Hopper Drops coins with no error

[Olds442]

Still working on my 1998 $1 Double Diamond S+ machine that plays with large $1 Tokens

If the machine is playing with credits on board (and only if) every now and then it will drop a single coin.  When it does this it reduces the credit amount by one and it does  not generate an error.   If the machine has zero credits, it never drops a coin.

The hopper is a pinwheel style. The "optical sensor" on my hopper looks nothing like the optical sensors I have seen on line and on this forum.  It is large, spring loaded with a aluminum roller and it rocks back and rolls over the large "Eisenhower" Dollar sized tokens that this machine uses.

The coin wiper is adjusted fine and I have cleaned and lubricated the motor brake. 

pictures of the senor attached.

Some of the field manuals note that large coin machines will have a polyurethane coin wiper between the metal coin wiper and the optical sensor.  My machine lacks that wiper.

Any thoughts?

[Stayouttadabunker]

If you accidentally put in one extra coin over the MAX bet, the hopper will kick it back out.

[Olds442]

Thanks for the reply,

Yup that is not what is happening here.  Since I can hear the hopper motor turn and the credits amount decreases by 1
If you put in a 4th coin by accident it does not impact credits.  You can get a credit decrease if you put in 2 coins and play max coins, but that is not what is happening here either.

I always play three coins so my credit should always be divisible by three... (6,15,60,120 etc.) after it does this... it will divisible by 3 with 2 remainder
(5, 14, 59, 119)..,

It is like the machine/game  is programmed to drop a coin a few spins to after a win remind the player that there are credits on board. 

Weird.   

I will set up a web cam to see if I can capture the event...

[sixcardmark]

Can you adjust that roller?

[Olds442]

The Aluminum Roller on the Optic Sensor on the hopper?  It is held in by one slotted screw and it looks like it could be removed...but not really adjusted.  Unless the slotted screw is a eccentric bolt...

I'll Check.

*Edit*

Ok I checked, no the roller is not adjustable.  It is held in by a simple slotted screw that was barely finger tight.  The Engineering is quite clever,  The screw has a shoulder that acts as a bearing for the roller, it bottoms out on the senor (so no washers needed) and the rotation of the coins would turn it the right way to keep it tightened.  I gently cleaned it and put it all back together.

[Sunrise Side]

Credit limit set to low?

[Olds442]

If I slow down and document my play, the machine acts normal... and hasn't done this since I posted my question...

I'm beginning to think that Stayouttadabunker was on the right track.  If the machine is in the process of rejecting the third coin and I press max bet it will put the "bad" coin in the tray and deduct one from the credits.   

If I play "slow" or use the arm then the machine does not reproduce this odd behavior.

I'm putting this one down to user error.