dashpot on Hy-Drive carb needs help

[steve3050]

I have a 53 Plymouth Hy-Drive car. I had the carb rebuilt about 2 years ago but did not have the car ready for any driving for some time. The dashpot is part of the carb housing, with no wiring involved. It does not prevent stalling when the throttle is opened when in gear, then let off. This is with a warmed up engine. It still stalls although the adjusting screw was turned out. I removed the top of the carb and found all was clean in there, and the leather plunger from the dashpot looked new from the rebuild. The only thing I found was that the dashpot linkage seemed slightly bent and was hanging up. So I freed that. It still does not work any better. It seems that the downward movement of the plunger us supposed to slow the shutting of the throttle. What causes the plunger to move upward in the first place?

[Ulu]

Typically, a spring raises the throttle if vacuum falls too low, to prevent a stall. The spring may be weak.