Dear Tom and Ray: I own a 1992 Honda Accord. About six months ago, I couldn’t get the car to start. Looking under the hood, I discovered that the clamp on the positive battery cable had completely corroded away. I made a quick fix with a hose clamp, but figuring that was only a temporary solution, I took the car to my local dealer and had the battery-cable harness replaced.
Yesterday, I went to give someone a jump-start and discovered that the new battery-
cable clamp on the positive side had turned to mush. It is literally liquefied, and appears to be melting away. It was also completely covered with a mound of bright blue-green, powdery material. What’s going on?
– Joel
Tom: The blue-green powder you’re seeing is the corrosion that results when the acid in the battery meets the lead and copper of the connector. The mystery here is why the battery is releasing gas. Modern batteries are sealed, so they’re not supposed to out-gas at all. But they do have vents so that if the pressure inside gets too high, they release gas instead of exploding.
Ray: One possibility is that your battery has a bad cell.
Tom: But a more likely explanation is that your battery is getting overcharged by the alternator.
Ray: I’m betting that when you went to the dealer, you just told him what to replace – you didn’t let him diagnose the problem.
Tom: If you had, instead, just gone in, shrugged your shoulders and pointed at the melted terminal, he probably would have done a real diagnosis and tested your charging system. That’s what he needs to do now.
…
Dear Tom and Ray: A few weeks ago on your radio show, you got a call from a woman who asked you guys to settle a two-part dispute with her husband. Her husband objected to her heavy key chain, and she was told that her husband was right: Heavy key chains can indeed cause damage to the key-shaft thingy. However, I distinctly remember that back in 2002, you had a similar call from a woman who was borrowing her father’s car, and it was being lent to her only on the condition that she remove other keys from her key ring so that no extra weight hung off the ignition key. You told HER that the extra weight from other keys was so negligible that it would not cause any damage. So, which is it?
– Michelle
Ray: If you have seven or eight keys on your key ring, you’re not going to do any damage. The ignition switch can handle that.
Tom: But if you carry around 20 keys, that’s a fair amount of weight. That constant downward tug on the ignition switch can cause it to wear out prematurely.
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