On a two player game of this era the trough switch is past the outhole. The ball is kicked at the end of the motor rev by a switch on 4c. when the ball passes the trough switch it pulls P which pulls O by a switch on P which turns the motor. The player unit is stepped up 1 time thru 4c and a 1a pulse. If two player relay is not tripped (one player game) (PB is on relay bank) the circuit is opened thru the cam switches on cam P1 and P2 to open a circuit to pulse the unit three more times thru 1a till the cams close the circuit and motor stops its 120 degree revolution. The switches on P1 and P2 are the circuits for the Three pulses to take the unit to the next ball. The PB switch open (relay tripped) is what stops the three pulses and lets the unit stop on player 2.

If it does not stop on player 2 when two player is chosen make sure PB relay is tripping. Always reseat the jones plug between head and bottom board and look for broken connections. Make sure all switches on PB are opening and the wire connections look good (not smashed together)Check the switches on P1 and P2. It is the second state of the process that you are getting fault. The motor is turning, pulse 1 from 1a is thru motor switch 2c. now 2c circuit is closed at about 55 degrees of rev. when unit advances it closes P1c and switches P2a to a circuit thru a closed PB switch. You get another pulse thru 1a to advance unit again. Now a circuit is opened thru a closed P1 and another path thru P2 that is direct which allows for the final 2 pulses from 1a. After the forth pulse the P1 and P2 switches are back to there starting state and the motor revolution comes to a end.

The game pulses 4 times in a one player game to get to a next ball. The 1a is pulsing as the motor turns (held on by O) . The first pulse is thru the score motor. As unit advances the switches on the cams change state and give another curcuit to move to player 2 position. If the second player switch is not tripped it advances the unit again. The cam switches change again and give a path for 2 more pulses which puts the unit back at the next ball position. The pulses stop because unit could only be pulsed by the score motor which has dropped out by this time

you should get either 1 pulse or 4

If the make break on P2a was in the incorrect position you could get the extra 2 pulses. Both switchstack switches behind player unit must be correct

There is a diagram in this thread of the separate circuits posted by markg. it is the state of the switches in the switchstack. the 3rd path is responsible for 2 pulses from 1a. it gets you back to the next ball player 1 state.

make break is the switch connecting 1 side, disconnecting other when the cam moves it. the schematic is the state of the machine that has been started in a 1 player game, ball 1 served into shooter lane and unplugged from power. no points have been scored or balls played.

look at markg graph and make your switches mirror his positions. put your player unit in a ball 1 position (look at rivets on front)then adjust the switches. pulse the unit by hand 1 time and make sure yours are mirrored. continue till you get to next ball 1 position.

You are getting the one pulse that is moving the unit to player 2 position. the cams on player unit now change position and should block the next pulse because the 2nd player relay should be tripped which closed a switch on it that closed a switch to stop the next pulse to move player unit any further. The motor should only turn one revolution (1/3) turn. you should only get one pulse thru the motor switch. is your motor making an extra 1/3 rev.

did you confirm the motor is only moving 1/3 rev and not 2/3