Bally Eight Ball.. kickout coil issue?

cueball

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I got my Eight Ball almost 100%. I want to figure out what is wrong with the rest of it before I order parts.. right now, the kickout coil at the bottom of the playfield doesnt fire.. Instead, when that switch is depressed, the outlane kicker fires. The outlane kicker also fires when it's own switch is depressed.

is it firing when the outhole is triggered, because the outhole coil is bad? I thought if a coil was bad, it would short/burnout?

I only have 3 coils that may need to be replaced: knocker (low priority, but will replace if i have to place an order), a chime coil and possibly the outhole coil. I want to get it running before i start buying 'spare' parts that i dont need (yet), so I want to make sure the issue is the coil and not something else.

thanks
 
is it firing when the outhole is triggered, because the outhole coil is bad?

No. Definitely not.

I only have 3 coils that may need to be replaced: knocker (low priority, but will replace if i have to place an order), a chime coil and possibly the outhole coil. I want to get it running before i start buying 'spare' parts that i dont need (yet), so I want to make sure the issue is the coil and not something else.

thanks

What makes you think these coils need to be replaced? Are they burnt? Are they shorted or open?

Sounds like something funky is going on with the switch matrix. Could be a missing diode. I would have to look at the layout of the matrix for that game to say for sure if that would cause your problem but it seems like a likely cause to me.

I would go into the switch test and see if the MPU is seeing the wrong switch closure when you press the outhole switch. If so I would suspect a missing or shorted diode in the matrix or some funky wiring that someone did.

Could be something else but that's where I would start...

I want to make sure the issue is the coil and not something else.

The issue with the wrong coil being energized is definitely not related to a bad coil. There's really no way that would be possible.

Like I said... I would start by seeing if the MPU is reading the wrong switch closure. It's possible it could be reading the matrix correctly and have a stuck data line going to the 1/16 decoder on the driver board or a bunch of other stuff but I would start there.
 
The knocker coil is shorted/burnt, so i know that needs to be replaced. I will order that later when I know everything that I need.

the chime coil and the outhole coil look good. I am probably going to switch them with other known working coils to eliminate them as an issue.

where is the "switch matrix".. is this on the SDU board?

as far as hacks/repairs, i was told that one day the game stopped kicking out the ball.. so maybe it is likely that it is related to the switch matrix that you are referencing..

i will likely have more questions tonight when i start to dig into it.
thanks!
 
I am probably going to switch them with other known working coils to eliminate them as an issue.

Just check them with a meter. Much faster. You can also test them by manually grounding the metal tab on the associated driver transistor but I would check them with a meter first if you suspect a problem.

You should read though this:

http://www.pinrepair.com/bally/
 
metered the coils.. they are within spec.. ran the coil test again and wrote down the order.. it is a little different than initially mentioned.

Coil test:
1. outlane
2. <nothing>
3. outlane
4. chime1 (not sure of name, but it is the largest of the 3 chimes that are together)
5. chime3
6. chime3
7. <nothing>
8. Bumper (upper right)
9. Bumper (upper right)
10. left slingshot
11. left slingshot
12. right slingshot
13. coin lockout
14. SDU flipper relay.

one thing that I did notice is that there is no transistor at Q2.. the holes arent even filled with solder (but it doesnt look like something fell off either)..

thoughts?
 
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Well, I answered some of my own questions, but the game still isnt 100%.. I checked all of the solenoids via the SDU "ground the transistor" method.. After going through this then back to the coil test, the coils are firing when they are supposed to..
BUT, I still am not getting the Extra Chime.. When grounding the transistor, i dont get any activity when grounding Q3 (knocker that is disconnected?) , Q7, Q12 or Q16-Q19 (nothing left for these to fire)... is Q7 the Extra Chime?
 
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