If the game works correctly when set for 3 ball play, this motor switch is probably gapped too close.

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yes

Does the Coin relay hold on for the entire time the balls are counting up?

During game reset
The Ball Count step up coil is pulsed through the Coin relay.
The Coin relay is held on through the score motor switches in my earlier post
or through one of these circuits.

If that doesn't help you and you'd like to try a phone call, send me your phone # in a private message

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All that sounds right.

My copy of the manual doesn't show the 5, 10 and 25 cent relays. Yours might if you have a paper copy.
If you have a 5 cent relay it would be on the Mechanism Panel (bottom board with the motor)
Do you have the 5cent adjustment?

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