Lend me you ears

That's how mine sounds. Like a sewing machine idling at 500 rpms.

This after a complete rebuild. My machinist refaced the rocker arms because they were grooved after 97,000 miles so I'm pretty confident I was getting true readings. I would assume the rocker faces were originally hardened so not sure how that will work out long term. 8000 miles on new engine. I should probably pull the rockers in the spring and see how they're holding up.