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Discussion Starter #1
I had a suspicion that my alternator was the cause of my electrical woes so I took it to the local parts store and had it checked. It put out a steady 20 VOLTS!!! Good thing I had a lifetime warranty on the alternator. Maybe its a good thing I am redoing my dash and adding a voltmeter.

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1965 406 6speed
1998 Tahoe LT 4x4
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David,

Be careful to assume the "test" indicates a problem. This might be quite okay. Most parts places put the alternator on a machine that causes them to go "full field" and maximum output should be achieved. Most alternators (I'm talking about the factory ones here) are not uncommon to reach 16,17+ volts during full field testing.

Now, if they did other tests and it was "stuck" at 20, yeah there's a problem, you really needed to know what it was doing in the vehicle; Idle @ 1000 rpm's, voltmeter at the (+) and (-) of the battery, should have at least 13.8 volts and no more than 14.8 volts for a factory charging system. Turn on accessories and headlights while maintaining at least 1000 rpms or more. Voltage should not fall below 13.8 ideally. Also revving the engine in this or any other condition regardless of load should NOT result in voltages higher than 14.8. 15+ is a battery frier.
 

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Discussion Starter #3
The test the guy did was he hooked it up to a contraption that ran a belt and spun the alternator. He had an adapter to plug into the unit and connected it to the machine. I had the guy test the new unit at the store and it showed about 14V on their machine doing the same test that the old one showed 20. I hope it is fine for the time being I wont have a voltmeter unit I get off my but and finish the dash
 
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