Made 350 to 455 switch in 69 Sky. Motor is running and car is drivable bu gen light is on with car running. Took alt to parts house and had tested they said it is good. What else could be wrong? Battery is brand new. I tried switching regulators with a spare. Battery keeps running down.ou:
discharging check the wiring harness / plugs where it attaches to the alternator . had a similar problem & that is where the prob originated . u may have to unwrap the wiring harness all the way back to the firewall & look for broken/shorted wires . when u turn the ignition off , does the gen light go out ? also , this question has been addressed on this site , before . try the search option . check the "wires to coil" thread in this section .
If it is good I supect the alternator is not online with the rest of the cars electrical circuit. Perhaps an in line fuse, a disconnected or broken wire from the output side or corrosion at a terminal junction would be by next suspect.
Alternator Question Two quick checks with out tearing the car apart. First make sure you have 12 volts the the large termial then follow the resistor wire (thin brown wire off the alternator) and make sure there are not any breaks in that. I would not unwrap the wires at this point but check for continuity on the charging curcuit. If you need your wiring draw out I have one for your car. Also there is another opition, do like I did and use a self exciting single wire alternator. This has the regulator built in and is quieter and more relyable the the old point type alternator. AL.
