I'm rebuilding a rochester B carburetor. The power piston is stuck in it's hole in the float bowl cover. Is this intentional or is it just stuck and I need to free it up?I tapped it with a screwdriver handle and gave it a small tug with pliers but it doesn't budge. I sprayed it with carb cleaner and let it soak. Does this thing have to move or is it possible it was set stationary at the factory?---Jack