Hi everyone, I just finished installing a carbed motor in my 88 IROC. I removed all wiring except for the windshield wiper motor, blower motor, and starter wires. I am having problems with the alternator wires. There are 3 of them. A brown one that goes to a guage, a red one that goes to the starter, and a tan one that goes to the ecm. Since I removed the ecm I don't know what to do with that wire. Is my only option a one wire alternator? I heard that I can connect that wire to a 12 volt ignition source and the alternator will work fine that way. Is this true? Thanks for any help!

 

The heavy one with a lug on the back can go to the battery thru a fuse link, or to the starter junction with a link. The plug normally has 2 wires, the heavier of the 2 should tie to the 12 volt system through a key on circuit. The other wire is a sense wire. You should tie it also to a key on 12 volt line, however ideally you should use a 30-50 ohm 5 watt resistor in series with it, or use a diode so that you have some voltage drop on the sense wire. The sense wire determines how hard the alt charges by controlling the internal voltage regulator. You can tie it directly to 12 volts, but by doing that the alt will basically only trickle the battery. The voltage drop to the sense wire lets the alt keep the battery charging at a voltage higher than normal terminal voltage. www.alternatorparts.com has an online manual for Delco units with schematics.

 

Danno, I actually have 4 wires including the one that goes on with a lug. I believe that goes to the battery. On the connector, I have 3 wires. I believe the thick red wire goes to the big starter terminal with a fuse link. Then there is a brown one that goes to the driver's side harness and goes to the guages. The last one is the tan wire. I was told that I can just hook that up to a key 12 volt source. Do you think I would have any charging problems by doing that or do you have any different recomendations? What kind of diode would you hook that wire up to? Thanks for your help.