the best way to figure out what's wrong is to actually DIAGNOSE it.
1, it helps us to know 2 cyl or 4. the 4 have a very basic fuel system.. the 3 are much mroe complicated with a pump, different routing and a cantankerous carb.
at moment of death and during restart attempts when it won't start. does it have spark? good spark?
if yes.. move on to fuel.. specifically fuel flow.. they won't run with an empty carb.
if it don't have spark.. hotwire coil.. if nada still.. check points, feel coil.. .. use ohm meter on connections with power unhooked to look for shorts, and if points open and close. check continuity on secondary and primary of coil.. check dizzy feed thur insulator.. make sure condensor is not shorting ( rare ) but happens.