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Old Feb 13, 2010 | 01:30 PM
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alternator wire help

It looks like I've made a mistake, I forgot to mark the alternator wires when I took it apart... Now I'm stuck, and I can't figure out where the wires go. I just took this picture, maybe someone can help me match the terminal to the wire...



Thanks


Sam

P.S. There's more terminals than there are wires, is that something I should be concerned about?
 
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Old Feb 13, 2010 | 03:05 PM
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Red grommet to FIELD

Ring terminal to BAT

There should be a 3rd wire that slips on the STATOR terminal.

The wiring harness strap connects to the 7 o'clock stud.

Josh
 
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Old Feb 13, 2010 | 03:42 PM
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Ok, thanks! What should I do about the missing wire though? Maybe that's why the last alternator cooked itself?

Sam
 
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Old Feb 13, 2010 | 03:54 PM
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It should be there...

Do you have the dash with gauges or idiot lights?

With gauges the wire should be there. Otherwise you could run a new wire from the Stator terminal to the S post of the regulator.

Josh
 
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Old Feb 13, 2010 | 04:47 PM
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I've got gauges, the only lights on there are for high beams, brakes and turn signals.
Where is the S-post on the regulator? Is it one of the clips, or...? Sorry for so many questions, I don't know much about electrical stuff.

Sam

P.S. Is the missing wire a must have for the alternator to work properly?
 
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Old Feb 13, 2010 | 05:32 PM
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It's the post marked STA on the back of your alternator and no it will not work properly without the wire. The wire goes directly to the S post on the voltage regulator.

If the wire is still in the harness it will be white with a black stripe.

And don't worry about the questions, it's what we are here for. And once you get this nailed down you'll, in turn, be able to help somebody else.

Josh
 
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Old Feb 13, 2010 | 06:30 PM
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Ok, I found the S post, so should I just solder the stator wire to the wire coming plugged onto the S-post? There was no white wire anywhere in the area, a few yellow ones (I'm pretty sure they were yellow to begin with, not just yellowed over time.) Looks like I'll have to run a new one.

There was something else too, there's no wire for the F post on the regulator, there's a spot in the connector, but no wire in it.

Sam
 
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Old Feb 13, 2010 | 07:25 PM
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From your picture, the orange colored wire with the red cap goes to the F terminal of the voltage regulator.

Did you just get this truck? Sounds like the wiring has been seriously hacked into for some reason.

Josh
 
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Old Feb 13, 2010 | 08:08 PM
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This is the same one I've been working on for awhile. I just went out and double checked it, and its the l post that has no wire, not the F post, the F post has the dark orange wire like you said. Looks like I got them mixed up somehow...
Sorry about that! But, then what is the l post for and why doesn't it have a wire? And before I solder the stator to S post wire, there's is one wire that plugs in there its green-ish yellow with a red stripe, should I just solder the stator wire into that one?

Thanks

Sam

P.S. The truck did have an engine swap a number of years ago (1984 or 85 I was told) so mabe that could account for the missing stator wire.
 
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Old Feb 13, 2010 | 08:19 PM
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Mine didn't have a wire on the "I" terminal of the regulator either.
 
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Old Feb 13, 2010 | 10:22 PM
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Ok, my new alternator is in and the truck is running! I soldered the wire in and hooked it up to the stator terminal. Thanks for all your help!

Sam
 
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Old Feb 13, 2010 | 10:25 PM
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Be sure to check the "running" voltage, it should be anywhere from 13.2 to 14.5 volts.

Glad things worked out.

Josh
 
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Old Feb 14, 2010 | 06:40 PM
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Ok, which terminal on the alternator should I clip it to? the BAT? then run the other clip directly to the positive side of the battery?

Sam
 
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Old Feb 14, 2010 | 07:18 PM
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No, at the battery would be the best place. You can check both, at the + of the battery (or solenoid post) and the alternator to see what difference, if any exists.

Check at idle and with a fast idle (1500+) with lights off, no heater and then check again with lights on and heater on hi. This will check the running voltage of the alternator and what load is placed on it with accesories running.

Josh
 
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