Sticking vacuum piston plate

Quick update.... I pulled apart another Carter carb that I had stashed away and used the vacuum piston from that carb. It fits fine and all seems to move well. I noticed that the older one (that fits) has a Carter stamp in it and the other one didn’t. Apparently that piston hasn’t worked since I installed that rebuilt carb several years ago. My money says that the piston was stuck in the down position which allowed the car to idle well but probably suffered during acceleration. I look forward to my next drive. Right now I’m waiting for shipment of a new fuel line (pump to carb). I noticed that the old one had rust inside and was sending small bits of debris into my cleaned carb bowl. I’ve had a heck of a time finding a good match on a new fuel line but finally ordered one last night. I may get impatient and clean the old fuel line for temporary use.