Under the Hood: Stop corrosion on battery post
Question: Could you explain why my 2011 Lincoln MKZ battery post develops green corrosion on the positive post? The mechanic at the dealership and the service manager said that some batteries do that and it is normal. The manager said the vents on the wet batteries cause the post to gather this acid and corrode. He suggested a couple of deterrents, such as a copper penny between the posts, spray-painting the post or putting grease on the post to shield it from corrosion. Do you have a solution or idea?
Answer: I believe your battery has a poorly functioning seal between the battery post and case that is allowing vapors or acid to sneak up into the terminal connection. This is more of a nuisance than a problem. I've had fairly good luck using the red and green felt terminal protectors, placing them beneath a just-cleaned terminal. Coating the post and terminal with some “Brush-on NCP-2 Battery Corrosion Preventative” is another method that can bring relief.
If your battery terminals have crud growing atop them, there's a good chance corrosion is working into the more critical, less visible clamp/post connection. Corroded or loose battery terminals can cause difficult or no-starting, charging system issues, and some really weird symptoms to occur with on-board electronics. The good news is vehicle damage is unlikely. It's the symptoms that can be unpleasant.
Cleaning terminals is a fairly easy process. A check of the owner's manual for precautions involving battery disconnection/replacement is a good first step. Yours indicates the transmission will need to undergo a learning period after reconnection to restore shift strategies and may shift a bit firmly or softly until things sweeten. An inexpensive battery “memory saver” can be plugged into the lighter socket.
Eye protection is a must. The black negative terminal should be removed first and installed last, and don't allow the terminals to touch each other or any other parts! Never disconnect a battery cable with the engine running or key on.
Avoid twisting the terminals excessively. Loosen the nut further and gently spread the clamp apart with a large screwdriver. Mix up a container with 2 cups of water and 2 to 3 tablespoons of baking soda. Immerse the removed cable clamps for a minute or so, one at a time, and pour a small amount of fluid/paste over the vacated battery posts. Clean and pat all parts dry with a dampened rag, then use the terminal cleaning brush to bring up some shiny connecting surfaces. Finish up with your preventive products and securely snug the clamps. Wash your hands right away!
Brad Bergholdt is an automotive technology instructor at Evergreen Valley College in San Jose, Calif.
Show commenting policy
TribLive commenting policy
You are solely responsible for your comments and by using TribLive.com you agree to our Terms of Service.
We moderate comments. Our goal is to provide substantive commentary for a general readership. By screening submissions, we provide a space where readers can share intelligent and informed commentary that enhances the quality of our news and information.
While most comments will be posted if they are on-topic and not abusive, moderating decisions are subjective. We will make them as carefully and consistently as we can. Because of the volume of reader comments, we cannot review individual moderation decisions with readers.
We value thoughtful comments representing a range of views that make their point quickly and politely. We make an effort to protect discussions from repeated comments either by the same reader or different readers.
We follow the same standards for taste as the daily newspaper. A few things we won't tolerate: personal attacks, obscenity, vulgarity, profanity (including expletives and letters followed by dashes), commercial promotion, impersonations, incoherence, proselytizing and SHOUTING. Don't include URLs to Web sites.
We do not edit comments. They are either approved or deleted. We reserve the right to edit a comment that is quoted or excerpted in an article. In this case, we may fix spelling and punctuation.
We welcome strong opinions and criticism of our work, but we don't want comments to become bogged down with discussions of our policies and we will moderate accordingly.
We appreciate it when readers and people quoted in articles or blog posts point out errors of fact or emphasis and will investigate all assertions. But these suggestions should be sent via e-mail. To avoid distracting other readers, we won't publish comments that suggest a correction. Instead, corrections will be made in a blog post or in an article.
- No more room on iPad? You’ll need to trim some of that fat
- Decoding mutual funds jargon
- Plus-size fashion bloggers recruited
- Taxpayer clinics fill IRS void
- As banking goes mobile, branch closures rip through local economy
- Employers prepare for demographic shift
- 8th-grader gets venture capital for inexpensive Braille-printer
- Kennametal plans plant closings, job cuts in fallout from oil and gas decline
- Cheap gas lets small business dream big
- Trib 30 stocks drop to 4-month low
- Super Bowl draws big increase in first-time advertisers