My number one piston exhaust lifter is running dry and noisey. I looked at all potential causes and still have the same issue. It just barely spits oil bubbles and not enough oil pushes our the rocker orifice. I checked the oil hole in the lifter cylinder and there is oil with pressure coming to the lifter. I replaced the lifter With a new one and primer it prior installation. Can not get the tap out of the way. Going crazy. Engine is a 302. Any help is much apretiated.
Whats your oil pressure gauge say, how much oil are you getting to the rest of the rocker arms on that side. Lobe on cam going bad ?
Put a straight edge across your rocker studs on that side and make sure that one isn't sticking out further than the others. If it is pulling out, it could cause the tapping.