The head gasket(s) are sandwiched between the head(s) and the block. They seal up the combustion chamber, cooling system and oil system.
On many engines its quite a big job to remove the head(s) when the gasket needs to be replaced. And it is critical that the surface of the head(s) and the block are checked for flatness and if necessary be machined flat!
On many engines its quite a big job to remove the head(s) when the gasket needs to be replaced. And it is critical that the surface of the head(s) and the block are checked for flatness and if necessary be machined flat!