A battery question

[Tinster]

I've recently had problems with a weak/dead battery.

Something hit me in the head last night.
The electric tester usually gives me 10 volts
stored in my battery. It is a 700 amp model.

I think the battery should have 12 volts.
Is this correct?

Maybe since my car usually breaks down after just
a few miles driving, the battery is not getting recharged
from the starter yanking out power? Also from me starting
the car and then turning it off.

So maybe little by little the amount of power stored inside the battery is going down.

Does this make any sense? I purchased a quality battery
and I think it's only about 18 months old.

I'll try and start the car again this afternoon.

thanks,

d

 

[Brosky]

Dale,

A battery needs a long steady and constant charge to bring it back from the Crypt, in a manner of speaking. Even if you use a commercial shop type charger. Your driving habits generally drain more than is ever put back in 10 minutes of idling or 5 miles of driving, so it's a long, steady, but slow decline (because your battery was new). It may come back after a good charge with a charger that can get the proper voltage and amperage back in or it may just be gone.

There is a certain amount of sulfate that can build up on the plates and this will resist a "trickle" type charge unless it's for a long time. The only way to know, if you don't have access to a long charge on a commercial battery charger is to try for 24-36 hours and then take it to a shop to be load tested. It will either be good or it will drain right down and not come back.

 

[Tinster]

Really an EDIT:

I rehooked the trickle charger so it put
36 hours total into the battery.

I just now read 12.4 volts with the electric tester.
I quess the 10 volts was not enough to start the car.

Gotta run errands for a while.
I'll attempt to start and drive the car later
today. Hope I don't get another breakdown!



d

 

[PeterK]

A battery maintainer such as the Delran model https://www.batterystuff.com/battery-char...;id=BT-021-0128 is the best for your battery. You can leave it hooked up (it even comes with a wire harness and quick plug) and it won't hurt your battery by over charging, like a trickle charger will. This is my favorite model and I use them on all the cars that don't get driven regularily. You MUST first have a fully charged battery, it is NOT a charger but will maintain it properly.

 

[Geo Hahn]

At 10 Volts (possibly for a long time) I wold consider this battery toast. You say it is a quality battery so presumably it has a long guarantee period.

You might take it back to the place you got it, have them test it and likely you will get a substantial credit on a replacement. A look on your face of 'I can't imagine what happened' is nice.

Once you have the replacement consider the advice on maintenace charging if the drive time will continue to be limited.

 

[Geo Hahn]

...put 36 hours total into the battery.

I just now read 12.4 volts with the electric tester.

Be aware that the voltage you get right after disconnecting the charger is rather meaningless, you have to use the battery just a little bit (or wait awhile) to get the real result.

 

[Brosky]

Dale,

A good, fully charged battery should read from 12.8V to 13.5V. Either charge it more, or I fear that it will not pass the load test. Maybe the charger can't give it more. I have a small Sears unit that I paid about $49 for and it works great.

 

[TR6oldtimer]

Dale, a voltmeter will not tell you the true condition of the battery, so I recommend you get one of these, they cost around $10. The hydrometer will check the specific gravity of the liquid in the battery. As the battery takes on a full charge the specific gravity will increase as the sulfates move into suspension. A heavily sulfated battery will give a voltage reading indicating the battery is charged, but when you test with the hydrometer you will see it is not.

If you have a sulfated battery, charge at 14.5 volts for a few hours, periodically testing with the hydrometer until charged.

 

[Tinster]

Thanks for the advice. Now remember where
I live. I don't have all the options you folks
Stateside have.

Western Auto - no chragers of any kind.
Pep Boys - no chargers of any kind.
AutoZone - only one model, only one unit in store,
I purchased it.

Here is what I purchased: I've hooked it up again
and will see what happens. It has a function for
defective battery and that function reads OK.
The yellow charging light is still lit. I pulled
the wires off before the green fully charged light
came on.

Another deluge of rain day so no driving Crypty.

d

 

[Brosky]

How about a Sears? I thought that you had one there?

 

[TR3driver]

Dale, the "defective" light only detects certain problems, so it not being on doesn't mean much.

From what I can see of the front panel, that unit only puts 1.5 amps at best into a heavily discharged battery (and 10v open circuit is heavily discharged). At that rate, it will take it several days to bring the battery up, if it can. But since that's what you have, my suggestion is to hook it up and leave it for 48 hours, see what happens. If the battery is badly sulfated, that charger probably won't help (but will go into float mode almost immediately).

Yes, driving with low battery voltage can cause all sorts of strange problems. With points the degradation is fairly gradual; but with an electronic ignition it can be fairly sudden. I limped home with a dead alternator on the Stag once, and the engine was still running fine less than a mile from my house, but started coughing and bucking about 3 blocks away and died totally before I got home. (Didn't quite have enough momentum to make it all the way into the driveway, but close enough.)

But, if it runs OK at first and gets worse due to low voltage, then there is also a problem with your charging circuit. With a healthy alternator, you can drive with no battery at all (as long as you keep the revs up). (NOTE : I do NOT recommend this, it's just to illustrate a point.)

Easiest test, IMO, for a battery is to use it to power the headlights for a few seconds (after charging) and then check the voltage with the headlights off. Should be very close to 12.6 volts. That doesn't prove it's at full charge, but says it's over 50% or so, which should be good enough. And a badly sulfated battery will not pass this test.

Ray's hygrometer is good too, but most batteries these days are sealed, which makes it hard to take a sample of the electrolyte from each cell.

 

[Tinster]

Dale, a voltmeter will not tell you the true condition of the battery, so I recommend you get one of these, they cost around $10. The hydrometer will check the specific gravity of the liquid in the battery.

<span style="color: #990000"><span style="font-size: 17pt">BLARGH!!!!!!!!!!!!!!!!</span> </span>

<span style="color: #990000">Western Auto had one of them gizzmos. Must be for
a city bus 'cause it sucked all the acid out of the firts cell and
came nowhere near the test level line. Got freakin' battery acid
all over me, my new shorts and the engine compartment.

Yes, Paul, we have a Sears. But it is a port of last resort
due to it's location. I'll keep on charging since it's
at 13.4 V after 5 additional hours.</span>

d

 

[TR4]

Didn't mean to, but I laughed out loud..........sorry.

 

[tomshobby]

Seems like Dale could use some battery safety help.

 

[Tinster]

<span style="color: #000099"><span style="font-size: 17pt">TOTALLY DISCOURAGED !!! </span> </span>

<span style="color: #990000">13.2 V and the car started fairly easily
with normal, rapid cranking of the starter.

Drove 0.8 miles in the hood for safety.... and the BLARGH!!
the engine stumbles and falls apart at 2000 rpm just
like it did when the condenser blew up. Barely could crawl
back into the crypt.

Most discouraging, indeed.

d</span> :madder:

 

[Brosky]

This on going saga could be made into a feature length movie and even then, no one would ever believe it.

Not even Fox Mulder and he REALLY wants to believe...........

Didn't someone post that these things are great for transferring battery acid to your tool box?

 

[Tinster]

<span style="color: #660000">so much time, effort and major $$$$$$$$.....

for so few miles driven.</span>

And my hands are both on fire from battery acid!

When does the FUN part begin???

d

 

[martx-5]

Dale...what you've been going through IS THE FUN PART.

What does the battery voltage read now that you're back home? Maybe that sucker is toast.

 

[Tinster]

Dale...what you've been going through IS THE FUN PART.

What does the battery voltage read now that you're back home? Maybe that sucker is toast.

<span style="color: #660000"> 12.8 V after starting the car, warm up and
driving 0.8 miles at under 2000 rpm.

Are condensers ever bad right out of the box?

d.</span>

 

[Brosky]

You don't have another "live ignition system" do you?