Troubleshooting / Fixing The Coin Mech

I had the time today to get round to looking at the coin mech on the cab.  Prior to today I’d been running all my games in freeplay mode which is convienent but not really authentic.  When I got the cab there were two issues with the coin mechanism.

1. It was set to HK dollars (which I had none of given I dont live in HK).
2. Once I did get hold of HK$ they just got stuck when I inserted them.

Luckily this was an easy fix and only took a few minutes of investigation after removing the mech from the coin door (two screws to remove for the mech and two for the coin microswitch).

Once out you’re left with a good view of the mech:
1. Reject mechanism + Magnet
2. Coin Width adjustment screw
3. Coin Weight leaver (I think).
4. Exit Adjustment Screw (I think).Coin Mech Det

Running some coins through the  mech they were getting jammed straight away before position 2. This screw was lose and the coin could not physically get in to the mech from the slot.  Simply moved the screw to the left and tightened (see pic below #1).

Next up the coin would fall in to the weight leaver (position 3) but get stuck.  I initially thought I was missing a spring as manually moving the leaver passed the coin in the the rest of the mech and down the correct path but it woouldnt return to the initial position causing subsequent coins to be rejected.  Turns out it was simpler than that.  It’s actually specifically weighted for the HK$ coins and should simply fall in to its “closed” position when no coin is inserted and “open” when a coin of the right weight is inserted no spring required, just gravity.  This wasnt happening simply due to rust!  A quick squirt of WD40 and a clean at position 2 (pic below) ment that the coins would now travel through the mech, the weight would tilt and return correctly with each coin.

Coin Mech

Reatttaching the mech to the door and adding the microswitch back at the end of the path gave me a working mech.  Bad / foreign coins get stuck as you’d expect but a quick press of the reject button and we’re away again.  The door still needs a clean but it’s nice to have another small annoyance fixed.

Here’s a quick video overview of what I did to fix the mech:



About Alec Dunn (LegoYoda)

Alec is an IT Architect focused around large private / hybrid cloud design and automation. He's also a big fan of the 'arcade' culture and games of yesteryear and loves taking things apart to see how they all work.
This entry was posted in Arcade Hardware, Hardware, Teardowns and tagged , , , , , , , , . Bookmark the permalink.

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