1974 ignition resistor wire question
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1974 ignition resistor wire question
When a resistor wire goes bad, does it burn out to a "open condition"? or does it just loose all its resistance?
My '74 loves to eat points every year, (been doing this for years) my wiring system is all stock, (engine harness 25 years old, main harness 2 years old).
So I decided I would try to fix this
When I put the volt meter on the coil (+) and chassis ground, it reads 12 volts (key on) after it is started it reads over (13 volts). I just replace the ignition switch, the factory wiring has (2) leads on the positive side of the coils crimped into a single connector, one must come from the statrter solenoid and the other comes from the fuse block (resitor wire)
My '74 loves to eat points every year, (been doing this for years) my wiring system is all stock, (engine harness 25 years old, main harness 2 years old).
So I decided I would try to fix this
When I put the volt meter on the coil (+) and chassis ground, it reads 12 volts (key on) after it is started it reads over (13 volts). I just replace the ignition switch, the factory wiring has (2) leads on the positive side of the coils crimped into a single connector, one must come from the statrter solenoid and the other comes from the fuse block (resitor wire)
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Something is amiss. The ballast wire is resistive in its whole length, and impossible to short out into a low resistance line. It looks like a non-resistive line is feeding the coil (somewhere/somehow).
Edit: What's the C+ voltage when the points are definitely closed and the engine isn't running? (If your resistance wire is not present, make this a fast test.)
Edit: What's the C+ voltage when the points are definitely closed and the engine isn't running? (If your resistance wire is not present, make this a fast test.)
Thread Starter
Race Director
Joined: Jun 2020
Posts: 10,686
Likes: 2,251
From: north of Chicago
2025 C2 of the Year ('64-'66) Finalist - Unmodified
2025 C3 of the Year Finalist - Modified
2025 C4 of the Year Finalist - Modified
2024 C4 of the Year Finalist - Modified
2023 C2 of the Year Finalist - Unmodified
2023 C4 of the Year Finalist- Modified
2022 C4 of the Year Finalist - Modified
2022 C3 of the Year Finalist - Modified
2021 C7 of the Year Winner -- Modified
2020 C4 of the Year Finalist - Modified
Something is amiss. The ballast wire is resistive in its whole length, and impossible to short out into a low resistance line. It looks like a non-resistive line is feeding the coil (somewhere/somehow).
Edit: What's the C+ voltage when the points are definitely closed and the engine isn't running? (If your resistance wire is not present, make this a fast test.)
Edit: What's the C+ voltage when the points are definitely closed and the engine isn't running? (If your resistance wire is not present, make this a fast test.)
Also just bought a new starter solenoid to try (old one is 25 years old)
