There is a lot of great data on these forums and I've been a "lurker" for a couple of years. I recently refinished a Bally Knockout (see before and after pictures below) that was pretty beat up. It required total painting on the outside and playfield as well as other internal repairs - but it's 100% working. It took a lot of time and effort and it was my first Bally (I've refinished a Williams Big Ben from scratch also).

But I have a question for fellow Knockout Owners.

When the double bonus is engaged and the ball lands in the advance bonus 3 hole, does the double bonus stay engaged throughout the ball cycle? On my machine it can easily disengage anytime that it goes through the twirly diamonds (not sure what they are called) or the center alley.

Thanks
Matt

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Thanks Rolf - yes those are before and after pics of the Bally Knockout. A lot of cleaning, painting and fixing but the back glass was good and after much effort I got all of the mechanics working. I'm retired now and slowing gaining experience.

Taking a look to the Bonus 0 Relay and checking switches this AM. Will let you know what I find.

Thanks for your assistance.

Matt

I checked the switches and they all seem to be operating ok - I've cleaned them, metered them (in both positions). The problem seems to be that when a 10 PT object is engaged (spinner or bumper) it engages the hole unit, which moves the wiper one spot and the double bonus becomes intact.

For other Knockout owners, does the same thing happen with yours? Double bonus disengaging when spinners or 2 bumpers by flippers engaged?

Yes on the ball rolling through the curved area.

The double bonus is located in cabinet along with the bonus zero relay. I can put up the playfield and watch them engage and then disengage.

I will rerun the process on Tuesday (out of town today and tomorrow) and then follow up back with you.

Appreciate all of the help.

Matt

I was home a day and now back out as my sister and brother are in town for their annual visit. Will provide and update this weekend. Thanks again Rolf for all of your help. I truly appreciate it!.

Matt

So sorry for the delay Rolf, my bother and sister were here longer than expected and I've not had time to address the pinball machine but now I'm back to "normal " life.

Some Responses :
As long in time You press - as long the Double-Bonus-Relay stays engaged ? The answer is yes, it stays engaged until I release the rollover relay. It even stays engaged when I manually hit the bumpers which toogles 10 pts and moves the center lane unit disc (which normally turns the double bonus off).

I did the wire trick (see attached photos) and with the wires connected it still jumped out of double bonus anytime the center lane unit disc turned (instigated by 10 pts from bumpers or roll over switches.

I did happen to mess up and my aligator clip was touching the yellow opposite wire on the double bonus relay (self hold switch) and that did of course hold the Double Bonus relay in and 10 pts would not kick it out. But that's what I expected.

Any other potential thoughts? I'll go through the Center Lane Unit again and check all of the wires.

Appreciate all of your help. Back working on this so I'll be much more responsive moving forward.

Thanks
Matt

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