It soundslike you don't have the distributor shaft engaged in toh oli pump, or the tang on the bottom of the distributir shaft has broken off. DO NOT continue toi run the engine until you find the source of the problem- - - - -the rod and main bearings won't last long without oil pressure! Pull the dizzy back out, and inspect the bottom of the shaft and the slot in the pump drive for damage. When you reinstall it, be sure the shafts mesh. If you're dealing with a 216 or 235, it's possible for the distributor to be installed too high on the clamp ring, letting the gear mesh and the engine run, without turning the oil pump. You can spin the pump with a big screwdriver blade clamped into a 1/2" drill motor with the distributor removed (clockwise) and oil pressure should build up.
Jerry

Last edited by Hotrod Lincoln; 07/11/2010 6:24 PM.
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