By "dieseling", he means does it run on when the ignition is turned off? Often engines that ping will also run on, but 216s are unlikely to ping because of their low compression. Your carb could be percolating if you don't have a phenolic spacer between it and the manifold. A heat riser sticking in the warm up position can also cause percolation. You might try advancing the timing a bit to see if that helps the cooling, as insufficient advance often causes overheating.
