Bally 831 schematic and repair question

[SWDan]

Hi, this is my first post here. I've had a Bally 831 for over 30 years. It's mostly worked as it should. On occasion it won't pay...and when it happens, it happens on any of the three lines. I've cleaned the switches, and they look like they're making breaking the way they should. Thing is, this doesn't happen all the time, it seems to run in streaks. Today on four winners, (different lines) it paid one time. Next week it may work every time.

Has anyone with one of these slots experienced this, and what should I look for..?

Thank you.

Dan

[wolftalk]

hey dan,

which specific model 831 is it?  The ,odel/serial plate below the handle may not be reliable, so a picture of the machine front is handy as well as the codes stamped into the slotted metal reel index discs.

if you can't post a pic here due to file sie, email it to slotpics@cdyn.com and I'll resize it.

some paperwork for various 831 models is on https://bingo.cdyn.com/slots/

in general, there's a few switches before you get to the reels and the connections to the payout counter unit that are common to all pays. 

suggest the next time it doesn't pay, open the door and jiggle or remove/replace the hopper and/or reel mech and see what happens.  If that doesn't help, got a voltmeter and/or jumper wire(s)?

[SWDan]

Thanks. I'll see about posting a pic tomorrow.   I have pulled the coin hopper before and sometimes that's helped.   I have a meter I can test continuity and voltage, and I also have jumper I've used to try troubleshooting on my Gottlieb EM pin.

[Denmark]

Hi Dan Ill bet its the zero stop thats misaligned and needs adjustment as times goes by the rubber on the zero stop gets worn and useually u can adjust that on the hopper...

[SWDan]

hey dan,

which specific model 831 is it?  The ,odel/serial plate below the handle may not be reliable, so a picture of the machine front is handy as well as the codes stamped into the slotted metal reel index discs.

if you can't post a pic here due to file sie, email it to slotpics@cdyn.com and I'll resize it.

[SWDan]

Something else it's been doing. The "winner paid.....coin accepted.....insert coin"  lights are winking off and on.  If I open the door and slam it fairly hard, the lights come back on. Then shortly after they wink out again.

[wolftalk]

everything looks consistent for the game to really be an 831-ZE

paperwork for that game is here:
 
   https://bingo.cdyn.com/slots/831-ZE/

the schematic is the w-1046-xxx file.

the common switch for the lamps you mentioned is a payout relay switch if all three lamps are on at the same time.  Jiggling or pulling out/shoving in the hopper should have an effect if it's the plugs, otherwise clean/adjust the payout relay switch with the yellow wire on the middle blade that connects to a blade with an orange/red wire (71-2) when the relay is unpowered.

if you've never cleaned the plug pins, might be worth doing.  Yank the hopper and reels and clean the black crud or crusty white stuff off the pins using a wire wheel on a dremel, wire brush, synthetic steel wool or whatever.   You can't easily clean in the sockets, so skip cleaning those but look to see if any female contacts are pushed back in the plastic body of the socket.

might as well post a pic of the replay counter unit if ya get a chance.

[SWDan]

everything looks consistent for the game to really be an 831-ZE

paperwork for that game is here:
 
   https://bingo.cdyn.com/slots/831-ZE/

the schematic is the w-1046-xxx file.

the common switch for the lamps you mentioned is a payout relay switch if all three lamps are on at the same time.  Jiggling or pulling out/shoving in the hopper should have an effect if it's the plugs, otherwise clean/adjust the payout relay switch with the yellow wire on the middle blade that connects to a blade with an orange/red wire (71-2) when the relay is unpowered.

if you've never cleaned the plug pins, might be worth doing.  Yank the hopper and reels and clean the black crud or crusty white stuff off the pins using a wire wheel on a dremel, wire brush, synthetic steel wool or whatever.   You can't easily clean in the sockets, so skip cleaning those but look to see if any female contacts are pushed back in the plastic body of the socket.

might as well post a pic of the replay counter unit if ya get a chance.

Thanks. I'll take a look at the pins later today. It does seem like a loose, or dirty connection is possible there...as wiggling the hopper sometimes make a difference ). Unless it's just a coincidence.

[wolftalk]

wiggling the hopper also jiggles the payout relay, so if a switch blade is barely making, you can see that effect also.

thumping the hopper is a reasonable diagnostic.  Assuming the hopper plug is fully seated into the socket, then whacking the hopper front won't really move the pins but can jostle the switch blades enough to improve a poor connection.

if you aren't familiar with switch blade overtravel, a bad video is here:
 
   https://bingo.cdyn.com/slots/videos/Switch_Adjust.m4v

I should mention that on double throw switches like the top one in the video, the closed half of the switch should disconnect before the contact on the long/pole blade connects to the other blade.  After the adjust in the video, it's not obvious it's doing that, so either the top blade should be adjusted back up a little or the bottom blade adjusted down.

in other words, ideally you can see a position where the long/pole blade is not connecting to either blade around it as the armature is halfway up or down.

while it often doesn't matter if all three blades are briefly connected together as the switch changes state, occasionally it can bite you.   That's not the intended design of the switch UNLESS it's specifically identified as a MBB - make-before-break.

MBB switches are rare.

[DavidLee]

Have a machine with a payout stepping unit that occasionally doesn’t reset.
Mostly happens when the machine is cold or hasn’t been run for a while.

[wolftalk]

Have a machine with a payout stepping unit that occasionally doesn’t reset.
Mostly happens when the machine is cold or hasn’t been run for a while.

payout counter reset is usually a reel mech B switch (typically wire 30 to 78-1) and the zero switch that is in front of the spiral cam (wire 78-1 to 85-1, and 85-1 goes to the reset solenoid coil).

you can temporarily jumper the zero switch closed ... then the payout counter reset coil will fire on every spin whether it needs to or not.  Or just clean/adjust the thing so it looks good.

if it's not either of those switches, all that's left is plug connections. 

problem machine an 831 or something else?