The hard-stop position is the fully reset state, and it is the position for a 1-player game. The unit is reset to this position at the start of a new game by the smaller solenoid pulling in.

Each time a player is added, the unit advances forward one step via the larger solenoid. Once it has stepped forward 3 times, you'll be at a 4-player game and the unit must not advance any more. The missing gear tooth is factory; that was done to prevent the stepper from advancing more than 3 steps forward.

As polyacanthus says, the post on the gear should be on the other side of that long switch blade. The switch should be closed when the unit is in the fully reset position, and it should only open to disable the replay button when the unit is at the 4-player position. Without that switch, a player could continue to hit the replay button and subtract credits, which would be cheating the player out of their credits.

The limit switch usually gets on the wrong side of the post because someone accidently runs the unit forward more than three steps, driving the post past the long blade, which then slips behind it. You can fix this by running the unit up a few extra steps and holding the long blade out while you reset the unit and slip the post back in front of the blade where it belongs.

If the contact disc is mis-aligned with respect to the spider contacts, it can be adjusted by loosening the two mounting screws for the disc and rotating the disc into position. You will need to remove the spider to get at the mounting screws. Be sure to hold the gear in place when the spider is off, because otherwise it tends to slide out of the stepper assembly.

- TimMe