'83 El Camino - 305. New battery and just installed second replacement alternator (bench checked at store). All I show for output on both is 12.6V on my meter. What do I need to replace besides battery and alternator?

 

I'm unsure if the voltage regulator is integral to the alternator or a separate unit.
where are you checking voltage at, battery or alternator? You should check at both. If still just open circuit battery voltage at both, you need to check for power to the field coils. if you can locate a wiring diagram, I can help with the testing.

 

Other than the BATT post there's a two wire terminal which Chilton says is an integral voltage regulator connector - the Delco SI series for which I have a schematic. I've been measuring voltage at both battery and alternator post, using the frame for ground. Both show 12.6V - same as a fully charged battery which it is since I've been using the charger every day. That would mean the alternator is doing virtually nothing. When I watched the bench test at O'Reilly, it showed 14.7V output.

 

Is it a 4pin connector with 2 small wires and 2 unused spots and then the batt cable? what wire colours do you have a the alternator and in what sequence

 

It's a two pin only connector - facing forward, one brown on the drivers' side of the alternator; the other red on the passenger side - both on the two pin connector.

 

do you know how to do voltage drop tests of the insulated and grd circuits?

 

Did the voltage drop tests, everything turned on 2000 rpm - positive -0.02 negative -0.03. Cleaned both battery posts and cable ends - 13.3V at idle, no change with increased rpm.

 

where did you put your leads for each test?

 

Voltmeter + to Alternator B+/Voltmeter - to Battery + result -0.02V

Voltmeter - to Alternator case/Voltmeter + to Battery - result -0.03V

 

you did the test perfectly. Sorry I couldn't be more help.