SteveJ

How about posting a photo?

The video is finally ready to watch.

Here's an Amazon link: https://www.amazon.com/dp/B07ZMN2B59 You can find them on ebay, too. Just choose the 2 wire harness: https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313&_nkw=frontier+alternator+harness&_sacat=0

From the wiring diagram to show where I got the sensing voltage and the switched source: The black/white wire is below the voltage regulator in the engine bay. The white/red wire branches off the 10 AWG white/red wire that goes to the positive post on the alternator.

Covers are available from MSA: https://www.thezstore.com/page/TZS/PROD/12-4355. Make sure you create an account at MSA (http://www.zcarparts.com/) and enter your ClassicZCars member number to get a 10% discount on a lot of different parts. You can find your member number by going to your profile on this site. It's in the URL.

I haven't been happy with the charging system in the 260Z for a while. At startup, the alternator output was fine, but after a while of driving, the voltage would drop down to only 12.8VDC many times. It was time to explore options. Since I converted the carburetors into throttle bodies for the Patton Machine GM TBI fuel injection, I wasn't using the neutral (yellow) wire from the alternator for the fuel pump relay #1. That meant I didn't have the limitation a stock 260Z owner would have. (Of course, I could have worked around that one if needed.) Because I like experimenting on my projects, I decided to look into the Nissan Frontier 70A alternator. Since I didn't feel like paying ZCarDepot $150 for their setup, I searched RockAuto and found a new SKP for $86.79 (minus 5% discount and plus tax and shipping) alternator for a 1999-2004 Frontier 4 cylinder. On Amazon, I found the pigtail for the alternator $10.99 + tax. I took out the old voltage regulator (still a points style - Sorry, @Dave WM, I didn't try to adjust it first. It looked bad on the bottom to me.) and found the bottom side full of helicopter seeds and somewhat corroded. I tried some different bullet lugs to see if I could connect wires to the engine harness to run to the pigtail. That was a no-go. However, I found some alternatives. The white/red wire to the alternator positive had a smaller white/red wire with a female bullet to connect to a condenser on the old alternator. I would prefer to have a different sense wire, but it would work. Then I noticed that the condenser at the VR was connected to the black/white wire. There was my switched source. I would just need to make a small jumper harness to connect the pigtail and condenser to the black/white wire. For the most part it was a matter of removing the old alternator and installing the new one. I did have to replace the lug on the white/red wire because the positive post on the new alternator was much larger. That was no big deal, though it took some time to enlarge the hole on a 1/4" lug to make it fit on the M7 (or M8?) post. I shot some video that I need to edit that may help others with the swap. I'll see how it turned out and post a link. Here the Frontier alternator with the 260Z externally regulated alternator. Here's how the wiring looked when I was done with the installation. Here's the pigtail on the alternator going to the positive post for sensing voltage.

Yes, I tried two different "mama bear" door seals. That was due to the delivery times. They both pretty much seem the same to me. I don't have a preference between the two, but I haven't taken the car out, yet, to see how well they sealed. At least I'm not seeing gaps like with the 3/8" bulbs. The second link has choices for 30 or 40 feet. That can be handy. You just have to be patient for delivery.

Thanks for updating. It may help someone in the future with a similar problem.

I received the other "mama bear" door seal today and got it installed on the passenger side. It's a little different from the driver's side, but you'd have to look close to notice. Here's a link to it: https://www.amazon.com/dp/B00NELWRJ4 Now I have to drive the car to see if it is better than the Kia Sportage seals on the 260Z. (I think it is.)

If it's shorted, no voltage will pass. Since the gauges move on decreased resistance, they would be pegged if there was a short.

You can always just see if you have voltage to ground at the end of the wires in the engine bay and at the fuel tank. No voltage = no signal.

Of course, it wouldn't hurt to see if you're getting voltage at the dash to engine harness connector for the water temp and oil pressure and at the dash to body for the fuel gauge. See page BE-34 for the water temp & oil pressure wiring. See page BE-35 for the fuel gauge.

You could use potentiometers: https://www.amazon.com/TWTADE-Potentiometer-Single-Variable-Aluminum/dp/B07DHGHQPQ Then you would also see gauge response. Center tap to ground and signal on CW or CCW.

Ejection seat

I've spent WAY too much time on Amazon studying generic door seals for the 240Z. I even tried some with mixed results. The first one I tried had a "bulb" of 3/8 of an inch (9.5mm). It left gaps, allowing wind noise. I took a chance and went big on the next try with a 0.7 inch bulb (17.8mm). The door would not close properly. Okay, so I figured the "mama bear" size would be about 0.5 inch (12.7mm). I got it today and installed it. It had a nice snug fit around the doorway. The door takes a fair amount of effort to close, but it will close completely. There are no gaps that I can find around the door, either. Here's a link to this door seal on Amazon: https://www.amazon.com/dp/B097MPM512 20220220_164404.mp4 Now to get more for the passenger side. By the way, you'll need about 11 feet of material to go all of the way around the door.

Exactly. That's why I asked for pictures with the cover off and the wires.

It will be a while before I can compile a list for you. I have a car coming over today for me to work on. Meanwhile please take photos of the VR with the cover off. Try to frame some of the photos where I can see the internals and the wires coming down to the connector.

There shouldn't be any parts that fall out if the VR is in good condition. However, it might be better to document the pin arrangements (wire colors) on both the engine harness and VR first. Something might jump out to us. Basically it's like the alternator isn't receiving the field signal from the VR recently installed. I would have to dig into to the circuit again to postulate the causes. What I would really like to see prior to tearing into things are some voltage measurements at the battery prior to starting and at 2500 RPM.

I believe @HappyZ is intending upon running a Pertronix or some other electronic ignition that can be retro-fitted into a 240Z distributor. Yes, you can put the 240Z distributor on the L28. And as for heat rise, I fabricated my own heat shield for my setup with an L28 with a Maxima head. I also have square port headers on it that I've been running for 5 years. I don't know if the engine is losing low end power. It pulls well.

Don't trust the gauge in the dash for good diagnostics. Get a real voltmeter for that. The gauge is good for "Oh crap, there's a problem" kind of readings. You know for sure there were issues with the old voltage regulator, just from the potting material being cracked. That could have allowed corrosion on the underside of the circuit board. Pro tip: You can use a sewing pin or a T-pin (office supply stores) to back-probe a connector like on the voltage regulator to see if it has the right signals. Let me know if you get a hand-held voltmeter, and I can walk you though taking measurements.

So there are 3 control levers with 4 control cables. The top lever has two cables. One of the cables goes off to the right. It moves when moving the top lever between Off and Vent. The other cable goes off to the left and moves when moving the lever between Vent and Heat. The middle lever for the temperature control goes to the right and connects at the watercock at the heater core. The bottom lever goes over to the left and connects near the door that covers the footwell vent. It moves when you move the lever from Def to Heat. Here's a backside view of the control panel. Sorry I couldn't get a better photo. At least you can see a couple of the cables. Here is the fresh air (Off to Vent) connection. It's up near the firewall in back of the fan box and is probably obscured by the glove box. (I removed the glove box recently.) Here is the Vent to Heat actuator. It is on the drivers side above the hose that goes to the side vent. Here is the cable connection at the watercock. It is on the passenger side near where the heater hoses come through the fire wall. Finally, here is the cable connection for the Def to Heat lever. It is on the driver's side near the firewall where the door for the heated air vent is. Does this give you what you were looking for?

Dang it! That's another tool added to my Amazon wish list.

Yes, @Captain Obvious, the strut number is stamped on the housing toward the bottom.

This is why we need orange as a choice for paint. Also, I like the break in the grille.

That's what @240260280 taught me to do.