All reel advance fine under normal circumstances, but when the 10k reel is NOT on zero (1-9) and the Score Control Relay (D) or Score Control Relay (C) are used to add points, the 10k reel advances each time as well.
So if the 10k reel is as 2 I can sit there and advance by 1000 points all day long and it will advance a-ok.
But if I hit a 500 point target or 2000 point targets, those are added via the Score Control Relays (to add a value >1 times) and the 10k reel advances.
If the 10k reel is at 2, and I hit a 500 point target, the hundreds will advance by 5 and so will the 10k reel.
If the 10k reel is at 8, and I hit a 500 point target, the 10k reel will advance to 9 and then 0. It will not erroneously advance when in the zero position.
This ONLY happens on player 3.
Here is the 10k reel:
Not many switches on it At zero, the left stack is closed, part of the reset sequence. On non-zero right stack is closed and left is open, so obviously I trailed that right cable.
|click to embiggen|
So check the "Add 3rd Ten Thousand" solenoid. Main option for incrementing is via the L relay and the thousands reel being in the "Carry" position, aka "9".
Other option is Z2, which is part of the reset sequence, reseting it to zero during a game restart.
The issue only occurs when the motor is chugging, via the Score Control Relays. Scoring a digit a single time is easy, but to score a hundred 5 times, or a thousand twice, require these extra relays which advance the motor.
It turns out that Z2 switch needed to be regapped. Each time the Score Control Relays advanced, the motor pulse traveled through the improperly closed switch and was advancing the reel towards zero.
Player 3, now perfectly working.
Still, player 4 issue is there:
As the thousands reel moves to "9", it is not strong enough to get it there completely in to the proper position, clicked all the forward. I think this is because in the 9 position the switch stack has flexed all the way to the right and maybe the spring is not strong enough to draw it back to it's proper position? That's all I can think of.
The result is that the next thousand fires the advance solenoid (and advances the ten thousand) but just gets the 9 to the proper position. Next thousand advance puts it to zero, but has also advance the ten thousand reel.
This machine is SOLD though. I hope I can get it all working before it goes, but it was sold with the knowledge that only players 1 and 2 were currently A-OK. Now, at least we have 3 that are aces!