Cork Valve cover Gasket Installlation .... to use sealant or not ???

[Bill Balkie 24172]

Hello ,
   I would like to get some advice on installing Valve cover gaskets on a 472 engine .I have removed my valve covers  and cleaned the surface of the heads to bare cast iron . There is not a trace of old cork gasket or sealer on the surface . i can say the same  for the valve cover itself . I purchased a set of Fel -Pro cork Gaskets . i am a machinist/toolmaker by trade . When i lay my valve covers on a granite surface plate  they have a crown    with the center touching the the table and the ends in the air  about  .075  . I am not 100% sure if thats a good thing or not .  My question is to use sealant or not and if the answer is to use sealant what is the best kind to use? Should the sealant go on both sides ? Is there a procedure that works the best ?

    Thank You ,
           Bill 

[hornetball]

I don't use any sealant.  My main concern is to make sure the bolt holes are flat (I flatten them with a hammer and dolly).  I'm then fastidious about torquing to the FSM value in steps using a star pattern.  I don't have leaks doing it this way.

Not sure about what you observed regarding overall valve cover flatness as I've never checked that.  But I think the valve covers are flimsy enough that they will flatten out when bolted down.

[INTMD8]

Agreed with above ^

[TJ Hopland]

If they seem to fit nice and stay in place you should be fine without sealant.   If they don't want to stay in place something thin like hitach or a very thin layer of your favorite rtv should be enough to hold them in place.   Typically you would put that sealant on the valve cover side. 

[Scot Minesinger]

agree with Hornetball

[Bill Balkie 24172]

Hello ,
    Thank you everyone for your input . I will try it without sealant the worst that can happen is they leak . I will use the star method of tightening the the covers .


      Bill

[novetti]

If it's all good and don't need a reason to remove the valve covers anytime soon I like to use a flexible type sealant at the cover side only, not in the casting side.

The cover being stamped metal has more chance of being distorted than the casting from the heads, therefore a bit of goop there doesn't hurt.

[The Tassie Devil(le)]

What I do is use Loctite 5900 on the cover and place the gasket in place, and loosely screw down to let the RVT set, then remove and place another bead of RVT on the gasket, and then screw down.   Never had any leaks.

With an engine with Adjustable Rockers, where the covers have to come off, I RVT the gasket to the covers, then smear a small amount of grease on the gasket so that it doesn't stick to the head, and therefore isn't destroyed when removing for adjustment.

Bruce.

PS.   But, who these days has adjustable rocker arms.

["Cadillac Kid" Greg Surfas 15364]

With a stock motor I typically use a line of Yellow Weatherstrip adhesive on the covers and then turning the covers upside down, place the gasket in place, locating it by using the 1/4 in cover bolts dropped through the gasket holes, through the cover holes and let that set for a few minutes.
That way when I install the covers, the gaskets stay in place.
On my hot rod motors I typically use the rubber gaskets, held in place to the covers with the Weather strip adhesive.  I have been able to remove and replace the covers multiple times with out tearing the gaskets or having oil leaks.  A good deal of the Technique is in tightening the cover bolts evenly and not too tight.
Greg Surfas

[SixDucks]

I do mine somewhat different than most. The first and most important requirement is valve covers that are not bent from having been over torqued.  I always use cork gaskets over rubber. My method differs from most in that I apply a thin layer of RTV to the entire gasket. By thin, I mean just as one would butter a piece of toast. I allow the RTV to completely cure. Afterwards I again apply a very small dab of RTV to the corners and middle of the gasket to secure the gaskets to the covers. This method allows the gaskets to always stay pliable, never dry out, and remain reusable without leaking or any clean up. By doing this the cork gaskets acts as a rubber gasket and will not dry and crumble like the rubber gaskets do. My drag car had the same gaskets for over ten years and were removed countless times for valvetrain maintenance Never once did I have a leak.

Terry

[Jason Edge]

On the 390/429's valve covers I have installed many times over the years, I only use the thick cork & rubber gaskets and never use sealant. The main thing is to make sure the valve cover is straight. I've parted out 52 1963/64's and would say 90% of the valve covers I have removed have been over-tightened causing the mounting lip to bend down. People over-tighten the covers the 1st time, which leads to more and more over-tightening during subsequent installs as they try to compensate for the existing bend. I will take the valve cover and straight edge block of wood and a 5 lb hammer and bang the lip back out straight before reinstalling or cleaning & painting. The 63's 64's are torqued down to 25 inch lbs... or JUST OVER 2 Ft lbs! I have found making sure the cover is straight, surfaces are clean, using a thick cork gasket, and torquing to spec (25 inch lbs), and re-torquing once engine has been run, is all that is needed.

[wrench]

Yeah, I don’t know if rubber gaskets are available for these things, but anyway, on valve cover gaskets in general I make sure the surfaces are straight and clean, then I spray Hi-tack on both sides of the gasket, assemble to valve cover then assemble to engine, snug the bolts, then torque the bolts in cross pattern as others have described.

https://www.jbtools.com/permatex-80065-hi-tack-spray-a-gasket/

[cadillac ken]

I've always used a bit of the old Permatex black flexible stuff, I think it's 2B. Just a little to seal up a bit better than the plain cork gasket.  I seal the gasket to the valve cover and the head.  Just my method.  No leaks.

[cadman56]

It didn't matter what I used to seal these.  Until I started using Lacquer Thinner or Brake Kleen to clan the heads and covers.  The slightest residue of oil will eventually cause a leak.  Then you can choose your poson for sealant.

And the covers must be totally flat against its mating surface.

[Bill Balkie 24172]

I do mine somewhat different than most. The first and most important requirement is valve covers that are not bent from having been over torqued.  I always use cork gaskets over rubber. My method differs from most in that I apply a thin layer of RTV to the entire gasket. By thin, I mean just as one would butter a piece of toast. I allow the RTV to completely cure. Afterwards I again apply a very small dab of RTV to the corners and middle of the gasket to secure the gaskets to the covers. This method allows the gaskets to always stay pliable, never dry out, and remain reusable without leaking or any clean up. By doing this the cork gaskets acts as a rubber gasket and will not dry and crumble like the rubber gaskets do. My drag car had the same gaskets for over ten years and were removed countless times for valvetrain maintenance Never once did I have a leak.

Terry Hello Terry,
     Do you put the RTV on one side of the Gasket and let it cure and then do the other side ?   By curing do you mean 24 hours ? One side and then the other ?  One last question what type of RTV do you use ?
  I guess the trick is to apply the RTV as consistent as possible .  I like your
Method and I am going to try it .
  Bill 

[SixDucks]

Hi Bill,

I coat all of the surface of the gasket with RED high temp RTV and allow the RTV to completely cure. 24 hours is likely more than enough. By doing this the cork gaskets keep there crush and do not absorb any oil.
I do this because with age and heat, rubber gaskets can become hard and brittle. Oftentimes this results in gasket material in the head when scraping the gaskets off the surface.
I learned this because the Oldsmobile engines have poor drain holes in the ends of the cylinder heads. The drainage issue becomes worse when combined with a high volume/high pressure oil pump and high RPM.

Terry

[76eldo]

Valve covers are usually warped which creates the problem.  I am sure you know how to tell and can make the necessary corrections if your valve covers are bent.

A little of this stuff is what I have been using:

https://www.walmart.com/ip/PERMATEX-Aviation-Form-A-Gasket-Sealant/19279233?wmlspartner=wlpa&selectedSellerId=1131&adid=22222222227000000000&wl0=&wl1=g&wl2=c&wl3=42423897272&wl4=pla-51320962143&wl5=9007206&wl6=&wl7=&wl8=&wl9=pla&wl10=112562428&wl11=online&wl12=19279233&veh=sem&gclid=Cj0KCQjwyPbzBRDsARIsAFh15JbPqwh7fHlytjPmm3DaSw-zKctAHyxDZrZHaFQDoCZPWHZyQmf1ehYaAtwxEALw_wcB

It stays pliable but will stick the gasket in place while you are installing the covers.  Not thick, just a coating.

Brian

[walt chomosh #23510]

Hi guys!
I had been struggling with valve cover gasket leaks for years (including Harley Davidson Panhead covers) until a friend who was building circle track motors for local racers. He told me to try "the Right Stuff" (Permatex product)and I did....problem solved!....walt...tulsa,ok....(refrigerate the unused portion and it will be good years later!)

[ratpin]

Yesterday I refurbished my valve covers for the 60 coupe. I observed many of the issues Ive read about them an developed the technique I used from others here. I have not put them back on the car yet, but below are some pictures of what i did. My car had extremely bad oil leaks for years judging by the 1/2-3/4 sludge buildup covering both sides of the lower block. Literally 5 lbs of old layers of crusted oil.

To get the covers to properly seat I shaved 3/32” off the lip in the lower area where the head keeps it from sealing with the thinner cork gasket. I cleaned, straightened, blasted and painted the covers while they were off.