How to make your carbon seal water cooled

[RXP rider]

Hi

First I would like to say that I´m from north europe and thats why my english ain´t
perfect

I work in a shop where we fabricate a lot of pumps, shaft and many more. From my work I know a lot about shaft and seals. In bigger pumps used in the industry a carbon shaft seal is ofen used. One of the things I know about carbon seals is that THEY CAN NOT RUN DRY.

My ski cavitated a lot and for that reason I did some testing. I pulled the driveshaft, carbon seal, and the rubber boot on my ski. I quickly noticed the surface of the ss support ring and carbon ring were worn and had burn marks from running dry and hot on the hose. That was what I expected to see. In the workshop I grinded the surface on the support ring and polished it ( see pic ) bought a new carbon ring and and I put it all together again. Fired up the ski ( IN THE WATER ) and ran it without cavitation at all. went home and ran it on the hose ( 1 min ) and launched the ski again and did a test run. This time I had a little cavitation not much but enought to piss me off. Back to the workshop and pulled the driveshaft, carbon ring and support ring again to find the support ring burned on the surface. From that I concluded that the carbon seal can´t run dry AT ALL.

I grinded and polished the carbon seal and support ring one more time and added a nice mod to my ski. which is a RXP 06. take a look at the pictures

What I did:

-Pulled the seat and all the stuff that makes it hard to get to the carbon seal.
1 Pulled the pump
2 Pulled the driveshaft, carbon ring and support ring.
3 Drilled a 6,5 mm hole in the pump tunnel through the hull and through hull bushing.
4 Cutted a piece of the copper pipe approx 180 mm
5 Bented the pipe the same angle that I drilled the hole in.
6 Fill the hole with right stuff to hold the pipe in place and seal arround the pipe
7 Grate some pieces of fiberglass ( I used 300 g matts ) you would like them to be approx 60 x 60 mm.
8 Mould arround the pipe ( I cutted some holes on the fiberglass mats ant stuck them on the pipe )
9 When the fiberglass is dry you can test fit the driveshaft and adjust the copper pipe to spray on the support ring ( see pic )
10 Before you connect a hose on the pipe, make sure you didn´t filled the pipe with polyester when you slided the wet fiberglass mats over ( I did ) then you will just drill the opening on the pipe with a appropriated size drill.
11 Find your hose that goes from the garden hose adapter and to the j-pipe ( the small hose conntcted on top of the j-pipe )
12 Cut the hose approx on the mittle and insert a T-piece ( your t-piece must have
2 x 12 mm connectors and 1 x 6 mm )
13 fine the hose that you just connected to the copper pipe and let it go up on the top of the engine or a place where you can reach it. Cut it there and insert the petrol tap with stainless steel clamps
14 Cut a piece of hose and let it goes to the t-piece on the small hose to j-pipe
15 put your ski togheter and you are ready to go

That way you have a watercooled carbon seal that will cool down the carbon ring and lube it when you run it on the hose. Remember to turn off the fuel tap before you launch the ski or water will fill the j-pipe.

Pleace notice that in the pic I don´t installed the fuel tap on the hose becouse the pic were from I test fitted it all.

[RXP rider]

[RXP rider]

[speedskixp]

Great idea. I've often thought of doing something similar but never have. They should come from the factory with something like that. Nice work. hope it works out for you . As long as there is no air in the cooling system to create cavitation I dont see why it wouldn't work.

---------- Post added at 01:20 PM ---------- Previous post was at 01:20 PM ----------

Forget the comment about air in the cooling system. LOL The valve will take care of that.

[sea-one]

Man that looks risky for cavitation to me... jmo

[speedskixp]

Man that looks risky for cavitation to me... jmo

That was my fist thought too but as long as it's sealed up good and strong and the valve is off it should be good IMO. However, there is alot of possitive and negative pressure going on to consider.

[RXP rider]

I have tested it with no cavitation at all. The only possibel way to get cavitaion is if there is a leak between the pipe and hull or a bad vavle right ? I even pulled the driveshaft and carbon ring when I had flushed it 5 times on the hose for a longer periode and the carbon ring og support ring are like new

[R88ory RXP]

good job, looks cool.

R88

[JPR]

nice work, thats pretty clever !

[SLASHER]

nice work, thats pretty clever !

I great simple idea ...well done ...