[Bruce Compton, Canada]

Randy : Is there a pattern or cycle the " comes and goes" noise , or is it random? I had a similar cycling noise in a "Y" block and it was an out of round wrist pin rotating in the piston. If its a random occuring noise, I'd suspect a sticking valve, or posibly too much end play in the camshaft if the engine was assembled with the wrong set of timing gears ( 8BA type) that thrust the cam to the front of the engine. You may want to run the engine for a few minutes with the belts off as the noise that the generator, fan, belts and pumps are creating will mask the noise you are trying to find, especially at higher RPMs. By doing this you will also eliminate any noise sources from these components. Good luck : Bruce