Voltage regulator smoking?

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VanPhin said:
I’m not sure if my bulkhead connector is bypassed I will take a closer look
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The FSM will show you a drawing of the bulkhead connector and have a key for which wire goes in which cavity.

You can also begin at the starter relay. The stud forms a junction for three wires. One from the battery, one to the the bulkhead connector (includes the fusible link) and one to the horn relay. See if there is one to the the bulkhead, and does it have a fusible link. Oriignal fusible link is blue and has a tag hanging from it. Replacements may or may not have the flag.

Here's two fusible links (reproductions).
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Each have one end that goes into the bulkhead connector.
The other end of the top link goes over a stud. This was used on models where the starter relay was close to the bulkhead connector.
 
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That's a big help to us.
Someone "upgraded" to 1970s ignition and alternator.
Ignition is not the issue, at least not directly, so lets focus on the alternator and alternator circuit.

Regulator.
This reg is used with a "grounded field" alternator.
Field is short for electromagnetic field. The electricity for the electromagnet is supplied through the regulator.
There's more of an explanation in the "sticky" thread about Identifying Alternators".

The white arrow points to the points. The upper points allow maximum current flow to the alternator's rotor. So if the arm is stuck in that position, that's the cause or at least part of it. Normally, as voltage goes up, more electricity flows through the copper winding and the electromagenetic pulls the arm down, interupting the circuit.
Powe out of the regulator should be through the green wire as shown. Power in should be from the ignition run (blue) and someone has changed the wire. Red wire's connector looks heat damaged.

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This alternator is normally used with an "isolated field" regulator.
There are two brushes that go to the rotor. On an isolated field alternator, both brushes and their terminals are insulated.
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When using this type of alternator with the grounded field regulator, one of those terminals, or the wire connecting is grounded. Pretty simple modification.

It looks to me like the green wire from your regulator goes to one brush. If so that's ok. But the brown wire goes where?
With your regulator the brown wire should go to a solid ground. The alternator housing is best. But if goes anywhere other than a ground, then that's not right.

The other way to wire these is use a regulator where both wires connect to it. The sticky explains that. Since we see no other regulator, no reason to get into that now.
 
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I'm not sure what we are looking at on the engine.
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The two resistors are a part of the 1970s era Electronic Control Unit (ECU) for the ignition.

Unfortunately when that was added, the factory wires and colors got changed, and one of those the Ignition Run wire J2 is shared with the to the voltage regulator. So you'll have to figure which wire that is, even if you don't touch the ignition.
 
Thank you so much for this information tomorrow when it is daylight out I will sort some more things out
 
We through alot at ya tonight.
I might tackle it by begining with following the circuit from the Battery positive to the key switch. Check all those junctions and the condition of the fusible link.
Check the line from the alternator output to the inside. The welded junction is wrapped in the harness and probbaly fine. I'd leave it wrapped unless you have some reason to have to check it.

Then go investigate how the regulator and alternator got wired up.
 
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I checked the junctions and they look fine, the fusible link looked good too, I’m still a little unsure how the regulator and alternator are connected. On a better note none of the wires look completely destroyed but it’s still one hell of a spaghetti farm. I’ll do some more investigating soon it’s snowing pretty good here.
 
It's funny when I look at your pictures it seems that a bunch of wires are simply unwrapped (probably in search for issues in the past). Maybe someone here has pictures of your harness all bundled up and you could just re-wrap some in the groups like the factory. Or maybe there is someone near you that has a eye for these cars and could help you figure it out
 
I bought a new voltage regulator and installed it. The starter has power and it looks like certain wires have power. What I’m wondering now is it could be a problem with the bulkhead connector or the something with the key the dome light isn’t coming on and the headlights aren’t coming on as well. I don’t know what this thing is but on a better note most of the wires look ok

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You have been given great advice from some knowledgeable members here.
I just rewired my 64 Valiant this summer. With the help of a friend. It was really easy.
It looked about what you have. 60 plus year old wires, that god only knows how many shade tree mechanics had their hands in.
I bought this setup. Under $500.00 if you have that much to invest. Simple as he'll to follow, and they answer any questions you have and walk you thru them.

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VanPhin said:
If anyone would like any photos or has any suggestions/questions please ask
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Your wiring has been hacked up. There is no way we can guess. EG the brown going to the alternator field is OEM green. It is a simple wire, and goes from the field connector to the F connector on your VR, no other place. That alternator is later, 70 and later, which has two field connections and is known properly as "isolated field," because the original to the car would have been "grounded field" and would have had only one field connector. The other brush in those days was grounded by the brush holder.

The circuit for the vr is dead nuts simple. You have ONE and ONLY one switched 12V from the ignition switch, that is "hot" in the "run" position, dark blu. That branches off somewhere between the bulkhead connector and the ballast resistor, and also feeds the VR, terminal marked IGN for "ignition." The VR MUST be grounded.

BEFORE I GAMBLED and connected a brand new VR I would do some tests.

1...READ THE MANUAL which at least two of us have suggested. There is a part of section 8 (electrical) which deals with measuring field current. IF IT IS NOT in the earlier manuals, go back to MyMopar and download a later manual, say, 69. What you are looking to do is determine the current draw of the alternator field and whether it is shorted

2....Now connect everything normally EXCEPT the VR. See if the car starts and runs normally, that there is no smell or smoke from the harness. Check all your electrical accessories such as headlights, heater, etc, turn signals and brake lamps, etc. You will be doing this with the alternator NOT working. If that is OK......

3....Now, with the engine shut off, take the two VR wires, and jumper them together with an alligator clip lead, etc. This will feed 12V power directly to the alternator field and cause it to charge "full." Put your voltmeter on the battery and prop it up where you can see it. Start and run the car, slowly bring up engine RPM, and voltage at the battery should start to climb. Don't allow it to go over a max of about 16V

4...If that seems OK, then connect the VR, don't forget to ground it, and check for normal operation If the battery is "down" from sitting or cranking, you should charge it first with a battery charger. Once the engine is warmed ans has run long enough to "normalize" the battery, it should "run" at nominal 14V. If it OVER charges (higher voltage) post back
 
Did everything work before your "charging event"? Have you checked all the fuses? There is a chance that the fuses blew and that's how you avoided much wire damage.
 
everything worked great before the event I checked the fuses and they looked good but I took a closer look at the bulkhead and that is toasted

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OUCH!!!
Layson's has the piece in the firewall (installs from the inside) part# 316-46842... $119, but I presume that the wires in both sides are toasted too. The entire front wiring harness Headlights to the firewall is $392 and everything under the dash is $1120.
 
VanPhin said:
Does anyone know where I could get a new bulkhead?
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You probably can rebuild that one, unless the plastic connector housings are severely melted. You can buy the Packard terminals used in them. Search up some of Mattox posts, or maybe he'll chime in. He did a big thread on the different types and where to get them. The supply sources do change, though, over time.
 
I totally redid my dash harness as it would have been over $1k to buy MH. I bought and replaced all new wires and connectors where i could and used a couple spare harness' for templates and parts. Tedious but saved $$$.
It's probably been mentioned but get yourself FACTORY schematics.
Good luck
 
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