Moisture on the RAVE valves after 1 minute of riding

[Boyd12]

I am getting some water on the RAVE valves in both cylinders which has never happened before in the 15 years of operation. The engine has just been rebuilt. It does not occur at idle or on the trailer in the water revving it up as I have specifically checked. Only when riding it and it only takes about 60 seconds of riding to take a dry valve and get it wet. See below.
Could it be an issue with the water control valve? Head gasket?
Thanks!

 

[Tyman2020]

Are you sure this is water? This thing sits inside the cylinder and is sprayed with fuel...However if it truely is water the only way i see this happening is your exhaust pipe gasket is failing. The compression of the stroke should keep the water out but could leave moisture in the high places such as here...Being you just had this motor out i would assume that its a new gasket and i cant stress oem gaskets enough.....Keep us posted...I guess a head gasket could cause water infiltration aswell but im sure it would run like crap. By water control valve what part is that...Is that on later xps never heard of it but ny experience is with 02 and back

 

[Boyd12]

Are you sure this is water? This thing sits inside the cylinder and is sprayed with fuel...However if it truely is water the only way i see this happening is your exhaust pipe gasket is failing. The compression of the stroke should keep the water out but could leave moisture in the high places such as here...Being you just had this motor out i would assume that its a new gasket and i cant stress oem gaskets enough.....Keep us posted

Thank you for your response! It is water. I agree it may be the exhaust pipe gasket, but it is new (doesnt mean good) All new gaskets all OEM.

 

[Tyman2020]

I would replace the 10 dollar gasket and see if that fixes your issue i would suspect your pipe is not filling enough on the hose to replicate your issue on the trailer.

 

[Boyd12]

I would replace the 10 dollar gasket and see if that fixes your issue i would suspect your pipe is not filling enough on the hose to replicate your issue on the trailer.

What do you mean "your pipe is not filling enough ..." I am unfamiliar with how this exhaust pipe cooling system works!

 

[Tyman2020]

Basically the cooling system is a open circuit so you are physically not holding water so on the hose your basically forcing water into the system when your pulling water from the pump the system is getting alot more flow with the same amount of allowed output causing your exhaust pipe reatin more water which could be causing your leak under operation only

 

[Boyd12]

Basically the cooling system is a open circuit so you are physically not holding water so on the hose your basically forcing water into the system when your pulling water from the pump the system is getting alot more flow with the same amount of allowed output causing your exhaust pipe reatin more water which could be causing your leak under operation only

OK. What I think is odd is that the water control valve redirects less water into the pipe (more into the muffler) at higher RPMs. I was thinking the valve could have an issue, but the problem occurs at higher RPMs and under a load.
The company that milled the head created a ridge. It passed the leak down test, but does that mean it will hold under load?

 

[Tyman2020]

A passed leak down test give me highly supsect not a issue with motor but maybe the valve you mentioned or a physical gasket. They build these things up to a certain pressure and check for leak down if that passed and they are good techs you should be good ive seen techs fuck up parts and falsify data

 

[Boyd12]

A passed leak down test give me highly supsect not a issue with motor but maybe the valve you mentioned or a physical gasket. They build these things up to a certain pressure and check for leak down if that passed and they are good techs you should be good ive seen techs fuck up parts and falsify data

I agree with you!
The facts are:
I have an engine with moisture in it
that passes a leak down test with a
head that has a ridge in it
with a new OEM exhaust pipe gasket
a possible water control vavle issue (it doesnt seem to make sense that the water control valve is the issue, although it could be)

My issue is nothing stands out! It COULD be any or all of the above!
I don't drink, but I am reconsidering!

 

[Boyd12]

One more thing, the RAVE valve image is the R valve. it has twice the moisture on it as is on the F cylinder.

 

[mikidymac]

With the engine running any water in the exhaust would be blown out by the combustion gases not into the raves. Only real way to get water on the raves is to have a bad head gasket.

Keep in mind the 951’s will show condensation on the raves and plugs after running and is why you need to fog a 951 after every ride.

 

[Boyd12]

With the engine running any water in the exhaust would be blown out by the combustion gases not into the raves. Only real way to get water on the raves is to have a bad head gasket.

Keep in mind the 951’s will show condensation on the raves and plugs after running and is why you need to fog a 951 after every ride.

I am leaning towards the head/ head gasket, but what is odd is that there is NO moisture until i ride it. Running it in the water on the trailer for 5 minutes, revving it up produces NO moisture on the valves. I think it is the head/gasket, but I have never seen one not leak at least some at idle, no load and then leak under load. It doesnt make much sense.

 

[mikidymac]

And your sure it’s not the normal 951 condensation?

 

[Boyd12]

And your sure it’s not the normal 951 condensation?

I have 15 years with the 951 and not once have I found moisture on the RAVEs unless there was a head gasket leaking. I have checked this thing MANY times and only find it after riding it.

 

[mikidymac]

Sounds like you already know the answer then.

 

[Boyd12]

Sounds like you already know the answer then.

If i had the answer (with any certainty) I wouldnt be asking, it is a logical contradiction.
"I have 15 years with the 951" I am not being a rectum, but stating I am not new to these engines.
"and not once have I found moisture on the RAVEs" another fact not being a rectum
"I have checked them MANY times" Over the years and with this current situation.
"and only find it after riding it." Literal statement. I have only ridden it a minute or two at a time and only to see if the moisture is showing up. My logic is if it does this in 1 minute, it will do about 20 times that in 20 minutes of riding. I consider that to be a problem and I dont want to find out the hard way I have an issue.
The facts are:
I have an engine with moisture in it
that passed a leak down test with a
head that has a ridge in it (OEM head gasket)
with a new OEM exhaust pipe gasket

My issue is nothing stands out! I dont want to go ripping and shredding for nothing.
I guess I will replace the exhaust pipe head gasket for gits and shiggles. If that doesnt do it, I will send the head to a machine shop and have it fixed.

 

[mikidymac]

Well it sounds like you still really question that head.

If it was me I would always be worried about it and it would drive me crazy. In my opinion I would get a good clean used head and rule that out instead of worrying about it all summer.

 

[Boyd12]

Since I have this issue, and the head is a possibility, then I must consider it in the list of solutions.
My plan was to replace or repair the head over the winter since it appears to be OK at present.
I have seen a few people online with this issue but no one posted the cure, so I thought I would try to find an answer here.
Thanks for the input.

 

[Boyd12]

I have read online that the water control valve on the muffler could be the issue.
I went to the lake again and when on the trailer, I removed the hose that runs from the water control valve on the muffler (I removed it from the exhaust pipe fitting) and revved the engine up. What I found was more RPM, more water came out of the hose. SD manual states the opposite. More RPM, less water to the exhaust pipe, more to the muffler.
Is the valve is operating correctly?

FYI: I removed and disassembled the valve and it is in excellent condition. the bellows is great, no sticking, no dirt/mud etc.