Any fuses blow?

Do you have a fuse that shorted/bypassed?

Not sure, but that might be why VID tells us to install fuses on the bridge rectifiers. Do the burnt wires lead to one or both of those small boxes (bridge rectifiers) on the right side of your back box?

Yep, you can see it in the pics.

That sucks!
Where does the other side of the wiring lead to?

Looks like he'll need new:
Bridge Rectifiers with added fuses. I'd replace both.
Rewire that section and replace whatever it led to.

I don't know, does BR's alone cause this or does there have to be a short or coil lock?

This is why I install these in all my William's games.

https://pinside.com/pinball/forum/topic/bridge-board-available-for-williams-games

Replace all burnt wiring, and install the board above or new rectifiers and fuse them.
Hopefully will work after that.

Yea, that sucks, but at least it didn't burn the house down.
Looks like the bridge rectifier simply failed and shorted.
This is a design flaw in many Williams games.
I need to put the extra fuses or bridge board in a few of my games yet.

Sounds like she was killing it and Pinbot couldn't handle it.

You need to install 8A S.B. fuses for each rectifier.
It's a common problem that can be solved for under $5, and a few minutes.

co43 (resized).jpg

-Paul

Yes, this a typical case of no fuses at the rectifiers in the backbox.
One of the BIGGEST mistakes Williams made.
My Bridge Board can prevent this.
That's why I always tell people to replace the rectifiers with one of my Bridge Boards.
It add fuses and also replaces the very large capacitor for the lamp matrix.
You read all about it on my website http://www.inkochnito.nl and click on the Bridge Board image.

If you want to keep it simple, you can also just add the fuses when you replace the rectifiers.

Brug Bord 03 klein (resized).jpg

I need to do this. Could anyone tell me the specs on the BR, what gauge wire is needed to make the jumper wire, and the specs on the spade connector? I would greatly appreciate it!

Sounds like you need to visit https://www.greatplainselectronics.com/products.asp?cat=172
I think the Part Number GBPC3504L would the the rectifiers you would need.

Thank you!

The BR posted above will work fine. I used the same gauge wire that was originally there. I believe it was 14ga. Unfortunately I didn't have any blue wire to keep it the same color so I used green.

The spade terminals are just standard spade terminals for 14 - 16ga you can find at any auto parts, or hardware store.

-Paul

From what I’ve read about this type of failure it’s lucky your damage was limited and not much worse.

Question for the brain trust. Obviously he’s got to replace the bridge rectifiers, the associated wiring and add fuses. However, should the display capacitors fail, is there potential for another similar type meltdown?

I ask because I‘ve already preemptively replaced the bridge rectifiers in my Fire! machine and added the inline fuses to both my Fire! and Pinbot machines but was wondering if there was any benefit to install the board Inkochnito created.

It’s not the money, the board is well priced. If the Capacitor fails could that start a fire?

The power supply board has fuses before rectifier diodes, so no danger there.