I am having a problem with my charging system, that I can't diagnose. I am hoping that someone can remotely troubleshoot this. I have a 72 Ranchero with a new 429. This is the typical project car. Used to have a 351C. The battery is not charging, and ultimately drops to around 8-9 volts and will no longer start. The battery is BRAND NEW, 1000cca, and is good. I have brought it back to the store, where they re-charge it and say its holding a charge. I have also swapped another known good battery in there with the same results.

I replaced the alternator with a NEW alternator. When I take it to Autozone, they put the tester on it (while in the car) and it is only putting out about 4 amps. WAY too low. When I take it out and they bench test it, it puts out about 50 amps. The alternator is GOOD.

So, I decided to keep throwing my money away and buy a new voltage regulator. No difference. The battery cables are BRAND NEW (1 gauge). The tension is tight on the alt belt. So, I decided to re-wire the alternator/VR connections, thinking the wiring is at fault. Here is how they are wired:

I : Goes to the wiring harness near the solenoid. Goes to a green/black wire (I believe the ignition?)

A : 2 wires come out from this lead. One goes to a capacitor/condensor thingy on the VR itself. The other wire goes to the BAT post on the alternator.

S : Goes to the Stator lead on the alternator

F : Goes to the Field lead on the alternator

In addition, there is a ground wire from the alternator to the body.

Is my wiring correct? Did I miss something? I am running out of parts to replace!

Thanks in advance

Charlie

 

Can you trace it out from here to verify?

 

This soesnt look like my set-up at all. I don't have an electric choke, my volt reg is not electronic, and there is no wire going from the BAT connection on the ALT to the solenoid. Thats a nice simple diagram, though. Do you have one for a 72?

 

Yes but not handy & my scanner's acting up.

Sparky or Franklin should be by soon.

 

After reading through a lot of the threads on here...I have an additional, and perhaps related question. My batt cables (1 gauge) are set up with the positive going to the solenoid and the negative to the block. Do I need an additional ground from the block to the frame?

 

anyone know if this voltage regulator wiring is correct?

 

Wiring is close but definitely not correct....check out this link to Franklin2's gallery....it should clear everything up


https://www.ford-trucks.com/user_gal...=16603&width=0

 

Thanks Sparky, but I have a few questions....My Volt Reg has 4 spades (I,A,S,F) and the one above has only 3 (no "I" spade). I also don't have an electric choke. Is there a way to get one of these diagrams that is applicable to my year? These are great pictures, easy to comprehend, but I think this one is for a different application.

Thanks

 

Ford was nice enough to keep the same basic system on its vehicles for quite a few years..................

I = if you have an ammeter it is not used

A= to Battery +, "BAT" terminal on alternator and noise suppression capacitor, reduces whine on radio due to AC power ripples on DC power so I have been told (Stock yellow wires)

S = 12 volts from ignition switch, as far as I can tell it turns the regulator on when key is in "run' (Stock green/red stripe wire)

F = "field" terminal on alternator, regulates field to keep alternator at 13-14 volts or so with the varying electrical loads (Stock orange wire...maybe has a blue stripe)

STA= stator terminal (on alternator), used to power electric choke, if you have no electric choke it isn't used. (Stock white black stripe wire)

BAT = battery terminal on alternator....alternator voltage output (Stock black red stripe wire)

With "Idiot" Light
https://www.ford-trucks.com/user_gal...=28796&width=0

Without "Idiot" Light
https://www.ford-trucks.com/user_gal...=16603&width=0

 

Sparky, your last post was a BIG help! Looks like I was way off. I just have a few more clarifications, if I may:

1. If I am not using an ammeter, leave the "I" terminal on the Volt Reg disconnected.

2. The "A" terminal should go to 3 places: The positive on the battery, the BAT on the alternator, and the capacitor

Thanks again...I think I am almost there!

 

1. Yes

2. Yes.............. but when you run the large black/red stripe wire to the battery + terminal on the starter relay all you have to do is run the "A" terminal of the regulator to the same spot.
You do not need several long wires going to the battery + Electrically when wires hook two spots together they are "seen" as the same place.......I hope that makes sense

 

This sounds looks like the diagram you need.

 

That's it! Thank you Franklin2. From this illustration it is clear to me that there is NO connection between the BAT on the alternator and the ignition solenoid on my car...I went out and put one in and POOF! I was kicking out 45 amps/14.5volts. Thanks a lot!