Noise under valve cover
 

Took my '64 Camino out for a spin today.Just as I was turning into the laneway heard a squeaky sound coming from under the hood.At first I thought it was just a noisy belt or pulley because that's what it sounded like.Noise is coming from under valve cover.Engine is a 327.Oil pressure is good 40-45 lbs.at idle and 60-65 as it's reved up.Over the weekend I'll pull off the a/c compressor and pull the valve cover.Any ideas of what it might be?Thanks,Bill.

could be a rocker arm/ ball squeak. back in another time we would put some
GM posi additive (the whale oil stuff) in the oil and problem cured.

It could also be a lifter failing. Should be researched immediately to avoid ruining the cam if in fact a lifter is failing/has failed

Wouldn't a bad lifter make a tapping noise?Mine is a chirping sound.

Lifter stuck in the bore not rotating or rocker arm ball squeak both possible. I would not run the engine anymore then I needed to. Good luck.

take a video with the valve cover off and engine running.we can all teach our illiterate, unmechanical children. Thanks

Noise under valve cover
 

I had the same problem with a 1966 327/300hp Vette engine. The stock valve covers were re-installed upside down after new gaskets. Stock valve covers have a -O- stamped on the flange in the center of the valve cover. This stamped side needs to be installed toward the intake manifold, as the valve covers are not symmetrical. I saw evidence of the pushrod side of the rocker arms rubbing against the valve covers. I hope this solves your problem.