Should I clean car battery terminals? and if so how?

[Stormin Mormon]

I clean it in place.

[Steve B]

The fastest/easiest way is not the best. Any soda pop can be drizzled on there, and it will cause some of the corrosion to be dissolved. But it does not get down into the terminals.

To clean terminals, you need a battery brush.

You must remove the terminals, and you must use two wrenches, one on each end of the bolt to keep from cracking off the whole terminal. Also, if it is severely corroded, you might break off the bolt. Once the cable is off, it can be cleaned with a battery brush until it is shiny. Special grease can be put on the terminals to keep corrosion down. Treated felt pads can then be put on the terminals before reinstalling the cables.

If you have green corrosion on your terminals, you are not far away from hearing the click click rrrrrrrrrrrrrrrrrr!

Pouring Coca Cola on there might buy you a little time, but they need to be cleaned RIGHT.

Steve

[hrhofmann]

If the battery is 3-4 years old, andfails after the lights are on for an hour, that is a warning that you should get to your local Walmart and buy a replacement battery!!!!!

[David Nebenzahl]

On 3/21/2010 7:02 PM Mikepier spake thus:

Second that emotion. Clean (and yes, baking soda is good to neutralize the acid crud), then smear ordinary wheel-bearing grease on it.

[David Nebenzahl]

On 3/22/2010 7:19 AM HeyBub spake thus:

Since the battery innards are acid, the crud is too.

Try it yourself: sprinkle some baking soda on a wet battery top and you'll see it fizz.

[Pavel314]

And be very sure to remove the ground terminal (black wire) first! If you work on the positive terminal first, you run the risk of shorting out if the wrench which is in contact with the terminal hits the engine block or body or some other grounded piece of metal.

Paul

[mm]

I clean it in place too. It's fine that way. Someone called attention to your subject line. I pay little or no attention to those and only look in the body of a post, but you did emphasize terminal in your first post too, yet I concentrated on crud.

If there is crud right on the terminal, right next to the where it touches the post, it might be under the terminal too. It's probably a good idea to remove the cables and clean the posts and inside the terminals too.

Remove the ground first. The one with a - symbol on the battery (not a + ). Now the symbols can be hard to see, and in all recent cars the plus terminal is the one whose cable goes to the starter motor or a solenoid. The negative terminal goes to a bolt on the engine. It's the negative, the ground, you want to remove first. This seemed counter-intuitive to me, but if your wrench touches the body of the car while you're working on the negative, nothing will happen. Then after the neg is disconnected and you are using your wrench on the positive, and your wrench touches the body of the car, nothing will happen. If OTOH, the negative was still connected, there would be a big hot spark, enough to melt metal, at least a small amount. So disconnect the ground, the negative, first. If you're not sure, there might be a label somewhere, or someone with a meter or who knows cars can tell you which is the negative.

If that doesn't work, clean the battery once without disconnecting it and then maybe you'll be able to see the + and - symbols, although they can be on the side where it's hard to get a good look, or obscured by the terminals.

[mm]

Yes, they used to be a dollar a pair. Maybe a little more now. I'm sure they have them at "real" autoparts stores but they have them on display usually at consumer autoparts stores like Pepboys.

I know some people don't think they work, but my personal impression is that they work great. There have been some battery changes that might possibly have made battery problems get less frequent but I'm pretty sure I bougth the washers when I didn't change my battery and there was a big improvement with the same battery. Put the red on positive and the green on negative. I use the same washers for years. It *is* a little hard to believe they don't wear out, use up their chemicals, but who knows. All I know is I don't have gunk problems anymore, and only use baking soda once every year or two or three.

The liquid in the battery is sulfuric acid with a little lead dissolved in it. The gunk is some sort of sulfate, with maybe, I don't know for sure, some lead sulfate. That's why it's yellow, from the sulfur.

No. It does mean some acid got out, but that's not the same thing.

No. There's loads of acid still left inside. It doesnt' take much acid to make that crud.

No. It's not like a flashlight battery's leaking.

About 20 or 30 years ago they came out with No-maintenance batteries, which couldn't be opened to add water, and which also I think meant that the acid coudn't get out. I lost track of whether these things were as good as they said. Ialso lost track of whether there was some small vent for each of the 6 cells in a 12 volt battery. I think there was. I think they used a slightly different acid or plate chemistry.

A couple years after that, they came out with Lo-maintenance batteries, that looked like No-maintenance, in that there seemed to be no caps for the cells, that the battery coudln't be opened to add water. But they had just redesigned the caps, put 3 caps together (and used two of them, for a total of 6 caps) with a very low profile and no apparent place to lift, so they looked like No-maintence, and I think the chemistry was slightly different so it was not necessary to add distilled water as often as it used to be. And maybe voltage regulation of the charging system had gotten better, because charging with too high a voltage causes water to evaporate from the electroyte, which is water and acid. Anyhow, it's true, I think, that one doesn't have to add water to batteries nearly as often as one used to. I'm not the best example of maintenance, but I only check the battery ever couple years. I never needs much water, if any.

Be sure to tighten the terminals tight enough, but not too tight!! :)

I haven't looked for stainless steel bolts, and I did once in 45 years have the bolt rust through, largely because of the battery acid, but they sell replacement terminal bolts, and it was easy to replace it.

But once or more I havent' tightened the bolt enough. When it is at all loose, that makes it more likely the crud on the outside will get up between the post and the terminal. When it's properly tight, it either doesn't or it takes longer, not positive. So one time, I'm driving and the car stalled and I was taking a friend to catch a train so I didn't want to waste time. I touched both terminals and one was hot. That's because it was loose. I just turned it left and right as much as it went and then tightened the bolt and the car was fine after that. It wasn't actually that loose, and there was none of the visible crud, but maybe there was something else.

[mm]

So why can't we do that now?

[Tegger]

blueman wrote in news: [e-mail]:

Sure is. It will keep building up until it literally severs the battery cables and destroys the hold-down clamp..

Replace the battery, quickly.

That corrosion happens because the battery-to-post seal is broken, either through age or (far more common) mishandling. You can clean it off and even install those neutralizing-felt washers, but it /will/ come back again.

Clean off the existing corrosion on the cables using a thick paste of baking soda and water. Do this before installing the new battery. And when you tighten the cables onto the new battery, be GENTLE. The terminals only need to be tight enough that you can't rotate them by hand AND NO MORE. Counter your tightening force with opposite force applied to the other side from the tightening nut.

[aemeijers]

Take a flashlight and look down alongside the battery, and see if the tray is painted metal or plastic covered. If painted metal, and you see rust when you peek down there, good idea to pull the battery and repair as needed. (paint, reinforcement, etc.) It can ruin your whole day if you are driving down a bumpy road, and the rusty hold-down bolt breaks, and the battery bounces and shorts out against the inside of the hood. BTDT.

Yes, I grew up driving junk. (Why do you ask?) But on a young car, cleaning in place is usually fine.

[Stormin Mormon]

The car batteries I've used were acid. It's very possible that Coca cola helps clean the terminals, though.

[Stormin Mormon]

I've done that. Big spark.

[mm]

Maybe the battery is good but the charging voltage is low. Have you measured it. Should be about 14.5 iirc. If too low, it won't put enough into the battery, even a good one.

Maybe the charging voltage is low because the fan belt is loose that powers the alternator. Or maybe their is tension thing for a serpentine belt and the spring is getting weak.

How do these ideas sound to you guys? Because I'm having the same problem described above, and I have to try to fix it soon.

[mm]

And sometimes the car won't run as well for a while after disconnecting the battery. For me, that's about 5 seconds, but the manual makes it sound like it could take an hour to get back to normal.

[aemeijers]

Stop by pretty much any local auto parts store, and take advantage of their free charging system check. Try to go when it is slow, not on Saturday morning when the lot is packed solid, so the tech is willing to spend more than five minutes on it.

[mm]

A good idea, but it will be difficult for me to do that when I'm going to fix it myself. I'll feel like I'm taking unfair advantage of them, even if they say there's no commitment.

[hrhofmann]

It is definitely not alkaline!!!!!

[blueman]

Wow - that sounds quite unlucky - so just out of curiousity what were the symptoms and results you observed from the broken-free battery and short?

[Nonny]

"Stormin Mormon" wrote in message news:ho8uin$9mg$ [e-mail]...

Back in the "olden days," all we'd do was an occasional washing of the terminals with baking soda and water. Occasionally, and especially with a new battery, a liberal application of Vasoline mixed with baking soda would keep the terminals in like-new condition. My next door neighbor had a Vasoline/baking soda bottle that he claimed dated from his return from WW2, that he kept in the garage and used occasionally on his auto battery terminals.