When installing copper head gasket is it best to use any kind of sealant on the gasket, or install it dry?
Thanks for the info.
I always have good experiences with the copper coat spray. Your local auto store will have it.
P.S. Don't put the head gasket on backwards! Look carefully at the shape of the block at the rear and match the gasket to it. Otherwise, the gasket will hang out at the front of the engine and, I believe, some of the small steam holes will be blocked by the gasket.
I've always done it dry and had good luck. Frankly, I'm not so sure the really important thing is using or not using sealant. I think the really important things are that everything is clean and properly torqued.
Jerry gives good advice on checking to be sure you don't have the gasket in backwards, which is easy to do and will block holes.
Always good to hear from the experts. Thanks guys!
A couple of coats of aluminum spray paint works well for a sealer and makes any future removal easier.
I only use sealant if I have a portion of the block which has eroded, such as around the rear of the block there is a large water passage and over the years seepage has caused some rust in that area. I put some sealant around the back side of that passage. If the block has been decked, that would not be necessary.
Copper gaskets removed, after miles on these motors, to compare.
One was sealed with aluminum spray paint prior to install, other left bare.
Sealing is what I do, CopperCoat spray or Alum spray paint, what ever is handy. Both sides of the gasket get a light complete cover spray coat.
From the AERA Engine Builders Association about copper head gaskets:
Sealants Required? Yes, some method of sealing is required if the engine will be running coolant or oil through the head gasket. I state it this way because many racing specific engines either A. do not run coolant or B. re-route the coolant and oil away from the head/block mating surfaces. Since most engines run coolant and oil through the head gaskets we’ll discuss head gasket sealants. Most importantly, you don’t need very much; second, don’t use silicone.. that about covers it. People get into trouble with leaking head gaskets when they use too much sealant, especially too much silicone. Since the block and head surfaces are flat, the potential leak paths are very small, even with a 100RA surface finish the peaks and valleys are only about .002”, which doesn’t require very much sealant to be fluid-tight. Head gasket dressings do not cure, therefore, as the head bolts are tightened the sealant ‘flows’ from the places it’s not needed (peaks) but remains in place to seal the leak paths (valleys). By contrast, silicone cures to form a layer that the cylinder head can sit on, never actually coming into contact with the head gasket (refer back to our discussion about metal-to-metal above). We recommend and use both KW Copper Coat and Hylomar in the aerosol cans, simply spray a light coat on both sides of the gasket, let it ‘tack up’ for a while (no less than 2 hours) and you’re ready to bolt the heads on.