Hey FriedGreenTmater
When I ran the 20w50, I had the tapping noise. Now I run 10W40 and the tapping has gone away. Nothing to hide there. As far as the chain slap, I was told it is common on these engines, especially if the engine is original with less than 30,000 and has never been rebuilt. This came from a group of guys in their 70's who use to work in a shop back in the 60s and 70s.
I know, everyone is always out to say there is no way this truck has less than 30,000. But think about it, it is a local tow truck that spent most of its life sitting at a gas station, used occasionally whenever they needed a tow.
I have pulled the carb to rebuild and was amazed how clean the intake manifold throat was. When I pulled the valve covers off to replace the leaking gaskets, the inside was almost spotless. You could still see the orange dots on each rocker left from inspection at the factory. I could list many more examples from the rest of the truck but believe me; I have a 1966 truck with less than 30,000 miles.
Thanks again for the info.
