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Battery/Charging question

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R6MGS

R6MGS

Yoda
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When I got the 6 the battery was completely dead, so I took a battery from an MGA and dropped that in to fire it up. Now I noticed the charging/amp meter guage reads about half past the middle, is this ok? Is it because the MGA battery is smaller than the 6's?
Also I have had the 6's original battey on charge for about 24 hours and it seems to be coming back....very slowly...but it's getting very hot is this a sign of anything?I've been unplugging it and letting it cool.
 
The question is: do you have two 6v batteries in the MGA or one 12v? Just having a smaller battery won't make a difference, because the size of the battery usually translates loosly to a difference in cold cranking amps (larger batteries can't crank stronger for longer, while a battery to fit a Miata or Lotus Elan is basically dead within 15 seconds of cranking.) BUT if you try to put a 6v battery in a 12v system, bad things can happen!

If the system is charging significantly even at idle, you might have an overcharging problem.
 
It's a 12v battery...Forgot to mention that. I am not sure what it's doing at idle...I'll make sure I look next time I start it. If it is over charging what bad things am I in for?
 
Very hot is probably not good. Especially if is a maintenance free battery without removable caps. I would pull the battery off the charge, test to see if it is functioning. I had one go hot a few years ago, and it was shot. Some folks have had success in heating them up and rejuvenating them.
As for the gauge. Your car should have a volt meter. It should be sitting around 13 volts when running, which is a little right of center. If the battery is a little low, it will probably show higher than 13 volts.
 
Yeah, I am talking about the volt meter.....for some reason I couldn't think of the proper name....Even though it says volts right on it! It's running a little pasr 13 volts.
It's not a maintence free battery, but a newer looking CAA battery.
 
If it gets hot without being up to full charge, see ya later.

You should be at 13.5 to 14.2 volts at idle and the battery should be able to withstand a full load test cycle. If not, make sure AAA is paid up.

Seriously, I think it's time for a new battery. But this begs another question, via the chicken and egg theory. Is the battery shot because of the alternator or is the alternator good and the battery is just shot? The only real way to know is to get a known, good, fully charged battery and then take all readings with a reliable voltmeter.
 
Well the battery in it now is a good fully charged battery(just a little small for the compartment) so I'll check the reading next weekend and see what comes it. I think it was idling at around 14 volts.
 
I would think that output from the alternator should do rather nicely, but check it with a reliable meter to be sure. Old gauges can be iffy.
 
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