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Discussion Starter #1
Need to find the fix fast.. Woodward cruise is 2 days away and I am losing road time..
Was cruising tonight and Alt light came on. Bee lined it back home (20 min, 10 miles). I have a new battery, old ld but new looking alt. Repo, concours correct voltage reg. I have heard bad things about the failure rate of these things.
OK where does a electrical illiterate start? I do have a voltmeter and know how to use it. Any help would be great.
 

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Connect your voltmeter to the battery + and -. Start the engine. Observe voltage at 1500 rpm, should be 14.5 to 16 volts. Turn off engine. Unplug voltage regulator. Start engine. Connect a jumper momentarily (do not exceed 10 seconds) between the A+ and F terminals of the VR plug and observe voltmeter. If voltage output exceeds 14.5 volts, replace regulator. If voltage does not increase, or only marginally increases, replace alternator.
 

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Check all wires and belt. If they are good start the car and then disconect the batt. if the car dies alt is bad. If it does not die and everything looks right then you need to have the system tested. Some auto parts stores will do this for free just to make a sale. It is probably the brushes in the alt.
 

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That's a very dangerous test. Automotive batteries produce an explosive hydrocloric gas. The spark from dissconnecting/connecting a battery cable with the engine running is enough to ignite it, explode the battery and ruin your whole week.

Use bartl's test. Much more accurate as to pinpointing the problem and there's no risk of taking a bath in battery acid.
 

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Discussion Starter #7
Swapped out my brand new (500 miles,1 year old) concours voltage regulator and solved the problem. I guess I am going to run an electronic VR instead of the solid state ones that are the correct shape.
Do thay make an electronic VR that is packaged in the correct housing??
 
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