Tractor Repair: 1953 Ford Jubilee, vacuum leak, 1953 ford jubilee

Question
After using the tractor for about an hour mowing the pasture, the engine losses power and stalls out. Restarting
the ford, it will run a few minutes and die again and again.
I have checked the fuel line, seems to flow freely. Took the carb off and cleaned it. What next can I try? And could there be a vacuum leak(how does the fuel/air get into the engine block)?

Answer
 Hello,

   Even though you checked the fuel flow from the fuel line, make sure there isn't something in the fuel tank that is sometimes blocking the outlet.  The flow from the tank to the carburetor has to be full flow, a dribble is not enough.  When it dies, remove the fuel cap and see if you hear a vacuum being released.  If so, the cap is not venting properly.  When it starts to die, pull the choke out and see if that helps.  If so, then it is definitely starving for fuel.  If you had a vacuum leak, I doubt that it would run OK for an hour and then stop.  To be sure though, check the carburetor and manifold mounting bolts to be sure they're all tight.  There's also the possibility that when the engine gets hot, there's an ignition problem.  Check to see if it loses spark at the spark plugs when it dies.  If so, the coil or condenser could be bad.

                    Good luck,

                        Arnie