H2O in my Rave valves, why?

[thomas]

My ski started running like crap, bogging down/low power/felt like it was going to die, basically had to half throttle feather it to shore. Thought it was carbs, tore them apart, everything ok there. Checked fuel lines, seems ok, have bypassed fuel selector. But when I took off the Rave valves, water came out of the black crankcase/outside pressure hose. There was also water in the body of the raves. This could cause those symptoms, right?

So, how in the heck did it get there. I don't think it was from the crankcase as there is no sign of water intrusion. Can it get in the raves from the other outside atmoshphere hose end?

[Technical Support]

Re: H2O in my Rave valves, why?

What ski???

[Bill O'Neal2]

Re: H2O in my Rave valves, why?

That would be his 99 XP or any rave motor.

Water can get there from a bad exhaust manifold gasket, a blown head gasket or base gasket.

Has this motor been torn down for any repairs?

Were you riding where it could get water down the intake system?

[Denny Moran]

Re: H2O in my Rave valves, why?

I had a wierd one once, on a 97.5 Franco 86mm stroker engine.(same engine that Mel big bored, slid into his xp and smoked everyone at Body Beach in 98 or 99)

Kept getting traces of water in the front cylinder and water emulsion in the rave cavity. Slow leak on pressure tester ended up being from porosity down the gas port hole next to the rave slot!

Drilled it out and sleeved it with a bit of stainless steel 3/16 brake tubing. All fixed.

Not saying thats your problem though, just tellin a story!

[thomas]

Re: H2O in my Rave valves, why?

Yes, this is my 99 XPL and Yes, I recently installed another exhaust manifold for an EGT. Maybe the gaskets are leaking. But this was during the races at Long Beach. Very rough conditions, water everywhere. XPL sometimes a submarine.

[Bill O'Neal2]

Re: H2O in my Rave valves, why?

Thomas,
I'd take it to some smooth water and try it again, you may not have a problem with the gaskets in the exhaust system ( but you still could ) .

Water down the intakes can cause it to show up on the rave valves if the sloppy water conditions caused you to suck it down the carbs. The XP's, when I raced them, especially in Long Beach or any ocean type conditions ( Even at Havasu during the WF's ) I use duct tape around the hood where it meets the hull and around the back hatch cover to seal it off. I also ran outerwears on the filters. Tape off the vents in the front of the hull under the hood cover. I suggest moving those vents to the rear of the hood like on the later model XP's. Do everything possible to keep water out of the engine compartment. I always install duckbills when racing in the ocean, along with a working bilge pump.

When you finished racing, did you have alot of water in the hull?

[Bill O'Neal2]

Re: H2O in my Rave valves, why?

Denny,
I've seen that many times. In fact on the 787 Superstock clyinders with wide rave valves, we have to pick and choose which clyinders we modify and which ones we cannot modify for wide valves. The location of the hole drilled through the side of the exhaust port to supply the pressure to the rave valve piston varies on oem clyinders.

If you have a few clyinders laying around, look closely at where that hole is located in different sets of clyionders. You will see what I mean.

[Bill O'Neal2]

Re: H2O in my Rave valves, why?

Thomas,
You said you mounted an EGT equipt exhaust manifold. It is possible someone screwed up the installation of the EGT probes in the manifold, causing water to go from the water jackets into the exhaust ports.

That and/or leaky exhaust manifold gaskets can easily cause you to bend a rod. If you blow a rod out of the engine soon, you will know why. If you notice a loss of about 200-300 rpm in the motor, you probably bent a rod and it will break in half during the next hour of engine running time. Don't mess around if you notice a loss of rpm. No amount of tuning will get it back. Get the motor out and change the rods now or buy new cases, reeds, maybe a starter motor, clyinder, head and counterbalancer if it blows.

[thomas]

Re: H2O in my Rave valves, why?

Thanks for the advice Bill. Good question about the exhaust manifold, I'll take it off and check. But before that, I think I'll take it out to some smooth water like you said. If the rpm's come right back up to normal, then I'm ok on the crank. and I'll bet it WAS h2o during the race. Should have known better!