Just wanted to check a few details on the engine.
in general you need to determine the problem area, so have a spark tester and a can of carb spray handy.
Run it again until it acts up, then take off the air filter and try to start while spraying the carb spray directly into the carb, see if it starts and dies. If it does, loosen the gascap and try it again and see if it keeps running, if it does, then that was the problem.
Next, test for spark, if you have no spark, then let us know before replacing the coil.