Rebuilding an EM pop bumper
Steps
- From above, remove the bumper cap (usually two small screws) and the bulb, then the two screws holding the bumper body to the playfield.
- From below, remove the two locknuts on the rod and ring, and unsolder (and unstaple) the lamp socket leads.
- Lift the body, skirt and rod and ring out from above. Clean the playfield under the body and wax it.
- Inspect the bakelite and steel armature links in the coil plunger; replace cracked ones.
- Inspect the rod and ring; replace it if the rods are loose or the threaded ends aren't square.
- Tighten or re-peen the coil stop; replace or re-stretch the plunger spring to the coil's length.
- Replace the coil sleeve (two screws hold the coil retainer). If the old sleeve won't slide out, the coil has been overheated; fit a new one.
- Clean the body, replace a cracked body or broken base, and fit a new skirt and a new lamp socket.
- Reassemble from above with any small nub on the skirt toward the top of the playfield. Fit the rod and ring locknuts snug only; over-tightening breaks the rods.
- Resolder the socket, then clean and adjust the spoon switch.
Systems
Related tips
- How an EM pop bumper works
- Making pop bumpers kick harder
- Cleaning and adjusting the pop bumper spoon switch
- Strengthening pop bumpers by removing coil windings
- Renew sleeves on flipper, pop bumper and sling coils
- Game resets but no playfield solenoid works
- Gottlieb pop bumper relay and score reel stuck on
- Converting an EM flipper or bumper coil to DC
Source: Repairing Electro-Mechanical (EM) Coin Operated Games to 1978, Part Two, Clay Harrell (pinrepair.com)