Thanks Moto Hero for posting pic. Do I need to explain pics?

No power to the green S wire on the regulator.

Solid state regulator, only thing connected is the radio suppressor. All stock wiring and factory components

 

Thanks Moto Hero for posting pics. Do I need to explain pics?

No power at the voltage regulator S terminal green wire.

Solid state regulator, only thing attached is the radio suppressor

 

Good. Sounds like you have the more "modern" setup then. I think Ford changed from the more archaic early style in about '70, or more likely in '71.
So yours is fairly simple, and should follow the usual wiring scheme for ammeter equipped trucks. I have been meaning to grab a page from Fordification to see if they have a '72 diagram, but never have much luck finding them.

Anyway, with an ammeter instead of a warning lamp, your three wires at the regulator should be:
1. F position: Field wire is Orange and runs directly to the FLD post on the back of the alternator.
2. S position: "Switched" (it's actually for "stator" but I use switched in order to remember it's function) should be the Green w/red stripe wire and comes directly from the ignition switch. Should have 12v on it ONLY when the key is in the ON position.
3. A position: "Always" (it's actually for "armature" but always is what I call it to make it easy to remember) is full battery voltage at all times. It's spliced into the harness near the starter relay/solenoid. Typically tied into the large Black wire.

So Orange will give different readings at different times, so I've never actually tested one.
Green w/red should have switched power and should be as close to battery voltage as possible.
Yellow should be battery voltage.
If either of those last two have much less than battery voltage, the wires are compromised.

With no power on your Green w/red wire, you need to dig down and find out why. Likely has to do with the rest of the burned wires at the ignition switch, but since it sounds like much of the wiring under the hood has been messed with, you may need to keep digging well beyond just the switch.

Paul

 

Do you have this wiring diagram?

https://www.fordification.com/tech/w...rWiring_02.jpg

In the upper right corner, look for... 904 G-R, under that you will see S 5.
904 G-R is the wire that goes to the "S" connection on the voltage regulator.
932 B Goes to your throttle solenoid. I believe you said that it wasn't working, no power.

The power input wire to S 5 (splice 5) is 16 R-G from the ingition switch, which is key ON power. I wish I could tell you where splice 5 was, but I don't know. It would seem that it should be fairly close to the ignition switch. Just follow the 16 R-G from the ignition switch. It would seem that splice 5 is where the bad connection is.

Here's the ingition switch diagram link....
https://www.fordification.com/tech/w...rWiring_03.jpg

There at 2 wires sharing the same key ON output from the ignition switch. 16 R-G and 16A PK. As it seems there is only one position that has 2 wires in the same hole, this should make it easier to find.
16A PK is the feed to the coil positive, via the resistor wire.

Hope this helps, Jim

 

Wiring diagrams seem to be inconsistent the Fordification and the one I had gotten from Autokrafters, they both show different colored wires between them, and what is in the truck is different also from either schematic making tracing wires a guess

Yes as an example I have a green/yellow wire tied into the terminal with the heavily insulated pink wire (the green/yellow is burnt) there is also a red/blue wire in the ignition plug but no red/green wire

Wire 932b is the switched 12v that I want to run the MSD power from and it is dead.

Have a electrical wiring expert coming over next week. Will let you know the results

 

If feel your pain regarding wiring changes. The wiring diagram are more suggestions or guidelines.
As only one output of the ingition switch has 2 wires in the same hole I would focus on those 2 wires, one going to the Coil, via the resistor wire, which is usually pink and has a rubber feel to it. If your resistor wire is burnt, it might have a crispy feel to it.

Look for a common point. For example ... If nothing is power by either wire it's probably the ingition switch or the connector on the back side.

Good luck. Jim

 

Wire 132 B and wire 16 PK are only use for "LITES". I believe this is referring to a CHARGE LIGHT, instead of an AMP Meter. Or a better definition is idiot lights instead of gauges.

Your wire numbers are 16 R-G and 16A PK, because you have an AMP Meter.
The pink wire most likely has a lot of heat damage, changing it color darker.

If the Red Green wire (meaning the wire that's supposed to be R-G) is in better shape you could use it for all 3 of your needs. Meaning the trigger wire for the MSD, voltage regulator "S" input and throttle solenoid on the carb.
Good luck, Jim

 

But how to repair the red/green where the spade is locked into the hard shell connector?

pics to follow

Have a spare dash harness for a 70 and got to unraveling the tape to learn more of the wiring. The red/yellow wire and the pink resistance wire pinned together at ignition plug are the problem. Following the red/yellow it goes to one of those round wire splices and comes out with the green/red voltage regulator S wire and the blue carb solenoid wire both of those are dead. That connection seems to be the problem.

If you scroll up to the pic of the engine firewall you will see a 3 pin plug there is the pink wire on the lh coming in to the plug and a red/yellow coming out that was feeding the + side of the coil.

Jim, is there another wire on the switch or elsewhere that I could use to power these wires?

 

 

It seems you are making progress, unfortunately most on my hands ON experience is with newer trucks. But I will add some general thoughts.

Others have posted that the SPADE pins are removable. There's a release that you use a small screwdriver to move a tab, (tabs?), then the Spade pin will pull out.
Others have posted that a long time ago NAPA sold replacement Spade connectors.

Are you sure that the failure is not internal to the ignition switch itself?
I prefer to use a 12 volt test light for troubleshooting. It loads the circuit a little and is easier to see the bright light, compared to reading the voltmeter.
With the test light stuff in the hole with the 2 wires, is the anything coming out of the ignition switch when you turn the key ON?
If there is power coming out of the switch, going to the splice, you really don't need to mess with the switch at this point. The rubber that is covering the splice can be cut away to inspect the splice, but it might not be worth the effort. You could just replace it with a Blue butt splice with 2 wires in each end.

Going forward, I would avoid using the Pink resistor wire for anything. On your original MSD install it was used for the "key ON trigger" because it was easy to get to.

The fact that the ingition switch shares 2 wires in one key ON output, tells me there's not really another source for key ON power out of the switch. But I really don't know.

By chance did you mount the MSD box near the battery or voltage regulator?
You could tap into the green wire going to the "S" on the voltage regulator for the trigger input to the MSD box. Instead of relying on the resistor wire, which might be damaged.

None of the 3 things you need key ON power for are high draw items.

Thanks for the photos, it really helps.

Jim

 

Have a new OEM FORD switch and tried it with that and the old switch no change. Yes I am using a test light for this only use the voltmeter to test battery. The MSD box is mounted on the rh fender apron, using the green/red S wire on the voltage regulator would work possibly but that wire has no power and the alternator is not charging because of it

 

Quote...
But how to repair the red/green where the spade is locked into the hard shell connector?
This truly is the next thing to figure out. How to remove, inspect replace the connector.

My point was, going back together, it would be easier to leave the pink wire out.
Use the other wire to power all 3 items.

If you are unable to get new connection, you might have to remove one from your spare harness. Like say the single red wire, assuming the connector is the same size.

Run this to the splice you are going to replace... with a blue butt splice.

Jim

 

https://www.dennis-carpenter.com/tru...pigtail-wiring

It looks like the replacement connector only has single wires(6).
None are double stacked into a single hole.
There's lots of places that sell this connector.

https://www.clipsandfasteners.com/Ford-Ignition-Switch-Harness-Connector-p/a19881.htm

Jim

 

In this photo you can see the "release tab"
It is on the bottom (flat side) of the connector.
You push a small screwdriver in to lift the lock tab up.
.

 

Replace the ignition switch with one from autozone, now have power to the terminal with the bad wires. Used a small screwdriver and was able to remove the spade from the hard shell. Thinking I should cut the pink of the connector and get as much of the red/yellow as I can and splice a wire to it and run it through the firewall and use it to power the msd. Should I tee off of that and splice it into the green/red to the S terminal wire for the voltage regulator??