Quoted from sraasch:
beatnik-filmstar: Can you elaborate on the bit about replacing the metal coil sleeve? Your link to that old thread didn't post.
My mistake. Forgot to paste it in.
With regards to the issue that I was having - I had taken the bakelite plate off the stepper, cleaned it up, lubed it, etc. Pulled springs, made sure things werent gummed up and put it back together. Things seemed to work by hand just fine, but the stepped wasn't advancing right. It would go from player 1 to 2 just fine, but then not be strong enough to go from 2 to 3 or 3 to 4. Replacing the 40 year old metal sleeve did the trick.
Quite possibly not related (I'm just some guy that got a single EM up and running a few months ago.) but... you mention that the coil moves slightly, but not enough to move the actuator.
The final issue I had involved a score reel that wasn't working right. The coil for it would move slightly, but not pull in the arm to ratchet the wheel up. Caught the behaviour with some slo mo on my phone.
Turned out to be a switch on the 100 point relay that wasn't clean enough. Wild ass guess, but maybe check the switch that send the signal to the stepper telling it to advance? And as I write that, I see belbs316 saying something similar, as well as telling you where it is. Check that video - if that looks like the behavior you're seeing, I'd bet that belbs316 has pointed you in the right direction.