05-12-2019, 11:24 PM
In my experience if the block and head faces are perfectly flat ( many blocks are low in the centre ) and you have water ways that are in good condition a smear of grease will usually suffice....certainly with copper asbestos gaskets, although some doubt exists with modern materials as I have discussed elsewhere here. However most times we are not dealing with perfect components and as a result water often seeps into the bores, especially on lightly used cars. I think that with regular (more than once a week) use a small amount of water seepage gets burnt off before it causes damage to the bores and valve seats, eventually the gasket seems to seal, probably from corrosion around the water ways and carbon build up on the flame ring. I believe it may be sensible in many cases to use a sealant such as described by Alan, Steve and others, but there appear to be issues with choosing the right sealant and quantity applied, too thick and it is blown out by compression exaggerating the problem. As I have said before at one time all I ever used was a thin smear of grease, but with the modern gasket materials I have tried a few solutions and the jury is still out on which is completely reliable. Some here still swear by coating the gasket Aluminium paint and I have seen this used successfully.
Black Art Enthusiast