    Posts
    111
    have you been checking plug readings?
    how many hours?
    were the carbs ever jetted or rebuilt?
    did it seem to be running good before it seized?

  5. #5
    SpeedFreak
    Join Date
    Jul 2008
    Location
    Fond du lac Wisconsin
    Posts
    220
    I have been checking plug readings. And it has been running perfectly all year. I have most of the ski took apart now. When I took the header off there was many pieces of metal in the second hole. Tomorrow I will hoist it out and take of the head to see the real damage. I know its going to be bad.

  6. #6
    SpeedFreak
    Join Date
    Jul 2008
    Location
    Fond du lac Wisconsin
    Posts
    220
    Ok got the motor tore apart. Number 2 is shot. But its not from running lean. It looks like the second crank bearing went. And the thrust washers have some big gouges in them. Now I know i'm going to have to get the crank rebuild and cylinder redone. Luckily number 2 does not have huge gouges in the cylinder wall.

    Upon looking at cylinder 1 and 3 the walls look just like number 2 and the pistons have some good size scratches on them. Do I need to redo 1 and 3 as well? Sorry forgot to take a pic of the crank.
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  7. #7

    Join Date
    May 2008
    Location
    Seattle, WA
    Posts
    5
    Please upload a picture of the crank, I would love to see what a bad bearing looks like. I am about to tear down my motor myself.

  8. #8
    Moderated
    Join Date
    Oct 2006
    Posts
    3,711
    time for a 1300 top end

  9. #9
    zpeters's Avatar
    Join Date
    Jul 2008
    Location
    bayville NJ
    Posts
    437
    Oo the joys of that build!

  10. #10

    Join Date
    Jun 2009
    Location
    PR
    Posts
    91
    at least u could row back. when my ski died out in the ocean i had to swim back... one hand pulling the ski and the other swimming

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