Knockout
Bally, 1975Hello Everyone, We have a 1975 Bally Knockout, we are having trouble with the Advanced Bonus....the ball goes into the Advanced Bonus slot, but the arm is not pushing the ball back out to the playing field. Can anyone give us advice on what to check and look for to fix this?? The rest of the pinball machine is working.
Thank you
The circuit that powers just the Hole Eject Solenoid is highlighted in red below.
Both the Outhole Kicker Solenoid (which pushes the ball out to the shooter lane to start the game) and the Hole Eject Solenoid (which is the one you are talking about) use the same Motor switch 7B to fire.
If the ball is pushed into the shooter lane to start the game, then the Motor switch 7B is probably working. You only have one switch on the Hole Relay and the Hole Eject Solenoid itself (and the wiring connecting them) to check.
If your Hole Relay switch isn't closing, you might have to work backwards and figure out why that is....is the Hole Relay energizing when the ball sits in the hole? If not, why not? If so, then is something wrong with just that particular switch on the Hole Relay?
Another possibility is the hole relay hold circuit is failing before the score motor reaches cam 7, firing the hole eject solenoid.
The hold circuit consists of a hole relay normally open switch with green & black-red wires connected. The black-red wire will be found on score motor cam 10 switch B, normally closed switch. This is the hold circuit release switch and is usually the problem. Clean and adjust switch for a positive connection.
Wanna join the discussion? Please sign in to reply to this topic.
Great to see you're enjoying Pinside! Did you know Pinside is able to run without any 3rd-party banners or ads, thanks to the support from our visitors? Please consider a donation to Pinside and get anext to your username to show for it! Or better yet, subscribe to Pinside+!
This page was printed from https://pinside.com/pinball/forum/topic/1975-bally-knockout and we tried optimising it for printing. Some page elements may have been deliberately hidden.
Scan the QR code on the left to jump to the URL this document was printed from.
Charlottesville, VA