I need confirmation on the Tech Wiki section regarding the alternator conversion from external to internal voltage regulator.
I have a 19171 B110 (1200 coupe) with the old style 35 amp alternator with the external regulator that is causing way too many voltage spikes that affects my EFI injection pulse widths. The attached wiring diagram was taken from the Tech Wiki section and shows the wiring conversion for the B110 (smaller portion of the wiring diagram on the left hand side of the attachment.
The smaller diagram shows a red dashed line coming off the "S" lead off the alternator with a note "factory B110 harness". Is that referring to the factory "T" 2 wire harness or does this wire connect to another wire inside the 6-wire engine regulator harness?
I really don't want to risk burning up my electrical system by making a wrong assumption.
BTW, I will be using a 50 amp alternator, AC Delco PN 334-1578.

Cheers
Roger

Attach file:

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  B110 Alternator Conversion to IR.jpg (133.94 KB)

From what I remember since this was done years ago on my car.
Isolated pin on alternator with 10mm nut should be an #8 gauge wire to battery. Small pin on alternator with 8mm nut (I think) is ground. 2 pin plug should have white-red wire which should go to the idiot dashboard light. Last one, which is either white or red is connect to 12v which will give you a reading on a voltage gauge if you have one.

You should be able to just unplug the external voltage regulator and leave it or remove it. Rap up the plug with electrical tape or work your way into the wire bundle and remove it.
Easy.

I have a white/black wire on the stem part of the "T" 2 pin plug on the back of the alternator and a yellow wire on the "T" part of the plug. The white/black is probably the "F" alternator terminal with the yellow connected to the "N" terminal.
So, from what you're saying is that I should not have to jump any wires on the 6-pin wiring harness at the external regulator.

If you remove the voltage regulator, the alternator will not charge. If you replace the original Hitachi alternator with a newer internally-regulated Hitachi -- it still will not charge

* The T-connector is connected to power by the regulator. Once you remove the regulator, no power will go to the T-connector unless you jumper-wire the connector or jumper the alternator directly
* The T-connector wires are reversed for the two types

A Delco alternator doesn't usually use a T-connector unless it is a rebuilt Hitachi-type alternator (rebuilt by Delco)

vIs this the alternator you will be using?
Quote:Notice the Hitachi symbol on the back

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  AcDelco 334-1578 Alternator.jpg (163.98 KB)

The ACDelco is a rebuilt Hitachi that is specific to the Nissan 210/310.
I found this wiring diagram that appears to exactly match my existing external regulator alternator wiring setup.
This diagram doesn't show the reversing of the wires on the T-connector, but probably achieves the same results by using two jumper wires on the female end of the 6 blade harness connector.

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  6alternator_ir.jpg (115.30 KB)

As far as I know, no one actually reverses the wires. Instead they connect the T-connector wires to the appropriate harness wires. The easiest way to do it is to jump the Regulator Connector that is part of the Datsun 1200 wiring harness (this Connector is already wired to the T-connector that is the Y wire and WB wire). That's what your Datsun 510 diagram is showing -- 1970-1972 510 uses the same alternator wiring as 1200

Other ways to do this includes running new wires, or cutting and splicing the harness. But easiest just to jump the wires as shown in the Tech Wiki and also shown in the 510 diagram

1. disconnect the voltage regulator
2. in the regulator connector of the engine harness, connect WB wire to WR wire
3. connect W wire to Y wire

Photo showing one jumper wire in place

This is perfect. It confirms the required wiring for my setup. i don't need any sparks under my hood.
In your opinion, does the internal regulator alternator provide better voltage control than the old stock external regulator units? I just hate getting 16 to 20v random spikes on my EFI setup as it seriously affects the injector pulse widths and corresponding AFR fluctuations.

Thanks for helping out, it's been very much appreciated.
Long live the Datsuns and their owners.
Cheers

If you want to jump wires on the external voltage connection plug, that's fine. You're just patching your modification. Why not just wire the internal alternator direct. My external voltage regulator and plug has been gone for years. My alternator charges fine. Pull your wire harness apart, fined your connection points and make them. Simple. It will charge.

Agreed, it is more elegant and will be more trouble-free if you splice the wires and solder the connections. It's not as easy as jumper wires, but it's better. You can even run the correct size wire for 50A from the alternator to the battery (the existing large wire is designed for 35A)

Yes, the solid-state internal regulator (transistorized) has much better voltage control than the old electro-mechanical Regulator