Blown SUV 1200 Motor

[byroncfoster]

My Waverunner stalled on me while running full throttle twice. The second time I was able to get it started and running long enough to get me back to the marina and on the trailer.

The local Yamaha mechanic showed me that 2 of the 3 cylinders had really low compression. 80 and less than 25 in the #2 and #3 cylinders. He suspected that the cylinders were etched.

I'm planning to inspect the cylinders and pistons, then will order a top end kit to replace the cylinders and pistons. My question is, do I have to remove the engine to make the change?

When the ski was running, I heard a lot of rattling of the impeller, but it ran fine. Does the rattling indicate worn drive shaft bearings? Can I change those without removing the engine as well?

Thanks for your help!

Chris

[Josey Wales]

Re: Blown SUV 1200 Motor

Sorry to hear you had trouble. You will have to remove the engine its too hard to squeeze the rings and get the pistons back into the cylinders with the engine in the hull. It will be easier to change the driveshaft bearings with the engine out too. Wish you good luck hope you are back on the water soon!

[byroncfoster]

Re: Blown SUV 1200 Motor

Thanks! Not what I was hoping to hear, but glad I know the facts before I start.

[Josey Wales]

Re: Blown SUV 1200 Motor

I know. Wish you were closer would help you get it going. Good luck.

[byroncfoster]

Re: Blown SUV 1200 Motor

I could definitely use the experience! Thanks anyway :)

[torquenut]

Re: Blown SUV 1200 Motor

Rattling at impeller/pump most likely is wear ring has high spot hitting impleller.
Make sure you rebuild the carbs and that each speed screw is adjusted per OEM recomendations.

[byroncfoster]

Re: Blown SUV 1200 Motor

Thanks Torquenut! I'm sitting on the fence considering replacing the engine as opposed to replacing the top end. Will do on the carbs & perhaps changing the pump housing will fix the rattling...

I appreciate the advice!