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View Full Version : How to service Rave Valve---Pictorial---



Rampage
11-23-10, 06:25 PM
OK I know there is a million threads on how to do this...but I was bored. I see alto of people still nervous on servicing these even after reading on how to do them. (even I was)....but after I did them, I thought to myself that was way easier then I thought it would be....So I thought I would put up some pics on how to do them so people can see just how easy it is.
This is pretty messy so I would def recommend using some latex gloves....took me forever to get it off my hands. I'm sure there is several ways to do this, but this is how I did it. If I missed something please chime in


Start by removing the clip that holds on the cap

http://i100.photobucket.com/albums/m23/proquad81/jet%20ski/102_1677.jpg
http://i100.photobucket.com/albums/m23/proquad81/jet%20ski/102_1678.jpg

Pull the cap off but be sure not to loose the spring under it

http://i100.photobucket.com/albums/m23/proquad81/jet%20ski/102_1679.jpg

Now unscrew the piece under the cap...you may need a 10mm socket to loosen it

http://i100.photobucket.com/albums/m23/proquad81/jet%20ski/102_1680.jpg

Now take a #5 hex to take the 2 screws out

http://i100.photobucket.com/albums/m23/proquad81/jet%20ski/102_1681.jpg

Remove the base....if the whole valve comes out with it just pull them apart after you get it out

http://i100.photobucket.com/albums/m23/proquad81/jet%20ski/102_1683.jpg

Now slide the valve out

http://i100.photobucket.com/albums/m23/proquad81/jet%20ski/102_1684.jpg
http://i100.photobucket.com/albums/m23/proquad81/jet%20ski/102_1685.jpg

Now clean the valve with a wire wheel...and I used some brake clean too

http://i100.photobucket.com/albums/m23/proquad81/jet%20ski/102_1686.jpg

Should look about like this when done

http://i100.photobucket.com/albums/m23/proquad81/jet%20ski/102_1688.jpg

I put a new gasket on as well

http://i100.photobucket.com/albums/m23/proquad81/jet%20ski/102_1689.jpg

Now just reinstall everything and your done

http://i100.photobucket.com/albums/m23/proquad81/jet%20ski/102_1693.jpg

djredman99
11-23-10, 09:45 PM
Good job....pics make instructions much better :)

Rampage
11-24-10, 07:49 AM
Yeah its not really the best write up but I hope it will help someone....On a side note, it's very very important to put the Valve back in facing the right direction....mine is stamped TOP on one side, and that it the side that should be facing the pistons.

RFoster130
11-24-10, 05:01 PM
Nice write up. Thanks for the pics!!! :cheers:

FritoB
11-25-10, 07:38 AM
Nice pictures. I cleaned mine this summer and it is easy. Since I don't have a grinder, I used a stainless steel kitchen scrubber (not steel wool) that was effective in removing the build up. While it's apart, check the small o-ring and replace them if they are brittle.

rau_d1
04-28-11, 08:56 PM
Hey Rampage, I did mine a few days ago after 4 years of neglect, I change O'rings and gasket and a good clean, how often do you recommend cleaning. Also, they were black as yours and had some oil on them, is the oil normal?
Thanks :thumbsup:

Rampage
04-29-11, 01:10 PM
I do mine every couple of months..might be to much but I am really anal about the up keep on my ski. Yeah being oily and black is normal from what I've seen.

dooser
04-29-11, 01:22 PM
Quick question. Other than regular maintenance why do they need to be cleaned? When they are dirty will the engine run poor? Also, (this might be a dumb question) what do the rave valves even do? Thanks

rau_d1
04-30-11, 08:07 PM
Rampage, Thanks for your reply !

seadoosnipe
04-30-11, 09:55 PM
Quick question. Other than regular maintenance why do they need to be cleaned? When they are dirty will the engine run poor? Also, (this might be a dumb question) what do the rave valves even do? Thanks

RAVE is acronym for "rotax automatic variable exhaust". It is patented and is why the 787cc is capable of making 110hp, for such a small engine. In the days I built high performance 327 and 350 cu.in. motors, all my friends would brag about how they just bought a 650 or 850 cfm Holly carb and was going to beat me come Friday's race. I had a simple 4 barrel quadra-jet at the time. No frills, no big money. But, I did remove my 1:98 heads and went to the 2:02 heads. This gave me a larger exhaust port. The theory is, if you want to burn more fuel, you have to be able to exhaust that fuel. No matter how much fuel you dump in an engine, if you can't exhaust the expanding gases, then your not making anymore power.

The RAVE design is set up so that when you increase throttle, building rpm and horsepower, the exhaust pressure increases through the internal porting of the RAVE housing pushing up agains't the spring tension of the bellows, overcoming it and opening the slide valve. As the slide valve opens, it makes the porting large enough to exhaust more gases. This is where you get the extra rpm and horsepower.

The reason we clean them is simple. The 2 stroke motor mixes oil for lubrication of the roller bearings in the crank, wrist pins and main bearings. Most all the fuel is burned off in combustion. The oil we use is a low ash, which means it does have some carbon exhausted. The slide valve is the first moving part that comes in contact with that carbon (soot). It will build and gum up the slides for your guillotine valve, causing it to stick as it's trying to open. If you've ever been on the water and when going to WOT, there is a hesitation between 4 and 6K rpm, that's usually due to a sticking RAVE. If it's bad and your on the water, you can back off your red caps a few turns. This will alleviate the sticking, but don't use that as a reason not to clean them.

I would like to make one quick statement. The RAVE guillotine valve is easily cleaned with brake/carb spray cleaner and a piece of wood stick. I know everyone has their different ways of doing things, but whenever you use a piece of metal to clean another piece of metal, always make sure the metal you are using to clean with, is of a softer type. For instance, the RAVE slide valve is made of aluminum. Use copper or brass to as your wire wheel. Don't use a Stainless wire. You will not only be removing the carbon build up, you'll be removing the aluminum metal of the slide and in a few years, it won't fit the grooves anymore.

tony8a
05-09-11, 05:52 PM
very good info!!!
thanks!
i was reading about rave valves and i found it accidently...

dooser
05-10-11, 10:26 AM
Thanks for that info Snipe. This is good to know for future reference. I will be cleaning mine come this season. Thanks again!!:thumbsup:

seadoosnipe
05-10-11, 05:40 PM
Your welcome Dooser, but thanks to Rampage for such a good write up, along with some great pix!!!!

For a novice, I think people look at them, without much understanding of them and have a certain amount of trepidation about tearing them down for cleaning. For someone who isn't a real experienced mechanic, this is one of the easiest forms of maintenance that should be done, that anyone with a few tools can do.

In a lot of situations, there are people who have a problem with oil leaking into the bellows, or out around the RAVE, even melted caps. If you are having this problem, then you likely have a leak somewhere. If the RAVE is sealed, no leaks around the bellows, the air inside is stagnant and really doesn't get all that hot. The most common way for hot gases and oil to permeate the RAVE cap or bellows is from where the bellows connects to the bottom of the RAVE housing. In most cases, it is attached by a small tie wrap. Then, the excess is cut off. I've seen the knuckle of this tie wrap cut into the rubber of the bellows, allowing hot gas and oil to pass through.

The best way to keep this from happening is to use the smallest possible tie wrap you can get, then, before attaching it to the bellows and body of the rave, smooth off the top corner piece. This will keep from putting pressure on the bottom side of the bellows.

BMANN06
05-10-11, 06:22 PM
Great post thanks rampage! Thanks snipe for the idea of tie wraps too, last time i was in there cleaning these I noticed the steel retaining rings are getting weaker and weaker every time I pull these apart!

Good call on the sticky too!!

seadoosnipe
05-13-11, 12:20 AM
You gotta have the spring for the top cap of the bellows but where the bellows connects to the base housing of the RAVE, I use the little tie wraps. They fit the groove well and I've never had a problem with them; except one time I used one that was too big and it caused a hole to be rubbed in the rubber. That's when I came up with the idea of knocking off that top piece of the knuckle of the tie wrap.

At my "Advanced" auto parts store, they have a table with a bunch of low cost stuff on it. The tie wraps are in a round container with a lot of different size and colors, all for $5 bucks.......

Ninetok
05-14-11, 03:54 PM
I have used the spark plug hole O-rings they fit the bottom of the bellows perfect and no more leaks.

davistek
06-15-11, 07:39 AM
Great write up! I am going to get mine cleaned up and hope that it solves some issues that I am having.

pmartell12
06-19-11, 02:16 PM
thanks for the write up, it helped build my confidence enough to try to clean them, and it's a good thing because I found the previous owner lost one of the springs that holds on the rubber boot... all better now

Rampage
07-13-11, 04:11 PM
Just wanted to add a side note on this. If you use a high grade oil in your ski, you will not have to service these as often.

scorpio67
07-17-11, 09:53 PM
Hello, new here so not sure about proper procedure, but i have a question about the rave valves. I cleaned mine on a 96 xp i just bought. I was wondering if the valves should fall on its own if you lift it up a little?? Mine are really clean now, they were seriously gooed up, but when i slightly lift up on the bellows and valve it does not fall back down. Is that normal?? Thanks a lot, this forum is an awesome resource!!

bigJake
07-17-11, 10:09 PM
Hello, new here so not sure about proper procedure, but i have a question about the rave valves. I cleaned mine on a 96 xp i just bought. I was wondering if the valves should fall on its own if you lift it up a little?? Mine are really clean now, they were seriously gooed up, but when i slightly lift up on the bellows and valve it does not fall back down. Is that normal?? Thanks a lot, this forum is an awesome resource!!

they should move up and down freely. sounds like the slots the raves fit into are gummed up too and need cleaned out

scorpio67
07-18-11, 12:24 PM
they should move up and down freely. sounds like the slots the raves fit into are gummed up too and need cleaned out Thanks for the reply! Just to verify, mine move up and down just fine, but i have to actually push it back down myself, are you saying that it should close or fall on it's own when i let go of it?? Thanks again.

bigJake
07-18-11, 12:29 PM
Thanks for the reply! Just to verify, mine move up and down just fine, but i have to actually push it back down myself, are you saying that it should close or fall on it's own when i let go of it?? Thanks again.

hmm, I usually just put them in and and move the bellows up and down a couple times to make sure they are moving freely but never really paid attention to if it closes by itself. I assume but have to run outside and check. Gimme 5 minutes. But in the meantime are you 1000% positive you put the valves in facing the proper direction? If they are facing the wrong way, you are going to have broken valves and piston damage.

bigJake
07-18-11, 12:44 PM
Thanks for the reply! Just to verify, mine move up and down just fine, but i have to actually push it back down myself, are you saying that it should close or fall on it's own when i let go of it?? Thanks again.

ok, went out and ckecked. Mine don't close by themselves either. During operation, it is the spring inside the cap that holds the valve closed, as the pressue of the exhaust increases it overcomes the tension of the spring and opens the valve.

scorpio67
07-18-11, 02:05 PM
ok, went out and ckecked. Mine don't close by themselves either. During operation, it is the spring inside the cap that holds the valve closed, as the pressue of the exhaust increases it overcomes the tension of the spring and opens the valve.

Hey thanks a lot for taking the time to go and check on your machine, that is exactly what i needed to know!! That makes sense now that you say it!!

speedknot
07-31-11, 02:51 PM
they should move up and down freely. sounds like the slots the raves fit into are gummed up too and need cleaned out

Is there a proven method for removing the crud out of the rave slots without it falling inside? I have to have at least 1/16" of gunk in that slot.

Dakota881
08-03-11, 12:38 PM
Nice piece thanks

Rampage
08-03-11, 02:33 PM
Is there a proven method for removing the crud out of the rave slots without it falling inside? I have to have at least 1/16" of gunk in that slot.

I just used a rag and a screw driver!

Tacomatrx450
08-09-11, 02:29 AM
Quick question, my 1997 xp was spitting out a bit of oil from one of these valves, is this normal, or signs that it needs to be cleaned

bigJake
08-09-11, 11:06 AM
Quick question, my 1997 xp was spitting out a bit of oil from one of these valves, is this normal, or signs that it needs to be cleaned

needs cleaned. something may have come apart inside too. Whenever I've seen them spitting oil, it needed a new o-ring or the bellows disconnected.

Tacomatrx450
08-09-11, 01:26 PM
Sounds good thanks I will check it out this sat, do u know where I can find a o ring replacment?

bigJake
08-09-11, 02:31 PM
Sounds good thanks I will check it out this sat, do u know where I can find a o ring replacment?

You can select PARTS at the top of the page to order from this site.

speedknot
08-09-11, 03:10 PM
Sounds good thanks I will check it out this sat, do u know where I can find a o ring replacment?

See if one of you local shops have it first. Its sometimes a stocked part. Also, do a google search for rave rebuild kits. The kit comes with the o-ring, gasket, and bellow. I just waited two weeks for an OEM o-ring and gasket. I wish I would have found the rebuild kit first. Wouldnt have had to wait so long.

Thumper3322
08-26-11, 04:49 PM
Great write up, will definitely help when I clean mine.

Question.... I have read in different places, that the red cap can either be flush with the black boot (more high end speed) or down (in) a bit in the boot (low end power). Mine are set down (in) a bit, how can I change them to be flush? Does it have to be taken apart? If so, what inside would I have to change to make it flush with the boot?

Thx!!

bigJake
08-26-11, 05:00 PM
Great write up, will definitely help when I clean mine.

Question.... I have read in different places, that the red cap can either be flush with the black boot (more high end speed) or down (in) a bit in the boot (low end power). Mine are set down (in) a bit, how can I change them to be flush? Does it have to be taken apart? If so, what inside would I have to change to make it flush with the boot?

Thx!!

just put a screwdriver in one of the slots in the red cap and turn it. nothing to do inside. turning the cap out just reduces the pressure on the spring and allows the valve to open sooner.

Thumper3322
08-26-11, 08:37 PM
just put a screwdriver in one of the slots in the red cap and turn it. nothing to do inside. turning the cap out just reduces the pressure on the spring and allows the valve to open sooner.

Thanks, great to know!

However, just today one of my red caps blew out, basically I have no red cap, took off the spring clip over the black valve cover and under neath there is kinda a mess with a hole in a plastic part (see attached). Think I only need to replace that top black piece and red cap? Unless I find the red cap? lol. These hard to come by?

Why would it blow out like that? I checked before I went and all looked well, and the red cap was not flush, but in a bit. urg!

Sorry for the pics, at night with my phone and a flash light on my head.

bigJake
08-26-11, 09:04 PM
Thanks, great to know!

However, just today one of my red caps blew out, basically I have no red cap, took off the spring clip over the black valve cover and under neath there is kinda a mess with a hole in a plastic part (see attached). Think I only need to replace that top black piece and red cap? Unless I find the red cap? lol. These hard to come by?

Why would it blow out like that? I checked before I went and all looked well, and the red cap was not flush, but in a bit. urg!

Sorry for the pics, at night with my phone and a flash light on my head.

did you remember to put the O-ring back on the RAVE when you cleaned it and put it back together?
I would replace the O-Rings.

If you take it apart can you move the RAVE freely up and down in the slot?
Are you using the correct oil? API-TC fully synthetic low ash
there is a small hole in the base of the rave valve, less than 1/8 in diameter, make sure that is not clogged
if looks in your picture like the top of the bellows is securely in the groove of the exhaust piston (the black plastic piece) make sure that the bottom of the bellows is attached properly in the lower groove.
back the red caps out to flush

you can get the parts from this site - click PARTS at the top of the page.
http://partsfinder.onlinemicrofiche.com/seadooforums/Seadoo_oem/Seadoo_PWC.asp?Type=13&A=60&B=5

you can also try parkeryamaha or partspitstop

bigJake
08-26-11, 09:06 PM
did you remember to put the O-ring back on the RAVE when you cleaned it and put it back together?
I would replace the O-Rings.

If you take it apart can you move the RAVE freely up and down in the slot?
Are you using the correct oil? API-TC fully synthetic low ash
there is a small hole in the base of the rave valve, less than 1/8 in diameter, make sure that is not clogged
if looks in your picture like the top of the bellows is securely in the groove of the exhaust piston (the black plastic piece) make sure that the bottom of the bellows is attached properly in the lower groove.
back the red caps out to flush

you can get the parts from this site - click PARTS at the top of the page.
http://partsfinder.onlinemicrofiche.com/seadooforums/Seadoo_oem/Seadoo_PWC.asp?Type=13&A=60&B=5

you can also try parkeryamaha or partspitstop

also, they are not in the picture, but I'm assuming you have the springs that go on top of the plastic piston and they were installed

Seadoobuddy
08-26-11, 09:41 PM
Rampage and Seadoosnipe - thank you for the pictures and advice. I wish i had cleaned mine last week when I replaced all the lines. I doubt if they have ever been cleaned in 15 yrs. ........another day another project......

Can the gasket be saved or isn't it worth trying?

Thumper3322
08-26-11, 10:00 PM
did you remember to put the O-ring back on the RAVE when you cleaned it and put it back together?
I would replace the O-Rings.

If you take it apart can you move the RAVE freely up and down in the slot?
Are you using the correct oil? API-TC fully synthetic low ash
there is a small hole in the base of the rave valve, less than 1/8 in diameter, make sure that is not clogged
if looks in your picture like the top of the bellows is securely in the groove of the exhaust piston (the black plastic piece) make sure that the bottom of the bellows is attached properly in the lower groove.
back the red caps out to flush

you can get the parts from this site - click PARTS at the top of the page.
http://partsfinder.onlinemicrofiche.com/seadooforums/Seadoo_oem/Seadoo_PWC.asp?Type=13&A=60&B=5

you can also try parkeryamaha or partspitstop

Thanks for your feed back!! I never tried to clean them, I haven't touch them yet. I found the spring in the bottom of the seadoo. I'm guessing the spring came out some how?!?! The valve moves freely and doesn't look that bad. XPS is run in it. I will have to get a new gasket, o-ring, red screw top and that black piece that the spring sits on (see pic completely Fed). What's that piece called? Trying to find it in the manual says (exhaust valve)?

Looking at it, how do you get the rubber bellow over the lower groove and that small spring back around it? That looks like a real bitch!

I hope they carry these in their service department!

The valve itself I left in the machine with a cloth over it to stop dirt getting in until I can fix it.

bigJake
08-26-11, 10:48 PM
Rampage and Seadoosnipe - thank you for the pictures and advice. I wish i had cleaned mine last week when I replaced all the lines. I doubt if they have ever been cleaned in 15 yrs. ........another day another project......

Can the gasket be saved or isn't it worth trying?

if the gasket is still in good shape it can be reused, you'll be able to tell from the oil pattern on it if it is leaking

Thumper3322
08-26-11, 10:53 PM
The gasket was fine, no leaking, but there is a small rip in it, so will get a new one.

Do you know what that part is called? and how do you get the rubber bellow over the lower groove and that small spring back around it?

bigJake
08-26-11, 11:11 PM
Thanks for your feed back!! I never tried to clean them, I haven't touch them yet. I found the spring in the bottom of the seadoo. I'm guessing the spring came out some how?!?! The valve moves freely and doesn't look that bad. XPS is run in it. I will have to get a new gasket, o-ring, red screw top and that black piece that the spring sits on (see pic completely Fed). What's that piece called? Trying to find it in the manual says (exhaust valve)?

Looking at it, how do you get the rubber bellow over the lower groove and that small spring back around it? That looks like a real bitch!

I hope they carry these in their service department!

The valve itself I left in the machine with a cloth over it to stop dirt getting in until I can fix it.


yes, the melted plastic piece in your 2nd pic is #9 in the diagram called the exhaust valve.
http://partsfinder.onlinemicrofiche.com/seadooforums/Seadoo_oem/Seadoo_PWC.asp?Type=18&A=60&B=5&Action=O

is that ring on the right of your first pic a rubber o-ring or a spring ring? Stock, there is nothing around the base of the o-ring (note nothing in the parts diagram) some people put rubber o-rings or small zip ties. I don't put anything around the base on mine and never had a problem.

the valve on the rear of the engine you can fully assemble in your hand then stick in in one piece (excluding the spring and the black cap with the red button).

the valve on the front you have to put the gasket on the rave and put it in the slot, then attach the bellows to the base and put the bolts in. Then you screw the plastic exhaust valve onto the top of the rave. the bellows will usually seat itself in the groove on the exhaust valve once you get it screwed tight. you may have to help it a bit. the hardest part is then getting the spring ring around the top of the bellows, that takes some practice.

The o-ring I was asking about in the prior post is #4 in the diagram. I'm betting that is what caused your valve to melt. when i got my skis, one of the valves was stuck and melted like yours and there were just remnants of the o-ring remaining.

can't tell from the picture if the inside of your bellows is melted and needs replaced or if that is just oil

Thumper3322
08-26-11, 11:33 PM
yes, the melted plastic piece in your 2nd pic is #9 in the diagram called the exhaust valve.
http://partsfinder.onlinemicrofiche.com/seadooforums/Seadoo_oem/Seadoo_PWC.asp?Type=18&A=60&B=5&Action=O

is that ring on the right of your first pic a rubber o-ring or a spring ring? Stock, there is nothing around the base of the o-ring (note nothing in the parts diagram) some people put rubber o-rings or small zip ties. I don't put anything around the base on mine and never had a problem.

the valve on the rear of the engine you can fully assemble in your hand then stick in in one piece (excluding the spring and the black cap with the red button).

the valve on the front you have to put the gasket on the rave and put it in the slot, then attach the bellows to the base and put the bolts in. Then you screw the plastic exhaust valve onto the top of the rave. the bellows will usually seat itself in the groove on the exhaust valve once you get it screwed tight. you may have to help it a bit. the hardest part is then getting the spring ring around the top of the bellows, that takes some practice.

The o-ring I was asking about in the prior post is #4 in the diagram. I'm betting that is what caused your valve to melt. when i got my skis, one of the valves was stuck and melted like yours and there were just remnants of the o-ring remaining.

can't tell from the picture if the inside of your bellows is melted and needs replaced or if that is just oil

It's number 9 in the diagram, but on the service manual it is number 20 lol. Thanks for looking into it!

that small ring is the small spring ring that goes on the bottom of the bellow which goes over the metal frame that is attached to the block. That is the one I'm worried about getting back on, not a lot of room to work. This rave one came off the one closes to the back, so I'm guess it is the first one you are mentioning there.

I will grab new o-rings where ever they are needed.

It is just oil, haven't cleaned it yet, but looks all fine, just the exhaust valve is done.

Thx again!

bigJake
08-27-11, 10:10 AM
It's number 9 in the diagram, but on the service manual it is number 20 lol. Thanks for looking into it!

that small ring is the small spring ring that goes on the bottom of the bellow which goes over the metal frame that is attached to the block. That is the one I'm worried about getting back on, not a lot of room to work. This rave one came off the one closes to the back, so I'm guess it is the first one you are mentioning there.

I will grab new o-rings where ever they are needed.

It is just oil, haven't cleaned it yet, but looks all fine, just the exhaust valve is done.

Thx again!

try putting the small spring clamp on the bellows BEFORE you attach the bellows to the housing, then just roll it down into the groove. I think that approach will work for you

brock1
08-27-11, 10:22 AM
where did you guys get the gaskets for the raves i am having trouble finding them around me

bigJake
08-27-11, 10:25 AM
I've gotten them from this site and from parkeryamaha in the past, but would suggest just buying a sheet of gasket material at the auto parts and making them yourself

Seadoobuddy
08-27-11, 10:43 AM
Brock, try this place.
MotorCity Power sports
248-858-2300
www.motorcitypowersports.com

They are in Bloomfield Hills, Michigan on Telegraph about 1 mile or so South of M-59

Thumper3322
08-27-11, 09:17 PM
try putting the small spring clamp on the bellows BEFORE you attach the bellows to the housing, then just roll it down into the groove. I think that approach will work for you

Thanks so much Bigjake!! I had to make a long drive, but got the exhaust valve, extra gaskets rings etc. Man the main rave valve is a pain in the ass to clean. Lots of carb cleaner and brass brush 45 min of scrubbing. Got it cleaned as best i can. Got everything back together in like 5 min., very easy. To put the big spring on around the exhaust valve and bellow, stuck the handle of a fly swatter between the bellow and the metal casing so it couldn't bend in, and popped the spring on in seconds lol. Thanks a bunch for your help! Much appreciated!

Thumper3322
08-27-11, 09:21 PM
where did you guys get the gaskets for the raves i am having trouble finding them around me


I just called many seadoo dealerships/services, they all seemed to have the gaskets, just not the exhaust valve which I needed.

bigJake
08-27-11, 10:04 PM
I just called many seadoo dealerships/services, they all seemed to have the gaskets, just not the exhaust valve which I needed.

you may have to order online

Tacomatrx450
09-07-11, 06:34 PM
I had a chance to check mine today, the one that was spitting oil was missing the spring that fastens the below. I order some new parts and cleaned up what i could. Hopefully that should be the fix thanks again

ggarcia
10-07-11, 03:32 PM
Thank you very much! Very much helpfull.

Rampage
10-29-11, 10:57 AM
glad to see this thread still being useful :)

crisso
10-29-11, 12:08 PM
3 cans of spray and those bugs still run around my screen.They must be on the wrong side of the Windows:)

ALFONZO PINEDA
12-02-11, 11:13 PM
Found this thread very helpful and easy to follow. It helped clear up a bunch of questions i had about the rave system. Hope me replying moves it up on the list so other newbees can see it. Thank you again and i will keep reading.

eyecatcher201
02-17-12, 01:06 AM
Doing a rebuild on my 787. Using .5 oversize. Instructions in Piston box: "when installing any piston .5mm (.020) or larger, you must file down your Power Valves (rave valve) .015 Thousands.... Failure to do so will result in SERIOUS DAMAGE TO THE PISTONS.

How do you file down the rave valve evenly to .015? My auto shop won't do it.


I was thinking of using a finishing sand paper 600 grid or so attached to an old piston to get the correct curve and us this as a way of removing .015.











RAVE is acronym for "rotax automatic variable exhaust". It is patented and is why the 787cc is capable of making 110hp, for such a small engine. In the days I built high performance 327 and 350 cu.in. motors, all my friends would brag about how they just bought a 650 or 850 cfm Holly carb and was going to beat me come Friday's race. I had a simple 4 barrel quadra-jet at the time. No frills, no big money. But, I did remove my 1:98 heads and went to the 2:02 heads. This gave me a larger exhaust port. The theory is, if you want to burn more fuel, you have to be able to exhaust that fuel. No matter how much fuel you dump in an engine, if you can't exhaust the expanding gases, then your not making anymore power.

The RAVE design is set up so that when you increase throttle, building rpm and horsepower, the exhaust pressure increases through the internal porting of the RAVE housing pushing up agains't the spring tension of the bellows, overcoming it and opening the slide valve. As the slide valve opens, it makes the porting large enough to exhaust more gases. This is where you get the extra rpm and horsepower.

The reason we clean them is simple. The 2 stroke motor mixes oil for lubrication of the roller bearings in the crank, wrist pins and main bearings. Most all the fuel is burned off in combustion. The oil we use is a low ash, which means it does have some carbon exhausted. The slide valve is the first moving part that comes in contact with that carbon (soot). It will build and gum up the slides for your guillotine valve, causing it to stick as it's trying to open. If you've ever been on the water and when going to WOT, there is a hesitation between 4 and 6K rpm, that's usually due to a sticking RAVE. If it's bad and your on the water, you can back off your red caps a few turns. This will alleviate the sticking, but don't use that as a reason not to clean them.

I would like to make one quick statement. The RAVE guillotine valve is easily cleaned with brake/carb spray cleaner and a piece of wood stick. I know everyone has their different ways of doing things, but whenever you use a piece of metal to clean another piece of metal, always make sure the metal you are using to clean with, is of a softer type. For instance, the RAVE slide valve is made of aluminum. Use copper or brass to as your wire wheel. Don't use a Stainless wire. You will not only be removing the carbon build up, you'll be removing the aluminum metal of the slide and in a few years, it won't fit the grooves anymore.

seadoosnipe
02-27-12, 04:58 PM
You could take it to a machine shop who deals in high performance parts, they should do it.

But, though the 787cc motor is stock with a bore of 3.228" and recommended for a bore over of .10 (3.238"), it's not recommended to bore over .20". If you do, you will need to shave your guillotine slide valves. Since it's not a huge amount and there is a small amount of tolerance, I don't see why you can't do it yourself.

If I were going to do it, I'd take an old piston, lock it down on my workbench, then use it as a jig to grind my slide valve. Hope it works out for you........

JoeStrange
03-23-12, 02:30 AM
This thread is extremely helpful considering I didn't know what a RAVE valve was until a few days ago.

I drove down to Michigan City Indiana and bought two 1996 Seadoo XP on a double trailer for 3K on Sunday, VIN#s say their a matched pair. A and B. That oddly enough were originally purchased from Lake Orion Michigan which is where I live. They have returned home hahaha.

So anyways, These are my first ski's, They both started on a dime when the old owner fired them up for me. When I was inspecting the hulls and engine bays I noticed that one of the RAVE valves was leaking oil, But at that point I didnt even know the lil red caps were valves.

So I got home and started bouncing around forums learning about this setup, How it functions and what maintenance was key to keeping a reliable machine. First off, I know nothing about 2 stroke motors. I never owned one. But I have a lot of experience in auto so i'm diggin right in to it.

I just pulled the leaking valve housing off and that little 10mm plastic nut was melted inside of the spring. There was the red rubber, bellows? (I need to figure out the names of all these parts) with a spring around it that looked to be ok but the rubber black piece is damaged its hole is melted and reamed out just like the picture in post #40

I went ahead and removed the two alan bolts and separated the lower housing from the head. The gasket looked to be in good condition. On closer inspection I remembered there was suppose to be an O ring somewhere, But Its not there. Im looking at this groove that looks like there should be an O ring there and there's not. Maybe it got melted away? Hahaha.

I want to rebuild and clean all of these, The amount of shit thats on these parts is epic compared to the OP pictures. I went in with no rubber gloves, I wont be doing that again.

So whats the deal with the RAVE valve on the exhaust? Should i go ahead and rebuild that too? If I did, that would make 6 that I have to do. I noticed SeadooBuddy mentioned MotorCity Powersports, I drive by there every day. I'll try them first for the rebuild kits.

Im going to start my own thread with pictures so I can go over everything, Not just RAVE valves cause summer is fast approaching here and I wanna ride! Which means I gotta fix these fast! Michigan has had a streak of 70s and 80's for the past two weeks and I got the fever!

rckstr
04-17-12, 10:10 PM
I have a 2000 RX and decided to clean the RAVE valves. I took the first one out with ease and quickly sat it down not paying attention to which way it went back in. I figured I could look at the 2nd one to figure out which way it went back in but now I am questioning myself thinking they could go opposite ways. I am going to take them back apart tomorrow and i have read they may be stamped with TOP on them but since they are vertical, which way is top? Thanks guys. As of now, i have them both the same way (the concave of the valve)

LouDoo
04-17-12, 10:14 PM
One side of the valve it marked "TOP", the top goes toward the spark plug.

Lou

Seadoobuddy
04-17-12, 10:15 PM
it's marked "TOP", that side faces the pistons.

this is post #3...
Yeah its not really the best write up but I hope it will help someone....On a side note, it's very very important to put the Valve back in facing the right direction....mine is stamped TOP on one side, and that it the side that should be facing the pistons.

rckstr
04-17-12, 10:19 PM
So is it the spark plug or the piston?

Seadoobuddy
04-17-12, 10:21 PM
They are basically both in the same direction.

rckstr
04-17-12, 10:23 PM
Thanks guys

LouDoo
04-17-12, 10:52 PM
The side marked TOP faces the spark plug, the side with the double notches faces the piston, the bevel is down. This is what they should look like when putting them back in, the notch on the base must face the exhaust manifold. When you install the raves you should be able to read the word TOP.

Lou

JoeStrange
04-17-12, 11:46 PM
I need an opinion from you guys.

When I pulled this RAVE valve, What they call the "Exhaust Piston" was melted and by the looks of the RAVE it had just been dancing around in the cylinder because as you can see the edges are slightly bent and theres aluminum burrs on the edges. The burrs are hard to see in the pictures but if I use this RAVE they definitely have to be filed off.

On the TOP side theres seems to be more wear on the edge than the 3 others I pulled. Question is, Should I reuse this RAVE or get another one? I have the rebuild kits but i'm not sure if I should reinstall this or not?

That 3rd picture has a sharp jagged edge,while all the other RAVES I have are smooth on the edges, not sharp.

Thumper3322
04-18-12, 12:05 AM
Be safe, get new. Been there done that lol.

Ninetok
04-18-12, 08:10 AM
Joe it
Looks like someone shaved them down for oversize pistons. I would pull the head to make sure if you put new ones in with out shaving them you will damage your pistons.

rckstr
04-18-12, 08:58 AM
Well I pulled mine out and neither side has TOP stamped on it. Also both sides are smooth, no grooves. Both valves are identical

LouDoo
04-18-12, 09:25 AM
Since you have a 951 they are a little different. I couldn't find any pictures on this site but I did find a pretty good pictorial. The 951 rave valves are not marked and maybe it doesn't make any difference which way they go in, I would do it like this pictorial shows. The beveled side goes toward the engine, the flat side toward the vacuum connection.

http://www.theudells.com/PWC/other/rave/rave.htm

Lou

Ninetok
04-18-12, 10:19 AM
Dang Lou i was looking at your link. Man what kind of oil was he using? must have been some cheap oil.

JoeStrange
04-18-12, 10:25 AM
Joe it
Looks like someone shaved them down for oversize pistons. I would pull the head to make sure if you put new ones in with out shaving them you will damage your pistons.


Does it really look shaved to you? To me it just looks like the others I have, Like they have been wire wheeled ten thousand times.

I never thought about these motors being bored over from a previous rebuild, That messes my whole world up.

Ninetok
04-18-12, 10:32 AM
The margin on the end just looks a little wide to me I cant really tell but mine don't look that wide. On my other ski it was bored 1mm over and looks like yours. One way to tell is to pull head and see if pistons are marked won't hurt any thing to make shure before you put new ones in.

rckstr
04-18-12, 11:12 AM
Thanks Lou. I got her back together. I have moved on to the impeller pump oil. Got it all cleaned up and ready for new oil. What weight should I use? I have 75w-90 synthetic. Will that be sufficient?

LouDoo
04-18-12, 12:19 PM
Thanks Lou. I got her back together. I have moved on to the impeller pump oil. Got it all cleaned up and ready for new oil. What weight should I use? I have 75w-90 synthetic. Will that be sufficient?

That's good.

Lou

RFoster130
04-18-12, 01:03 PM
Thanks Lou. I got her back together. I have moved on to the impeller pump oil. Got it all cleaned up and ready for new oil. What weight should I use? I have 75w-90 synthetic. Will that be sufficient?

That is exactly what it takes. Just over 2 oz per cone.

rembocanoe
06-02-12, 03:28 PM
Awesome Write up.
Quick question...
I'm rebuilding a 787 for my challenger using a 787 outa gtx.
I noticed that the rave valves (guillotines) are different. The challenger has 2 groves in it like the one in his pic above.
But the gtx does not have grooves.
Why the difference and which is better?

Thanks

LouDoo
06-02-12, 04:19 PM
The rave valves with the grooves are just the new style, they're interchangeable.

Lou

rembocanoe
06-02-12, 10:54 PM
Ok thanks... I pulled the flywheel today..had to put the heat to it.. even with the puller. I've pulled other before and never had to heat. Now the crank seems a little stiff to rotate.. hope I didn't booger anything up.

And I'm sure there are post on the cranks and the balancer and worm gear. But is there any general rule (trick) on making sure that when I pull the crank that I get it lined up with the balancer and the worm gear during reassembly?

rembocanoe
06-03-12, 04:10 PM
12884
Here is the different raves I was talking about lou. I also noticed that the housing is different too. The rave on right is from the challenger then one on the left from a gtx. both 787 and both 1997.
Well I was tryin to paste a pic.. obviously im not as computer smart as I thought I was. LOL

lamajama
10-21-12, 12:35 PM
Doing my end-of-season RAVE cleaning I noticed on one of the valves that the "angled" portion's surface was pitted a bit and
the surface metal was gone in a few areas (angled portion). The valve was not that clean considering that I had done them about 5 hours before (late season purchase) but I'm attributing some of that to whatever oil was/is still being used (the tank was full when I got the
machine). I'm just wondering if that additional friction on the angled portion would be an issue and if I should replace the valve?

Steenkamp
12-15-12, 07:09 AM
Nice info..will love to use it whenever i encounter such prob..

LouDoo
12-15-12, 08:00 AM
Nice info..will love to use it whenever i encounter such prob..

Servicing rave valves is not a problem, it's a maintenance item and depending on how much you ride should be performed on a regular basis, at least once a year.

Lou

aparke4
07-23-13, 10:28 AM
great thread!

I just got a new to me 98 speedster and man are the RAVEs gunked! I do not think they have ever been cleaned... all 4 are in poor shape with an 1/8 of gunk in some places.

I completely drained the old oil and switched over the amsoil intercepter with new oil filters and it already smokes way less and seems to be much happier. I think the PO might have been using a cheap oil and did very little to zero maintenance b/c it came with autolite truck plugs gapped at .040!!

It is running much smoother and quieter with new plugs, oil and clean raves. Thanks seedooforum!

sheffs
08-13-13, 04:24 PM
i have a question im new to this so i need some help i have pulled off my rave valves and cleaned them on a 98 gtx limited my question is what is the easy way to assemble the spring back on that hold the bellows to the bottom and top


thanks
sheffs

Paul Rock
08-14-13, 03:02 PM
Rampage awesome job. We printed out your thread and took care of an issue we had. Thank you.
Thanks to all others for the extra advice.
This forum is great.:thumbsup:

Rampage
08-14-13, 03:09 PM
Rampage awesome job. We printed out your thread and took care of an issue we had. Thank you.
Thanks to all others for the extra advice.
This forum is great.:thumbsup:

Glad I could help!! :) Also glad to see this thread still alive. Just to add to the thread.. The type of oil you use will greatly affect how gunky your Rave valves will get.

Paul Rock
08-14-13, 03:19 PM
Glad I could help!! :) Also glad to see this thread still alive. Just to add to the thread.. The type of oil you use will greatly affect how gunky your Rave valves will get.

We use only the best available. Learned that from all you who impart your wisdom on us rookies. I almost look like I know what I am doing when I have my head buried in the engine compartment, I even sound like I know what I am talking about.

Thanks again.

grhonk
08-22-13, 09:44 PM
You gotta have the spring for the top cap of the bellows but where the bellows connects to the base housing of the RAVE, I use the little tie wraps. They fit the groove well and I've never had a problem with them; except one time I used one that was too big and it caused a hole to be rubbed in the rubber. That's when I came up with the idea of knocking off that top piece of the knuckle of the tie wrap.

At my "Advanced" auto parts store, they have a table with a bunch of low cost stuff on it. The tie wraps are in a round container with a lot of different size and colors, all for $5 bucks.......

I not entirely getting it .. what part of the tie wrap are you smoothing down? "Top piece of the knuckle" has me confused, believe it or not. Maybe a picture would help. I know this is an old topic, but I am still new to this RAVE stuff.

jifootman
09-04-13, 03:04 PM
Thanks for taking the time to put up this post. I'm a newbie and found this very helpful.

SDSeadooer
06-09-14, 09:20 PM
I have a 96 xp and after I took the cap off, I could not get the center nut ( plastic ) to break free so I could remove the bottom of the top cap off first, before I pulled the valve out. I cant get the front valve out with the cap still on because the exhaust manifold and tune pipe is in the way. Can any one tell me what I can do, so I don't have to pull the exhaust and still get the front valve clean?
Thanks

Ok I was trying to hold what looks like a spool right below the plastic nut while I broke the nut free, and nothing would move. IT's all 1 piece, if you can get the spool to turn, you can unscrew the whole thing off.

macedonia64
06-18-14, 10:10 AM
There hasn't been mention of gaskets. Im assuming its ok to make the gaskets from the appropriate gasket stock vs ordering the oem gasket?

Sent from my SAMSUNG-SGH-I747 using Tapatalk

SDSeadooer
06-18-14, 12:21 PM
Can anyone tell me when to know that your rave valve needs adjusting and how to do it?

LouDoo
06-18-14, 12:28 PM
Can anyone tell me when to know that your rave valve needs adjusting and how to do it?

Hi and welcome to the SeaDoo forum.

You would have much more success in getting your questions answered in either the meet and greet section or the 2-stroke PWC section. The how-to section is really an informational section and members rarely check it. Sorry for the misunderstanding.

Lou