Positive Cable Turning Black [Archive] - Chevelle Tech

: Positive Cable Turning Black

Aug 9th, 05, 6:27 PM
Well I replaced the the + battery cable on my 67 SS. I am running an alternator with ext volt regulator, one of the Wells volt regulator. Instantly cleared up some hot start problems I was seeing with the old, worn cable. Now, I may drive the car 1 week-end, and then it will sit a couple of weeks before I drive it again, if that matters. Anyway, the cable post is starting to turn black ... What is this a sign of ? Overcharging ??? A cheap cable ? This cable is a Pep Boys variety. Also, I do have A/C , and a stereo with amp. My alternator is a 63 amp size ... Do I need to step up the alternator? Can I go higher amps without going to an internal regulated type? Any and all comments and suggestions would be appreciated... Thanks ... Steven

Aug 9th, 05, 6:51 PM
Sounds like a chemical reaction. Almost like something is on the new battery cable post reacting with the battery. You could try cleaning it but by now it's probably stained.

Aug 9th, 05, 6:53 PM
Lead will turn dark over time. Is this happening so quickly to cause a problem? Don't know. If it gets really dark there may be some other root cause (like vapors escaping from the battery). Try a thin film of whit lithium grease to prevent it.

Aug 9th, 05, 7:09 PM
I'm assuming that the insulation is not black. If the insulation is black, too, then you've got overcurrent: you need less load or thicker guage cable. Otherwise, it is a sign of electrolysis. Your posts are meant to be sacrificial so that your car's electrical cabling doesn't just crumble to pieces. They make pads that go around the posts to slow this process, but don't know how well they work.