Excessive battery terminal corrosion

Kestas

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My car has developed corrosion on the positive battery terminal. The problem is that it seems excessive and needs cleaning more often than I can remember. I've had this car for 15 years. I normally don't bother with terminal coatings or felt pads, but I may have to with this car. It's a Durolast battery. What could have changed with my car to enhance this corrosion?
 
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7,061
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The Midwest
ONE cause could be micro cracks around the battery post in which gas is escaping and causing the issue. Usually caused by improper handling.
 
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Location
Toronto, Canada
I used to service a 1998 GM G3500 diesel van with a second frame mounted battery under the van and it always had a lot of corrosion on the positive terminal and I had to clean it every few months. The three other battery terminals on the van were fine. This corrosion persisted over the life of the van, through multiple battery replacements, from multiple battery sources - Delco, Costco etc. The experience seemed to rule out the usual causes - overcharging and cracked case around positive post
 

JHZR2

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New Jersey
In no particular order: 1) you clamped the battery too hard/right, and compromised the plastic to metal seal slightly. 2) age has worn/removed the protective coatings from the cable. 3) dirty/bad ground, including on the voltage regulator, causing more time at elevated voltages where gassing may occur. 4) bad/failing/intermittent diode that turns the alternator from a six pulse rectifier (terrible dc) to a four pulse (even worse). 5) poor quality battery 6) too cold at too low a charge at some point compromised case slightly I always put a thin coat of dielectric grease around the metal to plastic junction and on the terminals, and then spread the grease on the top of the terminal to coat the top of the cable clamp.
 

JHZR2

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New Jersey
Originally Posted By: George7941
I used to service a 1998 GM G3500 diesel van with a second frame mounted battery under the van and it always had a lot of corrosion on the positive terminal and I had to clean it every few months. The three other battery terminals on the van were fine. This corrosion persisted over the life of the van, through multiple battery replacements, from multiple battery sources - Delco, Costco etc. The experience seemed to rule out the usual causes - overcharging and cracked case around positive post
If the parallel batteries weren't perfectly matched and replaced in pairs, all sorts of funny stuff could happen.
 
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Upstate NY
Your battery is a leaker. The seal between the case and post was damaged. Felt pads may help. Aside from it being a PIA to keep clean it does does hamper the battery being a battery.
 
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Kestas

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The Motor City
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Originally Posted By: JHZR2
2) age has worn/removed the protective coatings from the cable.
This is on my 1995 Mercedes E320. The terminal head is brass, same shape as the thick lead ones. I can't remember if it ever had a coating. After two months, the corrosion was so thick the battery brushes couldn't remove it, and I had to scrape it off like a dental hygenist.
 
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North America
All good info above....add short tripping to the list of things that can cause the condition. If the integrity of the battery case is good then gluing a penny next to the positive terminal will get the corrosion on the penny instead of anywhere else.
 

Kestas

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The Motor City
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I just checked how old my battery is... over 8 years old! I'm going on a long trip in a couple weeks. I'm glad I caught this. This explains why it recently takes just a bit longer to crank the engine before it starts. Hopefully a new battery will cure this ill.
 
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10,436
Location
Cincinnati, OH, USA
Originally Posted By: Donald
Who mfg the battery? Exide??
No, it's the awesome Johnson Controls leak fest! I had one that leaked from DAY ONE with never having a clamp put on it (dual terminal battery).
 
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Messages
202
Location
MI
Most batteries made by East Penn (Sam's club Duracell, Napa, Meijer powercell, or Deka) have sealed tops and side vents that severely cut back on gassing and build up on terminals. Use plenty of cleaner and neutralizer and follow up with neutralizer coating or dielectric grease. If possible, a nice bath in some hot water and baking soda will help to clean and neutralize most of the acid. Make sure you really cover any exposed copper to cut back on green/blue copper sulfur corrosion.
 
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Location
Houston, Texas
Originally Posted By: Kuato
All good info above....add short tripping to the list of things that can cause the condition. If the integrity of the battery case is good then gluing a penny next to the positive terminal will get the corrosion on the penny instead of anywhere else.
Does the penny have to make contact with the post?
 
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Location
Central Maryland
Originally Posted By: Donald
Your battery is a leaker. The seal between the case and post was damaged.
This.
Originally Posted By: Kestas
I just checked how old my battery is... over 8 years old! I'm going on a long trip in a couple weeks. I'm glad I caught this. This explains why it recently takes just a bit longer to crank the engine before it starts. Hopefully a new battery will cure this ill.
Yes. I've seen this multiple times. When the green fuzz grows crazy fast, the problem is a leaky battery, and a new battery is the real fix.
 
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1,797
Location
San Antonio, TX
This happened to my sisters car. Duralast battery with excessive amounts of corrosion. Turns out it had a cracked case at the positive post. Autozone warrantied it. My dads motorcraft battery is doing the same thing but he won’t buy a new one. He’s gonna have to deal with bad terminals sooner or later.
 

4WD

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13,540
Location
Texas
Exactly the two cans I have … and they last a long time as I tend to do it at oil change time only and they stay corrosion free year round …
 
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8,456
Location
Virginia
At 8 yrs old that battery has done rather well. I think you are right on in replacing it before a trip. Very wise indeed.
 
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