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Engine cranks, no spark

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poolboy said:
Randall, what if the - lead of the VOM were on the battery - terminal and the + of the VOM on the + of the coil terminal? Wouldn't that negate the position of the points ?
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Uh, no. The ballast resistor follows Ohm's law, meaning the voltage across it depends on the current through it. When the coil is not drawing current through the resistor, there is no voltage drop, and you would read full battery voltage. With the points closed, the coil draws current and the voltage drops.
 
I was under the impression that it was the ballast wire providing the resistance that caused the voltage to drop to what the coil required and provided that same voltage to the Pertronix.
 
poolboy said:
I was under the impression that it was the ballast wire providing the resistance that caused the voltage to drop to what the coil required and provided that same voltage to the Pertronix.
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As Randall said, there is no voltage drop across the ballast resistor (or resistor wire) unless current is flowing. With points (or ignition module) open you will measure battery voltage on either coil low-tension terminal. The points need to be closed to measure the "operating" voltage of the coil on the coil (+) terminal.

In a non-ballast (standard coil) installation you can connect the Pertronix red wire to coil (+) and have a good supply for the electronics. I know you said you've connected it this way on a ballast system and had no problems. However, I know of more people like Jay Barnhart who had problems when the red wire was connected as you suggest.
 
Upon further reflection and then inspection it seems likely my distributor is dead. Making a long story short, a replacement will be on the way shortly. Before I order it one more session will occur to make sure. I just want to get this step done so I can move on to the rest of the car.
 
dklawson said:
In a non-ballast (standard coil) installation you can connect the Pertronix red wire to coil (+) and have a good supply for the electronics. I know you said you've connected it this way on a ballast system and had no problems. However, I know of more people like Jay Barnhart who had problems when the red wire was connected as you suggest.
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Yeah, anyway I measure it, be it key "ON" or engine running, I get enough voltage for the Pertronix.
 
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