Wiring identification

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May 12, 2013
Longwood, Florida
I have a question identifying the wiring in my 1987 FJ60.

I am in the middle of a V8 swap, getting my wiring issues figured out. I grabbed my FSM, and am working to find what to connect to what.

Starter is easy. Large wire on alternator also easy.

I am trying to figure out the Tachometer feed from the coil. I have a photo attached of the wires I pulled from the coil. The FSM diagram tells me the wire to the tach from the coil is


I have black with yellow stripe, (2), green connectors and one just black, with a blue connector. Which one feeds the tach? and yes, I need to solder in a variable resistor to adjust to the V8.

The coil also should have a hot feed when the ignition key is in both start and run. I think the FSM diagram tells me that this is the B-Y through a resistor, for run, and B-R, B-O for start. Which one of the three is this wire? I need a trigger for a relay to feed the HEI.

The two wires previously plugged into the alternator are white, and black with a blue or green stripe. The FSM tells me the wire to the charge light is B-Y coming out of the voltage regulator. It also has a Y-W wire thru a diode to a 7.5A fuse, or fusable link, (I am a Mechanical guy) The last wire is labeled W, which I am guessing is the sensor to the output, to feed back to the Voltage regulator?

If anyone can verify which wire does what, it would be a great help. Thank you

coil wires.jpg

alt wires.jpg
according to my 86 the tach wire is black wire with the big green male connector (the bottom one in your pic). the easiest way to figure out the rest is with a test light (couple bucks at the auto parts store you don't need anything fancy). hook one end to ground and probe the other two wires to see what one turns the light on when the ign switch is on. for the alt wires both will turn the light on with the key on but one will be dimmer than the other the dimmer one will also turn on the charge light. hope that makes sense.
found this its a pic of the plug for the alt I got from my alt shop. L is the light IG is the ignition.

you have two green connectors one male with black wire one female with black/yellow wire. the male connector is the larger one. that's the one you want. its the bottom connector in the first pic you posted.

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