Evening group, 1986 IROC-Z, 305 TPI, 700R4.
Driving my car last weekend and glanced at the instrument voltmeter gauge and it read under 8 volts. Changed the alternator with a remanufactured alternator (108AMP). Bench checked replacement alternator, at 14 V output.
For a safe measure, changed battery out with a Duralast Gold. Got it checked out at O'Reilly's while running and the battery stored 12 V.
He checked the starter volts and they were in parameters.
Heard stories that if you put a new battery and alternator in it'll read low until the voltage regulator identifies a need to charge. Sounds like an old wife's tale. Car's reading just above 9V in the instruments. I had recently been detailing my entire engine bay and waxed the firewall and spray a light dust coat of bulldog to give a light sheen on the harnesses. Last night I cleaned the negative cable and reinstalled it, with no results.
My car usually read around 13-14 Volts. I cleaned the ground cable and checked for a loose starter cable...it's tight. Ran the motor and turned on the parking lights and they might as well be candle lights on a old horse and carriage. What am I missing here?:
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Is the alternator receiving excitation on the #1 terminal (roughly battery voltage on the #1 terminal in the plug with the key ON)? Note: Do not connect straight 12V to this terminal with an external jumper wire just to try it. There needs to be a current limiting resistor or bulb in that excitation circuit to prevent damaging the regulator.

Is the alternator receiving voltage sense on the #2 terminal (roughly battery voltage at all times the battery is connected)?

 

Excitation? I am definitely not electric savvy. Is there anything generally I can look for without the use of the OHMN meter? I'm sorry mechanic's is my strong point, but not electrics. I don't have any buddies that are electric system-minded as well...sorry for being so ignorant...Let me give you the scenario when I removed the bad alternator. The positive line to the alternator appeared to be missing a 1/4 of the connector eyelet. I replaced it with a aluminum connector I bought from O'Reilly's...this week I traced all the grounds and cleaned all connections on both positive cable and the negative cable as well...do you think that simply checking my fuse panel work. I have checked the wires and it doesn't seem that I have any breaks in the wirres. I also inspected the ground wire area on the right hand aft corner of the block, and cleaned the braided ground wire to the firewall just to the right of the braided line attach point. I was thinking about swapping a battery out of my work truck that is charging at 13-14 volts. Thought's?

 

If you're going to work on the electrical system of your car, or anything else for that matter, go spend $10-$20 for a basic multi meter. By all means spend more if you want, but it's not necessary to adequately cover the basics.

 

Okay, appreciate your response...let me get one. Have been looking over the wiring schematics and maybe have identified the issue. Since I have been detailing and painting the bay, the brackets and spacers on the alternator need to be grounded as well...the voltmeter gauge is fluctuating, which rules out the fuse and fusible links. Thanks again...

 

Check the plug that goes into the alternator too! maybe have a friend watch the voltage and push it in hard and wiggle it. I had the same problem once and I about pulled my hair out.......I was sitting in the car watching the meter and my husband was messing with things and all of the sudden the volts jumped up to just above 13. I asked him what he did and he said he just wiggled the plug and wires a bit

 

Yes, the plug contains the excitation wire and the sense wire. If the contacts in the plug aren't making good contact with the regulator terminals in the alternator it's not going to work very well.

I guess I jumped right to the multi meter suggestion on the assumption that one would check the contacts on the electrical plug/connection as basic troubleshooting.

 

Found the problem. No voltage from the alternator to the battery. On the positive cable, there's a terminal fusible link. The alternator wire simply backed out of the housing. FIXED

 

Thanks to all for your suggestions and guidance!!!