car battery cable whiteish corrosion

Lead II sulfate.

Baking soda (sodium bicarbonate).

It's some salt of sulfuric acid, I think.

Almost like Dean, I just use baking powder. (I usually don't have baking soda.) I don't bother with the instructions I saw 50 years ago, to iirc mix with water and brush it on. I just pour some on straight from the box, then slowly pour on some water, slowly enough so that I don't wash away the powder before it does its work. When it stops bubbling, you're done.

The box of baking powder you can then put in the refrigerator to absorb smells. I think I went 25 years, maybe 40, on one box.

YOu should definitely get a set of felt washers that go under battery clamps, one red for the positive terminal and one green for the negative. They are soaked in some pair of chemicals that prevents the white stuff in the first place. IIRC, they suggest replacing them every year or 3, but I've used the same set for 20 years on successive cars and I barely get any white stuff. When you start getting more than the usual amount of white stuff, replace the washers. They only cost a couple dollars. Here's what I mean but they are a lot cheaper if you buy them at a local autoparts store. I think it has to do with shipping costs, that's why they are pushing buying 10 sets. If you bought 10 sets, it would be enough for you and your family for 50 years.

What chemical is that?

an anti-oxidant, like the NOX paper piston rings come in. After cleaning everything well.

Baking soda or something like this

either add your felt washers or not but cover the terminals/clamps hardware with a sealer: (Permatex turned up first on a web search; there are many brands)

AMuzi snipped-for-privacy@yellowjersey.org wrote

These all suggest baking soda or coke to clean battery terminals

I wonder why both work given one is acidic and the other basic?

I was curious what the magical solution on the felt was but I only found so far the grease you're supposed to use on terminals after tightening when I googled.

petrolium jelly (aka vaseline).

grease is silicone based (and a thickener). Interestingly it says that it's an insulator.

Lithium Grease Apply the grease AFTER you've tightened the bolts. The purpose of felt washers is to prevent shorts (not prevent corrosion).

only conductive grease is graphite grease All others are NOT conductive, including dialectric grease. Silicone-based, White Lithium grease, Copper grease, Teflon based, Oil-Based & Wax-based greases are all non conductive.

Dialectric grease is a non conductive silicon based grease.

Petroleum Jelly, Lithium Grease & Dialectric grease are all ok.

one says to use wheel bearing grease on the terminals.

On Feb 03, 2022, Gronk wrote (in article<news:sth4ik$116p3$ snipped-for-privacy@news.mixmin.net>):

Depends on the color.

Greenish-bluish deposits are probably copper sulfate. Cu (s) + 2 H2SO4 ==> CuSO4 (aq) + 2 H2O + SO2 (g) The copper in the terminal clamp reacts with the battery terminal lead.

If it's more white than green and you have aluminum clamps, then it's most likely aluminum sulfate for the same reason as for the copper sulfate.

Whitish powdery corrosion is probably lead sulfate. Pb (s) + H2SO4 (aq) ==> PbSO4 (aq) + H2 (g)

This reference says it forms on the negative terminal more often but I generally see it more often on the positive terminal but I don't know why.

Ron, the humblest guy in town.

Those felt washers are for a different purpose than for corrosion.

For corrosion protection, almost any grease on your shelf will work, some better than others under various cold/hot temperature conditions.

Even K-Y Jelly will work but put the grease on AFTER you tighten the connections because all but the graphite greases are non conductors.

Sometimes it's a yellow crust from sulfating salt used on wintry roads.

Not everyone agrees with that (and you don't say what that other purpose would be).

Prevent corrosion around battery terminals and prolong battery life The pads will not stop the battery from leaking. They can help prevent corrosion on the terminals. I just use Vaseline.

Elswehere someone says "The felt washers when saturated with heavy oil will wick oil onto the post and clamps to keep off the acid and oxygen that cause the corrosion." but he doesn't say they come saturated with oil, and they don't. They are dry or practically dry. All these ideas with oil and vaseline are messy, imo, compared to the commercially-sold washers.

I ridiculed buying 10 pair, but here 10 pair are only %9. One for him and one for her, two for the kids, and they can give the other 6 pair as Christmas gifts to people they don't really like.

The magic ingredient is oily wax. The wax would block the acid/liquid on top of the battery from reaching the clamps.

Per two mfg's MSDS:

1. COMPOSITION/INFORMATION ON INGREDIENTS Name Wt. % Lube oil, 500 SUS 70 Inhibited paraffinic oil 30 Additives are primarily fatty acid and fatty acid esters.

% by weight CAS Number INGREDIENT PEL PPM TLV PPM TLV MG/M3 UEL

88 64742-01-4 Residual Oils None None 5.0 N/A 12 Non-hazardous Additional elements may be evident in trace amounts of less than .01%

It's lead sulfate, and a baking soda wash (as recommended in the manual that comes with the Ford Model A) will remve it. Then spray with battery terminal protectant so it doesn't form again.

You might also consider adding powerpole connectors so you can disconnect the battery with the disconnect point being far from the terminals. More convenient if you do it often.

--scott

Neat, thanks, I always wondered what those felt things were for. Seems that older batteries build up this salt/lead corrosion a lot faster.

Ah, that won't do for me, I have 11 cars ;)

Then again, at best half of them have a battery.

If I had a bigger yard, and access from it to the street, I'd probably collect old cars like I collect old vcr's, old 12" crt tvs, and old PCs.

I miss having a bigger yard, but I'm probably better off without all those cars.

When I took auto maintenance in the seventies, the teacher told us (as I recall) the felt washers act as a barrier which is why they're dry.

He would keep a swatch of felt in the shop for when we worked on the teachers' cars (which is how we learned how to do basic maintenance).

I could be wrong though, as they may serve some other unknown purpose. We should probably search for references to figure what they do for sure.

I googled quickly but I don't know what thickness or "grade" felt to get.

Do you?

On Thursday, February 3, 2022 at 8:35:58 PM, Paul in Houston TX wrote:

I looked it up and "found the answer on the Internet" so all must be true. :)

This one explains the felt washers can become an acid sponge over time.

This says the felt is mechanical in that it "blocks" fumes from metal. "The washers will only protect the bottom of the post and the clamp. The spray will cover the sides and top. Any unprotected part of the clamp is subject to corrosion."

This says the felt pads prevent electrical shorts across the two terminals

"These washers help prevent high-resistance shorts across the battery case (when batteries get really dirty"

This says the felt pads are "doused with a special chemical", but whenever people don't say the chemical name it usually means they don't know what they're talking about.

This makes a good point that un-oiled felt washers would get wet & stay wet. Here is the question we're asking about do the felt pads work, and how. Product specs just say the pads are "saturated with oil" (but what oil?). These washers say they are saturated with a grease which doesn't evaporate. This oil/grease was "invented in 1914" and it's what they're saturated with. This says the felt is soaked with a "special chemical" which makes me suspicious because more often than not a "special chemical" isn't all that special. This one says something interesting about felt on side post batteries. "On a side post battery, the post is actually BELOW the acid level, so a felt washer, even though it could be used, is not going to provide the level of protection as it does on a top post battery. This is where buying terminal grease will help protect."

This says the corrosion is due to metal on metal and not due to acid at all

This explains why the positive post gets more corrosion than the negative "The positive post of the battery has a positive charge, ie there are no 'free' electrons there (they're at the negative post), so this accelerates the corrosion of the lead that makes up the terminal itself, as the lead atoms give up electrons and oxidize, leading to the corrosion that you are seeing. I know that I haven't worded this very well, but I've cleaned countless battery posts and terminals, and I have noticed that on most batteries, the positive post tends to have more corrosion on it, and it is harder to remove than the corrosion on the negative terminal."

This says the way the soda works is the fizz disturbs the deposits.

Lots of corrosion here on the second battery.

I have a small city lot, and my entire back yard consists of 9 cars... one is on-street parked at another property, and another is wedged into a small storage unit. There isn't really room for anything else in my back yard now. Would you like to buy a few cars? LOL

Latest edition: 1965 Galaxie:

Will I get a discount if I buy 3?

I'll need to keep them at your house. No room here.

It's possible that I just assumed they had some chemical poured on them, that then dried, and they enocourage t he idea t hat there are two chemicals because thy're different colors. If it was plain felt, they wouldn't need different colors, but it's the kind of marketing a lot of places do and they never say there are chemicals involved.

Still, I've found most manufacturers do go to some trouble to make a good product, and even if they only made a solution of baking soda, soaked them in that and dried them, i wold think that woudl be better than plain felt. Next time I get a new pair, I will taste them, see if I can tell what might be on them, and if there are 2 different things .