Zed Head

Can you dig out 1 through 12, the originals with the pits? Looks like you stamped them. Just curious.

Also wondering about "self-locking" retaining rings. Doesn't 1975 use staked u-joints on the prop shaft? Non-serviceable. Are you breaking the rules?

I've had to use heat to get the yoke to expand enough to release the cap. People bend them often, I've read. I took my old 240Z shaft apart just to check it and regretted even starting it. Heat, a strong vise and lots of worrying. Nissan says that they should drop out with light tapping, after popping the snap ring off with a screw driver.

Here's the ID number info. I've never seen a "U" but Nissan says that signifies US or Canada. Don't know.

Don't you have to go through customs to get a car in to Canada from the States? Might be a clue. Any paperwork that you used to buy the car would be clues also. Didn't you get a title? What did you use to transfer title to your name? Any reason not to share the PO's name? Not much to work with besides the 957.

It's a "small bumper" car so more desirable. Too bad the back bumper has been replaced with wood. It's been bumped from behind. Is that old growth fir? Super easy to get running. Any L series engine and transmission should drop right in. Look around for the drive (propeller) shaft. Besides the engine, probably the only other drive train part of significant value. The radiator might be good to have also. Is pre-75 still emissions free in California? That's a bonus. But CA also has those "non-op" back fees. Are there fees to be paid before title transfer? I don't know the ID number system well but the FSM implies that it's not a US or Canada car. No "U". Don't know if the FSM is right or not. Which side is the steering wheel on?

Details needed. Start, no dice, not clear. Good luck. Here's the history -

The rust on the tip of the shaft doesn't look terrible. You can still see the smoothness underneath. Haven't seen anyone recommend removing the front cover. They're usually very stuck but it would make cleaning the splines much easier. Plus you can inspect the front two bearings and replace the seal.

Here's a trick that's in my brain, I don't know where it came from. Take a fan belt and place it around the damper pulley alone. Grip both sides of the belt in one hand, tightening it in the pulley groove. Use it as a handle to turn the crankshaft. You could also use one of those filter wrenches that uses a rubber belt to wrap around the object to be turned. Apparently called a "strap wrench". I've found that the damper bolt can be hard to reach sometimes.

The one that "looked good" looked more right. Did you rotate the distributor within its adjustment range, the slot on the lockdown screw, to see if the rotor points at 1? And don't overlook that it's the front of the rotor electrode that sparks not the middle. Imagine rotation in action. You'll find out when you set ignition timing. Might be fine, there is another adjustment on the distributor itself.

That's what I might do. I re-read my own comments above and couldn't figure out they'd guarantee distributor orientation. Sorry about that. Captain Obvious described using vise grips to hold the distributor shaft up then installing the oil pump. Seemed to work. Multiple paths to the same result.

https://www.rockauto.com/en/catalog/nissan,1978,280z,2.8l+l6,1209260,fuel+&+air,fuel+pump,6256 https://www.rockauto.com/en/moreinfo.php?pk=60014&cc=1209260&jsn=363

It's out there, hard to find. Rockauto has the specs I think. Your old pump is broken. It's not meeting its specifications. A new pump very likely will. Just trying to help. Go ahead and get one of those high volume pumps. You'll know when it's spinning, for sure.

You only need 30 gph. Excess volume will cause excess current draw. You'll be upgrading your alternator next. Good luck.

He also sells the Airtex pump. https://zcardepot.com/catalog/product/view/id/176/s/electric-fuel-pump-fuel-injection-280z-280zx-75-83.html/

Is it new? Pumps do go bad if they get crud in them, or rust up. I had a wrecking yard pump that seemed fine in the first few minutes but would slowly lose power and pressure as it ran. Even with the fuel cooling it the motor got hot and crapped out. It's still unclear how, exactly, you're testing the pump. Would love to see just a pump, some hose, an FPR, and a pair of pliers for pinching the return line. With a gauge reading of course. You're probably going to find that it was something simple once it's done. Carry on.

Seems much more than adequate. I don't know why they don't just put the specs out there somewhere. That pump is a replacement for Ford F350's with 445 CI diesel engines. Which means high volume of a more viscous fuel. The general spec for a stock L6 is about 30 gph at 36 psi. Higher volume means bigger draw on the electrical system. You don't want that on these cars, the electrical is on the weak side already. The Airtex E8312 is a common replacement. I have one, it's worked great for years and many miles. https://www.amazon.com/Airtex-E8312-Electric-Fuel-Pump/dp/B000DT7Y7K/ref=sr_1_1?ie=UTF8&qid=1540865716&sr=8-1&keywords=airtex+e8312 Here's the data for the 69136 - https://www.summitracing.com/parts/bch-69136/applications

Motorsport is good if you have the money and want someone else to do it for you. Or you can do the math and save a few dollars, plus learn "why" for the future, and be able to double-check Motorsports work. The bearings are all the same and are easily replaced in the sleeve. Here's that thread, with more links.

I see three "starts" here. Is the box on the bottom actually the startER? You don't have a the positive cable connected there, so it's not clear. Wouldn't be a surprise if your Start button cut power to the other switches. That's how the factories do it. Max power to the coil and starter.

Exactly. If you're not losing voltage at Start then you need to look at why the 123 wouldn't be making and breaking the coil circuit. The 123 needs power too, and a good ground. Your white wire test showed the that MSD works. The 123 just supplies the ground circuit. You never explained the other Start circle.

All of the transmissions are the same. The throwout bearing sleeve and the pressure plate need to match. Details were just posted in the recent "slave cylinder popping out" thread.

Is there voltage on the red wire to the 123 when cranking? Start. Break it down. Run and Start are two different things. Your MSD white wire test is a "Run" test, or "IG" in your case. You need to check Start.

So, does it always happen in the same way? Shift in to 4th, engine sputters and dies? Every time, only in 4th? Or is it RPM related? 260Z's have electronic ignition and they tend to fail after 40 some years. Good luck. More details = more ideas.

Here's the check to see if the MSD will work as wired. It replicates what the 123 should be doing. Providing a ground path for the white wire. If you do this test and get a spark then you can focus on the 123 as the problem. Break it down in to smaller problems.

I could be wrong. MSD says that the white wire is used for points so it might work with the 123 as you have it wired. Check your grounds. https://static.summitracing.com/global/images/instructions/MSD-6425_frm29772.pdf