Power Piston – Removal, Installation & How it Works:
Rochester 1 Barrel Frozen Power Piston – How To Remove
When a 1 barrel carburetor sits for any length of time (years), the power piston will most likely end up frozen in the carburetor. Penetration oil probably won’t get it out, but heat will.
Clamp the carburetor in a vise, apply heat to the ouside of the power piston well. As you heat gently wiggle the power piston. Once you get the carburetor hot enough, the piston will start to move and you should them be able to pull it out.
Buff the power piston which is brass to get the dirt and grime off. Polish the inside of the piston well with crocus cloth. You can also use silicon spray lubricant and a brush to clean the well. The point here is that the power piston should move in and out freely. Only vacuum pulls the piston in.