1971 Slant-six ballast resistor ID

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French demon

French demon

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Hi guys

I have some questions about my ballast resistor.
Of course, I'm going to restore the connectors back to originals.

- Is this ballast resistor original, or at least correct for a 1971 Slant-six A-body?
- Is it in the correct location?
- Is it the correct holding down screw?
- Except the ballast resistor connectors, the wiring is original and untouched. Why do I have two dark blue wires and two brown wires? On the 1970 Dart engine compartiment wiring diagram (I don't have the 1971 diagram), there are two dark blue wires but only ONE brown wire.
Francois

Ballast resistor.jpg


BR location.JPG

Diagramme.JPG
 
Not sure but others with 71 knowledge should chime in today.
Nice clean looking engine compartment.
I'll just throw this out there...
It appears the 4 wires is for the 72 and up, 4 prong resistor. (that 4th wire is throwing me off).
Is that original wiring on your car?
I dont remember a ballast resistor mounted like that on a fenderwell, usually on the firewall.
Also, usually a 7/16" galvanized stubby self tapping bolt head holds them in place. (hard to see in pic, but this location is def correct).
Screenshot_20201223-054440_Gallery.jpg
 
:thankyou: Joey
If you're right, the correct location could be this hole into the firewall.
Ballast resistor.jpg


No, the car is totally stock with standard ignition
 
You have to find the right wiring diagram to start with. It is kind of weird. usually three wires total.
 
That shade of blue on both wires looks factory. Hard to find that shade, if a blue wire was added it would be "obvious " I would think. Black is black, so easy to match lol. Hope that makes sense?
 
Tell you what I had a hell of a time on my 74 making a new harness, mine was a late production and the aspen diagram was right.
 
Definately I would do some more research. Then verify it is the right ohm ballast resistor. The FSM should have the value listed in section 8
 
The car has never been restored, and I sincerely think that the engine compartiment wiring is original and unmodified :

Faisceau.jpg
 
You guys are sooo close.
The brown 14 ga wires are easy. J3 is power when the key is in start. J3A connects to the coil.
The second dark blue wire is almost certainly for the alternator field and regulator.
It's probably simply the difference between production and the engineering drawings. Concept is the same but execution is different.

One of those is probably J2 (power when the key is in run)
The other J2? either connects to the voltage regulator I terminal, or a splice junction, or an alternator field terminal.
The second two are only possibilities if the car was equiped with the ground controlling electronic voltage regulator. My understanding was that was introduced across all models/options in 1970. But I don't know how things were done with cars sent overseas for Simca.
 
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^^THIS^^ OP--wander over to MyMopar and download yourself the closest thing to the correct service manual, free. You may have to settle for Dodge vs Plymouth, etc.

The blues are the "ignition run" line, and the ballast is being used as a branch/ junction point.

Dark blue is what I call "ignition run" (IGN1 or J2) and is hot ONLY with the key in the run position. It goes dead with the key in "start." These blue are the ONLY switched 12V supply available under the hood, and depending on the year feed a number of things. This line is NOT fused!! Generally, feeds the ballast on the road to the coil, the alternator field 70/ later, IGN power to the VR, smog devices depending on year, and electric choke if used

The brown, IGN2 or J3 is similar to the yellow "start" wire and comes from the key. It is hot ONLY in start but is a separate switch contact. It feeds "full battery" power to the coil when in "start."

So far as the correct ballast, if it is not failing coils and runs well, I'd assume "correct." You can look up coil specs in the section 8 of the manual, as well as resistance values.

As others have mentioned, vehicle equipment "varies" with the country. For example, many / all? of the Mopars we've seen here from S America/ Mexico seem to have alternative charging systems, Bosch, Motorola, etc, rather than U.S. equipped Mopar alternators. 71 and later were "transistion years" for electronic ignition, and I guess was optional.
 
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Best I can tell, through '68 the blue and blue striped wires were the ignition (run) circuit.

upload_2020-12-23_9-46-52.png


In 1969 everything works as before but the junctions were changed.
J2 went to the voltage regulator first.
upload_2020-12-23_10-4-36.png


With the introduction of the isolated field charging system in 1970, also seems to be the begining of some changes in the naming and coloring convention of the wiring.
upload_2020-12-23_10-8-41.png


We can see in the '71 Diagram that the coil connection was supposed to be brown and is named J3A. This naming reflects the reflects the physical wiring connection; where as the earlier naming reflected the operational connection. With the previous naming convention, during normal operation power flows in the J2 circuit, all colored blue.

upload_2020-12-23_10-21-23.png
 
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Mattax said:
But I don't know how things were done with cars sent overseas for Simca.
Click to expand...

Simca was a french importer/dealer for Chrysler products
This Demon has never seen a Simca dealer.
It has been imported in Belgium through the Chrysler International S.A. sales network, not in France.
 
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