Negative Terminal Clamp Corrosion

[Citroënbender]

This notably occurs when a battery is undercharging - typically from a bad alternator.

What I’m wondering about is why it seems to be ongoing after the situation is resolved? Is the terminal clamp so chemically imbalanced that it forever remains in a state prejudiced towards oxidisation?

It’s a Franco type question, is he un-banned yet?

[Vesper Martini]

Its is a Franco question, What did Franco do this time?

[aussiblue]

The answer is here: https://batteryuniversity.com/learn/...internal_short

...This reaction cannot be avoided because the electrodes in a lead acid environment are always reactive. Lead shedding is a natural phenomenon that can be reduced but not eliminated.

[Citroënbender]

That’s not quite the same AB, terminals are good and battery itself charges/discharges normally.

It’s the clamping part of the car harness’s negative lead which suffers this “runaway” effect where even removal and washing in an alkaline solution doesn’t seem to arrest the decay.

[Blue Dog]

I'd hazard a guess & say it would be caused by the two dissimilar metals being the lead battery post & the battery terminal, which obviously isn't lead, being in contact with an electrolyte, (even water can be a weak electrolyte).
There's probably some form of leakage of gas, or even the battery acid, between the seal of the battery casing & the battery post.

[TICKFORD220]

My bf xr6 does exactly the same thing,battery and alt are perfectly fine,once it starts getting that fuzz youll never get rid of it without replacing the battery and battery terminal/earth lead.
Ive removed the battery terminal and fully cleaned it(removed the fuzz back to clean metal) and then used bi carb and boiling water to neutralise the acid on the terminal and battery posts,it only comes back with avengance.
I just regularly clean mine.
I have replaced the battery on my bf,made no difference,because i havent replaced the earth lead,its had that fuzz on it so it will always come back......
Had exactly the same issue on my eb ghia v8 as well,until i got new terminals and a new battery,never happened again,it was that bad that it ate the complete terminal away to almost nothing and it snapped off pretty much.
Much easier on the eb,the terminals can be replaced,bf needs a whole new earth lead.

[Fed]

I use Vaso.

[LG17]

Originally Posted by Fed

I use Vaso.

I started using that about 60 years ago and never stopped.
I rarely have any kind of problem.
I was starting to think that no-one else still used it.
I actually buy petroleum jelly in a 5kg tub as it has many, many uses around the place.

[jaydee]

Originally Posted by Fed

I use Vaso.

Tell us more, no wait, dont.

[aussiblue]

that’s not quite the same AB, terminals are good and battery itself charges/discharges normally.

From that link (https://batteryuniversity.com/learn/...ternal_short):

"The terminals of a battery can also corrode. This is often visible with the formation of white powder as a result of oxidation between two different metals connecting the poles. Terminal corrosion can eventually lead to an open electrical connection. Changing the connecting terminals to lead, the same material as the battery pole of a starter battery, will solve most corrosion problems."

[aussiblue]

I started using that about 60 years ago and never stopped.
I rarely have any kind of problem.
I was starting to think that no-one else still used it.
I actually buy petroleum jelly in a 5kg tub as it has many, many uses around the place.

I hear Kiwis prefer natural lanolin.

[LG17]

Originally Posted by aussiblue

I hear Kiwis prefer natural lanolin.

Of course they would

[.:4:.]

I havent had the green occur on my bfs battery, and ive had that car a long time. It used to happen every while on my first car. Before i changed the terminals, id just wire brush them and they'd be sweet for months. On that car due to big cables for amps, i put on gold plated terminals from jaycar, and they stopped the green mess. Plus, being 17 at the time, having a chrome pipe to a pod filter, proper warm air intake, the gold battery terminals. Yep, pop the bonnet, and ****er spec. I just couldnt at the time justify at the time for the gold plated positive terminal with the built in voltage screen.

[Citroënbender]

One of the terminals that dissolved terribly, did include a lead “cap” or sleeve in direct contact with the battery post. It still dissolved.

A common link between the two failures I’ve experienced, other than alternator breakdown, is that both terminals were pressed metal types. Have a few cars with ancient brass terminal clamps, a bit tarnished but still otherwise good.

The forged brass terminal clamps from Projecta, look like they’ll do nicely. I bought a battery cable lug crimper some years back and it lives in my occasional workshop. Worst case I’ll use that to put ends on a cut length of fresh cable.

[Franco Cozzo]

Originally Posted by Citroënbender

This notably occurs when a battery is undercharging - typically from a bad alternator.

What I’m wondering about is why it seems to be ongoing after the situation is resolved? Is the terminal clamp so chemically imbalanced that it forever remains in a state prejudiced towards oxidisation?

It’s a Franco type question, is he un-banned yet?

I'm back from the dead - I ran off, got accepted into the circus as the bearded lady but got kicked out by Michelle from HR because apparently having manboobs, a pedo mustache and wearing a pink dress didn't cut it, so I did a bit of sales repping for Nick Scali, but the product was average, sank some **** with Ken Bruce but he went mad, so I've come back home.

Usually that build up around terminals is from a damaged and leaking battery terminal.

Usually just boiling water that crapola off and get out the battery post cleaner contraption, imagine Satan's fleshlight.

I'm hesitant to use battery terminal coatings just in case they end up creating high resistance joins.

I see you have a DIN battery, real men use VT-VZ Commodore battery terminals, just ask Michelle from circus HR:

https://tridon.com.au/products/Matso...34719/MA100BL2

[Citroënbender]

Good to see your Dad un-banned you. He even might have to come along when we all go for post-lockdown borscht, piroshkiy and too many drinks.

I used these terminals, the negative version:

https://www.projecta.com.au/battery-...ged-brass-bolt

Had to spread it slightly, and then drill oversize one side of the fastening holes to allow realigning of the pinch bolt.

[aussiblue]

I used these terminals, the negative version:

https://www.projecta.com.au/battery-...ged-brass-bolt

I prefer these:

https://www.projecta.com.au/battery-...ion%20Terminal

[Franco Cozzo]

Originally Posted by aussiblue

I prefer these:

https://www.projecta.com.au/battery-...ion%20Terminal

image

Where have they been all my life? Would have made so many things much easier

[Citroënbender]

Have you seen the similar one with triple fusing, also from Projecta?

Edit: AB is beating me again!

[aussiblue]

Where have they been all my life? Would have made so many things much easier

Supercheap used to sell them.

These which also have fuses, can also be very useful: https://www.projecta.com.au/battery-...ution-terminal

[Franco Cozzo]

This joint has some good stuff too:

https://www.swe-check.com.au/product...tribution-unit

[Citroënbender]

That clamp you linked is very similar to OEM fitment on the 147GTA Alfa.

Also the first aftermarket one I’ve seen that locked into the indexing holes atop a DIN battery.