Results 1 to 5 of 5
  1. #1
    Moocher of Skis The River Skank's Avatar
    Join Date
    Sep 2010
    Location
    St. Charles, MO
    Posts
    58
    +1
    2

    The lets figure out what happend to piston #1 thread

    This is a rebuilt motor by a local shop. Ski had around 65hrs on it since rebuild. Oil lines all look good, piston 2 and 3 still look great. Carbs are on the way back from Bill. Looks like just some minor corrosion from water in fuel. Looking for more ideas to check on why this piston went. Been discussing probable causes with Jan(jkr1300) but we havnt found a smoking gun as of yet. Hoping someone here can chime in with some good ideas of what happened. 2 strokes are not really my thing so please explain ideas if you can. Thanks


    #1 carb


    exhaust side of piston


    top view of piston



    exhaust side, top shot of piston


    top shot with jug off


    intake port #1 Cylinder


    minor amount of oil under the airbox



    intake side of piston


    pic of jug with no piston



  2. #2
    Moderator beerdart's Avatar
    Join Date
    Aug 2006
    Location
    CT
    Posts
    25,929
    +1
    1,407
    It looks like you spun a ring and it grabbed the exhaust port.

  3. #3
    Superman! fivespeedsteed's Avatar
    Join Date
    May 2010
    Location
    Midlothian VA
    Posts
    1,058
    +1
    14
    beerdarts theory sounds pretty accurate. i thought the powervalve was pretty close, but then i saw that it looks like its still being held up by the pin. if you touch that powervalve its not floating around in its trough freely is it?

    if the pv is there it was probably a ring jumping its locator pin

  4. #4
    Myself's Avatar
    Join Date
    May 2007
    Location
    North Central Arkansas
    Posts
    2,771
    +1
    129
    Besides the spun ring theory, my only other guess would be an air leak at the exhaust powervalve or manifold. If a 2-stroke has an air leak on the exhaust side it will burn up the side of the piston and it looks very similar to that. Going back to my dirtbike days.

  5. #5
    Happily Self-Employed WFO's Avatar
    Join Date
    Nov 2005
    Location
    Houston, Texas
    Posts
    12,801
    +1
    450
    the ring spun and caught the exhaust port

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Tryin to figure out what this stator goes too?
    By polarisjunky in forum Polaris Open Discussion
    Replies: 1
    Last Post: 06-24-2013, 02:56 PM
  2. Replies: 11
    Last Post: 05-16-2013, 09:34 PM
  3. Need help figuring out what and how to replace a part
    By tkey3425 in forum 2-Stroke Performance
    Replies: 2
    Last Post: 11-11-2010, 09:21 AM
  4. Think I figured out what the Rotax Racing ECU does with the speedo
    By boostaholic in forum 4-Tec Performance
    Replies: 4
    Last Post: 08-24-2008, 11:44 AM
  5. Replies: 0
    Last Post: 07-19-2008, 09:18 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •