2002 Virage TX melted down piston... any help is appreciated.

[barto]

So, got my jetski back from a friend (I'm sure he'll chime in some time on here). He called and told me that they were riding for a few hours and all of a sudden the ski just went from WOT of around 62 to no more than 40. He brought it back to shore and checked the plugs. They were completely carboned up and the middle one looked a little different. He tried new plugs, and still not running right, so he threw it on the trailer.

I got it home today and compression checked the engine 120 on the front, 120 on the back and 0 on the middle. I figured a piston was the culprit. Here are the pics.



So, before I start to buy things and get this bad boy back up and running, do I need to be concerned with the bottom end? seems like a giant hole to just ignore the bottom end. Also, the cylinder seems to be quite scored.

If I've got to go new cylinder, do I have to go all three? where do I get a new head? I assume that the middle one is fubar.

I've been googling, browsing the forums, and looking at the google docs site that K44 has, so I know enough to ask...

Thanks guys!

[barto]

Should also state that I need to find out what caused this grenade to go off. Not sure. Its only got 40 hours on it or so. Bought it as a "barn" find from a co-worker who only put 11 hours on it from 2005-2011. Likely that it was ridden once a year then winterized. Never fogged after riding and let sit for months.

I replaced all tempo lines, friend cleaned carbs last year, replaced start/stop relay. Fogged each winter, stored in garage. Never any issues except this.

[Mr. GP1800]

As bad as that center cylinder looks I would be pulling the motor and tearing it down to inspect the crank as well.

[barto]

As bad as it looks its worse in person =). I'm going to be tearing it down. It seems like I've got room in the hull of this Virage TX to actually tear it down without pulling the whole motor. I just pulled one on my buddy's and it wasn't bad, but his is an SLX with zero room for anything.

[barto]

So no I am starting a check list. I will then create a shopping list from that. So far I know I will need to sleeve or buy a new cylinder. You'll have to excuse my ignorance of the terms to use, as I am not use to working on 2 strokes. Rebuilt many 4 stroke motors (chevy and ford, one dodge).

So far I need.
-Inspect all pistons
-Inspect all sleeves
-Inspect head
-Inspect crank
-Inspect crank seals
-Inspect connecting rods

What am I missing?

[Mr. GP1800]

You can't split the cases and check the crank without pulling the motor.

Just pull it out and get it on a bench. Its so much easier that way.

I could have the motor out of that ski in an hour as long as things arent all corroded.

[barto]

Things aren't all that corroded. I'll be pulling it out when I can. I just pulled one out of an SLX, which was much more difficult because of the small hull. I've got a good range of impact tools to make the work quick. I'm guessing from the lack of damage on the other cylinders the culprit is the middle carb. I'll be guying a rebuild kit to make sure I get that all fixed up.

[barto]

Should I be looking at one new jug/piston or should I be replacing all three? compression is 124 in each of the "good" cylinders. Also, go new for the jug or just buy a sleeve for the current one?

[Mr. GP1800]

If it were me, I would probably just do a full rebuild on that motor. Crank, 3 cylinders bored and new pistons. All new seals and gaskets. If you wanted to, you could probably get away with one cylinder, but I would just do all 3. At that point you are only a few hundred bucks into it more to do all 3. I bet the crank needs work too.

[def]

i just pulled a center piston out of my 96 slt780. was a bitch but i left it in the hull so i could practice my swearing. The skirt of the piston was shattered on both sides, top ring welded in place, second ring sorta moves. lol. Missing cap nut on top of head was the culprit...
I know it would be against all advise, but heres the procedure i went with.

flush the hell outta the center jug case with gas
used shop towels cut into strips and folded, then pressed in with the crank
rotate crank until knuckles bleed appropriately, changing out the shop towel until no fragments show
flush with gas again and repeat
replaced center jug/piston with parts from parts machine
pratice swearing some more, shoot a clipring under the motor (of course)
wrap large magnent in shop towel and go clipring fishing
actually found my clipring and another from someone elses previous fury
get bottom end together and exhaust bolted in (PTO didnt want to line up with exhaust)
cheer and run home at 130 hoping wife hasnt woken up yet (she loves my personal entertainments)

Im hoping to run it this weekend unless work delays my final assembly.
I will let you know after the weekend if i would just advise rebuild! hahaha