Jim,

Dwell is the number of degrees the distributor cam rotates while the points are closed..the coil is saturaing or 'charging'. Although this is relavent when the engine is running, I think you need to stick the dwell concern on the back burner and get back to a primitive hands on approach, gapping with a feeler gauge, that's the starting point.

A shorted condenser can cause this problem. You need to use your meter or tester and verify proper voltage all the way to the points.

Stuart