Rotary Valve Question - 1996 Sea Doo GTI

[PWC4ME]

Our 1996 GTi quit about a week ago. It has spark, gets fuel, air, etc.. Thought it may be a carb problem and when we got down below the spark arrestor one of the screws that holds the breather box was missing. Once the carbs were removed the screw was found in the intake manifold by the rotary valve. Upon removal of the intake and rotary valve cover we found the screw stopped the rotary valve from spinning. It is my understanding the rotary valve shart turns from the middle of the crank. In looking at a parts book I see there is a spring on the far side of the shaft as well. Can the shaft spin intermittently? Ours does. If it is supposed to do this, what would make it have proper port timing? If it is supposed to turn full time, what would make it sometimes turn and not other times?

Any thoughts or suggestions are appreciated!

Thanks!!

[dsolie]

Re: Rotary Valve Question - 1996 Sea Doo GTI

It's a 1:1 drive, so YES it is supposed to turn full time. If it is not, then that little screw that dropped down caused your brass rotary drive gear to strip... Which unfortunately means a new crank and a new RV gear, Rotary valve and gasket set.

[easttenneski]

Re: Rotary Valve Question - 1996 Sea Doo GTI

yeah its just catching whats left of some of the teeth and grabbing occasionally, been down this road before, shaft with gear is about 89 bux

[PWC4ME]

Re: Rotary Valve Question - 1996 Sea Doo GTI

Thank you east tenn. So you don't think that the crank is damaged? There is a big difference between just the shaft and replacing the shaft and crank.

[dsolie]

Re: Rotary Valve Question - 1996 Sea Doo GTI

There have been stories, few and far between of people being able to save the brass gear on the crank with a file... But in all my motors, that has never been an option. You are going to have to take it all apart regardless, inspect and report from there.

[easttenneski]

Re: Rotary Valve Question - 1996 Sea Doo GTI

I doubt you would have to replace the crank, but it has to come apart to see, the brass gets galded to the gear sometimes and gleaning it off with a pick and some very light sandpaper usually works.

[PWC4ME]

Re: Rotary Valve Question - 1996 Sea Doo GTI

Thanks for the input guys. Will probably be pulling the motor this afternoon. I worked on 2-cycle dirt bikes in the past and they were pretty simple. The rotary valve and 2 cylinder are new twists to me. I realized either way the cases would need to be split because shavings.

In the parts diagram there is a spring on the far side of the worm gear on the rotary valve shaft. What purpose does that serve?