Voltage Regulator Connundrum, why won't the generator light come on? Options

[72 IXXIV]

So I was about to head up to McMark's for the BBQ a couple weeks back, got in my car and the red charging light was on before I started the car (normal) and after I started the car (a problem).

The fan belt was present and tensioned, so I hoped it was the voltage regulator and not the alternator.

I ordered a Hella regulator from Pelican Parts and while it would connect with the board, the relay board cover would not fit on. The plug on the hella is not in the same place on the regulator as the bosch one.

But since it connected (at least!) I gave it a try. Turn on the key, but not started, and no charging light. Turn on the car, still no light. But also no charging. Voltage across my battery is almost 12v with the car off, and 11.5 with the car on. No charging.

So I ordered a new Bosch voltage regulator, and just installed it. Same thing. No light with the key on and engine off (no oil light either this time!), no light with the engine on either. Still no charging across the battery.

Hey, maybe the bulb(s) blew? I put the original, broken regulator back in, both dash lights light up when the key is on but the car is off, and the oil light goes out when its on, but the charging light stays on. And no charging across the terminals.

What gives? Did I just get two bad voltage regulators? Am I missing something?

Thanks for your thoughts, folks!

[72 IXXIV]

Conundrum solved. It was the alternator. There was never anything wrong with my old analog regulator.

I did get THREE brand new voltage regulators (all solid state) that did not work. All of them failed to light the alternator light when the key was on but the engine was off.

Since the light energizes the alternator, it wasn't a valid test of whether the alternator was working or not--right? No charging could be because it wasn't energized OR because the alternator was dead.

So I went to EASY, where they told me that it wasn't the regulator, it was the alternator. However, I bought another analog regulator and voila--it acted just like my original one--light on before and after the motor starts. It was the alternator. Back to EASY where I got a used alternator.

I dug into the swap yesterday. Mark's tutorial on this site was a huge help! Figuring out that the sheetmetal has to move around quite a bit to get that bugger in there took me a second. After I got the carriage bolt in, I looked on the ground and saw the air gasket that's supposed to be on the front of the alternator. Practice makes perfect.

Key goes on, red light, engine goes on, no red light. Success!

Many thanks to everyone who chimed in with suggestions--especially that solid state regulators might not work very well. 3 brand new parts that don't work is hard for me to believe. That's how naive I am!