Boring out a 717/720. What are the specs?

[Daveegt]

I got to the point of tearing down the engine on my 2001 Seadoo GTI. It got water into the engine by a friend when the rear exhaust hose came off flooding the engine compartment and getting into the engine. Not knowing, he ran it. It broke a ring and needs to be bored out. What are the specs for boring it out? I have found kits for .25, .5, and 1. Mm oversize Pistons. What spec. Is needed for the boring of the cylinder? I'm not sure how far it will need to go.

 

[howie099]

Most people send out to get bored and honed so the machinist picks out piston size as need be so you usually get the pistons from the shop. You can look and judge for yourself most only need 1 size over unless the grooves are deep.They always try to do the smallest size so they don't have to re-sleeve the engine. You need to send the pistons with the cylinders to the shop also so there sized right.

 

[Daveegt]

I assume you are saying the old piston should be sent to the shop?

 

[howie099]

The new ones you send it.

 

[mowertech]

Need to measure the cylinder first to see if it can be oversized

 

[racerxxx]

Clean the crown of the piston with lacquer thinner or something, nothing abrasive. There should be numbers on there. You can determine if it already has a bore job on it and then go from there.

 

[racerxxx]

A n image of the stampings on the crowns

 

[mowertech]

The specs will be in the manual.

 

[racerxxx]

Yes, specs are in the manual for oem pistons. If you use aftermarket pistons use their specs for wall clearance.

 

[Daveegt]

I am having trouble finding a shop to bore out my cylinders? I am close to the Dallas, Texas area. Does anyone know of a shop that can do the boring?

 

[Daveegt]

Ok, after I get the parts to put it back together, what do I torque the cylinder and head to? What type of thread lock should I use?