CS alternator question.

[BP68]

Should this be in the electrical section?

I have a 89 suburban motor in my truck and I am running the serpetine belt with accys on it. I used a EZ wire wire harness and got a new plug for my CS style alternator that was on the donor suburban.

From everything I found the way to wire my alternator (and the way a gm schematic shows to wire this aternator) is a key on hot wire running to a 194 bulb then to the L terminal at the alt plug. My battery wire runs from alt stud down to starter stud, where battery hot is connected.

When I turn key on, bulb lights, when eng starts light goes out. When checking voltage at alt stud with meter, I was showing 13.0 volts (which is too low) after a quick trip around the block, I was showing (12.5).

Unplug alt and voltage goes to about 11.99 (battery is weak and has not be charged up)

To me this sounds like a faulty regulator in the alt that is only partially charging. With alt plugged in and eng running I get around 12.5 volts at alt stud. With alt unplugged and eng running I get around 11.99.

Sound right to you guys? Any other advice?

Thanks