Chevrolet: valves and lifters adj., crate motor, lifters

Question
i have a 383 crate motor and all of a sudden the back driver side started tapping real loud ,tried adjusting but did not help.whats next? thx

Answer
Randy  what do you mean you adj. it and it will still tap.  I wonder if the tappet stud is pulling up and out, if hyd. lifters  you adj. by loosen one at a time till it clacks than go back in till it stops than go in 1/2 to 3/4 of a turn more-go slow as it can cause the engine to stall.  try that. I hope that the stud. is not pulling loose on you.