Join Date: Sep 2000
Location: Shrewsbury, MA, USA
Make sure the F connector on the alternator (closest to the passenger fender) has the blue wire connected to it, and the R connector (closest to the drivers side fender) has the white wire connected to it. The blue wire should also be on the voltage regulator terminal closest to the drivers fender, and the white wire (which gets spliced to an orange one) ends up on the second terminal on the voltage regulator right next to the blue wire.
When you got 12.5 Volts at the horn relay what was the voltage at the alternator output terminal (car has to be running)? If it wasn't 12.5 Volts plus a little then the wire that comes from the alternator to the horn relay terminal is open circuited.
The output wire from the alternator is spliced to the red wire that goes to the battery terminal, and the horn relay, as well as the main power feed to the fuse panel at a fusible link. It's possible that the fusible link blew and open circuited only the red wire from the alternator output terminal to the fusible link, while leaving the other three wires connected. Since you got voltage to increase to 13.4V by jumping the Field terminal to the battery, this wire shouldn't be open.
Maybe it's just a bad voltage regulator, or the voltage regulator isn't grounded. Make sure you get a good ground from the radiator support to the case of the regulator.
1969 Indy Pace Car
350/300HP RPO Z11
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.