On 6/26/2012 7:47 AM, Spehro Pefhany wrote:
On Tue, 26 Jun 2012 10:25:51 -0400, "Jim Wilkins"
wrote:


"Steve wrote in message
...
There's an old motor home on our property we want to get rid of. It
was
driven into place about three years ago. Apparently, no one checked
the
batteries, and they are all dried now, I would guess fried. Can one
fill
with electrolyte, charge, and hope for a Hail Mary? Or just go get
new
batteries........ three of them.

Steve

Water may evaporate but the acid doesn't. You could fill it barely
above the plates with distilled water and see if it accepts current
from a 'dumb' non-computerized charger that doesn't just give up on
it. If it does charge the liquid level will rise. Generally you'd need
an adjustable laboratory power supply to coax a little more life from
them.

If the water could somehow get out (it froze and cracked?) it's likely
that the exposed plates have oxidized and are ruined. Can't you borrow
a battery from another vehicle?

jsw


If he has good (or even decent) jumper cables he might just need to
jump start it and drive it off.


How does the voltage regulator work?
Unless it limits the peak voltage, there's likely gonna be
some stress applied to the electrical system.
Another problem is that when the RPM drops below the voltage level
sufficient
to make spark, it's all over.