I mentioned I picked up two jet skis at the end of the summer. One is a 2000 Yamaha GP1200R.It was in pretty bad shape but I enjoyed it the rest of the season and expected to do a tear down over the winter. On my last run before calling it too cold to ride, the motor gave out. I went back and forth if I should rebuild or sell for parts. I got it dirt cheap and decided if I built it back after tearing it down, it could be a ski to pass around, ride hard, and put away wet. Here's the rebuild.
Damage:
Third cylinder lost oil either due to a failed check valve or a poorly calibrated oil pump, maybe both.
Every nut and bolt from the ski is set out in boxes and bags in my garage
Empty hull. I redid all the fuel and oil lines too so tanks are out. At this point, worst case, I'm left with an uncomfortable canoe.
Thrown rod from seized piston. Picked up a quality used crank from a shop
Don't think that hole is repairable
Picked up a good used crankcase from a guy in Ct.
Damaged cylinder and piston. Luckily this engine is designed with three separate jugs. Picked up a re manufactured cylinder and new prox piston.
I added an electric bilge pump for insurance.
And finally, the seat is pretty nasty, so we'll take care of that too.
Engine rebuilt ready to go back. It has 3 carbs so those got rebuilt too.
Engine back in. Chokes removed, all new lines installed.
Buttoned up with a new seat. Purrs like a kitten ready for a lake test. Will need carb fine tuning at the lake