Gasket debate, Cork or Rubber

I had my valve covers off last night to re run my valves and noticed that the VC gaskets had som oil on them. I used the thicker 7/32 cork felpros with no sealant. The covers are moon cast alum covers. I know rubber holds well but since the covers are cast and I am not running any spreaders on them to distribut the pressure to seal them would it be better off to use the cork again with a thin bead of silicone on the VC side to take up any inconsistancies in the casting or clamping force. I didnt use sealer the first time because I knew I would have them back off to check the lifters. What has been your experience with sealing cast covers.

 

I like cork with a little sealer on the valve cover.

 

I always use the Ultraseal rubber gaskets with a skim of RTV on the cover side.
The only thing I see wrong with the cork ones is life expectancy. They tend to dry out and leak after awhile and rubber doesn't seem to do this.

 

It depends on the valve covers style as to if I use cork or rubber. Sometimes the rubber gaskets don't seem to fit well on older style valve covers. Cork works just fine but instead of using RTV, I usualy use this yellow 3m weatherstrip ahesive that is like contact cement.

 

I always use the rubber type, they normally dont tear if you have to take something apart, esp if your on the road at the time.

 

I don't use silicone on valve cover gaskets,
rubber or cork.
first time I pull a cover it invariably partialy seperates between the cover and gasket,
requiring a new gasket.
if I use permatex 2, the non hardening kind,
if by chance it does fail
I can most times clean it with laquer thinner, recoat with a thin film of sealer
and reuse the same gasket.
the only place I use silicone is at the ends of the intake manifold
instead of the neoprene end gaskets.

but that's just me.

 

cork is traditional. Rubber gaskets came along much later sometime in the 60's

I don't understand the use of gaskets AND silicone. If you need silicone to make the gaskets seal, you need new gaskets. IMHO

If you go through your valves every weekend at the track, the rubber ones make sense. I always had trouble with the new fangled rubber ones on stock tin covers so I personally don't like them.

I like to glue the cork to the valve cover and I wipe the gasket surface with Vasoline not as a sealer but as a mold release. The cork takes the irregular shape of the head casting and for me has always mated up perfectly to form a seal when R&Red. They don't last forever however.

I have a personal hangup about blue goo or any other color silicone. It has it's place but not on a valve cover gasket. IMHO

 

yup, black, if ya gotta use it..

same for those one piece blue pan gaskets
I don't care if they are the best sealing, most reusable gaskets in the world
I really don't want to see them on my motor.

 

What Engine are you working on ?

 

small block chevy, mid 70s heads, moon cast valve covers.

 

I like the rubber with the metal insert . It s easier to line the valve cover and bolts and get a better seat. No leakers yet.

 

Use our FelPro molded rubber with stainless steel innercore and crush stops, and multi-lipped sealing surfaces. These are used by all the race teams.
FelPro Part number 1628.
Summit has them, or any Performance shop selling FelPro.
http://store.summitracing.com/default.asp?target=partdetail.asp&part=FPP-1628&N=115+400101+308234&autoview=sku

 

Yup same here never had any problems with cork and yellow snot

 

Erik @ Partzfinder has them for $35.00, and he is a HAMB'r too!
http://www.partzfinder.com/Chevy_SB_FelPro_Silicone_Rubber_Valve_Cover_p/fel-1628.htm

 

cork with a thin layer of silicone on the vc side, treat the head side with a bit of oil or vasoline

 

Cork with black gorilla snot on the VC side. If it's a race car deal or something you have the covers off of a lot, a little grease on the head side of the gasket.

 

hard to tell in the picture..
are they blue?

or can you get them in black?

 

Our's are Blue.
http://www.federal-mogul.com/aftermarket/us/felpro_perf_valvecover.htm?Country=USA&NumIm=4

 

For hard to seal valve covers I like to use a cork gasket. First clean the head and cover surface with a solvent that doesnt not leave a a residue, carb cleaner or brake cleaner... make sure it's CLEAN ! then apply a thin bead of RTV silicone on the flange of the the valve cover and while this is drying or skinning up , apply a thicker bead of RTV on the raised bead of the head, allow this to dry and as this is happening, apply a small bead of RTV on cork gasket....then apply cork gasket to valve cover.....after 1/2 hour, with the gasket on the valve cover, position the valve cover on the head....install bolts and SNUG but not too much , you'll see RTV squeezing out where the gasket is meeting the bead of RTV.....DO NOT tighten ...for best results and no leaks let sit 24 hrs. This should form a good leak proof seal.... then after 24 hrs snug up tight. Takes time but if you're having a problem with leaking covers, this will work.

 

Thanks guys for all the good responses and opinions.

 

I saw a transmission pan one time sealed with white tub caulking.

I can tell you from what I saw that **** didn't work.


I use rubber ones. GLue them to the valve cover and wipe the engine side down with oil.

Works for me.