Gold Ball Pinball Machine (Bally, 1983)

Location: Highlands Ranch, CO.
Symptoms: Wouldn’t boot, rubber rings crumbling.

This machine sat neglected prior to the current owner purchasing it.  Although the NiCad battery looked ok and looked like it had been replaced relatively recently, there was a lot of corrosion on the CPU board.  It was even affecting the RAM sockets, where I could see blue-green corrosion in the socket holes.  During the boot process, the LED would only flash a couple of times, indicating a RAM failure.

Normally I would try to fix something like this.  In this case, since there was an aftermarket CPU board available, I recommended the owner purchase the new board.  With the old board, I could fix one thing, only to learn something else was damaged by the corrosion.  It turned out I was correct, except the corrosion had spread to the sound board, which sits right below the battery.  It had damaged the sockets there as well.

I was able to get the sound board working with some cleaning.

The rubber rings and burned out bulbs were replaced, and the playfield cleaned as well.