I've had the Bank-A Ball for some years it has worked well until now.

The symptoms were that it would not start a game, the motor would spin, reset all the relays and stop, but the playfield lights would not come on.

One day I turned it on - I was playing some other games and just wanted the backglass lights on. about 1/2 an hour later I could smell burning, smoke was coming out of the backbox, I turned off the power then opened up the backbox. I think 1 of the reset coils for the animated balls in the backglass had locked on, I am guessing that was where the smoke came from as it now has a very toasted wrapper.

I left the game for a few weeks and now I am looking at repairing it. I don't have a lot of experience with EMs but i have a schematic and can read it.

The symptoms now are that 1 of the 10amp fuses blows soon after power is applied. I have inserted a 5amp circuit breaker to save on fuses but this pops soon after power up, the motor starts and spins but doesn't seem to want to stop and then the circuit breaker pops.

I tried disconnecting all the plugs between the head and the body and then powered on, same thing happens, the circuit breaker pops. Does this mean that the problem / short is in the body? maybe somewhere on the main relay board?

I'd appreciate any instructions on what to do next, how to proceed to find the cause of the fuse blowing.

Fair enough on the circuit breaker size. I now have a 10 amp circuit breaker and I get the same result.

Is there a procedure to follow to find what is causing the short?

I'm pretty sure the problem is with the score motor. I desoldered 1 wire from the score motor and then powered up. The circuitbreaker didn't trip. I then moved the score motor manually stopping at each position for 10 seconds, the circuit breaker was fine.

I then touched the wire back to the score motor and it spun for a few seconds, the wire in my fingers got hot and the circuit beaker tripped.

So now what do I do about the score motor. I think that Pinball Resource repair them but I am in New Zealand so this could be expensive just in freight. Can I use any motor from a similar aged game? I know someone who has some parted out EMs.

Hi Mike, I agree it is not 100% a motor fault. The motor does spin but fuse (a 10 amp circuit breaker on the 25 volt supply) blows. Just ran it again and there is a burning smell, I think it is coming from the motor.

Could it be partially shorted? I'll try the resistance measurement across the windings later today and see if that explains anything.

I realise that once I sort out the fuse blowing issue I will have to figure out why the score motor does not stop spinning, and why it starts spinning as soon as I power the game up.

MikeO, I did that with the circuit breaker, are you suggesting I use a fuse for this test?
In any case there were no circuit breaker trips with the the motor out of circuit. A few seconds after connecting the motor the circuit breaker trips.

I measure the current that the score motor draws when running 19 amps using a clip on ammeter. I need a replacement motor.