https://www.pinballlife.com/williamsbally-pop-bumper-leaf-switch-assembly-populated.html
100 ohm resistor 1/2 watt
22uF 100v capacitor
1N4001 or 1N4004 diode
They are needed for a responsive pop on F14. This is why it is weak. I had the same issue.
Plenty of pics online for the wiring schematic