Ok, getting ready to wire up the car. I have a 3 wire alt, which wires go to what? Does it go like: 1 goes to ground, 1 goes to +12 on batt and the other goes to the gauge?

 

There is no ground connection. The alt is grounded through it's case to the alternator mount.

There is no gauge connection. The volt gauge does not read voltage directly at the alternator.

The heavy wire from the large post on the back of the alternator is the charge wire. It goes to the battery (or starter solenoid).

The red wire coming off the regulator plug is the voltage sense line. The regulator senses voltage through that wire. In most applications, it should go to the same place as the main charge wire.

The color and usage of the third wire depends on the alternator. It is usually brown or white, and it goes either to switched ignition 12V, or to the no charge indicator lamp. It serves to activate the alternator.

If you reply with what specific model alternator you have, I can give you more specific information

 

i bought it about 2 years back, it's a 120AMP alt, I dont remember the brand name. This info really helps me. Thanks.

 

If you can post a pic, I can probably identify it.

 

hey i just switched from Vbelt to serpintine. and my old alt has a 2 wire harness. but this one has 3 what am i to do? lol a little help thanks guys

 

What year and engine is your car?