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Default Car battery question

On Mon, 26 Mar 2007 19:09:33 GMT, Mitch Mitch@... wrote:

I went to start my Explorer the other day, and the battery was dead
from sitting so long.

I put a battery charger on it, but I'm not getting anything...zero
amps on the charger.

I've sanded all the corrosion from both contact points, down to shiny
bare metal...still nothing.

I also have a battery tender, so I put that on. It has an LED to
indicate charging...it's not lit.

Does this mean the battery is done for?


BTW, it won't kill you or bankrupt you if you rpelace a battery early.

But I think the idea was for you to get the answer for your question,
so you would know more about this for the future.

Anotehr suggestion is to measure the voltage at the battery posts.
12.6 is fully charged, and it should be higher than that if the engine
is running or there is a battery charger on it.

I forget exactly, but I think 11.6, if that is before you connect the
charger, would probably go higher, probably high enough. Regardless
of where it started, if it got to 12.4 that might be enough to run the
car. I don't remember numbers very well, but you can learn what the
various number indicate.

Most apparently sealed lead acid car batteries can still have their
caps pried off, 2 caps for 3 cells each. Best to use distilled water
to refill. (There are a lot of truly sealed smaller batteries,
including gel cells which are sealed. But there aren't too many sealed
car batteries, and it probably says it in big letters if it is. After
they came out, the battery caps on regular batteries, including iirc
lo-maintenance batteries, were redisigned to make the batteries look
like sealed ones. I think there is a narrow, barely noticeable,
1-inch slot at each end, one for each cap, if they are meant to come
off.

Fill until you see the meniscus, the place at the edge of the water
where it curls up. When the water level is low, this is out of sight
at the edge of the rectangular cell. When the water level is high
enough, the water's as high as the round tube going down from the
round hole, so you can see the curve up at the edge. That's meant to
be the proper level for the water.