A feature timed by a delay relay that carries a small lamp acts erratically.

EM delay relay with a lamp on it misbehaves

Cause: The lamp is a #455 flasher used as a timer: it lights, then opens a second or two later, releasing the relay. Flashers vary, and one that is slow to light or stays on too long upsets the timing.

Checks

• Look on the cabinet floor relays for a socket with a small bulb, often on a relay named as a delay.

Fix

• Try two or three different #455 bulbs until the relay times correctly.

Systems

• Electro-mechanical

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Source: Pinball Machine Care & Maintenance, Bernard B. Kamoroff (Bell Springs Pinball Alley)