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Discussion Starter #1
I just bought the car and installed a new starter. When I removed the old starter, there were 2 wires crimped together that were bolted to the "S" terminal on the solenoid and no wires were connected to the "R". The + battery cable on the big terminal was connected to where it should be. The car turns over now with remote starter but I cannot get any voltage out of the coil. The twin wires that have power when I turn the key to the on position are on the + side of coil and I attached the distributor wire to the - side of the coil. I get no spark coming from the coil wire from center of the distributor cap. Here is my question. Can I run a jumper wire from the + battery terminal and connect it to the + coil and will this get me the spark I need to see if I can start this car? It hasn't been started in 20+ years. I've already prepped the engine and I just want to see if this engine will fire up before winter.
 

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it should not be too difficult to remove the ign sw and test it. and the ign sw connector (wiring harness) Jump BAT to SOL and it should crank (won't run) if not this is one thing to repair. It just might be too corroded for everything to get the electrons where they need to go. could also swap coils. assume you checked the points, rotor, cap.
 
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1971 GTO resto mod. Modified 428 HO, 4 sp (built by midwest muncie) Dana 60, 3.55 rear
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Greetings,
The S on the solenoid stands for START which is what the purple wire is for...it activates the solenoid when you turn the ignition switch to the start position. The R terminal stands for RUN and what the yellow wire does is send 12V to the coil for start up because as soon as you release the key in the ignition switch, that circuit shuts off and the coil is fed through the resistor from the ignition switch. If both wires are crimped together and on the "start" connector, then no voltage gets to the coil as that comes from the "Run" terminal after the ignition switch is released from start to run.
Now having said all of that, your coil provides spark when the electric field collapses due to the movement of the points in your distributor. If the point gap is too close then the points don't separate enough to collapse the electric field in the coil and hense, no spark. It might also be just a bad coil. The Ohm value between the primary terminals should be less than 1 ohm. and ohm value between the ignition wire terminal and either of the primaries should be in the thousands of ohms.
Hope some of this helps.
Jim K.
 

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Discussion Starter #4
Greetings,
The S on the solenoid stands for START which is what the purple wire is for...it activates the solenoid when you turn the ignition switch to the start position. The R terminal stands for RUN and what the yellow wire does is send 12V to the coil for start up because as soon as you release the key in the ignition switch, that circuit shuts off and the coil is fed through the resistor from the ignition switch. If both wires are crimped together and on the "start" connector, then no voltage gets to the coil as that comes from the "Run" terminal after the ignition switch is released from start to run.
Now having said all of that, your coil provides spark when the electric field collapses due to the movement of the points in your distributor. If the point gap is too close then the points don't separate enough to collapse the electric field in the coil and hense, no spark. It might also be just a bad coil. The Ohm value between the primary terminals should be less than 1 ohm. and ohm value between the ignition wire terminal and either of the primaries should be in the thousands of ohms.
Hope some of this helps.
Jim K.
Jim, Thank you for the information. I needed that. My 66 Lemans was a factory 6 cylinder and now has a 455 installed. The starter/ignition wiring is hinkey. Not sure why they crimped those 2 wires together on the solenoid. I don't see how it would even start like that, but that's how it is. Also, the car has 2 coils behind the carb. The original (in its factory bracket) wasn't connected. A second chrome coil was just sitting on top of motor loose, wired up. It's pretty bad. I'm gonna bypass the old distributor and coil by installing a HEI distributor (single wire) and I may need to rewire the starter. Previous owner had some sort of alarm + ignition disabling device and it's a mess. As soon as I get spark, I know this engine is gonna fire up. Can't wait to hear that 455 thru that dual exhaust.
 

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Discussion Starter #5
Jim, Thank you for the information. Very helpful. My 66 Lemans was a factory 6 cylinder and now has a 455 installed. The starter/ignition wiring is hinkey. Not sure why they crimped those 2 wires together on the solenoid. I don't see how it would even start like that, but that's how it is. Also, the car has 2 coils behind the carb. The original (in its factory bracket) wasn't connected. A second chrome coil was just sitting on top of motor loose, wired up. It's pretty bad. I'm gonna bypass the old distributor and coil by installing a HEI distributor (single wire) and I may need to rewire the starter. Previous owner had some sort of alarm + ignition disabling device and it's a mess. As soon as I get spark, I know this engine is gonna fire up. Can't wait to hear that 455 thru that dual exhaust.
 

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If you are converting to HEI or other high-energy ignition, you need to do a little rewiring. Points ignition has two wires from the ignition switch to the coil. The wire from the “start“ position is regular wire, and delivers a full 12v to the coil for starting. The wire from the run position is a resistance wire (from the plug at the firewall to the coil) that provides about 8v while the car is running. HEI needs a full 12v while running.

You can either replace the resistance wire with regular wire, or use the resistance wire to drive a relay that is powered directly from the battery.
 

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Discussion Starter #7
If you are converting to HEI or other high-energy ignition, you need to do a little rewiring. Points ignition has two wires from the ignition switch to the coil. The wire from the “start“ position is regular wire, and delivers a full 12v to the coil for starting. The wire from the run position is a resistance wire (from the plug at the firewall to the coil) that provides about 8v while the car is running. HEI needs a full 12v while running.

You can either replace the resistance wire with regular wire, or use the resistance wire to drive a relay that is powered directly from the battery.
Thanks. I was wondering about that. I saw the two different wires attached to the + side of the coil. One was a regular insulated wire, the other had cloth or fabric around it. I'll make sure and run a wire that carries full 12v to the HEI when I turn the key on.
 
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