Water Valve on 96 GTX

[etemplet]

Reading up on the water valve set up on the GTX. It was loose on the threads and I am trying to figure out how the valve is suppose to work. Looks like I have flow through all three of the bottom holes with the valve removed. Does this valve pull down to close with suction ?? Also looks like I might have an issue on the 97 GTX.
I took a picture of the water valve. I don't want to remove it cuz we are riding this week. Is this what it looks like when the bellows is leaking? This ski is not having RPM issues up high but is sluggish. The other ski I found the valve loose on the bottom threads. That ski is definitely having high RPM issues. 6500 is all I get. Gonna work on this today and see how it goes.

 

[mikidymac]

So, yes from the rust the clamp is bad and there is a good chance the bellows has a hole in it (bad design).
It pushes up from water pressure against the spring and closes off the water flow to the pipe to dry out the exhaust at high rpm and will typically loose 4-500 rpm if it isn't working on top end.

You can pull it up and out but there is a chance it will not reseal and it can leak causing the exhaust to overheat. IF it is already leaking water out when running you have nothing to loose.

As a temporary fix you can sometimes RTV the hole for a few days but if when you put it back together if it pulls our really easy chances the housing is bad and they can't be fixed the entire thing has to be replaced. When going back together push it back in really hard and gently pull to see if it stays.

 

[etemplet]

Thank Miki.... I'm leaving the valve with the rusty internals alone. That ski is bumping 7K on the tach. I will get new parts for both valves. Who knows, I might have some of these at home. The ski with the RPM loss has good looking valve internals but the housing was loose, so I gave that a quick fix. Hopefully something I did today will make a difference.

 

[etemplet]

Okie Dokie, I pulled the water valve on the GTX that I figured was leaking. I also ordered a new bellows. Looks like the bottom clamp for the bellows rusted off completely.


The second picture is a valve I pulled off a 1996 XP. The clamp is in place but is rusting badly. I was going to replace the whole unit and I may. but.... where can I find the clamps I need?? They are awfully proud of those things. Has anyone improvised a bottom retainer?

This picture is the GTX as it was in operation. The bottom clamp is gone.



This is the 1996 XP. As you can see it is rusting also but the clamps are in place.

 

[etemplet]

I'm just wondering what performance impact this would have on the ski. The ski pulls very well from 6k to 7k. I have trouble with it pulling really hard from the first application of wide open throttle. Has a flat spot around 4-5K.

 

[mikidymac]

They just dry out the exhaust at 6500-7000 rpm. If they fail you loose 500 rpm on top end. The blames are available from seadoo, $22 for the top one and $5 for the bottom. I use a couple wraps of stainless safety wire.

 

[etemplet]

I thought of doing that on the bottom. I think I can save the one on top.

 

[etemplet]

I took the valve apart and tried to figure out exactly how it works. Kinda strange. I lapped the seating surface of the valve shaft, replaced and sealed the bellows. I did a few tests but still don't get how it works. Looks like pump[water pressure flows in and when the pressure get high it closes the valve which shuts down pump flow to the muffler. Then the muffler pressure pushes the water in the pipe out of that same valve through a lower port and into the water system in the pipe near the heads. I'm not sure I have this correct, just trying to figure out how so I will better understand troubleshooting this in the future.

 

[mikidymac]

The water pressure from the pump overcomes the spring pressure and pushes the tapered pin up sealing on the stainless washer and reducing water into the pipe drying it out at high rpm.

 

[etemplet]

So when the valve closes, water to the exhaust pipe and muffler are reduced.

 

[mikidymac]

Yes, this dries out the inner exhaust making the engine think it has a bigger pipe which helps top end. The manual actually has a very good description of how the system works.

 

[etemplet]

I checked the water valve on the GTX that, according to the tach, is only turning 6530RPM. I didn't physically see any issues so I am going to leave that one alone for now.

I will be reading up on this in the manual. Thanks for the reference.

 

[etemplet]

I didn't get a chance to ride my wife's ski but that was the one with the leaking water valve. I didn't think it would matter much as her ski is faster... but it made a difference. She picked up about 2-3mph on the speedo. I'm sneaking up on performance increases.