Ok, so a while ago I posted that my car wouldn't start. I was leaving for Iraq, so I didn't have time to really check it out. I feared the worse. All the lights would come on and it would turn over, but not start. It sounded funny too. So my dad takes it to a local mechanic the other day and he gets it started in a day. The problem (here's where KISS would have worked) dead cell in my battery. That's all. It's been running fine since. I'm relieved, but a bit disgusted. Oh well. I guess all four rotors siezed, so I got new rotors installed. Now I can't wait to get back and drive it. On a semi-related note, would a bad alternator have caused the battery issue?

 

>I'm an idiot

Welcome to the club.

A faulty alternator could cause a battery to die. If the voltage regulator in the alternator is faulty, it can overcharge the battery and can kill it. If the alternator is about to retire, it would stop charging the battery and can leave you stranded. This happened to me once.

A name brand battery is well worth the extra cost as compared to some cheap franchise brand batteries. I've been using the Interstate Battery. Also, you want to make sure that each cell (a total of 6) has sufficient amount of electrolyte. If the top of the plates are exposed, add some distilled water but be careful when you do this, as the electrolyte is strong acid and if it gets in your eyes, you're in a major trouble.

If only one cell was dead, the cell was probably short on the electrolyte. If all cells were dead, it was either the battery has reached its life or the alternator was not producing rated voltage (13.1V+). I would invest in a digital multimeter so you can check the general condition of the battery & the alternator. All you need is a $20-$30 Craftsman meter.


JPN

 

Autozone and all those other stores will test alternators for free.

 

Battery (or accumulator) cells are just like cells in the human body - they tend to die over time, albiet from completely different reasons.

Some of the spongy lead present in the electrolyte when being transferred from one set of plates to another, drops to the bottom of the accumulator, and over time builds up eventually shorting out some, or all, of the plates in that cell.

Once a battery (can you spot the clever use of both names?) has reached that point it is useless and should be dispensed with as any charging effect by the electrolyte on that cell is negated by the internal short. But, just to trap the unwary, sometimes a bodgy accumulator will show a reasonable voltage when tested with a multimeter making it appear O.K.

But don't be fooled!

Throw away your trusty, overworked multimeter for this particular job and arm yourself with a discharge tester, as this is the correct tool to use when checking a battery for a bodgy cell. Bang a current discharge tester on the accumulator and just watch the terminal voltage of the battery plummet if the cell is bodgy.

 

The KISS principal always comes into play when I have a vehicle issue. Not that I am a genius (I am definitely a charter member of the idiot society) but I always try to look for the easiest solution first.

 

A couple of guys, who are good mechanics, in my car club said that even with a dead cell, the car should have started. They think that a sensor may have been reset when the battery was disconnected, and that's why it is running again. Any thoughts? If there is much truth to this, I would like to check it out before I get stranded somewhere bad. Thanks all.

 

Volvo's are really fussy about voltage.
Had a 264 that was struggling to start, ran rough, everything else was fine.
Battery read 12.? with motor running.
Rebuilt alt fixed everything, started first crank, ran smoothly, charged at 13.?

Had a holden with a single dead cell, wouldn't even turn over.

 

They might know a bit about mechanics - but it would seem their electrical knowledge is slightly deficient.

 

Sorry, I initially missed this query.

The answer is not normally.

However, it can happen in odd circumstances where a diode malfunctions (e.g. internal short) and allows current to backfeed through the alternator circuitry to ground - which will discharge the battery fairly quickly.

 

Might not hurt to get the charging system tested.

 

+1.

A digital multimeter would suffice to test the alternator output. To test the battery more accurately, Volgrrr's advice is better. Basically there are 3 ways to test a battery:

- Multimeter test.
- Specific gravity test.
- Load test.

The load test is the most accurate way to test a battery, and I believe this is what Volgrrr was referring to.

To see if the alternator is working fine, hook up a digital multimeter across the battery; it should read 13.XV to 14.XV, whatever is specified by the mfg. If too low, it won't be able to charge the battery and if too high, it would fry some of the electrical devices. Some devices may be protected by fuses, while some others are not.

In case if you need to replace the alternator, make sure to have the battery fully charged before installing the alternator or the new/rebuilt alternator will be damaged. If you're unsure about the condition of the battery, replace it with a name-brand's battery (I would recommend the Interstate Battery).


JPN