new alternator not charging, rogue wire?

thanks for all the help in the past; here's another one that i hope will be an easy one. actually, i have two problems - but i'm hoping they're related. this is on a '76 bay backfitted with an upright from a '74 super.

just replaced my alternator with new bosch unit (internal vr - the original had external vr). whew! much more work than i had planned, but the new one is now in place. i followed the included instructions to convert between external vr and internal and am pretty sure it's hooked up correctly now. however ...

i see no voltage difference between running and non-running (across the battery as well as from alternator B+/GND. okay, so the alternator is spinning but not charging ... i read somewhere that the alternator warning light must be lit in order to get enough current through the alternator to get it started. lo and behold, the light is not lit. i have continuity across the light leads so i know it's not burned open. i'm having a hard time understanding where the other end of the light's wire is going, which leads me to the next potential problem.

i labeled (i think) everything that i disconnected, and yet now that everything is reconnected i have found a rogue wire and can't determine what it's supposed to be connected to. could this have anything to do with the alternator and its warning light? it's white/green and is routed to its spot beside the coil along with a black wire that connects to coil positive. as far as i can tell, the bently manual doesn't mention a white/green wire at all. it does mention green and light green. after 30 years of engine oil and heat, i'm surprised any of the colors differ from brown/black.

so my questions:

1) is the alt warning light indeed required for the proper operation of the alternator, and if so where do i go from here?

2) can anyone identify the white/green wire in the engine bay and tell me what it's supposed to connect to?

as always, thanks a bunch!

Reply to
Dewey Hylton
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The rogue wire may be for the diagnostic socket. See: "What is this plug in my engine bay?" on my web site.

The GEN light wire is solid Blu and should have been connected to the old regulator on the firewall. The wire comes out of the main harness on the right side of the engine bay. If you ground that wire, the GEN light should come on (key On). After you identify the wire, connect it to D+ to the Alt.

Speedy Jim

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Reply to
Speedy Jim

woohooh, light! and charging! though i'm only getting just under 14v no matter what the rpm ... does this sound correct? everything i've been reading says the lights'll go brighter and the voltage will go up when i rev the engine.

Reply to
Dewey Hylton

The Alt starts charging even at idle. Your reading may be completely normal. Might not even notice lights dimming/brightening.

Jim

Reply to
Speedy Jim

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