George and Myron are right on the money. It may just be that the cam follower block is worn down to where it's not opening the points. If you want to know which one is faulty, unplug the harness and you will see three contacts. The center contact is common to both sets of trigger points. Check continuity between center and right while turning the engine over. Then do the same with center and left. Then you can remove the contact assembly and clean/tweak (bend) the fixed side of the contact(s) to provide more gap. If you shoot for a dwell of approximately 180 deg, you should be fine. The dwell and timing of the trigger points is not critical. Just remember that over time the cam follower blocks wear down and the opening gap lessens.