Results 1 to 7 of 7
  1. #1

    Read My Piston Damage!

    Here is a pic of my OTO pistin. The arrow on the left points to a 3/8 piece of the top ring that is melted to the piston. The right arrow is the locating pin that is no longer there. The side of the ring appears (to me) to reflecct the scaring of the pin as it was drug up and down the piston side. Amazingly, the cylinder wall has an ever so slight mark that will be removed by a minor honing.

    From what I have read on the forums, the top of the piston looks like it was way to lean! The other two pistons were completely covered with dark soot, but fine otherwise. There were no signs of any piston wash on any piston!Click image for larger version. 

Name:	PtoPiston.jpg 
Views:	54 
Size:	42.0 KB 
ID:	252673

    I am currently rebuilding the entire engine. '93 SL650. Am I correct in my read of the piston?


  2. #2
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
    Join Date
    Oct 2006
    Location
    Cleveland OH
    Posts
    17,330
    +1
    31
    It doesn't appear to me to be a melted ring. But could it possibly be the actual locating pin?

  3. #3

    Join Date
    Aug 2006
    Location
    Homer Glen Il.
    Posts
    8,704
    +1
    109
    I ave a 785 piston just like that and really never thought about what had happened to it Very weird , time to see what Jay or Randy think

  4. #4
    TEAM BRONX TECH FAT BOY's Avatar
    Join Date
    Mar 2009
    Location
    Bronx, NY
    Posts
    353
    O had this happen on a seadoo 951 motor. The set pin fell out and the ring eventually tagged a port. Surprisingly I got away with a hone.

  5. #5

    better Picture

    Here is a better/closer picture of the ring etc. I hope I did it right..can't see the pic right now!
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Piston2.jpg 
Views:	97 
Size:	62.2 KB 
ID:	252755  

  6. #6
    casey67's Avatar
    Join Date
    Sep 2006
    Location
    Lemont,IL
    Posts
    2,571
    +1
    35
    It looks like the upper ring pin is at the end of that ring. Where the top arrow (peice of ring) is pointing.

  7. #7

    casey67 is right - my mistake

    I pryed the broken ring out and I was wrong. The upper pin is at the left side of the broken ring. Not sure what caused the gouge in the piston. Possibly just crud from the top of the piston? The reed cage from that piston (the metal reed stops) have the same crud on them. All the reeds, however, are in perfect shape and are the originals?

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. What caused the damage to my piston? Pics Inside
    By geoffw in forum Sea Doo Sport Boats
    Replies: 3
    Last Post: 08-11-2011, 01:05 PM
  2. I need help reading piston damage.
    By DockJockey in forum Sea Doo Open Discussion
    Replies: 5
    Last Post: 08-04-2011, 04:30 PM
  3. Pics of my pistons....not a pretty sight
    By Tony in forum Polaris Open Discussion
    Replies: 18
    Last Post: 06-17-2007, 11:29 PM
  4. look at my pistons(efi guru's)
    By txgp1300r in forum Yamaha PWC Performance (2-stroke)
    Replies: 6
    Last Post: 08-11-2006, 09:27 AM
  5. My Ceramic Damage
    By Franko in forum 4-Tec Performance
    Replies: 4
    Last Post: 07-24-2005, 08:23 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
  •