Leaking valve covers

[Nero]

Alright so with my engine build I installed new valve cover gaskets.

I haven't even hit 100 miles yet and they're already weeping oil everywhere.

Is there some sort of ancient Chinese secret to making these suckers not leak? My valve covers are not bent or anything.

 

[hacked89]

Any chance you over tightened?

 

[DaveBen]

Put them on snug but NOT over tight. RTV them on if you don't need to get into the valve covers. BOTH sides of the gasket.

 

[The_Josh_Bear]

Only "secret" I found was having straight metal and re-tightening them after years of neglect. I don't know the spec but I remember it being in the inch-pound category, super light.

 

[Nero]

Any chance you over tightened?

This is highly possible as I was rushing getting it together. I'll re check it in the morning

 

[The_Josh_Bear]

Did you remember those wide triangle washers that spread the load at each bolt hole? If not, that'll do it.

Also if over-tightened the washers will bow and you'll want to flip them over when you go to re-tighten them so they aren't squishing the covers funny. (or put in a vice/hammer to straighten)

 

[Kdo58]

Cork or rubber?

 

[Nero]

Cork or rubber?

Rubber.

I'm pretty sure ive over tightened them.
I do have the triangle things on there too.

 

[Kdo58]

Tried rubber they leaked for me, corked worked for me. I put the right stuff on the valve cover side, no leaks for 6 months so far.

 

[IDIBRONCO]

With the rubber ones, you need to tighten them tighter than the recommended spec. I use my 1/4" drive air ratchet to tighten them down. It's rated at 30 lb/ft and I tighten them as tight as it will go. I don't use any sealant and they don't leak.

 

[MtnHaul]

With the rubber ones, you need to tighten them tighter than the recommended spec. I use my 1/4" drive air ratchet to tighten them down. It's rated at 30 lb/ft and I tighten them as tight as it will go. I don't use any sealant and they don't leak.

That echoes my experience a bit. Mostly I had a helluva time getting the back bolt or two tight enough on the passenger side. I switched to a cork gasket with a little High-Tack and so far so good, but I did also get more torque on the rearmost bolts. When I removed the old rubber gaskets there was no RTV and I'm guessing they had held for a long time because they were brittle and cracked easily.

And be sure to tighten them with the appropriate bolt sequence.

 

[Nero]

So they were a little tight. I loosened them all up and tightened them again, but not as tight. Only using a 1/4 ratchet so I imagine its not much.

Guess we'll see if it helps....

 

[Nero]

Annoyingly this is still an issue. Its less, but still weeping down my heads and all over my front diff.
Guess I need to get replacement gaskets again.

 

[yARIC008]

On mine, i put in new gaskets and RTV on both sides but not so much it squirts out all inside. I also then put cam lock washers on all the bolts and it hasn't leaked in years now. Make sure the covers are a straight as possible too/not bent.

 

[The_Josh_Bear]

Annoyingly this is still an issue. Its less, but still weeping down my heads and all over my front diff.
Guess I need to get replacement gaskets again.

They're basically brand new gaskets made of rubber. I doubt there is anything wrong with them, but rather with the rocker covers themselves. Unless they are cut/cracked somehow they would just re-form once the pressure is released.

IMHO the answer is pulling the covers and making them dead flat, flipping the washers upside-down and then torqueing to spec. That's how I cured my weepy covers years ago, still good to go. Maybe not perfect, but I'm not very particular about one little drip, either. Smoking manifolds, however, I do not enjoy!
Best bet for longevity is to smear a very thin layer of RTV black on both sides of the gasket. I didn't do that, but it'll work for sure.