1997 GTX RAVE valve keeps melting

[alexpatnode]

If it's RFI, then no. I don't think they made any carb model 787s in 2001, did they? If so, it may be good, but I'd still replace the bellows and O-ring as they're like 17yo now.

I ended up finding one from a 1997 GTX with the same motor just to be safe! I have new o-rings and such that I'll be sure to put on. Thanks for the help!

 

[etemplet]

I am going to take some measurements on my rave valve stem and guide clearance. They are pretty loose but nothing is melting yet. I am looking for numbers to compare. I'm pretty sure looking at mine... they are out of spec.

 

[GGuillot]

Since I own two carb skis with the 787, I'm wondering if a machine shop could drop in valve guides on the worn housings of these 787 RAVE valves? Seems to be a way to prevent tossing the housings in the trash and buying questionable used ones.

 

[etemplet]

Since I own two carb skis with the 787, I'm wondering if a machine shop could drop in valve guides on the worn housings of these 787 RAVE valves? Seems to be a way to prevent tossing the housings in the trash and buying questionable used ones.

If have (2) 787's as well.... and I plan on doing exactly that next week. I am trying to get the proper clearance numbers. I imagine .005" would work. I have not been able to find any official numbers for min/max on the stem clearance. It is most definitely not cost effective for a machine shop.

If anyone can take a measurement on the valve stem and post I would be interested.

Save your old $hit I may be feeling generous. LOL

 

[etemplet]

What about this clamp SeaDoo is so proud of?? RIVALAIR CLAMP Part No. (293650065) I think I have the correct number. It clamps the large diameter of the Diaphragm to the piston. The price is absolutely ridiculous.

 

[mikidymac]

That is the number for the clamp that holds the bellows to the cap on the Muffler valve. I see it listed as $21.64 not $65.

 

[etemplet]

Lotta money for a little piece of crap clamp..

 

[Sportster-2001-951C-Stock]

If it's RFI, then no. I don't think they made any carb model 787s in 2001, did they? If so, it may be good, but I'd still replace the bellows and O-ring as they're like 17yo now.

Correct, the 2001 787 was RFI

 

[Sportster-2001-951C-Stock]

Was looking on eBay for the parts and saw that I can buy pre-owned valves fully assembled. I know that there is a risk for buying used parts and I found one that had 16 hours on it but is from a 2001. Does anyone know if this will work for my 1997?

Used parts can be rebushed if you're so inclined and can do a good job. I think I read someone did that on theirs? Anyway, too much exhaust blowby past the valve shaft seal will definitely melt the bellows and cap, which to me means the valve might not be fully opening? I think some aftermarket bellows are too stiff and don't stretch enough, causing the valve not to reach full open position?

 

[etemplet]

Used parts can be rebushed if you're so inclined and can do a good job. I think I read someone did that on theirs? Anyway, too much exhaust blowby past the valve shaft seal will definitely melt the bellows and cap, which to me means the valve might not be fully opening? I think some aftermarket bellows are too stiff and don't stretch enough, causing the valve not to reach full open position?

Interesting observation on the stiffness of the bellows.

I plan to bush my rave valves next week.... all 4 of them.

 

[PWCCNC]

I am in the process of making aluminum Rave valve caps/pistons if anyone is interested in pre ordering some? CNC machined from 6061 Aluminum for the 787 motors. And will be anodized red or blue for corrosion protection. 29$ per cap or 2 for 50$ You can email me 651steve651@gmail.com.

 

[mikidymac]

That’s a great price but will not fix the problem of worn housings and valves.

 

[etemplet]

I am in the process of making aluminum Rave valve caps/pistons if anyone is interested in pre ordering some? CNC machined from 6061 Aluminum for the 787 motors. And will be anodized red or blue for corrosion protection. 29$ per cap or 2 for 50$ You can email me 651steve651@gmail.com.

Heck of a price man !! Thanks for making things more affordable for everyone. Bushing rave valve housings would be cool but there isn't much money there to be made.

 

[PWCCNC]

A worn housing may still need to be replaced, but this should be the last cap you have to buy.

 

[etemplet]

Go for the BLING !!

 

[etemplet]

I ordered new rave valve housings for the GTX and installed them today. I took measurements on the housings I removed. What was fortuitous was that I had one valve leaking more than the other so I got some good information. New Housing guide bore measures .300" The shafts, mine are worn but I got a good size, measure .291". That means that the new stuff has roughly .010" clearance.

Now then, on the valve that had minor leakage from the piston area, the engine was pretty clean under the valve. The bore on that housing measured .308"to .310". I'd say these housings need replacing at .306"

On the Mag cylinder the valve was leaking oil on the engine and collecting in low areas after only a couple hours of running time... the bore size on the housing is .315" to .318". I can only surmise that an unmetered volume of gas is allowed to enter the valve bellows chamber and may cause the valve to lift prematurely, stunting acceleration. After all, there is a small hole for that purpose designed into the valve body.

I cleaned up the valves, did a bit of polishing on the stems and did the install. I wonder if I'll notice anything other than less leakage from the valve. I do enjoy the chase.

 

[etemplet]

I ordered new bases for the other GTX today. Gonna change both sets now. I have a valve leaking oil on that ski as well.

 

[etemplet]

Question.... Do rave valves chatter? When I removed bellows from one of my valves it was worn on the inside, down at the bottom near where the valve stem enters the housing. I am trying to figure out how it got so worn in just a few hours of operation. I replaced the bellows on both skis and only rode them this summer. So far I've only seen this on one bellows. I was wondering if I could have done this during assembly. I don't see how this could wear that way during normal operation. I don't think I have 10 hours on the ski this year. Thoughts?

 

[PWCCNC]

You could have a burr on the edge of the housing, and I assume you have the springs installed on top of the Rave piston?

 

[PWCCNC]

I’m working on billet housings that are higher quality than oem, possibly a ware resistant bushing where the valve rides.
The aluminum Rave pistons that I am manufacturing are on eBay already and they came out great!

 

[etemplet]

You could have a burr on the edge of the housing, and I assume you have the springs installed on top of the Rave piston?

This is a 1/8" wide mark completely around the inside lower area of the diaphragm. Yes everything installed correctly.