Rave valves 96 xp 800

[Angelse68cal]

Was wondering if anyone knows what went wrong or if there is anything wrong with the Rave valves on my seadoo 800 motor. Long Story Short... I had them rebuilt with new O rings and gaskets but there was no zip tye on the bottom of the bellows. I wanted to know what would cause quite a bit of black substance to come out the Rave valves and also Melt the crap out of the plastic piece on the one one the from cylinder. Anyone have any knowledge on this?

[julrich]

Re: Rave valves 96 xp 800

Ya im haveing the same problem.

[mully]

Re: Rave valves 96 xp 800

My rave valve melted too. I had rebuilt them however I did not use a zip tie on the bottom bellows. I also goofed by placing the o ring on top of the housing not under the housing. I have had a rave valve melt after the shaft broke. I then had one break at the casting of the numbers. That broken one fell into the cylinder and hit the piston. Had to open the top up. Whatever is going on in yours becareful it can trash a good engine/piston/cylinder.

[julrich]

Re: Rave valves 96 xp 800

My o ring was so hard it was like a hard plastic ? had to have been from the heat

[ncdoo]

Re: Rave valves 96 xp 800

Are the o-rings suppose to be a bit larger than the rave valve stem? The one I got were? Didnt make much since but I installed them anyway. I thought they should have fit tightly around the stem to do any sealing at all?

[Technical Support]

Re: Rave valves 96 xp 800

The blow by is usually from an improperly installed top spring, or it needs to be cut back a little to be tighter. The o-rings are for a bump-stop .

[julrich]

Re: Rave valves 96 xp 800

What about wire ? or a zip tie I have seen guys use that instead of the spring. Also are you saying the blow BY {HOT OIL} is melting the plastic cap ?

[Bill O'Neal2]

Re: Rave valves 96 xp 800

The correct rave valve stem orings fit snuggly on the shafts. That is part of your problem. Then not only work as a bump stop, but they help seal the shaft from exhaust gases.

The trick to tightening the spring around the bellows top is to unwind it where it meets together and snip off 1/4 inch from the female side and then screw it back together. This is only needed if the bellows comes off by itself.

A good bellows rarely needs any clamp at the bottom. Old worn out and soft bellows do need a clamp at the base to keep them attached. SD acutally did use a smaller spring retainer on some models.

If a clyinder runs too lean, the rave valve temps can go way up. The heat transfers up the shaft to the plastic piston ( the round thing that the bellows attaches to). If too hot, they melt.

If the slot in the clyinder gets worn until it is too sloppy, heat and exhaust pressure will travel up the slot along side of the rave valve and push the bellows off.

If the clyinder runs too rich, it will push alot of black oily liquid up into the bellows. Over time, it will soften the bellows and may even push the bellows off the rave valve piston. The black residue will run down the side of the clyinder.

Most of this is caused by a lack of proper maintence to the rave valves and/or the carbureators.