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Olestra
08-26-2008, 03:49 AM
Hey everyone,

Just a quick question. I left my map light on before a week's vacation and drained the battery. I boosted the car this morning, it started up no problems and runs like new. Was able to start the car no problems three more times today.

Out of curiosity, how long does it take to charge the battery while driving around?
Will the battery charge back up to it's max capacity?
Olestra
08-26-2008, 01:38 PM
bump...? Anyone?
DaleNixon
08-26-2008, 01:44 PM
Google seems to think about 2 to 3 hours.
Kain
08-26-2008, 02:27 PM
I left my map light on before a week's vacation and drained the battery.

Not doing this seems to work best for my battery. Hope this helps.
Olestra
08-26-2008, 03:39 PM
Thanks, I of course did this on purpose.

Just thought I'd post up here to get a quick response and in case anyone else is looking for the info.
Google seems to reveal half an hour driving around is good enough, which is what I did.
oaklandopen
08-26-2008, 03:49 PM
the best thing to do would have been putting it on a trickle charge for a while, but since not everyone has the equipment or time to do it you just have to jump it and charge it normally with the alternator
MikeHTally
08-26-2008, 10:11 PM
Hmmm. I've read that it takes 20-30 minutes to replace what it took to start the engine. I'd recommend a trickle-charger. Or if you can afford it, go ahead and spring for a battery charger that can actually boost the motor.

For the time being, though, I'd say drive it for an hour (what a chore, right?) to give the alternator time to replenish the battery. Short trips and frequent restarts are what's worst for the battery.
1speed3
08-26-2008, 10:39 PM
the best thing to do would have been putting it on a trickle charge for a while, but since not everyone has the equipment or time to do it you just have to jump it and charge it normally with the alternator

Oaklandopen is 100 percent right, i am currently in school to be a mechanic and i have been tought that the best thing to do is put a trickle charge on it for an extended period of time. Calculated by using the amp hour rating or cold cranking amps. You will never fully charge the battery back agian without doing this. Your battery life will suffer from not having this done, though your alternator will charge it to above cranking voltage.
DaleNixon
08-27-2008, 08:37 AM
Take it from me: bad batteries kill alternators!

Actually I have no clue what I'm talking about.
MikeHTally
08-27-2008, 06:12 PM
Actually, you're right -- if the battery is never satisifed, it'll wear the alternator out.