SteveJ

If your ammeter was non-functional, it would affect many systems in the car, including making where you had no power to the ignition. A jump start wouldn't solve the problem, either. For a 73 with the ZX alternator swap, you have to be careful that you don't have the electric fuel pump modification in your car. That modification added some wiring that includes providing power for the fuel pump relay coil. Leaving this wiring modification in place after swapping in the ZX alternator will cause the relay coil to be energized all of the time. That will run down your battery. Keep in mind that if your electrical system is good, you won't see the ammeter move hardly ever. The ammeter was moving with the turn signals before probably because the voltage at idle was low. The voltage dip from the lights lighting up meant that the battery had to prop up the electrical system momentarily. The ammeter measures the flow between the battery and the alternator. All but a couple of electrical components are wired to the alternator side of the ammeter. (I believe the brake lights and hazard lights are two exceptions. They will light up with a blown ammeter.)

When diodes go bad, it isn't pretty.

Mea culpa. I misread the wiring at the lamp. Based upon Zed Head's last post I looked again and realized my mistake. I thought the lamp had blue & black wires going to it. (That in itself confused me some because with the 260Z, blue was usually a wire that became grounded.) Instead, the lamp has blue & green wires going to it. That makes sense since green is usually a positive. I stand corrected, even though I'm sitting down right now. Now, I did a quick search, and I believe this link points me in the right direction. https://youronlinemechanic.com/alternator-with-neutral-point-voltage/ It says there is an AC component in the neutral voltage. You don't want to put a DC coil in an AC circuit...Er, I've heard that from a friend. If the AC component is high enough, it might smoke a regular DC coil. A diode in the circuit might help. This is all just speculating in this application. @Captain Obvious Maybe we should sneak over to my house during ZCON and hook my OScope up to the neutral and see what the waveform looks like.

I misread the drawing that Zed Head attached. I need to get more sleep. I looked at the 76 wiring drawing to fill in details. The neutral goes to a coil in the VR in the 76. When the potential on the neutral is higher than ground, the associated contact moves the blue wire (lamp) from in contact with ground to the white wire (12VDC+) and lights the charging lamp. (Unless I have something backwards from looking at drawings when I'm tired.) For the 74, the neutral goes to a coil in the VR and when the neutral has voltage with respect to ground, the associated contact grounds the black/yellow wire that goes to pin 12 on the Seatbelt Interlock unit. For the 240 wiring diagrams, the VR is shown as a black box, so I don't have a ready description of what all it does in that application, though I think I have a 240Z VR lurking around unused in my garage.

The neutral should be bonded to the ground. So it is at zero volts with respect to ground. If the neutral is not bonded, that can cause problems like a floating reference if the alternator is turning.

Yes, you do. Mountain Dew & Diet Dew are the only socially acceptable P-word company drinks. Otherwise enjoy the fine products of the Coca Cola family. True story - I used to travel up to Canada on business, but Diet Dew was not available in the Toronto area at the time. I would fly into Buffalo, rent my car, fill up on Diet Dew at the grocery store, and go across the border. If I ran low, sometimes co-workers smuggled more across the border. Civilization was slow getting to that land up North.

You weren't the only one thinking that. So much for not going off the rails.

By the way, Bruce, I believe I may still have a set of flat tops taking up some space in my garage...

Give it a try. Here's my latest selfie. Funny, the camera on my phone stopped working just after I took this photo.

Can you attach a better looking face to my name?

Go to Knoxville where there are a bunch of UT fans wearing an ugly shade of orange, or go to Atlanta a see a bunch of great Z cars. WHY do you suggest there is a decision?

Congratulations on the new job. I hope it's less travel than the old one. Just make sure you build a big enough garage for your Zs at the new homestead.

I guess the Jims will outnumber the Steves.

It's less than 2 hours from the host hotel. https://tinyurl.com/ycd56s74 Blairsville is about an hour from my house.

That isn't what my experience was. For the 73, the rear bumper was easier than the front. You can use the 73 rear bumper brackets on the early rear bumper with no modifications.

To elaborate on Zed Head's response on coil vs ignition module, the coil is an energy storage device/transformer. It can take 9 (ballast resistor present) or 14 (operating voltage when the alternator is turning) volts DC and step it up to 20,000 to 40,000 volts DC depending upon the number of windings in the coil. The lower voltage side of the coil is an open circuit. The negative post has no direct path to ground. This is where the ignition module comes in. The ignition module detects the position of the distributor, usually with an optical trigger or magnetic reluctor. At the appropriate time, the ignition module closes the path to ground for the coil. With the completed path to ground, you have current flow through the low voltage side of the coil and a spark at the spark plug.

Driving or flying?

Actually, the drive is to Helen back. ?

Well, it's just about 3 weeks until opening ceremonies for ZCON 2018. Who is in? By the way, the typical high temperatures for mid October are in the low to mid 70s. Lows are typically in the mid 50s to upper 40s. It will be great driving weather for those of us bringing S30s.

That is correct. I did NOT have to modify the 70-72 bumper brackets to fit an early bumper to my 73.

To be clear, you can use the 70-72 bumper mounting brackets on the 73. The mounting holes for the early brackets are there, and no modifications are needed. There are reproduction mounting brackets available such as from site sponsor @zcardepot.com https://zcardepot.com/front-bumper-bracket-stainless-steel-240z-1970-73.html

To put the early bumpers on my 73 I had to do the following: Buy a set of early bumpers. Buy a set of early bumper brackets. Remove the old bumper and bumper mounts I did a "dry fit" and determined I needed spacers on the sides. I installed the bumper. It's not too difficult, but my next door neighbor did lend a hand here and there. https://fiddlingwithzcars.wordpress.com/2014/01/20/installing-the-front-bumper/

I put my CZCC member number in my account profile at MSA. Any time I place an order online, all discounts are applied automatically. Just so James sees this thread and wants to add anything... @James@TheZStore

You can always tag Dave @Zs-ondabrainhere. I'll ping him on FB, too. Update: Dave responded to me on FB. He'll probably see this thread in a little while.

http://www.thezstore.com/page/TZS/PROD/10-1971