Page 1 of 2 1 2 LastLast
Results 1 to 10 of 19
  1. #1
    cameron da river rat's Avatar
    Join Date
    Sep 2006
    Location
    college station, tx
    Posts
    256

    polaris 1200 issues?

    i rebuilt a genesis 1200 top end for it to only last about 15 hours and the rear piston went. the rebuild was done right, the other two pistons are perfect, could it be from lean injector or since its the last injector on the line it may be starved for fuel like their early 650/750 tripple carb setups?

    can i switch to carbs? and if so, what all is involved or is it worth it? are all 1200 cylinders and pistons the same? i would like to buy some extra parts to bore and match the rear to the other two but the cylinders on ebay that say 1200 dont look like the ones i have? i know the heads are different.

    anyway, i rebuilt it useing wsm rebuild kit w/all new gaskets, leak down tested and passed, i was told on pwctoday that the engine got water in the rear cylinder through the exhaust port? i showd pics of the piston on there. i dont know how that is but i dont want to rebuild it for it to do it again. the kit did not come with manifold gaskets but was just rtv'd to the cylinders so thats what i used was high heat rtv and i had to really pry the manifold off to get it to unseat so i know it was sealed on there pretty good. i used ultra black high heat rtv on it. broke it in real good as well.


  2. #2
    HI! Welcome!! Zig is a good guy! Can you post your pic's? it might help these guy's trouble shoot! Z

  3. #3
    cameron da river rat's Avatar
    Join Date
    Sep 2006
    Location
    college station, tx
    Posts
    256
    when i get home i'll load a pic, it looks nasty...........was water a problem from the exhaust area?

  4. #4
    ph2ocraft's Avatar
    Join Date
    Apr 2006
    Location
    Campbell, Ca.
    Posts
    14,100
    +1
    105
    Hi cameron good to see you, some picts will help TONS.

  5. #5
    cameron da river rat's Avatar
    Join Date
    Sep 2006
    Location
    college station, tx
    Posts
    256
    heres whats left....................

    looks like old fashioned deto to me but im not a pro. the owner, a friend of mine says she was wot pretty much all day pulling a large tube w/three people on it, and at the end of the day, she said it would only go about 40 by herself. all cylinders were at 130#'s before and the other two still are.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	000_0755.JPG 
Views:	103 
Size:	1.09 MB 
ID:	7649  
    Last edited by cameron da river rat; 09-05-2006 at 03:47 PM.

  6. #6
    cameron da river rat's Avatar
    Join Date
    Sep 2006
    Location
    college station, tx
    Posts
    256
    any guesses?

  7. #7
    800AMSOIL4U's Avatar
    Join Date
    Aug 2006
    Location
    Morgan Hill, CA
    Posts
    5,024
    +1
    132
    See if you can get in touch with Randy at www.watcon.com
    Get some more pictures of the whole piston, including the bottom and the cylinder. With some close up pictures.

  8. #8
    Connecticut CrazyA's Avatar
    Join Date
    Nov 2005
    Location
    CT.
    Posts
    8,141
    +1
    1,051
    Possible water intrusion. Did you have a coolant leak anywhere that you know of? Water cooling the piston can cause it to become brittle and the rest is history....
    Does it look like your exhaust manifold was leaking?

  9. #9
    Connecticut CrazyA's Avatar
    Join Date
    Nov 2005
    Location
    CT.
    Posts
    8,141
    +1
    1,051
    Sorry, I just reread your original post a little better. When you reassembled the motor the first time, did you bolt up the exhaust manifold BEFORE you torqued down the jugs to make sure you had proper cylinder to exhaust manifold alignment?
    Sure kinda looks like that damaged part of the piston is "water-washed" clean.

  10. #10
    cameron da river rat's Avatar
    Join Date
    Sep 2006
    Location
    college station, tx
    Posts
    256
    i cant torque down the cylinders with the exh manifold on. or at least i dont have the tools to do it. yes, exh bolts were torqued down and i could see no signs of water intrusion but you never know. i was told to true the manifold which i will, and use gaskets, which i will.

    why would you need alignment when the cases are studed?
    i will try it again and see what happens.
    usually, the water leak engines ive taken apart were washed clean but the whole piston was clean. but thats why im here, to see what caused it and try to fix it.

Page 1 of 2 1 2 LastLast

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. polaris 1200 TXI start/Stop button issue
    By 1200TXI in forum Polaris How To & FAQs
    Replies: 3
    Last Post: 07-14-2016, 11:01 AM
  2. Replies: 29
    Last Post: 09-16-2014, 05:51 PM
  3. Polaris 800 di and polaris 1200 di running issues
    By jetskigreg in forum Polaris Open Discussion
    Replies: 3
    Last Post: 08-17-2011, 11:59 AM
  4. 2000 Polaris pro 1200 Issue no idea???
    By rdizz81 in forum Polaris Open Discussion
    Replies: 6
    Last Post: 05-17-2010, 08:12 PM
  5. GP 1200 Issues
    By murzwern in forum Yamaha Open Discussion
    Replies: 10
    Last Post: 12-28-2006, 06:02 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
  •