Cleaning Car Battery Terminals

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ThankYouJack
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Cleaning Car Battery Terminals

Post by ThankYouJack » Thu Jan 10, 2019 11:49 am

I replaced my car battery not too long ago but already have some corrosion on the positive terminal. I know it's common but I assume I should clean it sooner than later.

Any recommendations for tools, cleaner and grease to use to clean it?

Nissanzx1
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Re: Cleaning Car Battery Terminals

Post by Nissanzx1 » Thu Jan 10, 2019 11:52 am

Just mix up some baking soda and water and drizzle it on there slowly.

Or Coca Cola also works in a pinch.

There is a small metal tool that cleans these. $4 at harbor freight. Search Battery post cleaner and it should take you there.

neilpilot
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Re: Cleaning Car Battery Terminals

Post by neilpilot » Thu Jan 10, 2019 12:01 pm

If you remove the positive cable to clean the corrosion, then coat the clean terminal with a small amount of petrolium jelly and be sure to properly tighten the terminal clamp. Excessive corrosion at the positive terminal is a sign of overcharging, so you might also check the fluid level if your battery has removable cell covers.

BTW you should disconnect the negative (ground) at either the battery or the car connection before removing the positive terminal, and reconnect the ground after the positive has been reconnected.

btenny
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Re: Cleaning Car Battery Terminals

Post by btenny » Thu Jan 10, 2019 12:06 pm

Use an old toothbrush to clean the terminals along with water and baking soda or coke. Make sure the car is parked off your drive way on the dirt as the water dripping out from this process is dirty and caustic. Use a lot of water after everything is clean to wash off all the coke and baking soda. Then let the terminals dry. Then paint the terminals and all the exposed metal with a regular can of spray paint. Any color will work but black usually looks best. The trick is to cover all the metal so it does not corrode in the future.

Good Luck.

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Blueskies123
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Re: Cleaning Car Battery Terminals

Post by Blueskies123 » Thu Jan 10, 2019 12:06 pm

neilpilot wrote:
Thu Jan 10, 2019 12:01 pm
If you remove the positive cable to clean the corrosion, then coat the clean terminal with a small amount of petrolium jelly and be sure to properly tighten the terminal clamp. Excessive corrosion at the positive terminal is a sign of overcharging, so you might also check the fluid level if your battery has removable cell covers.

BTW you should disconnect the negative (ground) at either the battery or the car connection before removing the positive terminal, and reconnect the ground after the positive has been reconnected.
If you have a newer car and do this you might have to re-enter some codes to get your radio and windows to work so know what you are doing.
I use these:
https://www.amazon.com/CRC-05046-Batter ... st+cleaner
https://www.amazon.com/Battery-Anti-Cor ... st+cleaner
https://www.amazon.com/Schumacher-BAF-B ... st+cleaner

livesoft
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Re: Cleaning Car Battery Terminals

Post by livesoft » Thu Jan 10, 2019 12:08 pm

Any auto parts store, big box store will have a kit to do all this. They are all the same, so no recommendation is needed. Whichever one is cheapest which means including your time, gas, etc, probably Walmart or HomeDepot the next time you go to one. In fact, I don't bother as the white stuff really won't affect the life of the battery where I live and is more cosmetic than anything else.
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neilpilot
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Location: Memphis area

Re: Cleaning Car Battery Terminals

Post by neilpilot » Thu Jan 10, 2019 12:31 pm

Blueskies123 wrote:
Thu Jan 10, 2019 12:06 pm
neilpilot wrote:
Thu Jan 10, 2019 12:01 pm
If you remove the positive cable to clean the corrosion, then coat the clean terminal with a small amount of petrolium jelly and be sure to properly tighten the terminal clamp. Excessive corrosion at the positive terminal is a sign of overcharging, so you might also check the fluid level if your battery has removable cell covers.

BTW you should disconnect the negative (ground) at either the battery or the car connection before removing the positive terminal, and reconnect the ground after the positive has been reconnected.
If you have a newer car and do this you might have to re-enter some codes to get your radio and windows to work so know what you are doing.
When I disconnect a battery terminal, I often first hookup a battery charger in parallel or thru the cigarette lighter (assuming it's hot with the ignition off) to avoid losing the radio codes.

rkhusky
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Re: Cleaning Car Battery Terminals

Post by rkhusky » Thu Jan 10, 2019 12:35 pm

Nissanzx1 wrote:
Thu Jan 10, 2019 11:52 am

Or Coca Cola also works in a pinch.
Interesting that Coke works. I thought it was acidic, as opposed to basic like baking soda.

barnaclebob
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Re: Cleaning Car Battery Terminals

Post by barnaclebob » Thu Jan 10, 2019 12:49 pm

I used to have really bad corrosion on my positive terminals until I cleaned them and applied some of this stuff:

https://www.amazon.com/NOCO-CB104S-Batt ... prevention

No problems for several years now. I think i tried the felt washers first but there was still some corrosion with them.
Last edited by barnaclebob on Thu Jan 10, 2019 12:55 pm, edited 1 time in total.

barnaclebob
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Re: Cleaning Car Battery Terminals

Post by barnaclebob » Thu Jan 10, 2019 12:51 pm

livesoft wrote:
Thu Jan 10, 2019 12:08 pm
Any auto parts store, big box store will have a kit to do all this. They are all the same, so no recommendation is needed. Whichever one is cheapest which means including your time, gas, etc, probably Walmart or HomeDepot the next time you go to one. In fact, I don't bother as the white stuff really won't affect the life of the battery where I live and is more cosmetic than anything else.
Its not cosmetic, Its your clamp being slowly eaten away. Mine was eaten completely through and had to be replaced but it did take over a decade before that happened. That's when I started using the corrosion inhibiting compound I linked above...
Last edited by barnaclebob on Thu Jan 10, 2019 12:58 pm, edited 1 time in total.

JohnF
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Re: Cleaning Car Battery Terminals

Post by JohnF » Thu Jan 10, 2019 12:53 pm

Next time buy an AGM battery … no corrosion.

heyyou
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Re: Cleaning Car Battery Terminals

Post by heyyou » Thu Jan 10, 2019 3:24 pm

In retirement, I can spend a little time cleaning the terminals to avoid the extra cost of an AGM battery.
My first job away from home was at a "full service gas station" without a convenience store. I can explain what that was, to the younger BHs.

Teague
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Re: Cleaning Car Battery Terminals

Post by Teague » Thu Jan 10, 2019 3:28 pm

For Pete's sake put goggles (or something) over your eyes before cleaning the terminals. Battery corrosion has this almost magical way of winding up in one's eyes, and it's quite corrosive to the eye tissues.
Semper Augustus

Housedoc
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Re: Cleaning Car Battery Terminals

Post by Housedoc » Thu Jan 10, 2019 4:34 pm

Clean as everyone has said, coke or baking soda. Dry terminals and clamps and spray with a battery terminal/post spray available at auto parts store for a few bucks. Also wash area around battery box with a garden hose to wash away any corrosive material that may have worked its way onto another surface. You should be good to go if you removed all trace of acid.

Topic Author
ThankYouJack
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Re: Cleaning Car Battery Terminals

Post by ThankYouJack » Thu Jan 10, 2019 4:53 pm

Thanks all. Simple enough. I'll use goggles, gloves, and baking soda and pick up a terminal brush and some protective spray.

Broken Man 1999
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Re: Cleaning Car Battery Terminals

Post by Broken Man 1999 » Thu Jan 10, 2019 4:54 pm

Another vote for coke to clean battery terminals.

Recommended by BIL who is a Mercedes Benz Master Technician. Good enough for my Ford.

I imagine at the MB dealership there is some very special fluid that costs a fortune. :dollar :dollar

But, that's the way MB rolls. My Ford van doesn't have a sophisticated needs system.

Broken Man 1999
“If I cannot drink Bourbon and smoke cigars in Heaven than I shall not go. " -Mark Twain

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Blueskies123
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Re: Cleaning Car Battery Terminals

Post by Blueskies123 » Thu Jan 10, 2019 4:57 pm

JohnF wrote:
Thu Jan 10, 2019 12:53 pm
Next time buy an AGM battery … no corrosion.
Twice the price and it does not last any longer than a regular battery. Ask how I know.

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ClevrChico
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Re: Cleaning Car Battery Terminals

Post by ClevrChico » Fri Jan 11, 2019 12:07 am

Once clean, spray the connected terminals with Fluid Film. No more corrosion.

phantom0308
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Re: Cleaning Car Battery Terminals

Post by phantom0308 » Fri Jan 11, 2019 12:41 am

For acidic batteries like car batteries you should use a base like baking soda. Mix it with warm water so it dissolves faster.
For alkaline batteries like Energizer batteries you should use an acid. White Vinegar should work slightly better than Coke. It has a similar pH, but a higher concentration of acidic ions meaning It should react faster. I haven’t compared them though.

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baconavocado
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Re: Cleaning Car Battery Terminals

Post by baconavocado » Fri Jan 11, 2019 12:52 am

I clean my engine and under-hood area every 2 years at one of those self service car washes and this seems to take care of battery acid leaks as well.

nickjoy
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Re: Cleaning Car Battery Terminals

Post by nickjoy » Fri Jan 11, 2019 11:51 am

Go to any parts store and there is a battery terminal cleaner tool for about 2 or 3 bucks. You take the wire off it, put the terminal on it, then twist, the metal wires scrape off corrosion. If there are bad areas left, you can take the cap off the tool and there is a wire brush for you to get into those areas.

If you do this you won't lose any codes or radio programs. Unless you take an hour to do it.

If you do this, you won't have to buy a can of silver stuff and paint your terminals.

If you do this, you can lose the tool and just go buy another one for $3 and be in it for less than what other people paid and its a lot cleaner than toothbrushes and making baking soda pastes.

krafty81
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Re: Cleaning Car Battery Terminals

Post by krafty81 » Fri Jan 11, 2019 3:47 pm

I did not use goggles and got a little splash in my eye of course! Painful lesson learned! Rubber gloves too.

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Toons
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Re: Cleaning Car Battery Terminals

Post by Toons » Fri Jan 11, 2019 4:06 pm

Ditto
Gloves
Toothbrush
Brush with Baking soda.little water mixed in.
Dry off,
Vaseline.
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sport
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Re: Cleaning Car Battery Terminals

Post by sport » Fri Jan 11, 2019 4:25 pm

One other detail not mentioned yet. That white corrosion is an insulator. If it builds up between the terminal and the connector, the car will not start, until it is removed.
Goggles
Remove negative connector
Remove positive connector
Baking soda solution/brush
Rinse
Wire brush
Rinse
Grease (no paint, paint is an insulator)
Replace positive connector
Replace negative connector
Clean corrosive material from tools.

Grt2bOutdoors
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Re: Cleaning Car Battery Terminals

Post by Grt2bOutdoors » Fri Jan 11, 2019 4:32 pm

sport wrote:
Fri Jan 11, 2019 4:25 pm
One other detail not mentioned yet. That white corrosion is an insulator. If it builds up between the terminal and the connector, the car will not start, until it is removed.
Goggles
Remove negative connector
Remove positive connector
Baking soda solution/brush
Rinse
Wire brush
Rinse
Grease (no paint, paint is an insulator)
Replace positive connector
Replace negative connector
Clean corrosive material from tools.
+1 - I use automotive grease, but in a pinch you can use Vaseline if you don’t have a tube of grease handy.
"One should invest based on their need, ability and willingness to take risk - Larry Swedroe" Asking Portfolio Questions

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jharkin
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Re: Cleaning Car Battery Terminals

Post by jharkin » Fri Jan 11, 2019 9:13 pm

Blueskies123 wrote:
Thu Jan 10, 2019 4:57 pm
JohnF wrote:
Thu Jan 10, 2019 12:53 pm
Next time buy an AGM battery … no corrosion.
Twice the price and it does not last any longer than a regular battery. Ask how I know.
And AGM has nothing whatsoever to do with terminal corrosion or lack therof. AGM batteries have lead terminals the same as standard wet sealed car batteries. They also use the same internal chemistry, the only difference is the acid is suspended in a mat of fiberglass cloth.

The corrosion is typically a galvanic reaction between the lead terminal and copper clamp. Yes a real bad buildup could be accelerated by an acid leak but that could happen with any battery type.

sport
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Re: Cleaning Car Battery Terminals

Post by sport » Fri Jan 11, 2019 9:29 pm

The corrosion on the positive terminal is caused by electrolyte (acid) that leaks through the interface of the lead terminal and the plastic cover. The cover is molded with a lead insert (the terminal). The lead insert has a convoluted shape in the area where it contacts the plastic. This "tortuous path" is intended to minimize leakage through the interface, but sometimes the plastic does not seal tightly to the lead insert. When the acid gets onto the positive terminal, the charging current causes a film of lead peroxide (PbO2) to form on the surface of the terminal. This, along with the lead connector forms a little cell, which discharges leaving a film of lead sulfate (PbSO4). This film is an insulator and should be removed before it becomes thick enough to prevent the car from starting. The reason that this does not occur on the negative terminal is that when a battery is charged, the negative plates are converted from lead sulfate to metallic lead. Since the terminal is already lead, there is no further reaction.

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