No, the one you took the wiring harness out of had a G1 alternator on it.
You have the Fire prone (They burn up a lot of trucks or melt the plug) 2G Alternator.
For more information go here:
http://fordfuelinjection.com/index.php?p=63

 

Does this wiring diagram match your old wiring harness? This is a 2g alternator.
http://www.fordfuelinjection.com/pub...ALT_wiring.gif

Here's a picture. Is this your alternator? It's also a 2g
http://www.fordfuelinjection.com/pub...ternator02.jpg

 

Its not quite like that. The plastic plug has three wires going into it, and above that there is a bolt with a single wire attached to it. I thijn kthat ios all the wires that are attached to it. I can take a picture of it tomorrow. There is a sticker on it that say remanufactured 100 amp.

 

This a picture of the alternator in my truck.


Th wiring harness I got had an alternator that had just 3 wires that attached on the back of it. Which I think you described as a G1.

What do I need to do to make the alt gauge work properly? I have all the other stuff figured out to make the cluster work.

Do I even need to attach any wires to the alternator or would I attach tham to the wiring harnes itself?

 

You have an odd alternator. Some sort of high output model, since the normal alternators where only about 60-75 amps. Did this 100 amp alternator have an external regulator? Can you clean the wires off really good and figure out what color they are on the 100 amp?

You do not have to do anything to make your ammeter guage work. It's already wired into the harness you got at the junkyard.

 

I'll have to check on the regulator and wiring colors today and post the results.


I'm still confused about the wires for the alt gauge. I have the harness from the truck I got from the salvage yard which is wired correctly for the alt gauge. The connections at the alterantor is different than what is in my truck. This is what is confussing me. Maybe after figureing out the wire colors it will make more sense.

 

There is a external voltage regulator.

The wires on the alternator are as follows

The top wire thats held down with a nut is a black wire. It attaches to the hot side of the solenoid.

There are 3 wires that plug into the plastic connector.

One of the wires goes to the electric choke.

One wire is orange/blue stripe that connects to the F connection on the voltage regulator.

One wire is White or Tan/ black stripe that connects to the s connection on the voltage regulator.

 

I changed the connector on the harness today and wired it up for the new cluster.

The tach now works!

The only thing left is to get the alt gauge to work.

 

When you wire it in do not forget to include a shunt.

 

Okay you lost me, It's only been 25 years since I've had electricity class in high school.

Would there of been a shunt wired in the original wiring I got from the salvage yard?

I looked at the wiring diagram you sent me subford but not sure how to read it.

 

Yes if you got that section of the wiring.
Make sure you wire the Regulator for a gauge.
Red/LB control wire to the "S".
Yellow/White Dot from "A+" of regulator to Black/orange at Fuse link splice.
"I" on Regulator not used.
"F" on Regulator Orange/LT blue to "FLD" on Alternator.

 

The shunt should be in the new junkyard harness if it was all original. Going by memory, the large output wire coming from the alternator does not go directly to the solenoid + connection on the new harness. It goes over to a splice, and then as it makes it's way over to the solenoid + connection, the shunt is located in that area.

What subford said is correct on how the regulator should be wired, but that also should just plug in and be correct already with the new junkyard harness. Where you are going to have to do some rigging is with the plastic plug on your alternator. You are going to have to snip the wires, and connect the "F" wire from the new harness to the "F" wire on the alternator. The large output wire should bolt on like the other harness, and the choke wire should hook up to the same wire. You do not need the wire that goes from the alternator to the "S" on the regulator.

 

Now I'm starting to understand what your saying. I have the complete harness from inside the cab and engine compartment. I'll take a look at the harness after I get off work today. If needed I'll take a picture of the harness in the solenoid, voltage regulator, alternator area and post it to make sure that it is wired correctly.

Thank you guys for being patient with me for asking what seems like the same question over and over.

I want to do it right the 1st time without melting all the wires together in my truck. I haven't even got to drive it yet!

 

All right, I took the tape off the small harness that plugs into alt. and voltage regulator. I took a picture of it, so take a look and see if this looks correct.



There is a few wires that are spliced and additional wires tie into them. It looks to be wired just as subford described.

The black/orange wire from the alt comes up and is spliced with a black/orange, heavy yellow wire (goes to fuse box)and yellow/lt green (alt connection on cluster). The black/orange wire continues up and has another splice with a yellow/white dot wire (A terminal of regulator) and a red/orange wire (goes to alt connection on cluster). The black orange wire then attaches to the hot side of the solenoid.

I assuming this has the needed shunt wire?


Now on the original wiring there is a green/red wire attached to the I terminal at the votage regulator. You stated that this is no longer needed. (I think it went to the idiot light on cluster) But on the salvage yard connector for the voltage regulator terminal S there is a green/red wire attached to it also. Does this need to be used and where would the wire attach to inside the cab?

There is a yellow/white dot wire that attaches to the A terminal of the voltage regulator that has a exttra wire with connector. Does this connnector need to have the capacitor type thing attached to it and it grounded to the truck? The truck I got the wiring from didn't have one but another truck did, so I took it just in case I needed it.

 

I see a shunt in the wiring, it is the large black looking wire that is folded back on its self.

Here is a diagram of what you are wiring.


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