If you're unsure what to do, a good place to start is pinrepair:

http://www.pinrepair.com/em/index2.htm#steps

search for "Gottlieb's AS Relay (the Miniature Stepper)"

shiny with no grease is how I like the steppers. I wouldn't disassemble anything yet. Someone with your schematic will chime in and get you going. it's probably a dirty relay that fires that match stepper. Maybe a dirty switch in the 10 point relay. But I'm guessing.

The relay quoted is your 'F' relay or '00 to 90 - Unit Relay' in the back box. This is likely not stepping correctly when triggered by 10 point contacts.

Post a few pics please

So when you actuate the armature plate with your thumb, nothing happens when you release the plate? It doesn't snap back? Or, it snaps back but the gear and wipers don't move?

Personally, the way I deal with those, which will make some cringe probably.. I use alcohol and 600 grit paper and just shine the board up. I hit the contacts as well. Then I put a thin layer of pbr grease over the whole board. I use qtips and alcohol on the gears making sure they are clean. Then I lightly grease them as well with pbr grease. Actuating the armature plate quickly, it should rotate. Work it a few rotations, and if it doesn't loosen up, bend the contact arm spring to lessen the pressure until it rotates freely.

Also make sure those two switches aren't riding the alternating cam too hard - that can cause a lot of drag on the unit. You can try to back off on the blade tension, or just loosen the switch screws for a quick test.

8 loops... you're compensating for some drag in the system. Try loosening up the switch or remove the rotors and test by hand. Something is exerting too much resistance.

Definitely order a new spring, just in case you find the drag. Some of the nylon parts are OOS at PBR.

Have you done tests like these? -

With the AS relay removed from the pin:

1) Actuate the armature with your finger and get a sense of how bound up it is, then

2) relieve all pressure on the black cam by unscrewing the switch stack (let it dangle out of the way). Actuate the armature a few more times... is it any better?

3) if not, remove the wipers from the ratchet shaft. Actuate the armature a few more times... is it any better?

I have cleaned quite a few of those units over the last few years and haven’t needed to mess with the spring or replace gears. This post was the key one that helped me:

https://pinside.com/pinball/forum/topic/gtb-as-match-stepper-rebuild-step-by-step

In my experience, the key thing is to get everything clean, followed by making sure everything is aligned correctly and the little arms are not dragging on the axle at all. The switches that ride on the cam (if present) must have as little tension as necessary. I also do super lube the circuit board wipers (very little) and the switch cam. When they’re done, they should step nicely like little clocks.

There are 2 adjustments noted in the gottlieb documentation. One talks about the little blade that makes sure that it can’t step backwards. You don’t want that one pushing so hard into the gear that it adds a lot of drag. The other one rotates the cross piece to make sure that the “throw” of the armature is the right amount to allow it to click to the next spot on the gear.

Sorry for all the words. I think it’s harder to explain than to actually do it, once you’ve been successful. I was really frustrated and stuck on the first one that I did, but practice did help.

Good luck.

Dave

I had something similar on my Big Hit. What resolved my issue was cleaning the contact point I highlighted in the pic. The metal gear teeth and catch that rides on top of it were dirty and corroded.

277EEE95-86A7-425D-BCE9-6A9035EA57C8 (resized).jpeg

C30D11DA-5407-494C-B056-F8AE758B7B32 (resized).jpeg

I haven't read all of the back and forth above so sorry if I'm repeating anything there.

You want to visit the two noted switches. One on the N 10 point relay and one on the B pop bumper relay. Since there are two different paths to actuate this relay it would be odd for both of them to be out of adjustment but it is possible.

Check the power path to the relay coil. Jumper along the way.

Check the coil itself. I'd hate to think there is a break in the winding. Check its resistance.

https://pinside.com/pinball/forum/topic/make-yourself-a-bulb-tester

Your AS relay may well have needed a cleaning, but it seems unlikely that it needed new parts. Establishing whether an issue is electrical or mechanical should be near the top of things to try. In this case using a bulb tester or swapping in the other working AS relay might have established whether the circuit is working.

/Mark

I just fixed this today on mine using, what Id call the lazy mans method:
"I find it much easier to take the relay coil off (set it aside somewhere) and then soak the entire "AS" unit in Mean Green and scrub with a toothbrush. Then rinse off with hot water. Gets the whole unit clean without having to take it apart. Naturally, if there are worn parts then you'd need to disassemble it.

I clean all the gunk off the circuit boards with lighter fluid on a cotton swab or on a paper towel. Then I use 150 grit sandpaper on the copper foil then finish that with a quick swabbing of the fiberglass eraser pen.

I smear a thin coat of the Radio Shack clear lube gel on the copper foil."

This is post #16 from this thread: gtb "as" match stepper rebuild - step by step

I did exactly as he said and it worked like a charm - I got lucky - best of luck.