distributor coil wiring problem
Thread Starter
Drifting
Joined: Mar 2011
Posts: 1,886
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distributor coil wiring problem
(Points type distributor. 1974 smallblock)
Having an issue with the coil wiring. When the starter is engaged, the coil is supposed to see 12 volts. When running, the resistor cable is supposed to reduce the voltage to something less than that. Man told me once, to about nine volts. Dunno if that's correct. Book says the resistor cable is supposed to be about 2 ohms. I measured 20 ohms, if I did it right.
I only see 6 volts at the coil all the time.
What's wrong?
Looking at the starter solonoid from the front of the car, there are three terminals. The terminal at 12 o'clock is the hot from the battery. There are terminals at 3 o'clock and 9 o'clock as well. What is the correct way to wire them up? I'm assuming one of them is the starting lead to the coil.
Where does the resistor wire come from?
Thanks in advance.
Having an issue with the coil wiring. When the starter is engaged, the coil is supposed to see 12 volts. When running, the resistor cable is supposed to reduce the voltage to something less than that. Man told me once, to about nine volts. Dunno if that's correct. Book says the resistor cable is supposed to be about 2 ohms. I measured 20 ohms, if I did it right.
I only see 6 volts at the coil all the time.
What's wrong?
Looking at the starter solonoid from the front of the car, there are three terminals. The terminal at 12 o'clock is the hot from the battery. There are terminals at 3 o'clock and 9 o'clock as well. What is the correct way to wire them up? I'm assuming one of them is the starting lead to the coil.
Where does the resistor wire come from?
Thanks in advance.
Last edited by gcusmano74; Aug 3, 2013 at 06:16 PM.
Le Mans Master
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The resistor wire comes from the ignition switch. The one from the starter (outside terminal- 9 o'clock) is the one that supplies 12v to the coil only when the starter is engaged.
Tech Contributor
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From: At my Bar drinking and wrenching in Lafayette Colorado
That's correct. The solenoid actually has the terminals marked: The "S" terminal is the wire from the ignition "Switch," which activates the starter. The "R" terminal bypasses the "Resistor" wire and provides 12 volts to the coil during cranking. you should have 2 wires on your coil "+" side: The one is the resistor wire, and the other one is the wire from the solenoid "R" terminal.
Lars
Lars
Team Owner
Joined: Jan 2006
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From: Crossville TN
That resistor wire just limits the amount of current that can be drawn by the coil...regardless of whether the engine is OFF or how high the engine is revved. That keeps from burning up the points (if you still have them). The voltage on that line might be anything...depending on whether the points are open or closed. DC voltage measurements on that resistor line are meaningless.
Thread Starter
Drifting
Joined: Mar 2011
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So the resistor wire is not in place to protect the coil, then?
Once I measured 6 volts at the coil positive terminal with the engine running. The next time I checked, after I had spent some time pulling on and trying to trace wires, it was more like 9 or 10 volts. What's up with that?
Once I measured 6 volts at the coil positive terminal with the engine running. The next time I checked, after I had spent some time pulling on and trying to trace wires, it was more like 9 or 10 volts. What's up with that?
Tech Contributor
Joined: Jun 2004
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
So the resistor wire is not in place to protect the coil, then?
Once I measured 6 volts at the coil positive terminal with the engine running. The next time I checked, after I had spent some time pulling on and trying to trace wires, it was more like 9 or 10 volts. What's up with that?
Once I measured 6 volts at the coil positive terminal with the engine running. The next time I checked, after I had spent some time pulling on and trying to trace wires, it was more like 9 or 10 volts. What's up with that?
