Warning! Exploding Maxell PRAM Batteries

[maceffects]

Yes its pretty crazy not sure the issue but it seems pretty wide spread. and uniserver I'm glad there was something to save in there, I am surprised the HD is dead, maybe it has something to do with the board because it was tip top when put away years ago, even had some neat programs on there IIRC. I am surprised the PSU is good since it look liked it got hit pretty good.

[uniserver]

here is 2 completely dead ZERO volts 3.6v batteries, good news is neither are leaking!
the tadiran is made in israel, the maxell is made in japan...

[onlyonemac]

This should be stickied if not already.

Done. I might also move this to a more visible forum, seeing as this is not specifically an LC/Performa issue. The Lounge?

I don't think so. It needs to be visible to non 68kmla members. I read this a while before a member, and found it very important (although fortunately my mac hadn't suffered).

[kite210]

After reading this thread, I decided to pull out the macs I have stored in my basement to see if I had left any of the PRAM batteries in them.

I started with my G3 B&W, nothing there, then the 8500, which had a Tadiran battery in it, I decided to leave it in, as I didn't feel like taking it all the way apart just to take it out.

Once I got to my 7100, I opened it and found this:


It's still sealed, so that's a relief . I've had these machines stored for about a year now, so I'm glad I checked before my 7100 bit the dust from the maxell bomb.

I just need to check my eMac and iMac DV upstairs now.

[onlyonemac]

WHY is this not being MOVED!!! It was more or less what brought me here!

[volvo242gt]

Guess it can happen with Tadiran batteries. Tested out an SE/30 that I got today. Wouldn't boot, showed what looked like a mixture of checkerboard and the normal startup screen on the monitor. After repeated attempts to get the machine to boot, I got out the T-15. Opened it up, found some capacitor leakage that was visible from under the motherboard. Pulled the board and found this:



As per usual, the battery holder wasn't attached to the board anymore. So, I'm thinking it'd be a good idea to replace these guys, no matter what brand they are, on a 10 year schedule. Maybe sooner.

I also tore into a IIcx that came with the SE/30 and a bunch of other machines. No explosion yet from the Tadiran battery, but it was getting a little stinky and corroded looking.

-J

[LCGuy]

Remember, these are 20 - 25 year old batteries. Any battery that old can leak or even explode. They're simply not designed to last that long. Personally I always dispose of batteries when they die.

[volvo242gt]

Yep, hence the reason I'm changing them out on a 10 year cycle now. Need to change out the one in the G4, since it's likely the original Tadiran from 2001.

-J

[mcdermd]

I just leave them out. 95% of Macs will boot without them and the once in a while that they are turned on after being unplugged, I can set the time or let the time get set via NTP.

[uniserver]

yeah its a shame to have a battery destroy a main board like that.

[directive0]

On the topic of Network Time Synchronizer:

Does anyone else have problems with it crippling your computer? I have 2 7100's running OS 8.5.1 and they both just lock up until command-opt-escape lets me force quit (and when I do its ALWAYS Network Time Synchronizer thats doing it).

I've left it for hours and come back and it's still locked. Is there something I can do to get it working properly?

[techknight]

i ran it on my SE/30 back in the day and never had issues.

[insaneboy]

hummm maybe I should check the SE/30 at work... although it's on a really high shelf and I don't do heights.

[volvo242gt]

^ If necessary, have a coworker grab it. But, yep, I'd check it.

-J

[Nathan]

You could just tape up the compartment with masking type or something else, couldn't you? Might help reduce the chance of the board getting destroyed.

[LCGuy]

I doubt it. But whats the point given that the battery is most likely already dead, and you've got the machine open, and can remove the battery, therefore removing the risk completely?

[Brett B.]

I haven't specifically seen a Maxell battery blow up, but I've dealt with several other brands. Don't remember which. Really, it doesn't matter, they can all leak.

IMO there is zero reason to even have a PRAM battery in any old Mac that you are not using on a daily basis that doesn't require it to boot. It's just too risky and there's no reason to damage your equipment with a battery that explodes.

[genie_mac]

Another one bites the dust...or should I say has bitten the dust:
Picked up an LC with monitor for a tenner today and was told it wasn't working. When I got home and spotted all the rust on the backpanel I got suspicious...more rust than usual....this couldn't be, could it???



Looks like a Maxell alright. Mind you I also have an unexploded Maxell from 1992 but the plot thickens....

I didn't know caps could turn into mushrooms either....



Ah well at least the harddrive, floppy and PSU are still OK...now can I use that floppy in my SE?

[uniserver]

wow that is terrible and cool all at the same time

[markyb86]

You can use it in the SE if it is the FDHD or Superdisk model, or if you have roms from either IIRC

[uniserver]

or you could scrape it off really good, toss it in the sink and scrubb it. try a re-cap, maybe it will fire right up ?

[LCGuy]

I didn't know caps could turn into mushrooms either....



Ah well at least the harddrive, floppy and PSU are still OK...now can I use that floppy in my SE?

What is that....that.....stuff? That couldn't *all* have come from the caps, could it?

[onlyonemac]

It's probably the result of a reaction between the capacitors and the battery acid.

[genie_mac]

Yeah looks pretty cool alright, not if you're a poor LC though.

Have decided to try and get it going again; have scrubbed it down pretty well and it doesn't look too bad. Have to replace the caps alright and not sure if the pads are gone...also have to resolder some pins of the 68020 which have come loose...very strange. The only major problem is one of the socketed chips (what are they?) where there is major corrosion. If I take it out, I'll probably loose half the legs

Well I'm away for a few weeks so this will have to wait...might start a new thread once I have something to report.

Laters.

PS: Thanks markyb86, will try that; my SE works with a FDHD alright so that's great.