Captain Obvious

Looking at the pics, it appears that your 260 came with A/C. If that is correct, there's vacuum involved. That unconnected device is what Datsun called a "vacuum cokk", and it's purpose was to block all the water flowing through the heater core under some circumstances (like you had the A/C on). It's set-up dead-man switch style and is closed if there is no vacuum present. So yes... That could a reason you aren't getting any heat. There could be lots of other reasons as well, but I'd start with that one. Take a look at the 74 FSM (Factory Service Manual) in the Air-Conditioning section. It explains the function of that vacuum cokk. What is the current state of the system? Vacuum lines present and recently replaced? Vacuum lines present but old and leaky? Vacuum lines non-existent? No idea what I'm talking about at all?

Simple. Because: "All animals are equal, but some animals are more equal than others." - Animal Farm (1945) Not to be confused with "You fukked up. You trusted us." - Animal House (1978)

OK. Then I blame Jon as well. Works for me.

Thanks for the pics. I'm guessing that white thing was originally intended for home downspout connection. To convert from rectangular downspouts to circular drain piping? In any event, it looks like they repurposed that stuff and sealed with polyurethane expanding foam. "Functional is not how I would describe it. " Good luck with the reconstruction project. Looks like most of that is removable. Just a matter of getting your hands on the right parts.

@AK260, So a little bit ago, you suggested that the optimum crank position for peak pressure was 22 degrees ATDC, but the articles we've bantered around suggest that 14 degrees ATDC is optimum. Do you know the origin of your 22 degree suggestion?

Hey Ash, Is that smaller fan housing actually functional? If so, how is the air inlet connected to the firewall hole? Can you take a pic from a little farther back to show how it's situated?

"A bad day in the yard is better than a good day at work. My labor and risking life and limb in snake infested tall grass is free."

So? How about a close-up of one of yours next to a stock one?? And just think... In the beginning, it was a pipe dream and all sounded so difficult!

Counting his, mine, and granny's? About 40.

Awesome. When you said you were going to cut off the excess material on the lathe, I was going to suggest trepanning. I suspected that if you tried a traditional outside edge cut, there was no way you were going to be able to do that mounted on a mandrel like that. The interrupted cut would have made that impossible. Either the part would spin on the mandrel or the corners would have just bent over. Seems you're a step ahead of me! Looks great!

Cool. Just make sure you're careful if there's any fluorocarbon (for example... Viton) in there. Don't get it too hot.

Bummer. I had heard about one of those in my area, but never checked it out. Wonder if they're still in business or if they dried up.

Let me see what I have here first before you send parts. I know I have a complete working unit on my car, so I can take handle measurements off that (assuming they didn't change any over the years). What I'm not sure about is if I have a broken one laying around. I'll take a look when I get a chance. I did have one more thought on a repro technique... Make the whole thing out of metal, but make the handle section narrower than stock (and not tapered). Then glue on a hollow white plastic handle. Or a black one. Or a teak one. Or mother of pearl...

Agreed. I'm assuming weather and heat exposure are the two biggest contributors to the deterioration. Have you got one where it's broken, but you have all the parts still? You could sent it my way and I could poke around with it.

Yeah, I saw that. The quote I'm hearing from a lot of people "Shite just got real!"

Right. Her - "Hey, honey... The zombie apocalypse is coming. What should we do?" Me - "Well I don't know what you're gonna do, but I'm gonna stay home and work on my Z."

Can you post a pic of a working one and also post another pic of what yours does instead?

Absolutely. That would be an easy part for 3D printing. My only concern would be how durable would it be? I'm not sure how brittle that stuff is. My SWAG would be that the original part is glass reinforced nylon. So @jfa.series1, the original parts all snap off where the handle meets the spherical section, right? Another possibility would be to just make a "handle" and drill out a hole in the original sphere and glue a new handle in place? Tricky tooling setup, but might take less time than making a whole new piece from scratch. I still think that painting a metal one flat white would be the best all around solution. I'll just have to carry a magnet with me to shows in the future so I can tell originals from repros and judge the cars appropriately.

Nice. I did the same thing with the Dremel. Cut out the peened section enough that I was able to get the old nuts off without smearing any threads. The post-process lathe work was gilding the lily just to clean everything up and make it look all nice and purty.

I get you bro. !! And I agree with your assessment about the rising VE. And also agree that would be very difficult with springs and weights. Maybe I could whip up some little programmable device to try that. With the state of world events, I guess I have the time to work on projects at home...

Yes we do. That would be quite cool. And thanks for the info links as well. I dug into the one from ls1tech and it led me to another one on that same forum which led me to another good one. Here's what I found: https://ls1tech.com/forums/advanced-engineering-tech/254868-ignition-timing-101-a-4.html and the original article it was based on: http://www.contactmagazine.com/Issue54/EngineBasics.html

Someone with a properly tooled lathe could make this:

Perfect.

That's exactly what I did. I chucked up one of the old nuts in the lathe and turned off all the distorted threads and then used that nut as a "non-locking test nut" to make sure I could torque up the stub axle nice and tight without any binding. Then once I was convinced everything was OK, I took that nut off and replaced with the distorted thread version from the ZX and torqued it till my eyes bugged out. I'd post pics of the nut in the lathe, but I think it's pretty self explanatory.

Nice! I bet that works great on the thrust bearing cap. How easy does it work on the rear cap? Mine rear cap(s) took quite a bit of force to pull out.