Bally Lost World (Bally, 1978) fuse problem.

[Pinball2002]

I have a 1979 Lost World machine that just started blowing a fuse. It used to work perfect and then one day I turned it on and the fuse blew. I've replaced the fuse many times but it keeps blowing out. I even tried a fuse that had a higher rating, but that blew out also.

I am pretty mechanically inclined, but I'm a little nervous about jumping right in with electrical issues -- given how old the circuit boards are.

Does anyone have an idea where I should start? What may be the cause?

Ironically, a coworker and I were talking and I found out that he is into pinball also. He has a different Bally machine from the same time period, and he has the same problem.

 

[Itchigo]

What does the fuse go to? What is the value of the fuse? Does the fuse blow right away or does it take a while? Have you replaced any solenoids recently or have you had any solenoid problems? Likely but not always it probably is a shorted wire. Usually it is not a board, but not impossible.

 

[faralos]

NEVER NEVER replace a pinball fuse with a higher rated one! not only may it start a fire but it could wipe out your entire motherboard too! but I'd check for a stuck switch somewhere, maybe two wire (they look like flat pieces of metal) contacts are touching, after that look at the fuse box area. Make sure that the fuse contacts are clean and shiny! then check (go into the bookkeeping mode check all solenoids, switches, lights etc. If after all that it still pops fuses, you may have to pull the boards and have a look-see on it. check for broken solder joints (they should look like little mounds if shiny solder, and cracks means you have to (using an adjustable temp solder station) put a new drop of solder at that connection. Buy a 'solder sucker' too to remove the old solder. but go thru everything else first, pulling boards should be the last choice...

 

[faralos]

damn you itchigo ya' beat me to it, :D but yeah check for bad wiring (personally i still feel it is a stuck switch, if it were a wire it shouldn't even work at all not pop a fuse, unless they are crossed)