valve cover opening??

[kwlambeth]

ok so i know this thread my be in the wrong place but i wasnt sure where to put it. I have a 94 rinker 180 with a mercruiser 3.0 on top of the valve cover there is like a vent hole, there is a rubber hose attached to this with just a hose clamp and the hose just runs to the airfliter and stops, well oil is spitting out and after a day of riding it kinda creates an oily mess on most of the top part of the engine, whats the purpose? can i plug this hole? if not how do i stop the mess that its creating?

 

[CATransplant]

Re: valve cover opening??

That's the breather hose, and it ventilates the crankcase of your engine. What is the hose clamped to? There should be a metal tube that goes through a rubber grommet there. At the other end, it should do the same going into the air cleaner housing. If it's a loose fit, some oil from the valve train may well leak out and dirty things up.

Look inside your air cleaner housing. If it's really oily in there, then you probably have some serious engine wear, causing blow-by. No cure for that except an overhaul with new rings, etc.

Can you post a photo of the setup?

 

[LubeDude]

Re: valve cover opening??

There should not be that much oil coming out around there, the valve cover should be baffled. if it's going to the air cleaner then it is just an air intake to make up for the negative preasure caused by the PVC if it has one. If no PVC then it is a vent for crank case preasure. The above post is correct in that you may have an engine problem, do a compression check, and with the engine running pull the hose out of the valve cover and see how much preasure is coming out of the hole. There should not be much if any at all.

 

[CATransplant]

Re: valve cover opening??

There should not be that much oil coming out around there, the valve cover should be baffled. if it's going to the air cleaner then it is just an air intake to make up for the negative preasure caused by the PVC if it has one. If no PVC then it is a vent for crank case preasure. The above post is correct in that you may have an engine problem, do a compression check, and with the engine running pull the hose out of the valve cover and see how much preasure is coming out of the hole. There should not be much if any at all.

From the original post, I'm not even sure the hose is connected to the air cleaner. If it's a new boat to this owner, he may have inherited someone else's jerry rigging. He said it just stops at the air cleaner. I'm thinking it's just an open hose there.

You're right, of course. There shouldn't be all that much oil there at all. I'm betting there's a lot of blow-by going on here.

 

[kwlambeth]

Re: valve cover opening??

well the motor is basically brand new, myself and a friend just rebuilt it. i believe its just a vent or whatever for the valve cover, when the hose is off it is just spitting out little small droplets of oil, not very much so not alot of compression there, but just enough to cause a mess. and no the other end of the hose is not connected to anything, its attached to a metal bracket that goes across the air filter but the metal bracket doesnt actually plug the hose, its just connected to it.

 

[CATransplant]

Re: valve cover opening??

Well, that hose isn't supposed to just be there, open on the end like that. It will deposit some oil on your engine that way. Is the air cleaner some sort of replacement? The stock one will have a spot for that hose to connect to it, so that the oily vapors re-enter the carburetor and don't soil stuff.

Look at the engine on your car. See where a hose from the valve cover goes. If you have some sort of aftermarket air cleaner with no connection there, then I don't have an answer for you.

Again, a picture would help.

 

[erikgreen]

Re: valve cover opening??

That's a primitive form of pollution control that's meant to burn off the vapors from the valve cover area.

I have a pair of them on my V8, both go to the flame arrestor so the vapors get sucked into the engine.

If you rebuilt the engine, perhaps you added a flame arrestor without the hole for this hose?

Erik

 

[tashasdaddy]

Re: valve cover opening??

if it is pumping oil, better check compression, could be head gasket going.