Battery corrosion question...

[Smokee]

A few weeks ago while out for a cruise, suddenly my battery went dead on me, and I mean right now dead too! Luckily I got into an am/pm station under one of their overhead lights. Popped the hood and looked at the battery.

It was covered in a fine semi sticky ooze and smelled strongly of battery acid. I had just done the oil and filter and a minor tune up (plug wires go next month) and had cleaned the battery and terminals. I put the little red and green anti corrosion rings on the battery too.

Other than that everything looked ok except the positive cable had turned a powdery black color and when I removed it (after pulling the negative cable) It was completely corroded over on the post and inside the cable end. The battery is only two years old, and the alternator in new (6-08) regulator checked out ok.

I cleaned the post on the battery, and on the cable with a battery tool, and hooked it back on the battery with the negative cable. I always keep a battery charger in my car or truck, for emergencies, and the am/pm attendant let me hook it up for a quick charge. Fifteen minutes later, I hit the key and it fired right off.

This is the third time this has happened since I have owned the car. Everything checks out ok, even the battery. Is this a quirk of the Mark VII's, or is something wrong here?:eek:

[Drake_tr7]

Let me give you some good advice. Get a can of NAPA battery terminal protectant. Forget the rings, clean the crap out of the posts and clamps, wet em down with the stuff before you clamp them down. Spray on a few coats when you're done and they'll be like that when you get back :) Unless you disturb it with a charger or jumper cables you'll have zero corrosion from now on...been using it for 30 yrs ;)

[Bluegrass]

This is more complex than most think.
A battery/charge system that shows these signs should be looked at for two items.
1 an overcharging condition.
2 a bad cell that causes an over charging condition.
Over charging can be a bad regulator and or an alternator or battery in any combination.
A bad cell looks to the alternator as a battery that can never be charged up to float value. Example: 6 x 2.17 = 13.02 volts. If one cell is down on voltage or capacity, then 5 cells at 2.17 volts = 10.85 voltsa + one cell at reduced or no voltage does not total the final float voltage and so the battery appears to the regulator as uncharged. This condition causes cells to bleed electrolyte and outgas which causes the corrosion to terminals and cables.
Remember that the regulator has an internal voltage reference the battery must come up to in value. If not, then charging current flows as long as there is a difference.
One or both these conditions damages a good battery and causes needless alternator brush wear and overheating.
The system must be completly tested out for dynamic operation and not depend solely on parts replacement that may leave an ongoing problem until it shows up again later.

[Smokee]

I will give Drake_tr7 remedy a try first, and then I will go over everything again.

I have a Mechanic (ford/mecury/lincoln factory trained 23yrs experience) who put this car thru the ringer the first time this happened right after I bought her, and found nothing wrong. Everything was tits up right on the money (for an almost stock Mk7 lsc se) but he did tell me that something had been done to the car to increase the power and I assumed it had a performance chip put in it.

I hate computers in cars! The computer was built for work or home, not in my vehicle! It was the only place left where big brother couldnt touch me, and now I went and bought a car with one in it (I am told it had more than one computer!) I can fix anything that goes wrong with my computer at home (night courses at Comp U Serve tech) but a computer in a car baffles me to no end. My Mechanic told me to leave well enough alone, and just drive the Mk7 till the wheels fell off, and I said ok, so be it!

So I will just spray the stuff on the battery and see how it works, and go from there. Thanks for the help guys, I appreciate it a lot!

[Drake_tr7]

Don't just treat it like a mechanic in a can Smokee. The posts and clamps have to be CLEAN for it to work. And like I said wet the posts and clamps before you install them.;)
And BG is %100 correct, overcharging will cause the blackening you describe, although in my experience a healthy system will also do it.

[Bluegrass]

OAKEE DOAKEE, I gave you the whole overview so take the easy road and have fun again.
Hint, if you think this car's ECM presents a difficult understanding, wait till you get into the ones' after 1997.
They are called power train control modules (PCM) for short and control not only the motor but the transmission and many other part of the vehichle depending on model and options.
They are already on the next generation of PCM called the CAN system that is a mandated standard by the EPA but is still unique to each mfger as to program, code asignment etc.
There are now already over 1000 P service codes as well as codes unique to the helper modules that have their own programs you can not even access without high end scanners.
Horses and Buggies begin to look good again.:)

[demonswede]

How can corrosion on plastic battery wall and battery holder (if of metal) occur, as these are not directly connected to any of the battery poles or connectors? No doubts that corrosion can occur on the battery poles!!

Is there a leak in the battery - is the battery defective (even if charging)?

Gel batteries seem to be the best here - and are really advantageous for cars with indoor batteries.

[Smokee]

Well then........guess its time to design myself a truly unique Trike, without any computers involved, and head for the wilds of Canada, where I drew my first breath.

Long time ago, while doing a dime up in Walla Walla Washington ( Walla Walla, the town so nice, they had to name it twice!) I read a book called 'Ringo' about a cowboy gunslinger, who had never been out drawn in a gunfight. When his life got to the point that there were no more challenges to face, no more up and coming gunslingers to challenge to a high noon gunfight, he went out into the desert, found an old knarley Methuselah tree to sit under; pulled his .44/.40 out, took all the bullets out except one. Spun the cylinder, put the barrel to his temple and squeezed the trigger. On that day, he turned 41 years old, and on that day under a hot sun and with peace in his heart, he died.

They found his body, what was left of it a few weeks later. He was facing south toward the Rio Grande and some who were there swear that he had a smile on his twisted sun baked face.

Growing up in the late fifty's and early sixty's, I learned how to do things by using my wits and learned habits. I will never be beholden to a box full of wires or circuits, transistors and diodes. I made it this far without them, I think I can do another twenty years or so without them too.

[Huff]

That's Zen and the Mark VII mechanic. Anyhoo, just get a new battery if you're gonna unthink it. New batteries work great in any car. But the mark vii is chock full of technical wonders that require a systematic approach as suggested by the respondants. Fortunately it's not comparable to the ever changing network technologies we are using here. I've seen nice clean terminals in dead batteries and blackened posts in healthy systems. So I can't say if your "rule of thumb" approach to car batteries is better than the analytical approach but if you plan to live with this car, the chickens will come home when you try troubleshooting the air ride and braking system.

http://en.wikipedia.org/wiki/Car_battery

[John Dancy]

...
The system must be completly tested out for dynamic operation and not depend solely on parts replacement that may leave an ongoing problem until it shows up again later.
Once again, you've used one or two sentences to describe what it takes a paragraph for me to explain.

Thank you.

<OS pulls out the scissors and glue>

[John Dancy]

How can corrosion on plastic battery wall and battery holder (if of metal) occur, as these are not directly connected to any of the battery poles or connectors? No doubts that corrosion can occur on the battery poles!!

Is there a leak in the battery - is the battery defective (even if charging)?

Gel batteries seem to be the best here - and are really advantageous for cars with indoor batteries.

Our regular batteries with removable caps give off a gas while being naturally charged by the car. This gas can solidify on just about anything. It shouldn't take less than a year to build up corrosion on the outside of a battery.
I would disconnect both terminals and test the battery.
If that passes, then reconnect it and run the car and test the voltage regulator under real driving conditions with a plug and play voltage tester. I always test the alternators on a machine at AutoPepZone (twice). Lastly, replace the ignition switch on all pree 1990 vehicles.

If I could shrink the font in my signature, I'd add Bluegrass' reply form above.

[gadget73]

Make sure you neutralize the acid after cleaning it, or it will not stay clean for long. A cheap remedy is a simple baking soda and water solution. Pour some on the battery and wait till it stops fizzing. Pour more on and keep doing this until it stops fizzing when you add the solution. Rinse the battery and tray with regular clean water and re-connect everything. .

[Steve Moran]

When that cables start to show any sign of corrosion under the insulation you can almost be assured that the corrosion is working its way up the cable like a worm.
Grasp the cable insulation and give it a squeeze, if it has give or what feels like hard lumps under the coating then it is corroded up inside. The corrosion car be as far back as 6 inches.
Not unlikely for a charging system of that age to have it happening.