Alternator Wiring question

[timmj68]

Was having trouble with the alternator the other night so I decided to replace it and the battery and cables since they are old and rough looking. I removed the alternator and started digging into the wiring and found a wiring mess underneath all of the electrical tape. I can't believe how many wires have been spliced and soldered together. The question I have for my Bronco Brothers is this - does anyone know which colors go where? I know there are three wires I need to connect but I only have two that I know for sure are correct. The third wire broke loose from the back of the alternator while I was taking it off and there were so many wires that were just terminated without a connection that I really don't know which one it should be.

Thanks for the help, MT

 

[Terkish]

Man that looks like a mess. I hate dealing with PO's wire issues.

So from what gather on a factory set-up you should have a black/yellow line wire to the main Batt connection on alt. this wire will be biger gauge then the others. Which i think is in the top left of your pic. then that orange wire should go to the Fld connection on the alt. Then there should be a Grd connection wire in there some where original color would be black/red line. I don't see that in the pic. Hope that helps and i hope you can figure out what all the other stuff is. I would try and get rid of the extra wires if they don't go to anything. Good luck.

-Clint

 

[Terkish]

Also it looks like some of that wiring should go to the starter solenoid. Where the wires come out of the wrapped area of the harness.

 

[70_Steve]

The question I have for my Bronco Brothers is this - does anyone know which colors go where?

http://seabiscuit68.tripod.com/

 

[timmj68]

Thanks Turkish and Steve. I've got everything sorted out and hooked back up, everything is running fine.

One thing I noticed though, after replacing my alternator my ammeter gauge is bouncing around, it wasn't doing that before. Any ideas why it would be doing that? The new alternator had a sticker on it that said I should replace my voltage regulator when replacing the alternator. Is that a requirement?

 

[Steve83]

...does anyone know which colors go where?

Are you going to tell us what YEAR the truck/wiring harness is?
.

...my ammeter gauge is bouncing around, it wasn't doing that before. Any ideas why it would be doing that?

A poor connection, most likely. How long has it been since you inspected/cleaned the double-bullet connector in the main power wire at the ammeter loop?

The new alternator had a sticker on it that said I should replace my voltage regulator when replacing the alternator. Is that a requirement?

No, but it's certainly a good idea. If you haven't already swapped to a modern electronic version, this would be an excellent excuse/opportunity.

 

[70_Steve]

One thing I noticed though, after replacing my alternator my ammeter gauge is bouncing around, it wasn't doing that before. Any ideas why it would be doing that? The new alternator had a sticker on it that said I should replace my voltage regulator when replacing the alternator. Is that a requirement?

No, but it's certainly a good idea. If you haven't already swapped to a modern electronic version, this would be an excellent excuse/opportunity.

Does the ammeter bounce all the time or is it most noticeable at idle. At idle do you also see the headlights getting brighter and dimmer???

The stock voltage regulator is electro-mechanical, meaning it's got relays inside. To keep the battery at the proper voltage, the regulator is constantly applying and removing voltage from the field winding in the alternator. When voltage is applied to the field winding, the alternator creates current. When the voltage is removed from the field winding the alternator stops charging, and the current is supplied by the battery.

As Steve83 suggested, a nice upgrade for the stock 1G is to used a solid state voltage regulator. It will all but eliminate the bounding ammeter and flickering headlights at idle. The application that comes to mind is a 78 Granada...