Tractor Repair: tractor starts hard, check the flow, full stream

Question
1950 something 350 International tractor won't always start.  When it does start, runs a short time and quits.  Replaced points, condensor, resistor, spark plugs, fuel filter.  Before it quits, it runs rough.  If I bypass resistor it will run a little bit longer before it quits.

Answer
 Check if there is spark when it won't start or when the engine quits.  If not, then you know for sure it is an ignition problem.  If there is still spark, it is a fuel problem.  If it is an ignition problem, it's possible that the coil quits working when it gets hot.  If it is a fuel problem, check the flow of fuel from the tank and if there is a restriction, clean out the tank outlet.  The fuel line should run full stream, not just a little dribble.