Rave Valve Melt Down

[GSX RUNNER]

Any ideas on this one?
One of my Rave Valve water regulator pistons completely melted, along with the Rave valve cap after a run yesterday. Had it out longer than I have in the past but it was a beautiful day!

 

[WhiskeyD]

The housing is probably worn out. OSD sells replacements or get a good used one.

 

[mikidymac]

Is it the RAVE valve on the engine or the water valve on the muffler?
Only the ones on the engine are RAVE valves and have nothing to do with water.

 

[etemplet]

If it is melted it got really hot which would make me check the cooling water lines to the exhaust. I'm not sure how hot the water box gets in normal operation but it isn't hot enough to melt things. I'd also check the exhaust hose for internal blistering. Find out what happened. good luck !!

 

[GSX RUNNER]

Is it the RAVE valve on the engine or the water valve on the muffler?
Only the ones on the engine are RAVE valves and have nothing to do with water.

Yes......Rave valve on the engine. The one in the back by the PTO carb.

 

[gp1200x]

Show a picture of it. I have never had a rave valve top melt. I have both 800 XP and 957 XPLs. What year and engine size is currently in your gsx? The two on top of the 957 engine have air lines going to them and there is no water involved with engine rave valve assemblies. Like as mentioned above I don't see how it melted inless there was a lot of heat in that area for some reason which is abnormal. I have never seem it on mine engines over 25 years. As metioned above get it out of the water and start checking water passages for any blockage on the hose in the cylinder area and check exhaust for leaks. It should not be getting that hot in that area to melt things unless something is wrong. Did your craft suddenly lose power at times out in the water or stall?

 

[mikidymac]

Yes it is common for the top of the RAVE piston to melt the threads that go onto the shaft.
The cause it typically the o-ring on the shaft becomes too hard to seal at high RPM and hot exhaust gas melts the plastic.
If a new O-ring doesn't solve the issue then the aluminum housing and or shaft are worn and will have to be replaced. Start with new o-rings.

 

[JJinSC]

Yes it is common for the top of the RAVE piston to melt the threads that go onto the shaft.
The cause it typically the o-ring on the shaft becomes too hard to seal at high RPM and hot exhaust gas melts the plastic.
If a new O-ring doesn't solve the issue then the aluminum housing and or shaft are worn and will have to be replaced. Start with new o-rings.

And replace with OEM. I tried the OSD brand and had a blade crack and fall into the cylinder.

 

[etemplet]

I bought a few aluminum pistons for my stash. Gonna give them a try on my 96 GTX.