I picked up a gottlieb domino and have a strange problem. It starts a game normally, resets all score reels to zero. But nothing will score.

If I manually push the ones, tens, hundreds and thousands relay, they all stay locked and I get no bell or score reel movement.

That all 4 relays do the same thing implies it’s not in the relays or their score reels. Plus the score reels reset to zero just fine at game start.

Any idea where I should look?

thank you very much for the pointer. My R relay was just a hair too wide and not making contact. Its not 100% yet but at least its coming back to life!