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Quick Question about Negative Battery Cable. . .

Old Mar 19, 2007 | 02:26 AM
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Default Quick Question about Negative Battery Cable. . .

Is it mandatory to disconnect the negative battery cable before removing the alternator? The reason why I ask is because the battery on mine is underneath the back seat. :?
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Old Mar 19, 2007 | 05:40 AM
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I would be inclined to lift the battery positive at the battery. That way you're removing battery potential to ground at the alternator terminal while working the alternator. Lifting the battery negative doesn't really help you. Does that make sense?
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Old Mar 19, 2007 | 06:00 AM
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Originally Posted by markwb
Lifting the battery negative doesn't really help you. Does that make sense?
I suppose so. . . it'* just that AllData said to unhook the negative side for some strange reason. :?
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Old Mar 19, 2007 | 07:03 AM
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Yes, the negative is always the cable to be removed before any work is performed. It is not suggested that you work on your car or alternator for this matter w/o unhooking the battery. The most it does is cause you to learn how to set the clock. (I'm VERY good at setting my clock... )

Look at it this way Mac.. if you take a moment and unhook the battery, you won't be able to test if your fillings light up when that tingly feeling of electricity passing through your body occurs.

Be safe..unhook.
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Old Mar 19, 2007 | 07:42 AM
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Unhook both. The charge lead at the alternator is hot off the positive terminal from the battery.
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Old Mar 19, 2007 | 08:03 AM
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And it only takes like 30 seconds to lift up the seat to get to the battery.
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Old Mar 19, 2007 | 08:10 AM
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Originally Posted by willwren
Unhook both. The charge lead at the alternator is hot off the positive terminal from the battery.
but if you disconnect the negative; that hot lead isnt so hot under the hood, the nearest discharge location is under the seat

and for the record, it takes about 4 seconds to remove the back seat, and 10 seconds to put it back in.
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Old Mar 19, 2007 | 08:49 PM
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Well.....which ever way you want to do it. Positive , Negative or both. The bottom line is that you are placing the battery on open ckt. Sometimes the books aren't always gospel. In this particular scenario there are two different (maybe 3) schools of thought, neither of which are wrong.
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Old Mar 19, 2007 | 11:03 PM
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Thanks for all the help fellas, I'll go ahead and unhook both cables.
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Old Mar 19, 2007 | 11:23 PM
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I once didn't unhook the negative when pulling my alternator. The power lead hit the body of the alt, which rubbed the accessory bracket as I lifted it, sparks flew, ring terminal arc welded to the body of the alt, insulation on power lead was cooked and smoking.

So I ALWAYS unhook the negative.
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