GM 3 wire alternator on 1980
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GM 3 wire alternator on 1980
I have been trying to find out how to correctly wire a GM alternator on my truck. I got the TG bracket and the 3 wire alternator. I read thru about 100 pages of postings. Read all of the too_cool_3's how to, but he sez that there's only three wires to deal with.
I spent about 3 hours reading build threads and still couldn't get the answer.
The problem for me is that there are 6 wires on my plug. I am not sure if I only need to use the Yellow and white and leave the others disconnected or what.
I know I need to connect a large cable to the battery from the post on the alternator.
So the question is about the six wires on the harness plug.
I spent about 3 hours reading build threads and still couldn't get the answer.
The problem for me is that there are 6 wires on my plug. I am not sure if I only need to use the Yellow and white and leave the others disconnected or what.
I know I need to connect a large cable to the battery from the post on the alternator.
So the question is about the six wires on the harness plug.
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It's the alternator that is three wire. It's supposed to be really simple which is usually something I can handle.
I do have the diagram in a Haynes manual but I was hoping somebody that has done this in a 79/80 would have the "simple" solution.
All the builds I have read seem to be on 1984 up. My pic is of the stock plug that goes to the rectifier. The colors are; White, blue, green/white, red, yellow/white & black.
I haven't done any wire changes so everything is stock wires and plugs.
I do have the diagram in a Haynes manual but I was hoping somebody that has done this in a 79/80 would have the "simple" solution.
All the builds I have read seem to be on 1984 up. My pic is of the stock plug that goes to the rectifier. The colors are; White, blue, green/white, red, yellow/white & black.
I haven't done any wire changes so everything is stock wires and plugs.
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That's why I posted this. Everything I've read is for newer years. I will take some more time researching and get back. Thanks for the help so far.
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I checked your build and you have a four wire alt. I may be able to use some of your wiring.
Wire sizing is my guess, best I can figure out from the Cylmer wire diagram;
White 8ga. power lead to battery
Blue 8ga. ?
Green/ white 14ga trigger for alt.
Red/white 14ga changes to Black/yellow in harness
Yellow/white 14ga warning light
Black 14ga Ground?
Wire sizing is my guess, best I can figure out from the Cylmer wire diagram;
White 8ga. power lead to battery
Blue 8ga. ?
Green/ white 14ga trigger for alt.
Red/white 14ga changes to Black/yellow in harness
Yellow/white 14ga warning light
Black 14ga Ground?
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#8
The factory alternator is externally regulated and the GM alternator is internally regulated. Have you removed the voltage regulator? Because that is where you start.
If I recall correctly, here's how it goes:
GM alt "L" - Charge indicator (should be yellow wire)
GM alt "F" - Hot source when ignition is on (should be red wire)
GM alt "S" - 12v sensor (should be wire wire) or To Jumper to (+) on GM alt
GM alt (+) - Battery (you need a fuse in here somewhere)
It is technically a 4 wire, but I suppose they don't count that jumper wire.
If I recall correctly, here's how it goes:
GM alt "L" - Charge indicator (should be yellow wire)
GM alt "F" - Hot source when ignition is on (should be red wire)
GM alt "S" - 12v sensor (should be wire wire) or To Jumper to (+) on GM alt
GM alt (+) - Battery (you need a fuse in here somewhere)
It is technically a 4 wire, but I suppose they don't count that jumper wire.
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I haven't taken anything apart yet.
First of all I don't have room to have a big immovable lump of Toyota in the way because ...
Second, I am doing a major remodel of five rooms in the house and...
Third, I don't want to start ripping into something until at least I have a good idea where I am headed.
I know that I will be pulling the regulator and maybe that is what most of the wiring is about. A few years ago I nearly burnt up my CJ5 with a minor wiring screw-up on my part. I don't want to do that again either.
First of all I don't have room to have a big immovable lump of Toyota in the way because ...
Second, I am doing a major remodel of five rooms in the house and...
Third, I don't want to start ripping into something until at least I have a good idea where I am headed.
I know that I will be pulling the regulator and maybe that is what most of the wiring is about. A few years ago I nearly burnt up my CJ5 with a minor wiring screw-up on my part. I don't want to do that again either.
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