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I got some compact macs and they both dont work :(

First up is a IIc rom255 pre serial fix, very early. Board looks good but going to recap preventatively before powering up. (not a compact i know)

Second is a mac plus with 4MB of RAM, chime but no screen, going to look into the common reflow on the connectors and maybe recap the AB

Lastly is the mac classic II with a hard drive and 2MB of SIMM for 4MB total.
Sadly it has the PROM bomb. It looks like it was stored on its back for most of the leak as the metal chassis is MASSIVELY corroded instead of pooling on the LB. (I have removed the PROM batt, one pin was corroded off the other i desoldered, took 400C and flux and was still tough)
Is this worth cleaning up and then putting power to without a full desolder deep clean? Or should i sell it for parts?
I dont have time to put days into a deep clean but id rather not destroy a parts board powering it up half cleaned.
Thoughts?
 

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That board is on the verge of what I would bother spending my time on, but you'd be surprised how resilient some of these things can be. Some time with the appropriate chemicals and a toothbrush could probably clean that up, and you might have success.

If it were me, I'd at least take a whack at it. But anything past about that level of damage I'd walk away from. You should see one of the Classics we've got at work on display - the logic board inside it is absolute rust from the PRAM battery.

Edit: On second thought after reviewing the pics, those vias look gone... I'd give this a preliminary clean and test and see what you get. If it works, fix it up, if it doesn't, move on.
 
That board is on the verge of what I would bother spending my time on, but you'd be surprised how resilient some of these things can be. Some time with the appropriate chemicals and a toothbrush could probably clean that up, and you might have success.

If it were me, I'd at least take a whack at it. But anything past about that level of damage I'd walk away from. You should see one of the Classics we've got at work on display - the logic board inside it is absolute rust from the PRAM battery.

Edit: On second thought after reviewing the pics, those vias look gone... I'd give this a preliminary clean and test and see what you get. If it works, fix it up, if it doesn't, move on.
Down by the FDC plug it looks like the electrolyte has gone down a via and delaminated internal layers.
I had read some apple specific ICs could only come from harvested boards. Would a power on in a badly corroded state kill those rare chips (if they exist on a Classic II the RTC i think one was). Or should i find someone needing a donor board?
I have no interest in a classic II but dont want to just throw a board out / most likely fry it more with power.
 
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