I recently bought a 79 Scout II w/ a 345. It is the coolest vehicle I have ever owned hands down but the engine makes a noticeable tap when I let off the gas and when it is warming up. It seems to completely go away when the engine is warmed up. I have been told so many different things that I don't know what to believe - bad lifters, worn cams, valves, and even to use 15W oil. There is 125,ooo miles on the engine. Has anybody else had the same problem? Any help would be appreciated.