Top End Rebuild

Faerbairn

Petty Officer 2nd Class
Joined
Oct 3, 2007
Messages
121
Hi,

I recently picked up a 1994 Ski Doo Bombardier GTX Jet Ski 600cc
Motor # 4215879

It looks like the previous owner thought it needed a top end rebuild. The rings are toast. The cam turns nice & smooth. The head is off, pistons removed, cylinders are off and I can see the cam. There is a little scoring on the piston sides and slight hammering on the top of the pistons. The cylinder walls look good and can easily be honed to a nice glaze.

Do we need to go to the next bore size or just replace the rings?

Where I can I purchase an engine manual specific to this exact motor and a top end rebuild kit?

Should I look at or replace anything else while it is apart?

Thank you for your help.
 

veestyle

Cadet
Joined
Apr 10, 2010
Messages
8
Re: Top End Rebuild

there's no cam, they made a 580, 657, and 717. some people referred to the 657 as a 650 and the 717 as a 720. I would bore the cylinders to get the oval out of them, i'd also replace the crank seals on a unit that old as well as inspect the crankshaft main bearings.

best of luck.
 

Faerbairn

Petty Officer 2nd Class
Joined
Oct 3, 2007
Messages
121
Re: Top End Rebuild

Thank you for the tips.

Sorry, the crankshaft is in good shape. It is likely the 580cc.

Where I can I purchase an engine manual specific to this exact motor and a top end rebuild kit?
 

DoGood

Seaman Apprentice
Joined
Apr 16, 2010
Messages
46
Re: Top End Rebuild

www.sbtontheweb.com is one place you could get parts, or have them rebuild your engine. I'm not sure about the manual, if no one is able to help you here try www.pwctoday.com There are a lot more people checking the forums for jetski stuff over there.
 
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