How do you clean up battery acid for a PCB? Suggestions..

[Amechanic]

I just got in a Bally V2000 Video Poker machine. It plays but has a ghosting issue with the cards. After pulling the 3 board stack I noticed that the is a layer of battery forming on and around the battery's area. I see it on some IC Sockets and pins. What's the best way to clean this up? I did read the Vinager works since it an acid base. Just need to flush everything good with water and let dry for a day or two. Any other ideas??

Thanks Gary

[The Fatman]

The battery fluid is considered to be the acid and the vinegar to be the base (wrong ... it is the acid, use the baking soda) , which will neutralize the acid effects or slow down or stop any further corrosion. You need to make sure that the sockets for any chips are cleansed as well. The acid has a property that allows it to flow around the traces so a tooth brush and gentle scrub is what I would do. If the corrosion is bad you need to be a bit more aggressive and possibly replace sockets. After I do this, I create a battery holder to remove the battery from the board and mount it where if it leaks, it wont do further damage. Done this mostly in pinballs.
Dave F


Baking soda is the right thing ..... I have had many senior moments in the past few months ... this is one of them. Smile ... hope they stop soon.
Dave F

[foster]

Vinegar is acidic
Baking soda is a base

I would try water and baking soda mixed into a paste so you can control it
then a mild soap and water
I have washed PCB before with no problem, use blow dryer on warm to dry them fully.

[Badbaud]

The sockets on those old boards were cheap but had one good feature.

You can take a bent screwdriver and pop the plastic surrounding the socket pins completely off so just the pins are exposed.

Take a hot iron and some solder and heat each pin until it comes out of it's hole.

Much easier to clean the holes out and drop another socket in it's place.

While the socket and pins are out look around the traces for any excessive corrosion that may have opened up a trace.

The RAM chip usually has corrosion on the pins, it is the first one I would replace.

Second remove each of the between board straps and clean the board pins with a soft pink eraser until shiny before plugging the strap back in.

Ghost cards could also be normal burn in on the monitor.

[Amechanic]

The ghosting I'm seeing is another whole card. If you look at my picture you can see the number 10 & Q behind the left two cards. Those two cards are the far right cards 4&5. This screen doesn't have a bunch of burn it. I've seen alot worse.

Gary

[Badbaud]

That problem usually comes from the graphics card. Pull out every IC in a socket on that board and clean the pins with a soft pink eraser before re-inserting.

The graphics card is the one with 4 EPROM's in the upper right corner.

[Amechanic]

That problem usually comes from the graphics card. Pull out every IC in a socket on that board and clean the pins with a soft pink eraser before re-inserting.

The graphics card is the one with 4 EPROM's in the upper right corner.

Ok thanks.. I'll do that when I have the stack apart cleaning the battery's acid.

[Amechanic]

Are these the 4 IC's your talking about for the graphics ?

[Badbaud]

That is the graphics board, and of course you should remove those 4 EPROM's and clean the legs with a pink eraser before reinserting.

BUT there are many small chips in sockets on the board and every one of those should get the same cleaning treatment.