Thread: Bad pistons, what happend?
03-13-2007, 06:03 PM #1
Bad pistons, what happend?
Take a look at these pics. Can you guess what happened. These are the ones form my Doo, 20 hours after rebuild. Keep in mind this has lots of goodies. 44 MM carbs, R&D intake plate & mandifolds, R&D exhaust manifold, factory pipe, high compression head, OP intake grate, OP ride plate, OP nozzle, and lots more.
03-13-2007, 07:04 PM #2
03-13-2007, 07:48 PM #3
It looks like the ring locator pin has risen to the top. Or a butterfly screw!!
03-13-2007, 07:50 PM #4
That is the pin for the ring. The piston has burned away. This is also a SBT pistons. Both pistons are showing the same "wear".
03-13-2007, 07:51 PM #5
looks like it went lean and the piston started melting at the exh. port. at least as far as I can tell.
03-13-2007, 07:54 PM #6
- Join Date
- Aug 2006
03-13-2007, 07:55 PM #7
The one on the right that is a possibilty. The arrows point to the exhaust. There is some nice signs of piston wash on the pistons, hard to tell from the pics. Keep in mind that sea doo's have a rotery valve, insted of reed valves. Maybe the timing is off? I am not sure what happened. I am not sure what to do to correct this problem, other than go with a set of non SBT pistons.
03-13-2007, 07:59 PM #8
03-13-2007, 08:04 PM #9
What do you think about this....
High compression domes. Increassed heat, the ring/ piston crown on the SBT's are not able to handle the extra stress. I say this because I have done several plug chops, and have always seen a good rich plug reeding.
03-13-2007, 08:25 PM #10
I see very little wash on those pistons. Doesn't sbt warranty their pistons? maybe you could get some freebies?
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