proper coil/distributor combination for '39

I just wanted to provide an update on the '39. I sent the distributor to Skip and he installed new points, rotor, rebuilt a coil and set up the distributor. While the distributor was out I removed all of the old wiring and may I say I'm surprised the car didn't burn to the ground. To say the wiring was bad is an understatement. Exposed wires, bad connections, cracks, multiple splices...it was bad. I installed a Rebel Wiring 6V harness and while running the wires I installed a few more ground points to make sure everything was grounded well. This weekend, after replacing the battery, the '39 fired up and ran beautifully. Skip's rebuilt distributor/coil worked flawlessly. I even loaded the family for 10 mile fun drive. This is the oldest car I've driven and it was a trip! I love it!

The only issues I have is the horn and dome light. Neither of them work.
- before the rewire, the horns would make a whimper. after the rewire, nothing. I think the problem is either the wire in the steering column or perhaps the connection in the headlight switch.
- as for the dome light, I'd really like to replace the wiring to them but I'm not sure how to that without messing up the headliner. Any ideas?

Thanks again for all of the help!
 
The horns are fed by a relay up front, and grounded through the wire in the steering column.

The dome light bulb may be burned out. If the wire was frayed and grounded out, it would fry the fuse. All lights are fed by the fuse.
 
Hey guys - obviously still learning.... What does the ballest resistor do and what is the symptom when it goes bad?
 
It reduces the voltage/current to the coil. If it is bad the voltage will be lower than required or non-existent. The early Ford coils were designed to operate in the 3.5-4.5 volt range.
 
adileo said:
Hey guys - obviously still learning.... What does the ballest resistor do and what is the symptom when it goes bad?
Click to expand...

The coil wants 4 volts. The ballast resistor is like a light bulb in that it is a small gauge wire that heats up, offering resistance to the 6 volts going through it at idle. When at higher RPM the charging system puts out 7 volts, the resistor gets even hotter, and still lets through only 4 volts. This explanation is simplistic, the actual voltages vary. When a ballast resistor goes bad, it does what a light bulb does.
 
Thanks Kahuna. What I didn't say is it also works to help keep coil voltage up when less is available, as while cranking the starter.
 
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