Results 1 to 5 of 5
  1. #1

    Pistons PLEASE HELP!

    Anyone out there who has ever expirenced this please send help! I bought a 99 Polaris SLX 1050 and its a beautiful ski, it ran like crap so first thing was a compression check that revaled the #3 cylinder at 70psi the other two were 130psi. So I tore down #3 and the head was cracked as well as pitted from detonation, the piston was damaged from pitting marks also. I purchased everthing new except for the head because I was told that they were dicontinued so I managed to get one from a junk yard that was in good shape. The ski ran better than great for about 6 total hours then nothing. It seemed I was not getting fuel so I then cleaned the carbs and replaced all of the lines never touching any setting to the screws or anything. The ski now ran for about 2 hours and again died, now the compression on #3 is 100psi #2 is still at 130psi and #1 is now at 100psi. I have torn #3 apart again and I am right back where I began...trashed head and piston and I suspect #1 is the same. Does anyone have advise on what to do and where to get heads for a 99 1050?

  2. #2

    Join Date
    Aug 2006
    Homer Glen Il.
    can you post some pics so we can see the damage .

  3. #3
    As soon as I get home pics will be on!

  4. #4

    Check everything!

    Sounds like you did the basics but if you're tearing up pistons especially eating a hole in the top of them then it's probably too lean or from pre-detonation. Now the trick is finding the root cause.

    Check to see if the crank seals aren't leaking. For this test you block the exhaust and intake ports. I used a 1/4" lexan w/ RTV to seal them off. Then used a the line from the crankcase to the fuel pump to test it to 6 psi to do the leak test. For my SL 750, is was not to lose a 1# per hour. Don't over pressurize it as you can pop the seals out. If it leaks then find the leak,

    In the extreme case the crank could have been hydro locked and the crank is no longer @ 120 degrees from each piston. Now this is from my SL750, not sure for yours.

    Another thing to check is the intake reeds valves. If they aren't good then you'll also run lean.

    Then if you only clean the carb it may need a rebuild kit as well.

    Others may have better Ideas since I don't have your specific PWC.

  5. #5
    Here are the pics
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	IMG00028.jpg 
Views:	48 
Size:	546.2 KB 
ID:	90151   Click image for larger version. 

Name:	IMG00029.jpg 
Views:	48 
Size:	573.5 KB 
ID:	90152  

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Please help!!! Correct piston size ordering.
    By cisco4449 in forum Yamaha PWC Performance (2-stroke)
    Replies: 5
    Last Post: 09-28-2012, 07:02 PM
  2. Trouble with number one piston!!!! Please help
    By Meversole6 in forum Yamaha PWC Performance (2-stroke)
    Replies: 33
    Last Post: 07-26-2012, 12:32 PM
  3. Burned piston. Please help
    By danny boy in forum Polaris Open Discussion
    Replies: 3
    Last Post: 05-21-2011, 07:10 PM
  4. Are these pistons ok? Please help
    By 750slt in forum Polaris Open Discussion
    Replies: 2
    Last Post: 07-06-2009, 05:02 PM
    By CRAZEDRXP in forum Sea Doo Open Discussion
    Replies: 11
    Last Post: 07-05-2005, 09:28 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