Help! what should the alternator voltage be?

mootang

New Member
Dec 5, 2004
907
0
0
texas
what should the alternator voltage be? I just replaced my battery and I checked the voltage while running and it was 14.6 Is that overcharging or is that about right. I want to make sure I don't kill my new battery.

thanks,
scott
 
Scott, I agree that this sounds fine. If you were to creep up toward the 15 volt number that Roland mentioned, that's when I would start to worry.

I would expect you might be seeing this voltage after the initial start-up when the car is cold. Once it warms up a bit and recharges itself [from sitting overnight, the starter's draw, etc] it should settle down to ~14.4 volts max.
 
Now remember this is regulated voltage. If you ever thought your alt was really under or over charging, you can ground out the "marked" mounting screw on the voltage regulator. This will take the reg out of the picture and the battery voltage will (should) jump up to 16-18 volts. This allows you to isolate each part and maybe just replace a bad reg instead of a alt.