Pulled the timing gear cover (and of course, the oil pan -- Chevy engineers didn't do us any favors with those bottom two bolts feeding in from inside the oil pan). Nylon cam gear was shredded. No surprise there, but when I shined a light into the bottom end... well look at that: Rebuilder's marks, labeling the piston rods.
I always suspected the engine had been rebuilt in the past -- it just ran too solid for a 60-year-old factory motor.
Next step: Pulling the valve assembly and checking for bent pushrods. If they are all fine, my plan is to replace the cam gear (aluminum, no "plastic"!) and then check engine compression.
I don't want to make work for myself by rebuilding an engine that's been already rebuilt and was running perfectly before the cam gear lost its teeth.
Rick
