Anyone have valve cover sealing tips

MiniCJJ64

Well-known member
I have the aftermarket crome cover and I always have a hard time sealing it.
Also how good do the valve covers from classic inlines seal.
 
The CI cover probably seals a lot better. The after market chrome covers are thin and not very strait.


Make sure everything is very dry, and use sealer :)
 
Those little spreader thingies to disperse the load of the fastener help out as well. Had to use a couple on my evil-bay cover to make it hold right.
 
It takes me a while to figure things out, but occasionally I do. I'd like to review the gravity of this subject. If your PCV Valve is plugged, or you have excessive blowby, you may get leakage between the head and the gasket, but that's not too likely. Inside the cavity formed by the cover, oil is splashing everywhere. As such, it strikes the sides of the valve cover, and drains down to the top of the gasket. There, if the gasket has any upward curl, it pools and tries to follow the line of least resistance (as all fluids do). Therefore, a thin coat of gasket cement, sealer, or RTV applied to the top of the gasket will make sure the oil drips in, not out. No amount of torque will stop a leak from an improperly sealed gasket to cover area. A thin coating of RTV should do wonders. Do not overtighten. I know some gaskets say not to use sealers, but that will only work with perfectly straight, solid, hard valve covers. Maybe....
 
my advice: make sure you get a cork gasket, not a rubber one. rubber gaskets do not perform well with RTV.
that said, make sure the valve cover is straight and clean, and use RTV conservatively on both sides of the gasket
 
The Plankster Prankster":3pshk169 said:
my advice: make sure you get a cork gasket, not a rubber one. rubber gaskets do not perform well with RTV.
that said, make sure the valve cover is straight and clean, and use RTV conservatively on both sides of the gasket

I'm not sure what you mean by this. Rubber gaskets perform fine w/ RTV.

Using RTV or any other adhesive sucessfully is 100% dependent on process. The surfaces must be dry and oil free - the adhesive must be applied properly (not too thick) and the two surfaces must be place in contact firmly and securely for a long enough period of time to let the adhesive cure.

You can seal just about anything with RTV if you actually prep the surface correctly and are patient enough to give it 24 hours to cure.

Rubber gaskets are no exception.
 
I always glue the gasket to the valve cover wether its cork or rubber using 3m (or its equivalent) weather strip adhesive.

Then use 20 or so clothes pins to clamp it in place until its dry.

Later,

Doug
 
I always like to make sure that the flange is flat and that the bolt holes ahve not been pushed in. I glue the gasket to the valve cover.

Then I use some of the metal SBC valve cover hold down tabs. You can usually get four or five of them on (can't remember).

mrg-9817_w.jpg


Make sure you don't overtighten.
 
I have the cheap (approx 12.00) from e-bay chrome vc from e-bay and a chrome cover from Summit (approx 35.00).

The one from Summit seals no problem the other one leaked no matter what I used.

I've used RTV to seal the rubber gasket to the cover and the cork gasket and used hold down tabs.

Get the one from Summit or the aluminum vc from Mike.

Bob
 
I had problems sealing my chrome cover when i first got it. I ended up buying 2 cork gaskets. I 3m'd one to the valve cover and one to the head and let them set up over night. Put them together the next day...No more leaks
 
Has anybody used the chrome vc from Falcon Enterprises? They always seem to carry good stuff.

Autozone also carries a chrome valve cover, it is the Spectre brand, and you have to special order it.

When I seal things with RTV, I always install the bolts and tighten them just a quarter of a turn, let the RTV dry for a few hours, and then torque them. :thumbup:
 
8) part of the problem is the chrome itself. using chrome valve covers, thermostat housings, etc. tend to be hit or miss when you try to seal them up. start by taking some steel wool and scuffing the gasket surface. use a fairly course steel wool. then glue the gasket to the valve cover with 3M weather strip adhesive. i prefer using rubber gaskets, but cork can be used as well. some of the other suggestions like making sure the valve cover bolt holes are flat as well as the rest of the gasket surface, and use the items indicated by mustang 6 as well to distribute the bolt torque.

the best way to go though is to use the cast aluminum valve from classic inlines.
 
sand the gasket surface on the VC, that helps alot, as the chrome is slippery and not very good at keeping the silicone or gasket maker compound stay.
 
:D Afriend of mine had problems trying to get a chrome thermostat housing to seal.
We finally had to use a new flat lile on the sealing surface to clean off the plating and get the surface flat.
Leo
 
Use either Edelbrock's Gasgachinch sealer on the gasket, or better yet don't use a gasket - there's some stuff you can get at local parts places, I think Loctite makes it...runs about 10-15 bucks for a skinny can - and for the life of me I can't recall the name of it. Arrgh.
 
Just to reinforce my main point. The oil leaks at the top of the valve cover gasket. That's what must seal. The oil leaks around the bottom only if the oil isn't draining back correctly.

I did have some stuff from Permatex, IIRC, "Formagasket", which looked like pink tapioca; and set up into a rubbery gasket without sticking, once pressure was applied. Haven't seen it in years.

As far as VCs, the cast types retain their shapes; the stampings will eventually deform.
 
I would NEVER use any sealant of any kind between the gasket and the head. It's not necessary and makes it a pain to remove the cover later. I have one of the ClassicInlines alum cover using a rubber gasket with rtv silicone between the cover and the gasket. Seals fine, no problem. The thick aluminum flange is nice and straight and won't bend or warp like the thin metal covers, hence a nice seal. Just my 2 cents. :wink:
 
:D As I said earlier,another little trick for good sealing on a valve cover.
Junk the bolts,and use studs and Nyloc(R) nuts.Works like a champ.
Its a set and forget deal.
Leo
 
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