[SuperSport346]

I'm not actually sure the cylinder is #1, but it is the one nearest to the front of the ski.

What happened was some friends were out riding when the motor completely died on them. Tried restarting it a couple times, with no luck. I did a compression test, and the other 2 cylinders are around 110psi, while cylinder #1 is around 25psi.

I pulled the head off today. I have pictures attached. The piston was obviously hitting the head. Also, that cylinder is dry, whereas the other two had some oil/gas on the cylinder and piston. The other thing is that piston has a little bit of play in it, whereas the other two do not.

I just recently installed WaveEater clips, so I know it's not the pv. I'm almost thinking an oil line got pinched and because of that I damaged a connecting rod or something. There isn't any oil in the hull, so if I wasn't getting oil it's because a line got pinched.

I'm planning on pulling the cylinder off tomorrow and seeing what damage I find underneath that piston. Any ideas in the meantime?

Also,
-From this point, what parts should I plan on buying? Will I need a new piston or head? I've noticed that spark plug doesn't screw in like it used to. I wonder if I warped the head...
-Can I reuse the gaskets? I have some Permatex Copper Gasket spray I used installing my d-plate. Can I just use that?
-Should anything else be done while I've got this torn apart? I'd really like to get it running asap while it's still warm out.

 

[Ernest T]

1. You could have more damage in the bottom end (crank shaft/bearings, connecting rod, etc.). You'll have to tear it apart more. You will need to take apart the lower end anyhow to look for metal pieces.
2. I agree the head is probably warped.
3. Don't reuse the gaskets.
4. Go premix.

 

[SuperSport346]

1. You could have more damage in the bottom end (crank shaft/bearings, connecting rod, etc.). You'll have to tear it apart more. You will need to take apart the lower end anyhow to look for metal pieces.
2. I agree the head is probably warped.
3. Don't reuse the gaskets.
4. Go premix.

From what I'm hearing, you're right. I'll need to at least inspect my crank, if not buy new. I'm betting the head is warped as well. Would that have to be replaced, or is there anyway I could use it warped? I'm also thinking I'll need a new piston as well.

I also have an oil block off kit sitting here that I've been meaning to install...

 

[SuperSport346]

Took the sleeve off today. There are pieces of metal all over, so I will have to tear it apart and clean it out. The problem is that where the connecting rod wraps around the crank, has significant play in it. It also looks like the bearings and other parts around the crank next to the rod have worn away (the metal pieces).

I'm guessing these parts cannot be bought individually, and I will need a new crank? Any suggestions on which crank to buy? I found them ranging from $475 to $1000 or more.

I also need a new head, so I'm thinking the kit Riva sells for like $390. Add a used OEM piston, and I'm still looking at close to a grand in parts...

Pics from today:

 

[Ernest T]

Yea your getting to a $$ point, where a new engine might be a consideration. Yea, no good way to fixed a warped head. Don't know what crank to recommend.

 

[SuperSport346]

What do you think of this: yamaha wave runer 2002 xlt 1200cc?

I emailed the seller with a few questions. Out of the ski, I'm sure there's no way to start it up. I could pull the head off and see what it looks like in there.

I figure if I can get him to $500, it would be worth that in parts even if it doesn't run. I could then keep my old motor for spare parts, or sell them.

 

[Outlaw]

Did you inspect the cylinder to see if it was scored? If it is try honing the jug. We use to cut our heads to lower the dome for more compression/ performance on snowmobiles. if you mill it like ten thousandths you can always raise the dome with an extra gasket. Just a thought.