How to revive dead car battery?

It may have a shorted cell, which will cause the others to discharge into it. If so, it's junk. Buy a cheap 4 ball hydrometer at the local parts deal. A shorted cell will show no balls(whatever...)while a low cell will float a couple-3. If all cells float some, it's still savable, and prolly just sulfated. You can sometimes cure this for a while by deep charging for several hours with a powerful charger, that can pump

30-40 amps c> Hello..

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After a number of years, usually about 4 to 5 years, the plates inside of the car battery get eaten away from the acid, and the electrical activity. The fix is to replace the battery.

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JANA _____

I hope this post is related to this group because I think this is about electronic a little bit.

Hmm, my car battery is almost dead. But, when I jumpstart it, it starts well and the battery is also okay for another 2-3 start after running it a while. Then, the next morning the car battery is flat out. So, is there any method for me to revive the dead battery? Because I think it is not fully dead yet, if I throw it, it would not be good to the environment.

Thanks.

harore

Sounds more like a shorted diode in the alternator or a light or a device of some sort is not shut down overnight. I would measure the current draw on the battery with everything shut down. Only a few milliamps is normal, battery backup for computer memory, anything more like an amp or more means a light is on somewhere, more than that would be a Shorted Diode in the alternator.

Yukio Yano

Usually when batteries fail like this, it's getting to be towards the end of the line for them. For sure, they can sometimes be 'rescued' by the sulphation reversal techniques and so on that have been proposed, but with winter coming on, do you really want to risk being out in the middle of nowhere, with a dead battery ? My last one failed after showing no signs at all, and after having just started the engine 10 minutes before without so much as a squeak of complaint, so I would take your symptoms as a sign of impending failure. Do the test of how much current is being drawn with everything 'off', as Yukio suggests, and if that is ok, just go ahead and replace the battery. There is no need to have any concern about the environment if you dispose of it at a proper centre, as there is a very robust recycling initiative in place for them in most countries.

Arfa

A shorted cell won't discharge the rest of the battery.

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"Arfa Daily" wrote in news:khrHi.7632$ snipped-for-privacy@newsfe7-win.ntli.net:

There is no

In the US,most places that sell new car batteries accept old batteries for recycling,and they usually have an extra charge if you DONT return the old battery,as an incentive to not dump it.

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Jim Yanik
jyanik
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Many places that replace car batteries will test your battery and charging system for free or for a small fee. It's worth the time to make sure a new battery wwon't be killed by a faulty alternator.

I know this is going to sound dumb, but I had this problem once and when I took it to a mechanic, it turned out to be a loose alternator belt. He told me that and I didn't believe it and said so. The belt wasn't making any noise and didn't slipping belts squeal?

He tightened it up and told me, "Look, I won't charge you anything. You drive it this way for a week and if it doesn't work, you don't owe me anything, but if it does, you owe me $10." I went back a week later and paid him.

vey wrote in news: snipped-for-privacy@corp.supernews.com:

that is one courageous mechanic.

Returning and keeping such an honest man on your side is a wise choice,though.

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Jim Yanik
jyanik
at
kua.net

I replace mine after 5 years regardless.

First check your charging system, if that's working ok, replace the battery. There's no way to restore it that will get you anything approaching reliable performance from it.

With the exception of giving a sulfated battery a good charge... there is no practical way to revive a battery.

However"

The battery is not necessarily bad... the problem could be your alternator.

With the engine running, measure the voltage on the battery... it should be approx 13.5 - 14 volts.

If it's under 13 volts...get it to a repair shop and have the alternator checked.

However, if the voltage is OK then the battery is either bad... or else there is a current drain somewhere.

You could try disconnecting the battery overnight to test that.

BTW: If it turns out that the alternator was bad... if the battery is not that old...once the car has been driven for a while and the battery is re-charged properly... it will be "revived".

Long since dead, I'm afraid. They don't make 'em like they used to.

I had a pair of Die Hards in my truck for 17 years. They were manufactured in 1980 though. Finally failed 10 years ago. They really don't make them like that any more.... Lenny

Good advice. I knew how to fix cars, and just went to Sears to buy a battery. I had just gotten the car from my brother and this was my first step in fixing a long term problem. They said, Do you want our Free two thousand thirty-five point multicheck? I figured why not.

They confirmed I needed the battery and found a bad connection, a dirty one, where the + battery cable connected to the starter solenoid.

The car was 3 years old and my brother had bought it new. The dealer had, they said, replaced the starter, the battery, and the alternator each twice, but never found the problem. Then after 2 years, they told him his warranty had expired. Sears found it in 5 minutes.

It wasn't the end of my problems, but it was a good start. Whenever I left the lights on for a few hours after turning off the car, the connection would go bad. At first I took off the cable, used a knife to clean the parts, and tightened it up again. Eventually I learned to stick my arm under the car and just move the cable around the bolt a little bit. Once I was on my way to a date and the car stalled and woudln't start just as I was getting on to Lake Shore Drive. In my good clothes had it started in about 15 seconds without getting anything dirty but my hand a little bit.

This was a 65 Catalina. The 67 Catalina didn't have this problem even when the lights were left on. Maybe I should have replaced the battery cable. maybe there was something strange about it. Or even the solenoid, but that's more work and money. Once I only had to wiggle it

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In addition to waht they said, a short term remedy is to disconect one pole of the battery every night.

Besides a lightbulb that is on all the tiem, you could have sonar in your burglar alarm, and once I accidentally installed two burglar alarms. The second made a difference, and ran the battery down efveyr night. It was an old battery, but even if it were new, it's not good for the battery to run it down everynight.

My first car, a 50 Olds, had a dead battery, adn all I had was a cord that plugged into the wall, a lightbulb socket with lightbulb, and an icepick. Even that would have been plenty, but just as I was about to find the problem, I would get something out of the glove compartement and shut the door well. On the way up, when I was almost "to the top", I would get something else out of the glove box and shut the door badly. Took extra hours but I found it, and bent the door a little and all was well.

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