NewZed

Good luck with wherever this is going. It's possible that the engine did spin, but if it did the chain tensioner has certainly popped out of its bore. You'll never get the head installed with the chain properly on the cam sprocket without pulling the front cover. Good luck. https://www.amazon.com/Rebuild-Your-Nissan-Datsun-Engine-ebook/dp/B006VUICHG

Look down the hole at the front of the block. There's probably a pile of chain down there. Might as well pull the engine, buy the "Rebuild" book, and save yourself a lot of trouble and money. Good luck.

Looks like you're not reading what people are writing. No offense. These aren't 60's era small block chevy engines. Overhead cam. You can't spin the engine with the head off, normally.

Your description doesn't make sense. You said it's apart. Then you said that you can rotate the engine (probably meant can't). Then you said that you did something that could only be done with the head off. If the head is off you can't rotate the engine unless the front cover and timing chain are also off. If you're trying to spin the engine in the car with the head off but front cover on then you might have jammed the timing chain in to the gears. How about a picture of the engine in the car? That will tell something.

You're welcome. I spent some time working on the opposite problem, the pump cutting off at low PRM when the engine was cold, and got familiar with the system. Don't mess around with the spring adjustment if you start thinking you need to adjust fuel-air ratios. There are better ways.

Yes, the contact in the AFM provides power to the fuel pump relay, which is right above the hood latch pull. The 78 engine would not affect the fuel pump control unless a 78 AFM was used that does not have the contact. Many 78 AFM's do have the contacts but they are not used in the 78 cars. But they will work in 76, I had one on mine. The black cover just pops off by hand, it might have a little sealant on it. It's the quickest way to see where you're at on the problem scale. Not uncommon for people to rewire things though. If there's a vacuum leak the AFM tends to run closer to closed and can cut fuel. People create new problems trying to solve others.

Take the black cover off of the side of the AFM and see if the fuel pump relay contact switch is opening when he AFM blade closes. That's what cuts power to the pump. It's shown in this link. You can bend the thick rod to adjust it. Move the counterweight and you'll see what is supposed to happen. http://www.atlanticz.ca/zclub/techtips/afm/index.html

Do you have a picture or a link to the bearing? Why would a manufacturer put teeth on a throwout bearing surface? Seems odd. https://www.rockauto.com/en/catalog/nissan,1994,300zx,3.0l+v6+turbocharged,1209787,transmission-manual,clutch+release+bearing,1968 https://www.rockauto.com/en/catalog/nissan,1976,280z,2.8l+l6,1209226,transmission-manual,clutch+release+bearing,1968

The car will roll and corner and brake and absorb bumps with the differential completely removed. This would require a hill or towing, of course. There is no functional connection between the differential and the wheel axles. You could install a Ford 9 inch or a long nose R200 or a short nose R200 or an R180 and it will have zero affect on the probability of a wheel falling off. The only connection between the wheel axles and the differential are the drive axles, aka half-shafts. There is no "mount" that would serve any purpose in connecting the differential and the wheel hubs. The cars have independent rear suspension. Thoughful_edit resurrected an old thread and made an absurd comment. Why are you trying to defend it? It makes no sense. The differential will have absolutely no affect on the probability of a wheel falling off and the car crashing in to a stone wall. Gibberish. The purpose of the forum is partly education in addition to entertainment. My original short comment was meant for education. I really did not expect such resistance to understanding how things work. As far as being "willfully obtuse", well-done on the grammar, but I think that you're projecting. It's actually a bit scary when somebody keeps repeating nonsense and seems to believe it.

Defend this calZ. Good luck. Here's a drawing to assist in the discussion. #1 is commonly known as the "diff". #6 is the wheel, or hub, axle. #7 is commonly called the half-shaft. It connects the diff axle shaft to the hub axle. Where the wheel mounts should be obvious. Let's see where this "mount" would be installed.

Explain how a shortnose diff affects a wheel falling off differently than a longnose diff. For your own edification.

The diff has nothing to do with a wheel falling off. If you think it does you're confused. No offense.

You're confusing hub axles with diff axles.

The last post was 6 1/2 years ago. Not clear who you're asking. The negative post of the coil is the one that is connected to the ECU.

Why don't you just reset the preload and see what happens first? The FSM says it's the same for new or used bearings.

I didn't watch the video. Sound rarely comes through well on the old internet from the phone recordings. If it's that bad I'd take up the shop's offer to open it up again. That's not normal. The whirring noise is. Seems like you're sampling other people's transmission noises so the picture is more clear to you now. Maybe go to the shop with somebody who has a good one so the shop knows what a good one sounds like. Good luck.

I think that what we're saying here is that they all do it. Another used one will to. And the 240SX 5 speed (AKA 71C) is essentially the same design as the 71B. Not sure but it probably does it too.

You can find quite a bit around the various Datsun forums about the noise from the transmission when in neutral with the clutch engaged. Might be that your 4th gear grind just made you hyper-aware. I had three different 5 speeds in my car at various times and they all had the noise that went awya when you pressed the clutch pedal. I have a memory of @JMortensen telling a story about a new rebuild having the noise. I found one.

Get a list of all of the bearings that they replaced. The adapter plate bearings are tough to do, they might have skipped those. Any notes on how far down they took it would help too. Since you told them to only replace what they thought was worn they might not have gone very far. More details on what happened after you forced it in to 4th might help. Did you drive it afterward? How did it get to the shop? Did the problem go away?

Can't remember but I think that it might actually be in Monroe's Rebuild book. But here is a writeup that a past member put together. The towers are bored for the cam after they are installed. When they are removed any mismatch on reassembly can cause cam binding. I've never done it myself I just remember reading about it. He doesn't mention the tapping, I must have seen that somewhere else. Basically, if rotation gets tight a couple of light taps on a tower or two can loosen it up. The goal is to get everything torqued and have a cam that rotates freely.

Somebody probably used the torque values in Monroe's Rebuild book. Apparently there's a typo in the book, the value is too high. Make sure you do the tap-and-rotate alignment when reassembling. Nissan considers the cam towers as non-removable.

Here's another wiring scheme but I think that it causes the brake warning light to stop working. Or stay on. Can't remember. http://www.zcarcreations.com/howto/voltreg.htm p.s. if it's quiet when you're working on it you can hear the relay click and see a spark at the terminal when you reconnect the battery. That tells you that you still have a problem.

I had the same problem. My memory is vague but I think that I found that you could just disconnect the relay and the battery drain would stop. But then the brake light in the dash does not work, for the parking brake or the pressure differential switch. The brake light even acts as an "engine not running" light. It needs power only when the engine is running, to turn the light off. Anyway, I ended up cutting the power wire to the relay, I think it's the yellow one, and tapping in to the fuel pump power line, which is next to the passenger seat. That restored the system to where it only had power when the engine was running. That is the key. The relay needs power when the engine is running only. In the meantime I think that you can just unplug it.

Get the one for your year of car. I have found that the zstore AFM's run rich though. That could be a problem in CA. The old EFI engines take some work to get running right. It probably won't be just a bolt on and go project. It's possible that you don't really need a new AFM unless you don't have one at all. Have you done the electrical tests on it? Good luck.

You might be on the right track. The relay is under the passenger seat. What wiring scheme did you use to get rid of the external voltage regulator? There are at least two common ones.