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RE: Battery Question

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Subject: RE: Battery Question
From: "James Fischer" <>
Date: Wed, 13 Aug 2003 13:14:36 -0400
> QUESTION: Why 10.5 volts? What's magical about that number?
> Will the MG not run below 10.5 volts?

To have a standard, one has to have a "standard test".
Since most car electronics designed for 12 volts will
not function below 10.5 volts, how long a car battery can
"live" is defined as "how long before it drops to 10.5 volts".

> I have added equipment that exceed the generator's capability
> at night.

More amps than horsepower, eh?  :)
I'd guess that your lighting system switch needs a relay
to keep it from overheating and melting.

I had the same problem with a 72 MG Midget. The lighting system
was nice and bright, but the real answer was a bigger alternator.
I have no idea what one might fit to a 1951 TD, but our 1952 TD
looks like it could take quite a few different generators if one
were willing to mess around making a few brackets.

Have you considered the new LED lighting systems?
Super-bright and expensive, but much lower current
drain.  Less energy is wasted as heat, and the result
is more light with less current drain.

> (plus Radio/CD, etc.)

A CD in a TD???  Sacrilege.  :)

> If my calculations are right, I can drive under those
> conditions for 7.5 hours before the voltage would get
> to the 10.5 volt level, more than enough to get across
> Florida from weekend car shows.

...and if you are wrong, you end up stranded on the Florida
Turnpike, Alligator Alley, or the Tamiami Trail at 2am.
If this happens, remember that your starter crank (you DO
have a starter crank, don't you?) not only will start the
car on a dead battery, but also makes a handy club for
keeping the gators at bay until you get the car started. :)

        james fischer

        MGs in Summer, Volvos in Winter,
        so wrenches are constant companions

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