Page 1 of 2 1 2 LastLast
Results 1 to 10 of 19
  1. #1
    silvercrxsir's Avatar
    Join Date
    Sep 2011
    Location
    ocala,fl
    Posts
    334
    +1
    8

    so its not bad gas its a little more serious than that

    On my 99 gp800 I was having issues with it running bad and thought it was gas got it all flushed and refueld and ran it but still seemed weak then lost power and I realized cyl 1 got weak so I pulled the head to find that something happened in the top of the cyl and beat the hell out of the piston and head and put big gouges in the cylinder wall no parts or pieces were found in the manifold or stinger haven't pulled the muffler yet no damage to spark plug at all or in the dome of the head just looks just huge Sharp gouges everywhere have no clue what caused this pv is fine no marks or chips so it wasn't a pv issue nothin in crankcase except for a lol metallilic dust and I can't get the piston outta the jug when it hits the bottom is it possible a ring landing broke and got in the top and caused this any other ideas


  2. #2
    silvercrxsir's Avatar
    Join Date
    Sep 2011
    Location
    ocala,fl
    Posts
    334
    +1
    8
    Sorry I posted this thread twice somehow if someone can remove the other one it would be appreciated

  3. #3
    crashhard's Avatar
    Join Date
    Jul 2007
    Location
    Philly PA, Wildwood NJ, Indialantic FL
    Posts
    2,382
    +1
    24
    Its either the ring or the rod bearing went and bounced around along with pistion pieces. It most likely ran lean and destroyed the piston which threw the ring pieces around. How many hours are on it? Beat that cylinder with a rubber mallet and get it off to figure out how bad the damage really is.

  4. #4
    silvercrxsir's Avatar
    Join Date
    Sep 2011
    Location
    ocala,fl
    Posts
    334
    +1
    8
    K so I got it all tore down and somehow the ring came out and wedged itself between the piston and cyl and worked its way up into the top and got pounded between the piston and head so now the head piston and cylinder need to be replaced I'm wondering what would cause this to happen the guy I got it from supposedly changed the top end but I have noticed how he seemed to not know what he was doing in a few cases and I'm gonna redo the rear cyl also so I wanna know what to look for in there my biggest concern was that there is a lil bit of metal in the bottom end and I really dread pulling the motor and splitting the cases can I just rinse it out real good with solvent and vaccum it out and oil the bearings there really is very little metal in there and the motor didn't run long at all like this

  5. #5
    silvercrxsir's Avatar
    Join Date
    Sep 2011
    Location
    ocala,fl
    Posts
    334
    +1
    8
    I'm not sure if a lean condition was the cause i run 32:1 yamalube and I just put new plugs in the other day and they are a nice chocolate color the piston didn't break at all the rings somehow came out and got all bent and twisted up in there I dunno how it would go lean all of a sudden it has been running real good ever since I bought it and its a thing that just instantly happened and since its down til spring I will have the carbs cleaned and rebuilt I'm guessing the top end has 15hrs on it the machine has 155hrs on it is it possible that the moron that did the top end did something wrong

  6. #6
    silvercrxsir's Avatar
    Join Date
    Sep 2011
    Location
    ocala,fl
    Posts
    334
    +1
    8
    Is it possible the rings weren't aligned right and somehow they rotated and hit the gap on a port the reason I ask is on the top of each ring groove there is a hole with a pin in it and the both rings are passing over this spot and the pin is fairly deep in the hole the hole isn't in the middle of the groove its on the top edge but the ring passes right over it instead of having the gap meet there

  7. #7

    Join Date
    Jul 2010
    Location
    KC
    Posts
    478
    +1
    1
    This happened to the ski I rebuilt before, the guy didn't know what he is doing and install the piston the wrong way. When the ring pass the exhaust it open up a little and close up again when it pass the exhaust. Each time taking a little part of the sleeve and finally the gap get to big for the ring to get back in possition and bam.... You can check by looking at other cylinder normally if he install one wrong the other will be install wrong too. One more thing is that he might not gap the ring right.......

  8. #8
    silvercrxsir's Avatar
    Join Date
    Sep 2011
    Location
    ocala,fl
    Posts
    334
    +1
    8
    Ya its sec something that was done wrong in the top end the pun that holds the ring in place looks worn and is pushed in I think he didn't gap them right

  9. #9
    post a pic of the piston tops this will tell us if it was lean

  10. #10
    silvercrxsir's Avatar
    Join Date
    Sep 2011
    Location
    ocala,fl
    Posts
    334
    +1
    8
    I wish I could I can't seem to since the only internet access is through phone the cylinder appared to have oil in it it wasn't really dry and the piston top and the head has an oil film on it and looks just like the rear cyl my main ques is do I just go through Sbt for $475 and buy a complete top end with 2 resleeved jugs or do I get another nikasil jug and hone the rear

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. Replies: 12
    Last Post: 10-08-2012, 06:19 PM
  2. so its not bad gas its a little more serious than that
    By silvercrxsir in forum Yamaha PWC Performance (2-stroke)
    Replies: 0
    Last Post: 09-21-2011, 10:36 PM
  3. Could it be bad gas?
    By Davpmars in forum 2-Stroke Performance
    Replies: 4
    Last Post: 07-13-2010, 07:18 PM
  4. Did NOT Winterize, now wont start. Is it Bad Gas? Advice?
    By vjkevlar in forum Yamaha PWC Performance (2-stroke)
    Replies: 11
    Last Post: 04-25-2010, 02:07 AM
  5. So its 55º here
    By Pettee in forum Sea Doo Open Discussion
    Replies: 7
    Last Post: 12-27-2005, 08:49 AM

Posting Permissions

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