Cap kit for 7100/66

zeedub

New Tinkerer
Mar 22, 2025
2
0
1
Hi all,

I'm just getting started in the world of vintage Macs and have recently picked up a 7100/66.

I'm really impressed by how organized and prepared the vintage community is in helping enthusiasts with much of the routine and preventative maintenance associated with preserving or restoring vintage computers. I'm finally encouraged to take the plunge.

First, is the 7100 generally in need of re-capping? From what I've seen on-line (YT), all Macs will need re-capping sooner or later. But checking just to be safe.

And if so, are there existing kits for this model of logic board that have all the caps necessary for a full recap? If so, I'd appreciate a referral to such a source or supplier. My preference would be for tantalum caps unless the price is absurd.

Also, would such kits also include caps for the power supply, or are there similar but separate kits for those? Many videos (TDNC, AR) I've seen show PSU caps seemingly much less likely to need re-capping.

If it'd help if I shared more specifics of my system or situation, just ask, and I'll see what I can find.

Anyway, thanks in advance!
 

eric

Administrator
Staff member
Sep 2, 2021
1,052
1,738
113
MN
bluescsi.com
Welcome!

While no component will work forever once you start getting into the early power mac's like the 6100/7100/8100 I haven't seen them leaking much yet. That said you should visually inspect them and look if there is a wet looking substance around your caps. I don't have a 7100 motherboard in front of me but I'd guess the majority of them are 47uf 16v which can be purchased from mouser/digikey in the US fairly cheap.

If you could share a few photos we might be able to help identify and give a recommendation.

Also consider your skill level - if this is your first recap and you've not soldered before you can cause more issues with preventative maintenance. But if you want to learn too you shouldn't stop yourself from trying either, just learn on a few other scrap things first.

RE: PSU's - that starts to get even more tricky the later you go with different manufacturers of PSU's in the same models of machines. Usually you'll have to create the cap list yourself, measuring spacing, etc. Again if it's working well (voltages stable) and no visible leaking, it may be better to leave it.
 

phunguss

Active Tinkerer
Dec 24, 2023
373
327
63
Stillwater, MN
Since my 7100/66 was accessible, I pulled the cover and power/drives and took some photos for you.

7100-66a.jpg


7100-66b.jpg


7100-66-nubus.jpg


7100-66-pwr.jpg


7100-66-psu.jpg
 

zeedub

New Tinkerer
Mar 22, 2025
2
0
1
Ah, thank you both.

Here's some photos of mine.

Mine looks quite similar to yours. So, not bad, it seems.

I see that Colin (TDNC) often performs an alcohol bath. Would that be good here? I used some canned air to blow off dust, but there's still room for improvement.

Any suggestions would be appreciated.

Thank you!

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