Dead battery sound with full charge

[Tgriffin91 27]

Hi all. I finally have the mustang running and almost back on the road. Just one issue. When I go to start it I get the dead battery grind sound. I checked the battery several times and it reads 12.2V. As soon as I hook it up to my truck for a jump it goes to 14V and fires right up.

Why isn't 12V enough to start my car? Any ideas?

Engine is a standard 302 transmission is C4 both original to car.

[1969_Mach1 333]

Battery might have a shorted cell.  It should be load tested.  I think standard battery voltage is 12.6V since there are 6 cells and each cell is rated at 2.1V.  Anyway, first thing would be load test the battery. 

[Guillaume69 150]

You could go and have it tested by an automotive shop (Advanced and the likes). As 1969_Mach 1 says, chances are there's a shorted cell. The voltage is a little low (mine reads 12,7v on a fairly new Optima), and you might find out that your battery is no longer delivering the amount of CCA (Cold Cranking Amps) it is rated for. I had that happen to me not too long ago.

 

Slightly off topic but I also learnt - the hard way - that one should not store a battery on a concrete floor. Concrete has a negative charge (if I remember well) which will draw energy from a battery and eventually kill it.

 

G

[fordguy69 24]

Check your grounds.  Engine to frame, battery to frame. Insufficient grounds can cause this problem. 

[Midlife 814]

You could go and have it tested by an automotive shop (Advanced and the likes). As 1969_Mach 1 says, chances are there's a shorted cell. The voltage is a little low (mine reads 12,7v on a fairly new Optima), and you might find out that your battery is no longer delivering the amount of CCA (Cold Cranking Amps) it is rated for. I had that happen to me not too long ago.

 

Slightly off topic but I also learnt - the hard way - that one should not store a battery on a concrete floor. Concrete has a negative charge (if I remember well) which will draw energy from a battery and eventually kill it.

 

G

Sorry to be a mythbuster....

http://www.snopes.com/autos/techno/battery.asp

http://www.cartalk.com/content/business-batteries-and-concrete-floors-needs-be

http://www.homepower.com/articles/solar-electricity/equipment-products/ask-experts-batteries-concrete

[Brian Conway 264]

These are the not running 12.66 and running/charging readings 14.26 from my car/battery. Your test results should be similar. Interesting reading about concrete floors and the head pictures are not mine. Brian

[Guillaume69 150]

Well, Randy, a very serious welder friend of mine explained me that stuff. I might need to read more about it though, but let me tell you that my nice "Autolite" died after one winter on the garage (concrete) floor. Or may be it's because those are expensive POS?

 

NPD refunded the second one when it died too after 6 months in the car.

[1969_Mach1 333]

Actually I heard about the setting a battery on concrete issue back in high school shop class.  Never fully understood why.  If its what Guillaume69 mentioned or the cooler concrete surface slows down the chemical activity in the battery.  End result is still the same, dead battery.

 

I've had several batteries appear fine but have slightly low open circuit voltage and the starter won't crank or cranks slow.  When load tested a bad cell would show up.

[det0326 179]

Always load test battery when this problem arises. A battery does strange things sometime, I had a couple in my life time to be cranking the car one minute and nothing the next minute. Had an internal open circuit and it happens especially if the battery has been abused from an ill cranking car.  Putting enough load on it would cause it to open.

Dave

 

not my pic's, good info tho for those who don't have those dimensions.

[Midlife 814]

Well, Randy, a very serious welder friend of mine explained me that stuff. I might need to read more about it though, but let me tell you that my nice "Autolite" died after one winter on the garage (concrete) floor. Or may be it's because those are expensive POS?

 

NPD refunded the second one when it died too after 6 months in the car.

Maybe because those batteries tend to die in a year or so, regardless of where they are placed?

 

I've always placed batteries on wood planking shelves because I almost always end up stubbing my toes on the damn things!

[danno 128]

All batteries will self discharge over a period of time, it has nothing to do with sitting on a concrete floor.  Sit it on a pile of bullsh**, and it will discharge the same. It discharges itself through the plates in a chemical reaction, think of it as a very weak connection between the + and - terminals, inside the battery. Cold slows the self discharge.  It is more obvious in lead acid batteries of a car, but even alkaline batteries will self discharge over a period of years. No magic of concrete, just reality of chemistry.

[1969_Mach1 333]

Sorry to be a mythbuster....

http://www.snopes.com/autos/techno/battery.asp

http://www.cartalk.com/content/business-batteries-and-concrete-floors-needs-be

http://www.homepower.com/articles/solar-electricity/equipment-products/ask-experts-batteries-concrete

 

My thoughts and what I was taught is the cooler temps from the concrete slows the chemical activity inside the battery.  Then every time a lead acid battery goes dead, a solid sulfur substance (I don't know the chemical names and formulas) forms on the plates starting from the bottom of the battery and slowly moving upward.  Slowly recharging the battery will break down some but usually not all of this sulfur material.  Over time the surface area of the plates diminishes and reduces the amperage capacity of the battery until it needs replacing.  That's why items like Battery Tenders that maintain a battery charge without letting it drain increase the battery life on cars that are rarely driven.  A drain and recharge cycle is one of the worse things that can be done to a battery. 

[Tgriffin91 27]

Always load test battery when this problem arises. A battery does strange things sometime, I had a couple in my life time to be cranking the car one minute and nothing the next minute. Had an internal open circuit and it happens especially if the battery has been abused from an ill cranking car.  Putting enough load on it would cause it to open.

Dave

 

not my pic's, good info tho for those who don't have those dimensions.

This could be it. From cranking the car when I was still having electrical issues. I'll get it tested sometime soon and let you all know. Sparked quite the debate. Just FYI this battery has not sat on a concrete floor for more than a day at a time.

[Tgriffin91 27]

Got the battery tested today and it tested all good. Next I'll look into grounds and make sure those are tight.

[j69302 11]

I had a perfectly good Interstate battery that I left on the garage floor over night while I cleaned up and replaced my battery tray.

 

Next day, it was dead. Wen't from 12.5 volts to low 10's. It would take a jump, start, and run, but would never charge. Each time I shut it off, it needed another jump an eventually it came to the point where it wouldn't jump at all even with a good 14+ volts from the jumping vehicle.

 

In the aviation world, we are told not to put batteries on the ground. Must be on a bench, prefferrably wooden. Also can't mix tools from one type of battery, to another, example, using tools on a nicad battery then using the same tools on a lead acid.

 

I had to replace that battery.