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TR6 74' tr6 coil wiring

Wike

Senior Member
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I have been replacing various parts on my tr6, 74' over the last several months....water pump housing,radiator,battery, rebuilt distributor thanks to Jeff, plugs, wires and the COIL.
Being new at this, Can someone tell me the proper wiring for the Coil as far as..small wire from distibutor,wires from altenator, etc. Also,this has the external resistor.
Thanks all,
wike
 
Unless it's been altered, the pink/white wire is a solid core resisitor wire to the coil. It's conjoined with the white/yellow "starting wire".
Problem is distinguishing the color,especially the resistor wire because it usually has a woven sheath over the color coded insulation.
 
With an external resistor you should have a white wire from the ignition switch to one side of the resistor, the other side of the resistor goes to coil (+). There should be a white/yellow wire from the starter solenoid to the coil (+) terminal... or to the side of the resistor that goes to coil (+). From the coil (-) terminal there should be a wire (white/black?) going to the points in the distributor. If you have an electronic tachometer it would have its sense wire connected to the coil (-) terminal.
 
From dklawson:
"There should be a white/yellow wire from the starter solenoid to the coil (+) terminal..."
Maybe.. but on the 74, that wire comes from the Starter Relay.
I doubt if you can visually trace the entire route though because it is (or was) wrapped in harnesss tape and peels off from the rest of the wires in that section of the harness behind the alternator.
 
Thanks one and all. I will connect the W/Y wire to (+) side of coil, W/B from dst. points to (-) side of coil. That leaves me with a wire that looks to be red under the cloth sheathing that needs to go to the coil?.....and the external resistor wire goes to what side of coil? This ext. resistor was bolted to the engine block under the same bolt as the coil bracket and has just one wire.
Wike
 
If you have a "redish" wire left, look to see if there is a similar wire on your ignition switch. If so, dig out your multimeter and see if you have continuity from the switch end of that wire to the end that is in the engine bay. If you determine it is the same wire, measure its resistance. If it is a resistor wire it will measure somewhere between 1-2 Ohms end-to-end. As Poolboy said, some British car wiring harnesses used a pink resistor wire. When that wire is used, you do NOT use the external ballast resistor. The pink wire goes to coil (+) and the wire IS your ballast resistor.

You said the "resistor" was under the coil and "has just one wire". I assume this thing is "cylindrical" and metallic. If so, that is not a ballast resistor. It is probably a noise suppressor (capacitor). Others will have to tell you where and whether to hook that up. I'd start without it hooked up (just in case) because if it is internally shorted, it will complicate troubleshooting getting the engine started.

Poolboy, sorry for my over-simplification regarding the white/yellow wire connection. Regardless of end connection point, the function of the white/yellow wire is to provide full battery voltage to the coil during cranking, bypassing the ballast resistor (or resistor wire).
 
Wike said:
Tha This ext. resistor was bolted to the engine block under the same bolt as the coil bracket and has just one wire.
Wike
??? It's not an external resistor..It's a static supressor for the old AM radios...forget about it for now...
Both the Pink/ white (in the sheath) and the white/yellow were once conjoined and went to the same terminal.
If someone separated them, they would STILL go to the same terminal.
However, someone, a Previous Owner, may have converted to a non-ballasted ignition and now the coil is being fed 100% of the time by the 12 volt White /Yellow "starting wire". A lot of PO's did that.
Put the W/Y on the coil + and if the engine continues to run after the ignition key springs back to the "ON" position from the "Start" position, that's what someone did.
If the engine dies, then you need to put the Pink/ white (red cloth sheathed) wire on the + of the coil to keep the engine running with the key in the "ON" position.
I'm Not making this up. I owned a 74 and still visit it occassionally.
 
Visitation rights for ex owners :laugh:
 
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