electric problem

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Oct 30, 2010 | 07:18 AM

mtwilsonboy

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From: Hershey PA.

electric problem

Lately on my 1982 corvette when driving and I first noticed it at night, I noticed my headlights getting dim and bright and my amp meter would jump with the dimming and brightness. I noticed when driving with my lights off the amp gauge jumps back and forth also. I had autozone test my alternator and they said it was charging between 14 1/2 to 17 1/2 volts jumping back and forth. Do I need a new alterntor or is something else going on here? Thanks for any help you can give.

mtwilsonboy,

Oct 30, 2010 | 10:52 AM

0Willcox Corvette

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Quote:

Originally Posted by mtwilsonboy

The Alternator should not jump from 14.5 to 17.5 volts if the battery is fully charged. If I had to guess, I'd say the voltage regulator in the alternator is bad.

Oct 31, 2010 | 11:06 AM

71corvette

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From: Phoenix Arizona

There is a short to ground somewhere in the car. This could be from a battery wire that has melted near the exhaust manifold like near the starter. Do not rule out the possibility that the battery itself has an internal short. This same exact situation happened to me after I installed a brand new battery. After about a week I was driving one night and the headlights went dim and then bright. The amp gauge fluctuated back and forth. Swap the battery if you and see what happens. If that doesn't fix it, then a main feed wire or circuit has to be touching a ground intermittenly.

Oct 31, 2010 | 12:10 PM

SIXFOOTER

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From: Boca Raton Florida

I doubt the short to ground thing, a short to ground will burn a wire or blow a fuse. If everything else appears to be working but your getting a fluxuating volt meter and headlights I would look first to the battery connections as basic checks, then go to the regulator. Your most like culprit is the reculator as Wilcox pointed out. In your autozone test it was "Jumping", it should never jump unless something that draws a heavy current is being switched on and off, like headlights. Sometimes when idling you can see the volt meter or amp meter move a bit with the turn signals on, bit nothing like the 3 volts in your test

Oct 31, 2010 | 12:24 PM

gdh

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From: Canada

Had this happen just before the alt. finally went.

Oct 31, 2010 | 01:01 PM

noonie

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From: Florida

Bad regulator.
Maximum output on your alternator can be anywhere from 13.2 volts to 14 .9 volts depending on what regulator is in it. Most are 14.7 volts.

You can get a reman 85 amp for as little as 75 bucks or a 63 amp for around 40 bucks and up.

Nov 1, 2010 | 11:02 AM

stellar

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From: Pgh. Pa.

Probably a bad alt, but could also be a bad battery.

Nov 5, 2010 | 12:27 AM