Should I take out the pram battery?

[hexstar]

I have a collection of vintage compact macs, they are:

* Mac Plus

* Mac SE FDHD

* Mac SE/30

* Mac 512k

* Powermystic Color Classic

* Takky Color Classic

and I was wondering what would be the best things to do to help preserve their working state? Should I take out the pram batteries? They would still boot, only difference would be the time would always be wrong right? I've heard that I shouldn't worry about the capacitors until they leak since that can be solved simply by replacing the capacitor(s) in question and cleaning up whatever mess may have leaked out, is this correct? Anything I'm missing? Thanks!

 

[The Macster]

If they are used infrequently then it's best to remove the battery I think - this will also keep the battery from running down. If the battery is dead then just throw it away and run the Mac without it - no battery is better than a dead one as dead ones just leak and cause damage. I think it's better for the capacitors if the machine is started up every few months, though there's not much you can do to stop them leaking, this sadly happens in the older machines and has lead to a lot of Mac deaths ( :'( ) - the machine will work with leaky capacitors until there is so much gunge that it blocks circuits on the board, you can then clean it off to get it working again but I tried wiping it off in my LC II and it still doesn't work, I think you would have to risk the "immerse in water" thing to get it off and returned to a working state.

 

[slomacuser]

another problem is that the SE macs have battery built in ...

 

[aftermac]

I would pull the batteries out of any computer that you are not regularly using. I have lost two PM 6100's because the batteries exploded destroying the motherboards, power supply, and cases.

another problem is that the SE macs have battery built in ...

If the battery is registering under 3.3v, I wouldn't hesitate to clip it. If it is still good then I would check the battery and start the computer up regularly. A couple weeks ago I clipped the battery in one of my SE's and soldered in a new battery holder.

 

[hexstar]

Thanks for the replies guys, I will be purchasing a long torx screwdriver and from there remove the batteries from my collection as while they do get usage they definitely do not get daily usage as much as I'd like them to

 

[equill]

New half-AA lithium batteries cost USD4 each from at least one eBay seller. If PRAM batteries are 'spared' by permanent attachment of the Mac to the live mains (but not switched on) they will last from 5-7 years. That is close to their 'shelf' lifetimes, and it makes for an insignificantly small battery running-cost. There is no practical advantage to removing the batteries between uses of the Macs, considering the time and effort involved in doing so in the compact AIOs.

Capacitor degeneration is a real possibility in the Macintosh to Plus group, which use a scarce, costly, 4.5-V cylindrical alkaline battery. The battery is easily accessible without opening the case, but removing the battery does nothing to prevent capacitor degeneration, and nothing to preserve the battery. On the other hand, if the original capacitors have not bulged or leaked by now, they are not about to do so imminently. If they do leak, the fault is in their manufacture, and not in the trickle current that spares the battery.

So all-in-all, there is little advantage in removing the batteries unless you plan storage/idle times of years or more. I have 28 Macs in my study, and that includes 13 desktop 68000 and 68030 machines, all permanently connected to the mains. Any one of them can thus be started up at a moment's notice. None of them has developed leaky capacitors in the last seven years, and those that arrived so were cleaned-up when they arrived. YMMV, naturally, while Murphy lives, but the state of your Macs' batteries and boards is not one that needs to do dreadful things to your intimate apparel.

de

 

[Charlieman]

another problem is that the SE macs have battery built in ...

...and they last an incredible length of time. However, it is probably time to snip them and replace with a battery cage or a clip on.

Mac Plus and earlier: remove the battery when not in use, unless it is a recent replacement. The damage caused by a battery leak is non trivial.