Errr Yam... 99 GP 760

[Wetbehindears]

Hey Everyone,
Working on a 99 Yam GP760. My first ski to work on, just FYI. Getting a small stream of water out the exhaust and white smoke with running on the flush kit. I had already done a new piston/ring job on the ski and have a new gasket on top of the head. I have pulled the plugs and with the water on, I dont see any water entering in from the water jacket. Im suspecting that "maybe" im getting this from the exhaust manifold gasket? If that seems reasonable, would it create white smoke and affect the idle? Im just looking for advise before I tear into this again.
The ski will run, but shoots steady stream of water from the exhaust, and blows white smoke then throttling. I do not suspect the water is entering in from the water jacket on top of the pistons however!
THANKS!!!!
Hey if theres any hardcore jet ski builders in here, please let me know. I want to bore this ski out to the next size piston and rings, and just want some advice and have some questions!

 

[Jeff Walkowiak]

Re: Errr Yam... 99 GP 760

you can't run the water with the engine off you are filling the crank case with water.

 

[JUSTINTIME]

Re: Errr Yam... 99 GP 760

do a leak doen pressure test
u will see where the water is coming in

 

[Wetbehindears]

Re: Errr Yam... 99 GP 760

Hey guys,

Okay, you will have to explain this one a little harder. If you run the flush kit with the engine off, you will get water in the crankcase? If so, from where? Backfeed off the exhaust?
If im running the jetski on the ears, WITH starting the jetski first, should I see a small stream coming out of the exhaust? Right now, Im assuming that I should have NO water coming out the exhaust at anytime? I have replaced the upper cylinder (piston cover) gasket, and have replaced the exhaust side gasket where the exhaust enters out of the side of the cylinders. Im trying to find how water enters the exhaust, but I really dont know if its suppose to or not?

 

[Jeff Walkowiak]

Re: Errr Yam... 99 GP 760

without going in to a lot of detail, do not ever run the water if the engine is not running, never///// if you do you will find out why .as for water from the exhaust with no water conected that is normal the water box holds water.

 

[Wetbehindears]

Re: Errr Yam... 99 GP 760

I little more explained answer? why, because good chances it may have already happened!
1. Is water suppose to come out of the exhaust while running on the flush kit?
2. If this has been done what am I looking for that has happened?

Sorry, having a bad night here!