Valve cover leak.

[brwntom]

I just put a new valve cover gasket on because my old one was leaking a little. I bought the felpro rubber one with the brass stops formed into it. It now leaks really bad. There is oil sitting on the lip around the valve cover, every time I stop I can smell it burning on the exhaust manifold. Is there a trick to these gaskets?

Thanks,
Tom

 

[Mark_88]

Are you seeing the oil on the top of the lip (in the trough) or along the edge of the valve cover below the gasket?

If it is above in the trough then the leak isn't from the VC but the vent at the top (usually). If below the VC gasket line then you may want to try some RTV below the gasket...

How many miles on the truck? And how much pressure comes out of the VC vent on the top when you accelerate? You can test this by simply removing the vent hose and rev the engine...if you see quite a bit of pressure you may actually have a blow-by problem.

 

[Tractor Dan]

I second the rtv if it's the actual valve cover gasket leaking. I used rtv red on mine. Put a tiny bit at each corner and along the length at a few spots. So far no leaks and that was back in September.

 

[Scrambler82]

How does the lip of the valve cover look.
It should be flat and straight.
The inserts in the gasket will work but on a flat surface.

Use some high tack (sp) gasket spray, http://www.pepboys.com/product/details/8066534/
Spray the gasket, leave it set, lite spray just before using.

The RTV is good stuff but is hard to determine how much to tighten and how much to use.

 

[brwntom]

I think i found the problem.... kinda wanna kick my self in the butt for this one. where the gasket goes over the hump in the front of the motor where the cam shaft comes through, the gasket fell backwards into the valve cover. thus leaving a large area where it wasn't even sealed. I am going to try to tackle this right now.

Tom

 

[Mark_88]

Ah...been there and lost quite a bit of oil...lol...

I also didn't tighten the timing peg one time and had oil spurting out the front of the motor...hope that resolves it for you...

 

[brwntom]

Ah...been there and lost quite a bit of oil...lol...

I also didn't tighten the timing peg one time and had oil spurting out the front of the motor...hope that resolves it for you...

What is this thing that you are referring to as a timing peg?

 

[Mark_88]

On the older trucks (not sure about later models) there is a peg that holds the timing belt tension spring as well as the timing marker in place...it is just below the pulley on the camshaft and to the right...if you pull it out the hole goes right through to the head and oil on the top of the head can leak out...

With enough pressure in the valve cover or if you have blow-by it will actually blow out the hole...if the peg is not fully tightened oil can leak through there...I left mine a turn too far out once and had oil flowing down the front of the head just like a loose valve cover would give or if the cam bolt is not sealed properly...I have a picture of it if that helps...


http://i1179.photobucket.com/albums/x399/akwarian8/IMG-20120320-00062.jpg

 

[brwntom]

On the older trucks (not sure about later models) there is a peg that holds the timing belt tension spring as well as the timing marker in place...it is just below the pulley on the camshaft and to the right...if you pull it out the hole goes right through to the head and oil on the top of the head can leak out...

With enough pressure in the valve cover or if you have blow-by it will actually blow out the hole...if the peg is not fully tightened oil can leak through there...I left mine a turn too far out once and had oil flowing down the front of the head just like a loose valve cover would give or if the cam bolt is not sealed properly...I have a picture of it if that helps...


http://i1179.photobucket.com/albums/x399/akwarian8/IMG-20120320-00062.jpg

Thanks, Learned something new there. My buddy has an older truck that is leaking up front. Ill pass this along.

 

[Mark_88]

You're welcome...but also have him check the cam gear bolt...that can leak also and I found putting teflon tape around the threads stops that leak...any thread sealer will work as long as you don't use anti-seize

 

[naford]

Wouldn't a plugged PCV cause high pressure?

 

[Tedybear]

Wouldn't a plugged PCV cause high pressure?

Depends. If the engine has a lot of blow-by, what it can do is actually push the fumes and stuff out the vent filter. If that's plugged up? Ever seen a PCV valve pop out of the valve cover like a turkey pop up timer?

S-