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Looks like points to me...But it's been over 30 years since I worked on anything with a set of points. Cap, rotor button and points are new, installed by the previous owner. They seem to be in great condition. I don't think this wire has anything to do with my problem of dieing at a stop light....That story can be read here...
Remember that there are two power sources for the coil. A "full" 12 v source for when the engine is cranking (reduced somewhat by the load from the starter), and a resistor wire that reduces the coil supply voltage to about 10.5 volts. This reduced voltage is what the coil is designed to operate at when the engine is running. Supplying 12v to the coil continuously will over heat the coil and burn the points. It appears that only one wire is connected to the coil. Test the voltage on the + terminal of the coil with the motor running-it should be less than 11v. Also test the red wire with the ignition switch in the "start" and "run" position.
I agree with JNB. If a car has points and a ballast resitor is not utilized in one form or abother the car will run well for about 50-100 miles at which point the points can burn and the car will quit running. Ask me how I know..
Remember that there are two power sources for the coil. A "full" 12 v source for when the engine is cranking (reduced somewhat by the load from the starter), and a resistor wire that reduces the coil supply voltage to about 10.5 volts. This reduced voltage is what the coil is designed to operate at when the engine is running. Supplying 12v to the coil continuously will over heat the coil and burn the points. It appears that only one wire is connected to the coil. Test the voltage on the + terminal of the coil with the motor running-it should be less than 11v. Also test the red wire with the ignition switch in the "start" and "run" position.
The purpose of the ballast wire is to limit the circuit current to 4.4ampers.
Voltage has nothing to do with it.
Not trying to be an azz, just trying to clarify how it works.
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Originally Posted by Big2Bird
The purpose of the ballast wire is to limit the circuit current to 4.4ampers.
Voltage has nothing to do with it.
Not trying to be an azz, just trying to clarify how it works.
(If only someone would write up a sticky explaining all this stuff.)
Is it safe to say that the black wire (as pictured above) has to be wired to be hot with the switch in the run position and not just when the switch is in the crank position.....Otherwise the car would start but then just go dead....?
The red wire that is not hooked up is made of 8 or so strands of very stiff wire, silver in color. It had a cloth covering most of which is gone but can be seen where enters the rest of the harness, I'm pretty sure it's the wire that is supposed to be hot when the key is in the run position.
So it looks like I have wiring issues to figure out....The battery isn't hooked up so I didn't get a chance to check if the red wire has any power at all.
Brian
OK looks like I need to go read the sticky....I did read an old post between Roger and 69427 about these issues....But it was over my head.
Is it safe to say that the black wire (as pictured above) has to be wired to be hot with the switch in the run position and not just when the switch is in the crank position.....Otherwise the car would start but then just go dead....?
The red wire that is not hooked up is made of 8 or so strands of very stiff wire, silver in color. It had a cloth covering most of which is gone but can be seen where enters the rest of the harness, I'm pretty sure it's the wire that is supposed to be hot when the key is in the run position.
So it looks like I have wiring issues to figure out....The battery isn't hooked up so I didn't get a chance to check if the red wire has any power at all.
Brian
Nothing is safe to say without testing.(You just don't know what someone else has done).
One wire "should" go to the R terminal of the starter. It gives full voltage/current while cranking only.
Another wire "should" be keyed on while in run, and should have a resistance wire in series with it to limit the ignition primary current.
If you have a VOM and know how to use it, now is the time to check.
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Originally Posted by Wee
Is it safe to say that the black wire (as pictured above) has to be wired to be hot with the switch in the run position and not just when the switch is in the crank position.....Otherwise the car would start but then just go dead....?
The red wire that is not hooked up is made of 8 or so strands of very stiff wire, silver in color. It had a cloth covering most of which is gone but can be seen where enters the rest of the harness, I'm pretty sure it's the wire that is supposed to be hot when the key is in the run position.
So it looks like I have wiring issues to figure out....The battery isn't hooked up so I didn't get a chance to check if the red wire has any power at all.
Brian
OK looks like I need to go read the sticky....I did read an old post between Roger and 69427 about these issues....But it was over my head.
Once the summer activities slow down a bit more I'm planning on writing up a one page summary of the sticky, and then people can read through the rest of the pages if they're interested in greater detail.
I miss Roger's contributions to the forum. He has a lot of experience and good information that he shared with us.
The resistor (ballast or wire) causes a voltage drop. This limits the voltage drop (available voltage ) across the coil. The sum of all voltages in a circuit must equal the supply voltage. The engineers that designed this system knew the resistance and inductance(that's the purpose of the capacitor-it "balances" the counter EMF of the coil and allows faster saturation) of the coil, and chose an external load(resistor) that would limit the voltage drop (and indirectly, following Ohm's Law) the current through the coil. The external resistor can only cause a voltage drop. Voltage and current are tied together, but the purpose of a resistor is to cause a voltage drop, not limit current. Designing a DC circuit while trying to use resistors to "limit" current will never succeed.
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Originally Posted by jnb5101
The resistor (ballast or wire) causes a voltage drop. This limits the voltage drop (available voltage ) across the coil. The sum of all voltages in a circuit must equal the supply voltage. The engineers that designed this system knew the resistance and inductance(that's the purpose of the capacitor-it "balances" the counter EMF of the coil and allows faster saturation) of the coil, and chose an external load(resistor) that would limit the voltage drop (and indirectly, following Ohm's Law) the current through the coil. The external resistor can only cause a voltage drop. Voltage and current are tied together, but the purpose of a resistor is to cause a voltage drop, not limit current. Designing a DC circuit while trying to use resistors to "limit" current will never succeed.
What test/reading am I looking for from the red wire if it is in fact the resistor wire that is supposed to provide running power to the coil.....? Switch off no volts.....Switch in the run position with the motor not running somewhere around 9 volts....?
I know if the black wire has power other than while cranking it is not correct....I don't see anyway it could be correct because the car runs as it is hooked up now.
I looked at the points last night and they don't look burnt to me....I have put around 150 miles on the car over the past 4 months.
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The resistor wire limits current not voltage.
Originally Posted by Wee
What test/reading am I looking for from the red wire if it is in fact the resistor wire that is supposed to provide running power to the coil.....? Switch off no volts.....Switch in the run position with the motor not running somewhere around 9 volts....?
I know if the black wire has power other than while cranking it is not correct....I don't see anyway it could be correct because the car runs as it is hooked up now.
I looked at the points last night and they don't look burnt to me....I have put around 150 miles on the car over the past 4 months.
Brian
On this schematic it shows a YELLOW wire between the + terminal of the coil and the "R" terminal on the starter solenoid.
The "R" terminal is the small terminal on the solenoid closest to the fender.
Peel back the black tape and see if your RED wire has a splice or check for continuity from one end to the other.
On the schematic your BLACK wire is shown as BLACK-PINK.
That wire will have 12 volts (battery Voltage) in both START and RUN.
I was testing last night trying to figure out where the black wire that is now connected at the coil + side ran to....Hooked up the multimeter set to continuity/beep mode took the wire off the coil and clipped one end of the meter to it then started to try wires on the starter but I didn't even make it that far...No matter where I touched it indicated continuity, this is with the negative cable disconnected from the battery. That doesn't seem right to me.
Thank Ya'll for the post above, I'll do more testing tonight.
