I decided to put a meter on my alternator today. I had an issue where I was not getting any charge, only to discover that the alternator wasn't plugged in. After plugging in the exciter plug, the alternator made loud noises at which point I discovered that the belt was shot. I then replaced the belt to find tat the previous owners had bypassed the smog pump pulley and didn't quite have clearance for the belt. I then removed the pulley, tightened the belt and cranked her up.
The on-dash volt meter jumped from the lower white line to the upper white line. When I just measured the voltage at the battery, I am getting 14.8 - 15V. Do I have voltage regulator problems?

Oh...and just where is that voltage regulator?

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Originally posted by jsloan:
When I just measured the voltage at the battery, I am getting 14.8 - 15V. Do I have voltage regulator problems?

No. That's the high end of normal.

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Oh...and just where is that voltage regulator?

Its a little triangle-shaped thing inside the alternator with two tabs sticking out for the plug.

If you are OK replacing it, I would carry a spare. USA made.

So, this is ok and I shouldn't be alarmed? Is there a reason it would be running at the high end? I'm pretty sure the battery is at full charge. Will this damage any electronics?

Oh, one more thing. If I crank her up and have cabin lights on they kind of pulse. Something is not quite right yet...

That could be the isolator or relay - or a bad diode. Alternator output is actually rectified AC (not flatline DC), and if one leg of the diode bridge is bad, pulsation occurs.

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Originally posted by jsloan:
Oh, one more thing. If I crank her up and have cabin lights on they kind of pulse. Something is not quite right yet...

Do your headlights, dash lights, running lights and tail lights pulse, as well?

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Do your headlights, dash lights, running lights and tail lights pulse, as well?

Yup. I think in the spirit of throwing money at it I will try replacing the VR. I'll be grabbing one from NAPA and swappin it out today.

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Originally posted by jsloan:

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Do your headlights, dash lights, running lights and tail lights pulse, as well?

YUP.

Then the diodes should definitely be checked. Also the diode trio, while you're in there, but my diode trio failures have not caused pulsation.

Check brush wear, too. They can work when short, but sometimes will howl, as they are too short to sit firmly in the rather loose-fitting holder.

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I think in the spirit of throwing money at it I will try replacing the VR. I'll be grabbing one from NAPA and swappin it out today.

NAPA sells two grades. In the spirit of throwing money at it, buy the better one.

http://www.napaonline.com/Mast...on=Voltage+Regulator

I drove around a bit today and the pulsing seemed to quit and the voltage gauge dropped to normal levels. I took it to an alternator shop and had it checked and the guy said he thought it was perfect. So, now I feel better and haven't spent any money to speak of, which is always a good thing. Now, on to the speed-o-meter and the NuTone blender