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280zx Alternator Swap Into 75 280z

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Hey guys I had posted this over at Hybridz but wasn't getting much help. So here is my problem..


I have searched low and high to no avail. I am upgrading to a 280zx alternator in my 75 280. I was following the diagram below and carried out with the white to yellow but had noticed that my harness leading to the volage regulator did not have the specified green and red. It appears that the pin hole for the Green/Red wire was capped from the factory. So I am hoping that there are some guys here that have figured something out for the 75s that could help me finish this up? 


Thank you in advance...



Connect 1-5 
(lamp to windings common) green&red to white&black
Connect 2-3 
(+12V to Sense)                 white to yellow



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You do realize that you are using an internally regulated alternator on an externally regulated vehicle, correct?


To use the zx alternator with the built in regulator, the external regulator must be disconnected. Now two pairs of wires must be joined to connect 12 volts to the alternator at all times and to allow the red ignition or charge light to work in the dash. To do this I would trim the old external regulator plug leaving the wires from it  long. Bare and twist together the Black/White and the Green/Red and solder them and use heat shrink tubing or tape them up. Now bare and twist together the Yellow and the White wires and do the same. The other old wires you can remove from the old regulator plug so you have something like this...



Note that your charge light wire is Green/Red and mine was White/Red but otherwise the same and your plastic plug may be different shape (round?) or color






Now just plug this jumper back onto the harness plug where the external regulator used to be. This is what I did for both my 710s and it should work for your z car but it's up to you to verify this.




If it helps the...


Black is ground

Green is power from the ignition switch in the ON position

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Yeah I am trying to finish up getting rid of the old external voltage regulator. As my post states the 1975 280z does not have the green/red wire that should be used according to the write up on atlantic z. Therefore im not sure which wire to splice the black/white into, to connect the "L" connection of the new 280zx alternator. 

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My wiring diagram shows just what you posted with a Green /Red.

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I do nor know if it was planned that way, but the "L" terminal on an internally regulated alternator is for the Light.

When you turn the key on, 12 volts is applied to the charge light, and the charge light is grounded by the alternator.  When the engine starts, the alternator makes electricity, part of that is then applied to the charge light.  The light goes off, not because the ground was removes, but bewcause 12 volts is applied to both sides of the light.

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