the 'pin' in the cap is fixed, the spring tab on top the rotor keeps a pressure on that pin, doesn't hurt to pull the rotor contact up a bit to insure it's pressing firmly
"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir "When we tug a single thing on an old truck, we find it falls off" ~ me Some TF series details & TF heater pics