Did you check for oil in the points compartment Bob? There is a little plastic plunger that extends through into the crankcase - one end of it runs on a cam on the crankshaft, and the other end opens and closes the points. When the engine gets old the plastic plunger wears on its outside diameter, and leaks sump oil into the points compartment. If enough oil gets in there, it can get in the points and stop the music. A new plunger may fix it, but if not, the hole between crankcase and points compartment has to be reamed out and bushed. Not worth doing, a less-worn cylinder/crankcase isn't that hard to find.
