External coil resistor question

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Troub

67 Dart 270, 225 slant six
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so after spending the day trying to figure out why the 67 doesn’t want to start anymore I decided to remove the coil as it has been in the path of an obvious long term oil leak. In removing the external resistor wire broke off. I assume this resistor is needed but see no replacements when I web search, just keep getting hits on ballast resistors. Pic of the resistor minus it’s broken wire attached...

941D2750-5650-44C7-A160-992A93A33C46.jpeg
 
The resistor was mounted to the coil bracket on the lower left. you can see the top of it under the grouping of wires. The wire broke inside the resistor so it doesn’t look repairable.

01D0CAE9-DA23-4605-A709-36F967BB96EF.jpeg
 
Everything I have read indicates that the Radio Coil Resistor is not required for the car to run. It does take the voltage spikes out of the signal coming from the Ballast resistor. I removed mine while changing the intake, same as yours the wire broke so I didnt reinstall it. When I fired up the teen for cam break in it ran fine for a week, then proceeded to trash the points and condenser. So, I took the resistor and dug out around the wire nub and soldiered the wire back on then tested it with an ohm meter. It's been running great for a month now without issues. Good luck trying to find a replacement for less than a small fortune.
 
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Everything I have read indicates that the Radio Coil Resistor is not required for the car to run. It does take the voltage spikes out of the signal coming from the Ballast resistor. I removed mine while changing the intake, same as yours the wire broke so I didnt reinstall it. When I fired up the teen for cam break in it ran fine for a week, then proceeded to trash the points and condenser. So, I took the resistor and dug out around the wire nub and soldiered the wire back on then tested it with an ohm meter. It's been running great for a month now without issues. Good luck trying to find a replacement for less than a small fortune.
Thank you gentlemen. I wish I would break things that are easy to replace. ☹️
 
TO TROUBLESHOOT THIS

Start by "rigging" something to form a test spark gap or buy one. "Rig" this to the coil tower using solid core wire, not the resistor spark plug wire probably used. If the wire to the test gap is kept away from other metal, it can even be a bare or low voltage wire. Crank the engine USING THE KEY that is do not jumper the starter relay. The coil should generate a nice hot blue spark, at least 3/8" long and likely longer

If not, measure coil + voltage with the key in the "run" position. If it is about 8--10V it is OK for now. If it is "same as battery" the points are open. "Bump" the engine until the points close and recheck

Check starting voltage, again at coil + while cranking the engine using the key. Voltage should be very close to "same as battery." Now measure directly at battery while cranking to get that reference figure. Both voltage readings should be at least 10.5V or more

Maybe the points are burned and have high resistance. Turn the key to run, measure coil NEG voltage. should not be more than 1 volt at most. If it is "same as battery" the points are open, bump the engine

The remaining possibilities, if the above all checks out, is coil going bad or bad distributor capacitor (condenser)

Also check the distributor shaft for excessive wear, general condition of points, rubbing block, a tiny bit of points/ cam lube

It also might be that the points are not getting a good ground. This is especially troublesome on dual point distributors, because the advance plate rides on a bearing, and there must be a small flexible ground braid, which can break or come loose.

There is no good way to check either a capacitor (condenser) or coil without special equipment. If the points and voltage checks out, replace the cap because it is cheap. If that doesn't cure it try a coil. It does not hurt to have a spare coil, in any case.

I'm going TO REPEAT one of the first steps. DO NOT use the coil wire to check spark, as they are usually resistive and can lead you down the wrong road.
 
Just for the sake of it...

The condenser inside the dist protects the points. The condenser (filter) on the coil reduces radio (RF) interference. (i think there is one on the back of my OE radio and I have seen some years where there is one on the back of the dash)

This web site has some capacitance values for ignition condenser and for coil RF filter (.22-.29uf)
HOW TO TEST A CONDENSER

This universal condenser shows .33uF
https://www.rockauto.com/en/moreinfo.php?pk=3979014&jsn=396&jsn=396

Like in post #7 the noise filter is not required. I never saw one on any of the 60's fords I have had.
 
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