Hi Tom. Thanks for the info. I didn't consider the possibility of worn valves/valve seats, but was thinking along the same line concerning the adjusting cap nuts/rocker arms.

If the valves/valve seats are worn in the one position and assuming there is a valve rotator device, can maintaining proper, or even loose, clearances eventually correct this?

I'll recheck the clearances soon, and also take a close look at all the external parts. BTW, the car ran well before the valve adjustment and continues to do so along with an easier start. All the best!

Jerry