Bally Coin
Mechanisms

Coin Mechanisms (Coin Mechs), or Coin Rejectors, are used inside the coin door to "validate" any coins that are dropped, and to route them to the coin box if they are valid, or to the coin return door if invalid. The "valid" route will also activate the coin switch allowing the game's software to accept the coin and preform the neccessary action.

Coin Mechs operate on one type of coin only, so there are different coin mechs for different coins: Nickels, Dimes, Quarters, SBA Dollars, Tokens, etc. If you want to use coin mechs in your machine, you must make sure they are the propery type depending on which types of coins you want to use.

Also located inside the coin door is the Coin Lockout Relay. The purpose of this relay is to activate the coin acceptance function of each coin mech. If the acceptance function is activated, the coin mech will route any valid coins past the coin switch and into the coin box. If the acceptance function is not activated, all coins, valid or not, are routed into the coin return. When your machine is turned on, the coin lockout relay is activated and all the coin mechs should now be set up to accept and properly route all valid coins. When the machine is turned off, the coin lockout relay is not activated, and all the coin mechs return to their default state, which is to route ALL coins into the coin return.

If your coin mechs are not working properly, and you're sure they are the proper type for the coins you want to use, here are a few things check (click on any photo for a bigger picture):

COIN LOCKOUT RELAY

The coin lockout relay is located on the left side inside the coin door. Make sure yours
is there, and try pushing on the flap to make sure it is free to move. The lockout strip
(yellow arrow) should move freely too. When you press on the flap like in the photo, it
photo, it should easly move to the right, and should return to the left when you let up.
Then turn the machine on and make sure the relay activates. If not, you have a wiring
problem, or Q18 on the solenoid driver/regulator board, or its circuitry, is blown.

If the relay flap and lockout strip are not free to move, it could be your coin mechs are jammed up with coins or are defective in some way. Start by removing them from the machine so you can examine them:

REMOVING A COIN MECH, STEP 1

To remove a coin mech, start by finding the release lever, and raising it up.

REMOVING A COIN MECH, STEP 2

Now push the top of the coin mech to the right, while still holding up the release latch.

REMOVING A COIN MECH, STEP 3

Continue pushing until the top of the coin mech has completely cleared the mounting assembly.

REMOVING A COIN MECH, STEP 4

Now grab the coin mech and pull it up. Once the bottom mounting lugs are free of
their slots, the coin mech will free itself from the mounting assembly.

Remove all of them and examine each one for any problems, especially any jammed coins, slugs, or other foreign material that may have found it's way into the mechanism. Then it's time to check the coin lockout relay's function. With the machine off, here are a couple of things to check:

CHECKING THE COIN LOCKOUT RELAY, STEP 1

Again, activate the coin lockout relay by pushing the relay flap with your finger.
As you push the flap down and let it back up, you should see the lockout strip move
to the right, and back to the left again.

CHECKING THE COIN LOCKOUT RELAY, STEP 2

Continue to active the relay by hand, and now examine the lockout wire. It should
be moving in and out as the lockout strip moves left and right. If not, find out
where it's malfunctioning and fix it.

If you still have trouble with your coin mechs, as a last resort, simply activate the coin switches by hand. The coin switches have covers on both sides and can be hard to activate by hand until you know what to look for.

COIN SWITCHES, VIEW 1

In this picture, you can just see the end of the coin switc wire poking out of
the coin wire "slot". If you press your finger in the slot enough so you can
move the wire down enough to activate the switch.

COIN SWITCHES, VIEW 2

Here's a view of the back side of the coin switch, with the cover removed. Now you
can easily see the switch wire and how the end travels in the slot. If the back
cover is removed, you can easily manipulate the coin switch wire with your finger.

Here's two pages from the Bally Parts Catalog showing the various coin door parts along with part numbers and other information.