20 replies to this topic

[dklawson]

Can't say I'm crazy about the Silicon type gaskets especially when fitted between machined cast parts and pressed sheet metal bits, they just can't conform to the irregularities like cork will, and when you try to tighten them down that tad more, they oooze out over time. Cork doesn't look as 'bling' but time prroven over and over.

 

I don't follow that.  The silicone gaskets are softer than cork and will conform to irregular surfaces more than the stiffer cork.  However, if you have distorted surfaces to seal (such as a warped valve cover or tappet covers) and you do not bond the seals as in my method above, then silicone seals will ooze out as you say when pressure is increased.  The method I suggested allows the gasket to be installed perfectly flat against one surface with the RTV on the other surface to account for and compensate for for the surface irregularities of the mating part.  The method works for both cork and silicone seals so you can go for bling or no-bling.  This bonding method and grease on the head allow a valve cover to be installed and removed multiple times without damage to the seal.

[Spider]

 

Can't say I'm crazy about the Silicon type gaskets especially when fitted between machined cast parts and pressed sheet metal bits, they just can't conform to the irregularities like cork will, and when you try to tighten them down that tad more, they oooze out over time. Cork doesn't look as 'bling' but time prroven over and over.

 

I don't follow that.  The silicone gaskets are softer than cork and will conform to irregular surfaces more than the stiffer cork.  However, if you have distorted surfaces to seal (such as a warped valve cover or tappet covers) and you do not bond the seals as in my method above, then silicone seals will ooze out as you say when pressure is increased.  The method I suggested allows the gasket to be installed perfectly flat against one surface with the RTV on the other surface to account for and compensate for for the surface irregularities of the mating part.  The method works for both cork and silicone seals so you can go for bling or no-bling.  This bonding method and grease on the head allow a valve cover to be installed and removed multiple times without damage to the seal.

 

 

Hey Doug ;)  fair enough mate.  Maybe the silicon gasket you are able to get are softer than the ones we get?  Ours, Red in colour, are a bit firm on the feel. I'm only going from my own experience here. As you do, I alos adhere the gasket to the rocker cove, even the cork ones.

[Curley]

I'd been using the original cork type for some time on the basis that a) they're cheap b) they're original c) cork is very good at sealing irregular surfaces. But I've found that taking the rocker cover off more than a couple of time and I start to see signs of oil seepage. 

 

I was unsure the silicone would be worth paying 4 or 5 times more for but after fitting it (NOTE: Do as dkwalson suggest and fit the gasket to the rocker cover with RVC sealer) I've not had any problems; I no longer feel the urgent need to have 2 or 3 of them at hand 'just in case'.

 

I'd say this is one of those 'mods' that is worth spending the money on - If you need a rocker gasket that is.

Edited by Curley, 23 November 2014 - 12:36 AM.

[Jared Mk3]

I keep going back and forth between the two.

[dklawson]

At this time I have cork on the Mini and Spitfire and silicone on our GT6.  If you install the gasket using the method I proposed, either gasket material will work well.  

 

If original appearance is important to you, buy cork.  It probably costs less and with the savings you can buy a spare gasket for future use.  Store the spare gasket in a sealed bag in a cool dark place so it is not petrified when you need it years from now.

[Spider]

I keep going back and forth between the two.

 

Buy one of each!