It sounds like you're carb needs an insulator between it and the intake manifold or at least a sheetmetal heatshield. Those aluminum bodied AFB style carbs are prone to percolating when heat is transferred.

As far as a fuel pump, your problem is at idle, it doesn't take much to feed the motor at that time. It's a problem with the carb getting too hot or fuel mixture too lean, not a volume issue.