Dead/ shorted battery cell

4

46woodie

Senior Member
Batery is only couple years old and has always started car instantly. Go out this weekend and all I have is buzzing at solenoid. Bat reads 6.3V at terminals. Retightened all connections but no change. Tried rocking car thinking solenoid stuck,still nothing different. Bat will not take charge with bat charger. Any ideas,thanks!
 
6.3v is a pretty good reading for a 6 volt battery. If the solenoid is chattering when you try to start it, it may indicate a dirty connection, not getting full battery voltage to the starter.
 
When a cell in a battery is shorted (6 or 12 v) and a load is put on it like trying to turn the engine over, the cell will bubble profusely. Usually takes 2 people to check this and it has to be a battery that has caps you can remove. I had a brand new battery that wouldn't start my car and an old timer showed me how that worked. Of course this was after I replaced the battery cables and solenoid and rebuilt the starter. My first experience with New does not equal good. Of course, you would wear safety glasses doing this but it only makes little bubbles, it doesn't shoot out.
 
A shorted or "reversed" cell is going to be quickly evident by the open circuit voltage alone, it's kind of a diagnostic. In a 12 volt battery it will show 10.5 volts, or near enough. Simple arithmetic, a 6 volt battery would have a similar reduction, in proportion. Have to first remove any surface charge, to make meaningful comparisons because a battery recently charged will be artificially high. A load test will also tell the tale, though modern conductance type testers should quickly show this defect.
 
deuce_roadster said:
When a cell in a battery is shorted (6 or 12 v) and a load is put on it like trying to turn the engine over, the cell will bubble profusely.
Click to expand...

I used to work for a battery manufacturer in the US and did customer training sessions as part of the gig. I also did battery autopsy for Delphi.
I've never heard of that procedure before.....
 
Quote I used to work for a battery manufacturer in the US and did customer training sessions as part of the gig. I also did battery autopsy for Delphi.
I've never heard of that procedure before.....Quote

1948F-1Pickup,
Saw it with my own eyes, when my old retired machinist told me to look in the battery while he turned the key.

He told me that during the depression he made a stand that would hold a "bad" battery upside down and he would take a garden hose and kink and unkink the hose to pulse into each cell to flush it out. Then he would put new acid into them, and he said most came back to life and held a charge and he would then sell them!
 
While maybe it doesn't happen often, it isn't exactly unknown for batteries to (sometimes) explode under certain conditions, consequently sticking my face in the way of a battery with a possible shorted cell while cranking under load isn't something I'd be inclined to do if I could help it. Hydrogen + sparks is bad stuff.
 
deuce_roadster said:
Quote I used to work for a battery manufacturer in the US and did customer training sessions as part of the gig. I also did battery autopsy for Delphi.
I've never heard of that procedure before.....Quote

1948F-1Pickup,
Saw it with my own eyes, when my old retired machinist told me to look in the battery while he turned the key.

He told me that during the depression he made a stand that would hold a "bad" battery upside down and he would take a garden hose and kink and unkink the hose to pulse into each cell to flush it out. Then he would put new acid into them, and he said most came back to life and held a charge and he would then sell them!
Click to expand...




This method is absolutely correct. I've seen this hundreds of times in my job as a mechanic since the early '70s. One cell can short only under load and that short will boil that cell. Is it dangerous to observe...sure it can be. A face mask is best, and a mirror can be used as well.

As for the original poster's problem, I'd suspect a battery with a broken grid connection inside. Those batteries will check proper voltage at rest but when loaded will go "open" or nearly so, and will act like a nearly dead battery, only to check at normal voltage when unloaded again. Best way to find this is to have a volt meter hooked up and check voltage while trying to crank the engine. A broken internal connection will drop voltage immediately...usually to 30% or less, then return to full voltage when load is removed.
 
deuce_roadster said:
Quote I used to work for a battery manufacturer in the US and did customer training sessions as part of the gig. I also did battery autopsy for Delphi.
I've never heard of that procedure before.....Quote

1948F-1Pickup,
Saw it with my own eyes, when my old retired machinist told me to look in the battery while he turned the key.

He told me that during the depression he made a stand that would hold a "bad" battery upside down and he would take a garden hose and kink and unkink the hose to pulse into each cell to flush it out. Then he would put new acid into them, and he said most came back to life and held a charge and he would then sell them!
Click to expand...
Interesting. I’m guessing with the folks I worked for that that info was not shared for liability reasons. I’d only look “into” a cell with a camera remotely….. given some of the things I’ve experienced under hood over the years.

The other procedure of flushing and filling I’ve heard of before. The re-birth of the WWII Delco aircraft batteries that were at the bottom of the ocean, comes to mind.
 
Turn the headlights on and then hit the starter - headlights go very dim - bad battery. Buy an Optima and forget the lead acid battery.
 
Crankster said:
Wait, what?
Click to expand...

Was featured in a Hot Rod Mag article a number of years ago.
A number of reclaimed WWII Delco batteries from the bottom of the ocean were cleaned up, recharged and brought back to life. I think they were being displayed at the Smithsonian..... powering lights or some such stuff.
 
For an aircraft battery to survive even a few years under water it would have likely been sealed with no electrolyte in them otherwise they would be completely sulfated after just a year or so. Add salt water to a vented battery and it would be toast.

Automotive hard rubber case batteries from back in the day (the tar tops) could be opened up and rebuilt with a pack of new plates. This was common back then but the practice stopped in the early 1960s due to modern plastic cases being less expensive to manufacture but impossible to rebuild after final assembly.

All a person needs to find a dead cell is a hydrometer. Apply a charge to the battery and all three cells should improve in specific gravity. If one doesn't then it's dead. Flushing batteries in the modern era would be a waist of time in most cases due to sulfation or poor condition of the lead plates. A lot of modern batteries have small interconnect bars between cells and they can deteriorate as well. The quick way to test them is a load test but I haven't seen a 6-volt load tester in a long time.

Turn on the headlamps and engage the starter for a moment. If the headlamps go dim and then come back bright then it's likely the starter dragging or a problem with power or ground cables. If the lights stay dim after a start attempt then it's most likely the battery. This is a poor man's load check.

A sulfated or cell depolarized battery that has set too long can sometimes be brought back to life but a person should use a dumb 2 to 3-amp battery charger to charge it while maintaining electrolyte levels. Monitor the charge if possible with a clamp meter until it will take and hold a current rate from 2 to 3-Amps. This could take a week or more on a severely sulfated battery. Once it will hold a charge rate and has a voltage level that is normal for the voltage rating of the battery then a person has to cycle it with an appropriate load draw for the voltage rating. draw it down and charge it back up until it will hold a draw of around 100 watts for a good period of time for 6-volt batteries. If it will do that then it could be top charged and tested in the car. It will never be 100% but it may still work for a while.

A battery should be cycled at least every two weeks in service. If you let it set longer than that then it will sulfate back up sooner than you think. I consider starting the car and letting the battery charge completely back up to be a cycle.

Smart chargers are good as long as they stay smart. When they malfunction, they will do more harm than good. I always wonder how long some of these off shore products will last. How often should they be checked? I find it easier to check the battery by just starting the vehicle and running it for a while.
 
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Would suggest you go to Harbour Freight,if possible, and purchase a battery tester that will put a load on it. Cost about 25 smackers.
 
Woodie Guy, Would suggest just go buy a battery tester that will put a load on it.If by chance you have a Habour Frt in area, they cost about 25 smackers. I find it a good investment.
 
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