1999 GTX RFI No compression rear cylinder

[ssteig]

Ski was running good. would go about 53 mph. suddenly it had a hard time starting. It fouled 3 sets of plugs in 3 weeks when the previous set lasted a year without any problme. Sometimes when it did start it would seem to cut one cylinder out after it got heated up and have 1/2 the power and would not idle. This continued for a weekend until the cutting out on one cylinder was constant. I thought coil went bad but, to my surprise and dismay, the rear cylinder had no compression. Took off head and rear cyliner does have a few marks like something metal (possibly a ring) got between the piston and head. I can not find any cracks in the cylinder, piston or head.
Can the rings be that bad to have 0 psi? Suggestions? Mechanic wants to put a new engine in it. I think it would be cheaper to rebuild what I have. I am very good on cars and motorcycles. This is my first seedoo.

 

[seadoosnipe]

Compression!

I just looked up your engine and see that you have the Rotax engine. These are awesome and durable engines. If you have 0 psi on your compression there could be several things that went bad. Anything from a shattered rave valve, or the gear on your rotary. I have a 1997 and had to search for a place to get parts, because like you, I'm pretty good when it comes to my mechanical apptitude. There a really simple engine. If you know what cylinder it is, then I'd say pull it to find where the metal part came from. If in fact it was a ring that seperated and did the damage to the cylinder and piston only, then you can go to sbtontheweb.com and do a model search on your engine. They have a total rebuild for your top end priced at $430, comes complete with pistons and jugs and everything else you'll need to rebuild the top end. If you prefer not to risk rebuild, measuring for exact tolerances, etc....you can just replace your engine with their premium engine replacement for $1149.00, that comes with a 2 year guarantee!.........I get all my parts at this place. Impellors at $25.........almost anything you purchase from them requires you to send in your core. When you order, they send it in the box that you'll turn around and put your core in, take off their sticker and put the one that comes in the box back on it and send it out by FedEx..........can't get any easier than that. I LOVE THE PLACE!.........Do a little research at this place, you'll be amazed what they have to offer!...........shouldn't be long and you'll be back to, HAPPY SKING!.................hope I've helped!....BTW, you posted in the sport boat category...LOL