Ok, so this thread is 7 years old, but this comment here is exactly what I'm curious about:

"Mine sticks and needs a bang on top to get it moving"

Any idea what is causing this or what can be done to sort it out once and for all? Mine sticks too. Not always, but maybe every third game. No rhyme or reason that I've found so far. It all looks fine when I took it out. All screws are in place on both the plate to wood and motor to plate. Wiring connector is fine and bulb comes on reliably every single time. The little disc just doesn't always get rotating when turned on. A light tap on the left side gets it going though, every single time without fail.

Weak motor? Replace it and done like dinner?

Didn’t see the reply here until now. Good call on the LED bulb. I found the same solution to my sticking rotating light. I took it one step further and installed the “mini” version of the 1156 base bulb and it works perfectly now. I used to need to tap on the backbox at least every other game and I haven’t needed to do that a single time since putting the correct bulb in. Probably 1,000 games in that time. Easy fix… just had to read the manual closely!! D’oh!!

I kept that bulb incandescent on my game, however, I think the 1156 bulbs I already had were from/for my car. You can buy those kinds of bulbs at your local automotive parts place as they are used in taillights and other places on vehicles.

There are a few different parts that work in both cars and pinball machines. And not that I don't want to support the dedicated vendors, but the prices can be pretty crazy if you buy the same item from one hobby versus another.

These look familiar?

https://store.delorean.com/105859-lamp-socket-assy-black.html

How about these?

https://www.marcospecialties.com/pinball-parts/24-8767

$1 versus $10? No thanks, lol.