Alternator question?

[ORFORD2004]

In my alternator i have a stud and a terminal. The stud is the output of the alternator but what is the purpose of the terminal? That terminal give you 12 volts or need 12 volts for the alternator to charge.

Thanks!!!!

john

[spider2081]

not sure what alternator you have but if its the one with a built in voltage regulator the small push on terminal is + 12 volts from the alternator out light. I believe this 12 volts energizes the field circuit in the alternator and is required for the alternator to work.

[ORFORD2004]

That is what i think because now the alternator is not charging.

[spider2081]

From my 1981 wire diagram

That wire has voltage on it in "start and run" position of the ignition switch. It is not a fused wire but it does connect the ignition switch to the hot side of the fuse panel and then passes to the alternator. If the "Battery Warning" light bulb in the tac burns out it will cause the alternator to be in-op. If you know you have no voltage on the wire at the alternator I would check the ignition switch connector next. On the ignition switch the wire is blue/black to the connector. From the connector the wire is blue?red and shares a pin in the ignition switch connector with a blue wire for the parking/headlight light switch. If your lights work the ignition switch itself is probably not the issue. The blue/red connects to fuse 2 to power that fuse and becomes blue/black in that connection. There are 2 more connectors before it reaches the alternator.

[andredarago]

I have elecrtical problem with my spider 1981, when the car is stoped it seems that the alternator is pulling 3amps on my voltmeter if I take a lecture from the alternator to the wire that connects to the starter it gives me a reading of 3amps.
Would the problem be the alternator or a bad connection at the starter.
Thank's
Andre