[Roadsters] OOPS

[Tom @ Datsun2000]

Daryl,

Oliver is correct about removing the negative terminal first.  The chance of
shorting the battery is almost eliminated.

There is another reason that is not so important in most of our roadsters.
Modern cars have computers and radio equipment that is always on to some
degree.  If you connect or remove either battery terminal there will be a
small spark as this equipment is turned on or off.

When you disconnect the positive terminal first the spark produces voltage
spikes that could damage sensitive electronics (and your wallet).  When you
disconnect the negative terminal first the battery acts like a big spike
filter and the voltage spikes don't reach the various electronic components
that are always on.

The rule is: always disconnect the negative terminal first, and reconnect it
last.

As to lucky.  You bet I was very lucky.  I was actually leaning over the
battery when it exploded.  Almost all of the acid went down into an oversize
rubber tray the battery sits in to protect the sheet metal where the battery
sits.  Only a few drops actually reached my skin and glasses.  The shirt has
several small holes in it now as well.  It was a loose fitting shirt and
none of the acid reached my chest.  The car was rolled out of the garage and
cleaned with engine cleaner and lots of water right after I finished washing
myself off first.

Over the years my glasses have kept many things out of my eyes.  You would
have a hard time selling me on contact lenses.  This was just one more
example to remember.

http://www.datsun2000.com/battery.htm

Tom
69 2000 - Mr. Hyde
Portland


On 4/19/2009 7:39:07 PM, Daryl Smith (drlsmith at dccnet.com) wrote:
> I think
> you're lucky it blew out the side and not more straight up! Glad you
> were not injured.
> Interesting to note that when I was growing up around and working on cars
I
> was always taught to remove the cable from the positive post of the
battery.
> It seems now that it is always made a point to remove the NEGATIVE post
> first.
> I'm
> wondering if I was taught wrong years ago, or is this something that has
> crept in with all the computers and electronics in cars?
>
> Daryl
>
> ----- Original Message -----
> From: "Tom @ Datsun2000" <tom at datsun2000.com>
>
>
> > What might happen when you don't disconnect the negative lead of the
> > battery
> > when you are working on your car?
> >
> > Nothing....... usually
> >
> > http://www.datsun2000.com/battery.htm
> >
> > But when something does happen it is dramatic, and very hard on the
ears.
> > I
> > accidentally touched the positive pole with a grounded ratchet handle
and
> > the battery exploded.  Fortunately I did not get much acid on me and it
> > was
> > easily washed off.  I suspect it was only dumb luck that my glasses
caught
> > a
> > few small dots and nothing got into my eyes.