How to Wire an AC Delco 3 Wire Alternator

by K.K. Lowell

The AC Delco 3 wire alternator was used in most General Motors products, and many types of heavy equipment, for a long time, which makes it readily available. This alternator has the advantages of high output, compact design and ease of use. With the proper brackets this alternator can be adapted to any vehicle or engine-powered equipment. Wiring this alternator is well within the capabilities of anyone with average mechanical skills.

Step 1

Disconnect the battery negative terminal.

Step 2

Connect a length of 10 gauge wire to the output stud on the back of the alternator using a solderless ring connector. Connect the opposite end of this wire to the starter solenoid. Simply connect to the same terminal as the positive battery cable.

Step 3

Plug the alternator connector in the receptacle on the alternator. Splice a 14 gauge wire to the smaller pigtail from the connector. This wire runs to the IGN terminal of the ignition switch. Connect a small 12 volt warning light in series in this wire.

Step 4

Splice a 10 gauge wire to the larger wire on the alternator plug. Use a solderless butt connector to make the splice. Make the wire long enough to connect to the same terminal on the starter solenoid as the battery positive cable and the alternator output wire. Connect the wire to the terminal with a solderless ring connector.