What is a good 12V battery voltage reading?

[Kern Dog]

Oh yeah...Many topics get off track!

 

[themechanic]

Optima makes 2 battery chargers that have a maintenance cycle.

I have a good old Interstate battery in my Coronet. Uncle Bill put an Optima in the Cuda. I have a Battery Tender Plus maintaining both.

https://www.optimabatteries.com/en-us/battery-charger

http://products.batterytender.com/Chargers/Battery-TenderR-Plus.html

 

[Kern Dog]

My Uncle Bill was a drunk. In fact, ALL my Uncles were drinkers. I called them my drunkles.
Bill was a transmission rebuilder. He was married 5 times !

 

[RJRENTON]

You know Bob, I had a Maintenance Supervisor that questioned everything I did as the plant Engineer back in the '80's while working in the most modern glass bottle plant in North America and he did all he could to discredit my knowledge because I was 20 years his junior .... and when it came down to it he had no idea what his job really was. From this and other previous posts of yours at me it seems you're on the same track for some reason and as I told him, do your own research and maybe you'll keep YOUR job. You type a lot of redirect and never seem to offer any real advise here.

Thanks for the comment. Who was the plant engineer....you? What was your dicipline? If I were your subordinate, I would ask you for your reason for your decision...not to criticize but to learn. Age has nothing to do with the decision. As far as questioning your comment, what is the basis for your comment...it sounds like a "they said rule" or becsuse "I said so" rule. Proclamations without some substantiation as to their validity is just an opinion....and I'm sure you know the saying about opinions.
As far as my experiences and educational level goes, I was totally responsible for a 75 man plant maintenance department and a 5 million dollar annual maintenance budget at a mid West chemicial plant where chlorine and sodium hydroxide was made by electrolysis of salt water, ethylene chloride, methylene dichloride and their derritives were continuously manufactured. I am a registered Professional Electrical Engineer with a B.S Electricial Engineering and hold a M.S Business Administration in Macro Economics. Over the years, I've learned to ask why and not just accept a premise. Is this right or wrong? It depends on one's point of view.
BOB RENTON

 

[ynst]

12.7 on a fully-charged 12 volt battery.

Optima batteries are NOT deep cycle batteries. i.e. they're not designed to be fully depleted. If you pancake an Optima battery, replace it

Optima batteries require a higher charging rate than a normal lead acid batteries. FWIW, you can't maintain an Optima battery with a generator. You need an alternator. The generator will overheat at highway speeds trying to keep the Optima battery charged.

As for stand-alone chargers, invest in one with multiple battery-type settings and select the proper setting before turning on the charger.

 

[Stevecurley]

Given the number of vehicles produced since 2000 by GM that will not start with less than 12.8V how can it be that a new battery with less voltage would be acceptable?

Won't crank or won't start?

 

[mopar 3 B]

Won't crank or won't start?

Won't either. But them it has to have the ability to crank to start..

 

[Stevecurley]

How you make an AGM fit Dennis..
View attachment 862881 View attachment 862882 View attachment 862883

Ever consider using a non clutch fan or adding an electric fan to the front side? Reason I ask is if your particular car has an automatic trans and your not running an extra trans cooler it would benefit the entire trans at all times to add an electric fan. These muscle cars tend to over heat a lot (they always did even back in their day) causing serious damage to the metals in auto transmissions to the point of scoring, cracking, breaking and blowing up. Hate to see a numbers matching 727 turned into scrap metal. I got lucky on that big block black Coronet, only broke an internal band fork from heat as the broken part fell into the pan area and stayed there.

BTW, pretty cool battery trick

 

[Stevecurley]

DO NOT trickle charge an AGM. Kill it partially if need be and then hit it pretty hard with 14+ volts to charge at about 8 amps. No need to maintenance charge a good AGM.

Ford telling me that my 2 year old battery in my F150 is good today.. even though within 2 days of charging my auto stop/start won't work because the truck knows it's charging the battery. Tech put it in their fangled tester and it showed 12.23 volts and drew only 379 CCA on it's 760 CCA rating. Charged it and then it tested fine.. even though I've done this twice myself they wouldn't give me a new battery. I booked an appointment for next Friday so they could do it again... lol I have prepaid maintenance and these f'rs are going to learn a lesson or three.

A freshly charged battery should read in the 13.2 / 13.6 range. A good one sitting for a bit at least 12.6

Apparently someone at the factory hijacked your heavy duty powerful beefed-up battery, "Where's the beef" went the commercial. Or they only last two years for that application.
https://www.cjponyparts.com/resources/auto-start-stop-explained
The auto stop-start function relies on a series of beefed-up internal components that you would find in any other vehicle. The battery and the starter all have to be as powerful and as durable as possible in order to restart the engine of the vehicle every time it is brought to a stop. There are no additional parts besides some circuitry that is necessary for an auto stop-start vehicle.

 

[Stevecurley]

Won't either. But them it has to have the ability to crank to start..

Interesting. It's like over the air digital TV, it's either all there or it's nothing at all.