corroding negative battery terminal... leaking battery, right?

Jayne

Jayne

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Cleaned a lot of corrosion off the negative battery terminal on my van, and in just a few weeks it's back again. Supposedly a 'sealed' battery, but I assume it's cracked and leaking which is what causes the corrosion to form?
 
No. Corrosion (usually white) on the negative terminal indicates low charging.

It's Sulfation, caused by battery not being charged enough.
 
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Jayne said:
Volt meter (after market) reads 14.1v almost all the time. So the battery isn't taking a charge, or the charging system is suspect?
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If this is when running, the alternator is delivering to the battery, time to test the battery as it probably isn’t holding. At least that’s what I believe.
 
when I worked for Toyota many moons ago, we would spray white lithium grease on the clean connections to seal out the elements...
 
Jayne said:
Volt meter (after market) reads 14.1v almost all the time. So the battery isn't taking a charge, or the charging system is suspect?
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The battery at rest with no load should be around 13V.
With the engine running, it should be around 14-15V.
 
My Rav4 battery would corrode 1 post every few weeks when I got it.

I’d clean it, put the little felt rings under it, spray it with battery terminal cleaner, spray corrosion preventative, then... 3 weeks later more corrosion.

Finally one day I noticed a crack in the top of the battery case right by the terminal. My guess is someone overtightened the terminal and it cracked the case.

The battery was a few years old so I got a new battery and have had no corrosion since then.

There are other causes (loose terminals, undercharging, materials, etc) but mine was the cracked case.
 
With battery tester and a volt meter, you can tell whether a battery or starting problem is being caused by the battery, the alternator or the starter. In this case, a battery tester will confirm the strong suspicion that the battery is not charging up fully. First, check the resting battery voltage. Then, use the load tester to see if the battery is holding a good charge.
 
Jayne said:
Cleaned a lot of corrosion off the negative battery terminal on my van, and in just a few weeks it's back again. Supposedly a 'sealed' battery, but I assume it's cracked and leaking which is what causes the corrosion to form?
Click to expand...

Not necessarily. Supposedly there are several causes.

If your voltmeter is showing 14 when motor is running your charging system is probly good.
If you cleaned the corrosion off and didn't put anything on terminals and connections to seal them from the elements, that "could" be why it came back so soon. You've got to really really get that crap outa there and I always do the baking soda and water mix afterwards to neutralize any remnants of corrosion that may be left behind.
Then I coat everything with dielectric grease, the terminal, connector, and any exposed wire at the connector, inside, outside, upside down before reconnecting the cable to the battery. This usually takes care of it.

On two different occasions, I have done this procedure and had corrosion return. I discovered that the corrosion had actually made it's way past the connector and up inside the cable. I replaced one just because it was a short run to the solenoid, the other I disconnected the battery and removed it to get it outa the way, made up a pint jar of the baking soda/water solution and got as much of the cable in it as I could. Wow you shoulda seen the reacting going on. Did this two more times until there was no more, put it all back together with ample grease on everything, no more issues.
I cut the insulation off the one I had replaced and the corrosion had run 4-5 inches away from the connector.

I tried the red stuff @LeeMajors mentioned with less than desirable results but a lot of folks use it.
Wheel bearing grease works well also.

Maybe TMI but just some cheap things to try before ponying up for a new battery that you may not need. Good luck.
 
Never purchase a new battery without first using your own battery tester to determine if it is necessary.

71Jsw-VGdUL._SL1500_.jpg
 
Northern tool often has their digital battery tester on promo plus the $10 coupon they send in the mail.
 
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I always take my batteries into walmart for testing. Nobody is ever there so I just put it in a shopping cart, rollup to the machine, hook it up, select the right program and let it run the full battery of tests.

if those portable testers are good that’d save me some time.
 
If one side constantly is corroded then there is a crack at the post seal.

Cause:
Top post - when strap carriers that attach to the posts are used. The posts are not designed to carry the weight.
Side Post - bolt was over torqued

Time for a new battery. :(
 
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I bet it is the seal at the terminal post going into the battery. The post is acting like a candle wick
 
Pink_Vapor said:
The battery at rest with no load should be around 13V.
With the engine running, it should be around 14-15V.
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At rest no load after driving ~80 miles today and sitting for 3 hours after.... shows it at 12.15 V
 
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Jayne said:
At rest no load after driving ~80 miles today and sitting for 3 hours after.... shows it at 12.15 V
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Sounds a little low.
PM sent & you can go to a AutoZone, Adv Auto, o’Reilley’s and have the charging/battery system checked for free. The ‘operators’ usually aren’t real knowledgeable, so the results can be off at times.
 
Jayne said:
At rest no load after driving ~80 miles today and sitting for 3 hours after.... shows it at 12.15 V
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That's way too low for a battery that should be at full charge.

One day, you will have a car that won't start. Then you will need a battery tester to determine if it's the battery, starter or alternator. After charging up the battery, the tester identifies the battery as the problem, or exonerates it. Get one now, and confirm that your battery needs to be replaced.
 
MacEntyre said:
That's way too low for a battery that should be at full charge.
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Yep, costco run tomorrow to swap it out. I have no idea if it's the original 2013 or not, I've only had the van for 1.5 years. It's an actual "ford" battery though, I can't imagine anyone buys those except when it's new... right?
 
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Jayne said:
Yep, costco run tomorrow to swap it out. I have no idea if it's the original 2013 or not, I've only had the van for 1.5 years. It's an actual "ford" battery though, I can't imagine anyone buys those except when it's new... right?
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The Ford factory batteries are not high quality.
 
Pink_Vapor said:
The Ford factory batteries are not high quality.
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I ran the original factory ford batteries from 2011 f250 in my truck till sept 18.

So it is possible its factory
Jayne said:
Yep, costco run tomorrow to swap it out. I have no idea if it's the original 2013 or not, I've only had the van for 1.5 years. It's an actual "ford" battery though, I can't imagine anyone buys those except when it's new... right?
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Pulled the battery and found what I believe is the date code, Oct 22, 2012 is consistent with the age of the van....

It's gone now, fresh one dropped in today. If this wasn't the problem it will become apparent in the next week. Sure starts 'faster' now in any case.

van_original_battery_replacement_2.jpg
 
I think this will fix it. You likely had both a leak, and that led to undercharging. That blue corrosion is copper sulfate and is usually from a leak. The white/gray corrosion on a neg. terminal is due to undercharging.
 
I had a Sears DieHard that lasted me seven years, I drove the car 150 miles a day round trip four days a week to NY City.
 
I was actually told yesterday by an Interstate battery guy. That corrosion comes from slightly overcharging
 
LeeMajors said:
I was actually told yesterday by an Interstate battery guy. That corrosion comes from slightly overcharging
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True, over charging leads to the acid expanding and act like it's boiling. That would tend to be a whole lot of acid, everywhere. The most common is leakage if it's located in a specific area.
 
I've been using the terminal felt washers at Walmart, USA made about $1 pkg. No corrosion on all five cars.
 
rdinatal said:
True, over charging leads to the acid expanding and act like it's boiling. That would tend to be a whole lot of acid, everywhere. The most common is leakage if it's located in a specific area.
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Indeed it does.

I recently had the voltage regulator go bad in the alternator on my articulated loader. 24v dual battery system. Totally fried two batteries that were a year old. My employees had been running the loader. I got in it to move it, smelled hydrogen and sulphate and then noticed that the ammeter was pegged at 39 volts. I shut it down immediately and bailed out in case the batteries exploded. Lots of fumes emanating from the battery compartment...

After they cooled down they had no voltage.

Definately got the stink eye look from the guy at the battery place when they were returned for warranty!
 
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