Hi,

Pull out your spark plugs and tell me what the ends of them look like,

Brown, Gray, Black??

Remeber which cylinder each plug came out of.

Can you remove the tether cord and reach down behind the engine and try to spin it by hand?

I just want to make sure you don't have a seized cylinder.

That's ok

The tether cord is the cord that you wrap around your wrist and plug into the handle bar.

It's the kill switch of sorts if you fall off the ski.

That's just a precaution .. I don't want the engine to magically fire while your hand is down in there.

Now on the back side of the engine. (towards the back of the ski), There should be a black plastic cover that goes over the drive shaft .

Probably has a hose clamp holding it tight.

You'll want to remove that so you can see the drive shaft.

It's just a straigh shaft out of the back of the engine and goes out through the bottom of the ski.

You should be able to grab ahold of it and spin the engine over with the spark plugs out.

ok so the back piston doesn't move.

You're doing fine... Just don't turn it over anymore.

Disconnect and remove the battery from the ski.

Then you'll need to remove the 3 bolts that bolt the exhaust manifold to that cylinder.

and the 4 bolts that hold that cylinder down to the block.

This will allow you to remove that cylinder.

Since the pison doesnt move you either have a broken rod, or piston.

By removing the cylinder we'll find out which it is.