yes, before you buy new lifters, if you feel like putting it all back together and maybe taking it apart again, go to the auto store and buy some liquid that frees stuck lifters, i think the stuff in the yellow bottle is the good stuff, it sounds like water inside when shacken its not the thick crap, it will unstick the problem lifter if thats the problem, if it doesn't work, you will have to buy new lifters. You did make sure your rockers are tightened correctly, 0 lash then 1/2 tp 3/4 turn more? if so, its a lifter problem.