Quote Originally Posted by RhdDc2
Was the engine properly primed before starting? Doesn't take long for the soft babbet metal to wear on the bearings. Could be the cause. Do you have an oil pressure gauge?
no need to prime, dry starts are perfectly fine.

Only knocking noise generally from the head is the lost motion assemblies. How old is the head?

as far as head gasket, USE OEM, YOU CANT BEAT IT.