Alternator and voltage regulator wiring help

[danno]

You must be registered for see images attach

Hey guys and gals.. I’ve been working on the wiring on the battery/charge side and in testing the alternator (which is new’ish) it was not putting out a charge voltage. I started tracing wires back to the voltage regulator and along with some very shoddy splicing I’ve noticed some strange disparities when I compare to the wiring diagrams i see online. My alternator I believe is a 1G with the little external square regulator. All the wiring diagrams show a [F]ield and tator wire going to the alternator but I only have one wire other than power and ground, it plugs into a two wire plug so there’s a terminal on the alternator with nothing going to it.. probably an easy fix that I can fix with a jumper but does anybody know which wires off the voltage regulator go to these two prongs on top of the alternator? Is this wire on the two prong plug for the [F]ield output of the regulator?

 

[danno]

This forum won't let me update this i don't know why the strikethrough is on the text and cannot seem to get rid of it..

 

[Cubey]

there is an edit feature

 

[Big Bart]

We have a simliar thread going on with some good info. Look about half way through the thread.

You should field test the alternator (Tell it to do a full charge and see if it is working. Then you know if you should chase the wiring and regulator or if the Alt is dead.)

1988 7.3 Electrical Challenge - Died while driving; non-start condition.

1988 7.3 IDI, 124,000 miles Has set 10 years. Restored to running condition recently. While driving, engine quit, pulled over, found negative battery post too hot to touch, disconnected it. Now, currently with: positive battery cables attached to battery and starter, and negative battery...

www.oilburners.net

Post any additional questions here, but your alt could have been set up as it is.

 

[danno]

Well the starter and alternator are fairly new and I just rewired the charging side and starter so I just think whoever wired up the voltage regulator the last time screwed something up.. I can’t understand why there are two terminals on the alternator and a two terminal plug but only one wire going to it.... maybe it’s because mine doesn’t need the stator hookup for a dash mounted ammeter/gauge?

 

[DaveBen]

You should NOT have two wires going to the alternator on the threaded post! Someone is using this as a + terminal and it is NOT. Remove the wire with the greenish blue wire and move that to a + battery terminal.

 

[danno]

there is an edit feature

Tried it I think it’s broken

 

[danno]

You should NOT have two wires going to the alternator on the threaded post! Someone is using this as a + terminal and it is NOT. Remove the wire with the greenish blue wire and move that to a + battery terminal.

I ran that second wire straight to the battery it’s the same circuit that the starter batt+ is on, but now I realize the 10ga wire to the starter solenoid is a fusible link... seriously thought they stopped using wire are fuse back on the 50s .............. but anybody know what the two spades on top of the alternator are? Is one for the stator connection for a dash mounted ammeter?

 

[IDIBRONCO]

You only need the one wire that's in your plug to make the alternator work properly. That is as properly as the 1G alternators can work. What does it go to? I'm not sure but it's probably the regulator since the alternator won't charge without that wire hooked up.

 

[Cubey]

You only need the one wire that's in your plug to make the alternator work properly. That is as properly as the 1G alternators can work. What does it go to? I'm not sure but it's probably the regulator since the alternator won't charge without that wire hooked up.

Yep, the plastic spring on that connector is bad on my RV. 2 years ago i "fixed" it with a zip tie though to keep it from vibrating out and since then it's been fine. When it was working itself out, it would disable the alternator. Mine has two wires, if I'm not mistaken.

 

[Big Bart]

I having just one wire is not an issue. Many Fords are wired this way.

The F wire runs from the regulator to the alt. It regulates how much power goes to the alternator field wiring as I recall. The higher the voltage the reg sends to the alt field the higher higher alternator amp and voltage output.

You have the fusible link (Usually goes from the + terminal on the alt to the starter solenoid and back feeds from there to the batteries to charge them.) but the green wire on the +post on the alt I don’t believe is factory Where does the green wire go? (Guessing starter soleniod or some kind of trailering wire.) But if it goes to the starter solenoid, not sure why they put two charge wires. One concern is if that creates a problem with feedback or reverb causing the regulator to not work properly.

You could trace all the wiring and check for resistance and voltage. But it would be easier to remove your alt and reg if you have a auto parts store nearby and have them tested. Then you might find one or both is bad and if replaced your up and running again.(I suggest you replace the regulator out of principle if the alt is bad.)

If both are good here is a video that might help you test the wiring.

xc_hide_links_from_guests_guests_error_hide_media

Let us know how it is going.

 

[danno]

Thanks for your help guys consider this one FIXED .... ! Back on the road.........

 

[IDIBRONCO]

So what fixed it? Since I'm an electrical dummy, I don't think that I would have had the patience to do all of this. Especially after finding out for myself how easy a 3G swap is to do. Props to you.