1998 Seadoo Speedster twin 787's complete melt down of rave valve

[angelicious_one]

I keep melting rave valves, and caps. I have replaced everything, all new valves, caps, o rings, housing and gaskets , and they still keep melting. This problem is driving me crazy, I can't seem to figure it out. Any ideas??

 

[Dr Honda]

The only reason they melt, is because they get a flow of hot exhaust gasses. Generally, it's coming up the stem.

Take it all apart, and look for proper fit, and proper sized O-rings, especially if you used aftermarket parts.

 

[angelicious_one]

I used all original parts, it seems the temperature on the valve is getting very hot. So hot it melts them in 4 or 5 minutes.

 

[Sportster-2001-951C-Stock]

I'm convinced they aren't assembled correctly or the housing bore is badly worn and sloppy.

Were the results of the bellows pressure check acceptable or were they leaking? If the o-ring seals in the housing around the valve shaft aren't in the proper sequence, or wrong size, hot exhaust will leak upward into the housing and melt every piece of rubber and plastic in the vicinity. Same thing can happen if the housing bore is worn badly enough.