Alternator not charging batteries??

Posted By: 67GTMIKE

Alternator not charging batteries?? - 09/23/10 01:59 PM

Big block, elect water pump and fans, duel batteries in trunk, running in series.

I had a single wire 90 amp alternator installed and it is not doing crap. Tester shows it putting out amps but, it does not appear to be charging batts. My Volts gauge showed about 14 volts, after driving 15 minutes, it was down to 8 volts.

Any suggestions, not used to having duel batteries, am I missing something?

Posted By: Rick_Ehrenberg

Re: Alternator not charging batteries?? - 09/23/10 02:35 PM

These dueling dual batteries that are in series...they are each 6V batteries?

Rick

Posted By: 71_deputy

Re: Alternator not charging batteries?? - 09/23/10 09:49 PM

also check at each battery the voltage to them- maybe the 14 volts is not getting to them!

Posted By: terzmo

Re: Alternator not charging batteries?? - 09/23/10 10:31 PM

two 12 volt batteries in series is like one 24 volt...why are you running this configuration ??

People upgrade the alternator to support electric fans and such....you have a 12 volt output supporting a 24 volt system...again....why ??

Posted By: Sinitro

Re: Alternator not charging batteries?? - 09/24/10 02:09 AM

Quote:

two 12 volt batteries in series is like one 24 volt...why are you running this configuration ??

People upgrade the alternator to support electric fans and such....you have a 12 volt output supporting a 24 volt system...again....why ??

As mentioned (2) 12V batteries in series equals 24V, instead the batteries should be in parallel for double current but @ 12V. The alternator assuming it is a standard Mopar one can only charge 12V batteries.

Just my $0.02...

Posted By: terzmo

Re: Alternator not charging batteries?? - 09/24/10 02:18 AM

two 12 volt batteries in paraleel will only deliver 6 volts

Posted By: 71 Charger R/T

Re: Alternator not charging batteries?? - 09/24/10 02:30 AM

Quote:

two 12 volt batteries in paraleel will only deliver 6 volts

What?!

Posted By: Supercuda

Re: Alternator not charging batteries?? - 09/24/10 02:58 AM

Quote:

two 12 volt batteries in paraleel will only deliver 6 volts

Math, spelling, whatever

Posted By: terzmo

Re: Alternator not charging batteries?? - 09/24/10 03:05 AM

paralell...happy now

Posted By: OzHemi

Re: Alternator not charging batteries?? - 09/24/10 03:07 AM

Quote:

two 12 volt batteries in paraleel will only deliver 6 volts

Ummm, no....2 batteries in parallel will still have 12 volts.

Posted By: DTM_Motorsports

Re: Alternator not charging batteries?? - 09/24/10 03:11 AM

well if they are fighting each other (dueling)
then maybe they are using all their energy..

Dual, not Duel ...

Posted By: RapidRobert

Re: Alternator not charging batteries?? - 09/24/10 03:13 AM

67GTMIKE please chime in

Posted By: Supercuda

Re: Alternator not charging batteries?? - 09/24/10 04:07 AM

Quote:

paralell...happy now

Fail

It's parallel

and two batteries in parallel are still the same voltage but increased current capacity.

Posted By: 451Mopar

Re: Alternator not charging batteries?? - 09/24/10 04:34 AM

I hope you guys are just joking around or this is just sad

Two 12-Volt Batteries in series is 24-Volts, double the voltage, but same current rating as one one battery.
Two 12-Volt Batteries in parallel is still 12-Volts, but twice the current rating.

If your running an alternator you usually only need one battery to get the car started then the alternator takes over to power the car and recharge the battery. The dual batteries in parallel gives extra current capacity to maintain the 12-volts longer when there is no alternator to supply power.

Dual batteries are used in Diesel trucks because the starter motor operates on 24-volts, where the batteries are temporarily connected in series, but charged individually through a battery isolator.
HD non-diesel trucks that have dual batteries will charge the batteries through an isolator, but the truck basically is operation on just one battery with the second one in reserve for things like wenching.

Posted By: Andrewh

Re: Alternator not charging batteries?? - 09/24/10 02:36 PM

Quote:

two 12 volt batteries in paraleel will only deliver 6 volts

voltage does not work that way.
Resistance in a circuit works that way.

Posted By: terzmo

Re: Alternator not charging batteries?? - 09/24/10 05:24 PM

yepper....My mistake on that part...but he's still running a 24 volt source in a 12 volt system

Posted By: Andrewh

Re: Alternator not charging batteries?? - 09/24/10 06:40 PM

well that depends on how it is actually wired.

Posted By: 67GTMIKE

Re: Alternator not charging batteries?? - 09/27/10 02:51 PM

Thanks for all the replies..

The 2 batts are in series and shows just under 14v on my volt gauge when charged, car is setup with large fans, elect water pump, stereo system, ect.. so I assume that is why the extra battery was installed.

I installed a alternator, so I would not have to charge the batts manualy anymore. For whatever reason the vbelt was defective.
I picked up another and everything is working perfectly now. I thought I had done something wrong but it was just the belt.

Thanks again-