This is normal for most games if you have it set to 1 coin 1 play (the old US Dime setting). The 1/1 setting usually uses the "Start" relay as the source for a single credit. When set to 2 or more credits per coin, a different set of circuits is used to route multiple pulses to the credit wheel.

In almost every case, there is NO 1 credit per coin setting (providing a single up pulse to the credit wheel) as it was not necessary.

Players had to learn the hard way, if you drop in a coin, with credits remaining on the credit wheel, it will take one away.

There were also games (King Kool) that come to mind that if it was set to 3 credits per coin, it would start a game immediately and put 2 credits on the credit wheel. I am sure there were others too, but that was one I remember well from my youth.

One adjusts amount of travel to pull back and grab the next tooth. The other adjust limit of travel as the arm returns to rest and pushes the ratchet one tooth forward.

What you describe is what happens when the single pin Jones plug that would adjust the 2nd Chute value (2-5) is either not plugged in, or plugged into the wrong strip.

What we need are photos of the area right around the transformer on the floor. There should be 3 Jones plug strips. There would probably be two that are two positions and one that is 5

The decal you shows would indicate your game has the two coin function which would include an AS relay (mini stepper).

Attached photo is of my Jacks Open. Similar era, also has the alternator AS relay (designation DY relay on this one). Disregard settings and extra wiring as my game is converted to two coin one credit (50 cents per play).

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