Zed Head

More block confusion. https://datsunzgarage.us/engine/

Here's the cutaway engine thread. Not sure it gets in to cooling areas, I have to watch the video again.

What type of engine block do you have, N42 or F54? There's quite a bit of discussion around the internet about "siamesed" cylinders. Apparently the early blocks were blocked off between cylinders and later blocks were open. Edit - this might be backward. See #22 below. In your second picture what you're showing as a blockage is really just the casting itself, I think. Steel. Poke a screwdriver in there. I haven't seen a cutaway of an L engine engine block but the way it should be is that the lower portion of the cooling passage would be open, that's where you'd get left to right flow (actually front to back but shared at the bottom), but the upper portion (where the core plugs are) would be isolated by cylinder so that coolant is forced to flow upward and in to the head. Like a manifold, with the open bottom "plenum" pressurized by the pump. A block cutaway would be interesting I think that there might be one on the site. Somebody cut an engine in half and made a three cylinder L engine. It's on the site somewhere. You should buy Monroe's How to Rebuild book. It's worth the money and time to read it. https://www.amazon.com/Rebuild-Your-Nissan-Datsun-Engine/dp/1931128030/ref=sr_1_1?dchild=1&keywords=How+to+Rebuild+Your+Nissan+%26+Datsun+OHC+Engine&qid=1607375412&s=digital-text&sr=1-1-catcorr

Here's a good web page with a video. He sprays water in from the top holes and you can see it coming out the core plug areas. Some long skinny brushes, a hose, and time will probably get you feeling confident. http://www.kangamotorsports.com/blog/datsun-engine-block-cleaning

Not sure the coolant is supposed to flow left to right. I'd pour water in the inlet at the pump area and see where it goes. Stand the block on end and run some water through the front cover inlet where everything starts. It should come out the holes that connect to the head. That's the path. Completely blocked coolant passages is not as common as people think, I think. You hear/read the stories about stop leak usage but most of what people find in their blocks is just stuff that dropped out in the dead flow areas. I've never seen a story from anyone who had overheating problems and found that clogged coolant passages in the block was the cause. A better radiator and a good water pump is usually the fix. The clogged passages stories are what people see and think must happen, "what is all this stuff in here" (no offense), but the coolant passages are really very crude. It's a big open cavity between the block walls and the cylinder bores. Most of the cooling happens at the top of the block and in the head. Anyway, I wouldn't overthink it if it was mine.

Hot tanking is no longer what it used to be. Nasty chemicals are being regulated. Do a search on it and you'll find stories about today's cleaning processes. You might do more damage trying to clean it than just doing the minimum needed. It's just going to get dirty again anyway. Kind of looks like old antifreeze residue. Whoever told you the block was "done" should not be listened to in the future. If the passages aren't blocked it will probably be fine.

Pretty sure the switch (not a sensor) is a straight thread, not a tapered pipe thread like the plugs, and it has proper flats for a wrench. 17 or 19 mm if I recall right. Should come right out, your biggest worry will be damaging the wires which will be rock hard after 40 years of baking. Heat will have a big effect. Those plugs have been bathed in transmission fluid on the other side for years and are steel in aluminum. If they've never been out then they still have Nissan's super sealant on the threads. Heat will loosen the sealant. Heat. Heat. Heat. When I was removing my diff fill plug I could only get it to turn after heat. As it cooled down it tightened up again.

I wonder if the door is complete. That would be worth some money.

Paint the factory coil red and put a Blaster sticker on it? Or just save the blaster for use with the 6AL. Thanks for coming back with the solution. Nice when a guess turns out right. It is odd, really, that the Blaster doesn't work. A condenser on the negative wire might get the Blaster working but, why bother?

Consider the source. Looks like just more distraction. Essential part of the shell game. https://www.nbcnews.com/politics/2020-election/trump-announces-rudy-giuliani-has-covid-n1250163

And, I don't think is your problem, if you do get it working with the Blaster coil, see below. https://www.summitracing.com/parts/msd-8202

One of the basic rules of torubleshooting a new problem is to go back and look whatever changes were made before the problem showed up. A coil swap is simple and will take that possibility out of the equation. As far as the coil goes, factory parts are almost always of better quality than aftermarket. MSD is not even owned by MSD anymore. It's a brand name, owned by Holley. And Holley was purchased by private equity back in 2012, after they went bankrupt a couple of times. Private equity firms are all about profit. Basically, MSD and Holley and most of the big auto names many of us grew up with are really just brand names now, parts are manufactured wherever the cheapest labor is. Sorry. Hate to be a downer... https://www.holley.com/brands/msd/ https://en.wikipedia.org/wiki/Holley_Performance_Products

Those wires, the red and green, actually went to the old distributor and the ignition module under the dash. They are the trigger wires. Not used anymore because all of that is contained in the ZX distributor now. If the engine starts and runs properly and the tach needle is twitching then odds are the connections are correct. The blue wire supplies both the ECU and the tach with the spark signal, to fire the injectors and run the tach. They're on the same wire. Might also be that your new coil is "noisy". Might be worthwhile to swap the old coil back in, just to see. The coil is the other thing that is different now.

https://www.atlanticz.ca/zclub/techtips/distributor/index.html

No, I'm talking about a new condenser that wasn't part of the original setup. Edit - actually your engine wouldn't run if the blue wire was not connected. So, ignore the words below. The blue wire needs to be connected to the coil negative terminal. That might explain both why the tach doesn't work and why the ignition system worked with the old module plugged in. Not really clear what you mean by "coil wires" though. What are you using to power the ZX distributor?

If you have a spare alternator condenser/capacitor around you could connect it to the coil negative post. I don't know exactly why (my logic is not of the professional sort) but it worked for me. Won't hurt anything.

Liverpool fans. If you follow soccer you know that the games are almost more about fans singing and shouting than actually watching the game. Probably the best place to catch the virus in an outdoor setting. Standing in one place surrounded by shouting singing men who don't realize that their nose is involved in breathing.

It's a bulge in that taped up wiring harness somewhere in or around your picture. Find the bulge, peel the tape back, it's an odd looking plastic thing with two bullet connectors, small than a quarter. Signs still point to the ZX E12-80/match box. Nothing bad about learning more about where all the parts are though. You've also confirmed that the ignition system will work even though the old ignition module is still plugged in. I've wondered about that in the past.

I think that you might have to ground the potentiometer (dash light dimmer) circuit to get the lights to work. It might ground through the dash frame. Gotta have a ground. Last thing - measure resistance through the circuit from power supply to ground before you apply power and you'll know if you have a dead short before you even blow any fuses.

Put one of these in the power supply line from the battery. A 20 amp fuse (or 10 if you want to be really cautious) should protect any of the wires in the harness. If it blows right away you have a short. As you turn on various lights and gizmos and it blows you'll have a clue about which device has a problem. The 240Z owners manuals have good wiring diagrams in them. https://www.autozone.com/electrical-and-lighting/fuse-and-accessories/bussmann-atc-fuse-holder-with-cover/32415_0_0?spps.s=4180&cmpid=LIA:US:EN:AD:NL:1000000:ELC:71700000060662503&gclid=CjwKCAiAn7L-BRBbEiwAl9UtkHW6xyqKPANG2FaYsa9znpvCznDnG5GjjBuOLa2uPpPq0ebehc1UzBoCzqQQAvD_BwE&gclsrc=aw.ds

I think this is actually faster. Definitely different.

It would need to be brazed back together after taking things apart. You might find an aftermarket solution. I did a quick internet look but didn't find anything. You definitely need to fix it though. Check your cam shaft carefully. If it's been that way for long then your cam lobes have not been getting lubrication. If your cam shaft is shot then you'll want to get an internally oiled camshaft to replace it.

Take off the valve cover and check the spray bar. I think that your guess is correct. Hopefully there are no damaged cam lobes. Also possible that it is left over from some past catastrophe up top.

Watching a soccer game in England. They decided to let fans attend under "strict" rules. Must wear a mask, must maintain distance, no singing or shouting. What could go wrong? https://www.france24.com/en/live-news/20201205-premier-league-tells-returning-fans-to-avoid-excessive-singing "Chelsea's game against Leeds at Stamford Bridge, which starts at 2000 GMT, will also have 2,000 fans present. The Premier League issued advice on safety measures on Saturday, including a warning for fans not to get carried away when their team scores a goal. "Fans can celebrate but should remain socially distanced from people outside their social bubble," said the advice. "Hugging of other fans and high-fives should be avoided and fans are asked to be respectful to those around them, including avoiding excessive shouting or singing." Look at all of the noses. I have a friend who calls that kind of mask a chin diaper.

If it has the indents I'd guess that they were smashed in there when the car was dragged through the field. And the front end might just be smashed and rusty 76 parts. JUST SAYING!! (Why am I even writing about this turd...)