'72, questions on two engine wires
Thread Starter
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From: Camp Verde AZ
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'72, questions on two engine wires
A/C car, automatic.
The paired wires that connect to the + side of the coil, the red wire has some sort of braided shield or something around it, but the black wire is missing about 2" of insulation down from the U/spade clip, and the wire is stiff and silver colored, not normal stranded copper.
What is up with the missing insulation? Doesn't look right to me.
Over by the AC compressor, i have a black wire with a black round conical female connector that doesn't seem to go to anything, it comes from a plastic gang connector that is clipped to one of the AC hard lines behind the compressor. What is that wire for?
Thanks,
Doug
The paired wires that connect to the + side of the coil, the red wire has some sort of braided shield or something around it, but the black wire is missing about 2" of insulation down from the U/spade clip, and the wire is stiff and silver colored, not normal stranded copper.
What is up with the missing insulation? Doesn't look right to me.
Over by the AC compressor, i have a black wire with a black round conical female connector that doesn't seem to go to anything, it comes from a plastic gang connector that is clipped to one of the AC hard lines behind the compressor. What is that wire for?
Thanks,
Doug
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From: Crossville TN
That black wire is the resistance wire that replaced the [earlier design] ballast resistor in the ignition system. It runs to the fuse panel on the firewall and is the voltage feed to the coil when the engine is in RUN mode. The other wire comes from the "S" terminal on the starter solenoid and is the coil voltage feed during the engine START portion of the ignition cycle. The 'start' voltage is a full 12 vdc; the line for the 'run' wire is current-limited by the resistor to keep the coil from drawing too much current when higher rpm is experienced. Some folks think it is intended to lower the feed voltage. Actually, that voltage is just a resultant of the current-limited power on that line.
Thread Starter
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From: Camp Verde AZ
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2017 C1 of Year Finalist
Thanks, whats up with the 2" of missing insulation? Someone removed it for some reason? Looks like a short to ignition shielding waiting to happen.
I guess that explains the lack of a ballast resistor.
BTW, if you remember, i bought the car at a fair discount partially based on what i thought was a cam lobe going bad due a rocker arm that kept going out of adjustment.
After I pulled the suspect lifter,and found it and the cam lobe pristine, i looked at the pushrod,and one end was wearing off. A spare rocker and pushrod i had laying around fixed the problem.
I am finishing buttoning up my front half of engine/motor compartment resto now, repaint manifold, pretty up carb, new core in rad, detail engine compartment, semi gloss powder coat pulleys, fan and brackets.
So far the only numbers I have found that don't match are the starter (wrong date), and carb ('73 Blazer), everything else is correct and dated extremely close to build date (~less than 15 days), doesn't look like a bunch of 6 months or less ebay parts someone collected.
Doug
I guess that explains the lack of a ballast resistor.
BTW, if you remember, i bought the car at a fair discount partially based on what i thought was a cam lobe going bad due a rocker arm that kept going out of adjustment.
After I pulled the suspect lifter,and found it and the cam lobe pristine, i looked at the pushrod,and one end was wearing off. A spare rocker and pushrod i had laying around fixed the problem.
I am finishing buttoning up my front half of engine/motor compartment resto now, repaint manifold, pretty up carb, new core in rad, detail engine compartment, semi gloss powder coat pulleys, fan and brackets.
So far the only numbers I have found that don't match are the starter (wrong date), and carb ('73 Blazer), everything else is correct and dated extremely close to build date (~less than 15 days), doesn't look like a bunch of 6 months or less ebay parts someone collected.
Doug
Thread Starter
Race Director
Joined: Oct 2005
Posts: 12,470
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From: Camp Verde AZ
C1 of Year Finalist (performance mods) 2019
2017 C1 of Year Finalist
Any input on the orphan wire with the black conical connector? I found the parallel connector for the missing TCS, i know what that is for.
Thanks,
Doug
Thanks,
Doug
Thread Starter
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From: Camp Verde AZ
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From: Austin Tx
I agree with the previous posters about it being the super-heat cutoff switch, and the location of the switch.
I just wanted to add, that if you don't find a small post that the connector will fit on, the switch may have been replaced with a plug. So if that happens, don't assume that it's not the original compressor, a PO may have just removed the switch, and replaced it with a plug.
I just wanted to add, that if you don't find a small post that the connector will fit on, the switch may have been replaced with a plug. So if that happens, don't assume that it's not the original compressor, a PO may have just removed the switch, and replaced it with a plug.