Exploded Battery - Is this Salvageable?

[ataraxia]

I bought a Macintosh SE/30 online with known Simasimac. After opening it looks like someone has already removed the exploded battery but left the damage. The damage is pretty localised but I’m unsure if it has seriously damaged any non replaceable parts.
By my initial snooping it just seems to be everything associated with the clock that is only damaged, namely UK4 Y1 D1 D2 and R27. In addition there is damage to the legs and package of UI2-4 and UJ2-4. Possibly RP4 and RP8 as well. And as you can see the ROM socket is corroded, the ROM itself appears okay and may just need some TLC.

Either way this is my first board repair and first vintage Mac so I’m open to any guidance and suggestions. I’ve been watching Branchus creations and am going to pick up all the necessary tools, hot air station etc.

 

[dochilli]

I would remove the rust with some vinegar. After that you can see a little bit more of the damage. I had one board that has the same problems and I could rescue it.

 

[ataraxia]

I would remove the rust with some vinegar. After that you can see a little bit more of the damage. I had one board that has the same problems and I could rescue it.

Isopropyl Alcohol work as a stand in? Was gonna give it a bath. Thanks for the tip!

 

[jajan547]

Probably the cleanest leaked battery I've seen. Id say its absolutely salvageable.

 

[joshc]

Looks pretty bad to me, rotten vias and some pins in the ROM socket look properly knackered too.

 

[ataraxia]

Probably the cleanest leaked battery I've seen. Id say its absolutely salvageable.

Looks pretty bad to me, rotten vias and some pins in the ROM socket look properly knackered too.

Heres a look of it cleaned up, definitely work to do. My only real concern is whether I need a donor board or not.

 

[jajan547]

Heres a look of it cleaned up, definitely work to do. My only real concern is whether I need a donor board or not.

Yeah you have some work to do and yes there’s some corrosion that will need some bodge wires but overall if you put the time in I don’t think a donor is necessary.

 

[Johnnya101]

Or maybe if you can do precision soldering, try out a new PCB.

 

[Nixontheknight]

Isopropyl Alcohol work as a stand in? Was gonna give it a bath. Thanks for the tip!

Rubbing alcohol will not remove corrosion. You should be able to buy white vinegar at any food store or supermarket

 

[Johnnya101]

Not only that, you need to neutralize it. Vinegar will do it, or I think baking soda and water might too? Could be wrong.

 

[ataraxia]

Rubbing alcohol will not remove corrosion. You should be able to buy white vinegar at any food store or supermarket

Not only that, you need to neutralize it. Vinegar will do it, or I think baking soda and water might too? Could be wrong.

Vinegar is on the shopping list. Thanks for the guidance. Will keep the thread updated with any progress.

 

[ataraxia]

Small update, but take a look at all these corroded vias (the light shining through) any thoughts? Still too inexperienced to know whether this is fixable or not.

 

[jajan547]

Small update, but take a look at all these corroded vias (the light shining through) any thoughts? Still too inexperienced to know whether this is fixable or not.

View attachment 42131

Should be fine maybe solder through if it’s broken.

 

[Jamieson]

Some of those vias were connections from the top layer to the bottom layer, others were a connection from a top or bottom layer to an internal plane layer. I think you'll need to compare against a known good board to see what to do in each case. Just filling them in with solder will probably not work and you could risk introducing new shorts.

 

[jajan547]

Some of those vias were connections from the top layer to the bottom layer, others were a connection from a top or bottom layer to an internal plane layer. I think you'll need to compare against a known good board to see what to do in each case. Just filling them in with solder will probably not work and you could risk introducing new shorts.

This is true I’d follow this advice. If you have a spare board to test it’ll certainly help.

 

[ataraxia]

Some of those vias were connections from the top layer to the bottom layer, others were a connection from a top or bottom layer to an internal plane layer. I think you'll need to compare against a known good board to see what to do in each case. Just filling them in with solder will probably not work and you could risk introducing new shorts.

This is true I’d follow this advice. If you have a spare board to test it’ll certainly help.

Don't have another board, but do have the schematics to go off? I'm tracing all the connections from the ROM, and will repair them first and work down the list. Worst case I will order a reproduction PCB that Bolle made.

 

[jajan547]

Don't have another board, but do have the schematics to go off? I'm tracing all the connections from the ROM, and will repair them first and work down the list. Worst case I will order a reproduction PCB that Bolle made.

Like that idea, good luck!

 

[croissantking]

Have a go, but battery bombed boards are a world of pain.