NewZed

The obvious one is the coolant temperature sensor. Are you really in Poland, or just goofing? http://www.nicoclub.com/FSM/280z/ Engine Fuel, read the chapter. Also, you'll get better ideas if you are more descriptive than "playing". To some people that means hitting with a hammer,to others it's going through a complete calibration process.

Haynes and Chilton aren't Factory. They're just simple notes on what might be right. "B. The distributor even though I'm getting spark maybe it's not working properly and yes I switched it 180 degrees and checked both ways to start it" You swapped your distributor around and back, but you don't need to do this. Just verify the notch and groove at the cam sprocket, and the damper timing mark at zero, and the cam lobes up (not straight up, just valves closed), and the distributor rotor pointing forward, all pointing or oriented the correct way at the same time. You can verify proper orientation of numerous parts all in one step. Get everything lined up and correct, then pick #1 on your distributor cap, put #1 in and fill the rest of the holes in the proper order and rotation direction. That's the procedure. The guys that throw their engines together and fiddle around to make them work know how they operate so they can do that. But if you're not clear on that, you need to start from a solid base. Good luck.

You're not measuring anything. The only numbers in your entire post are "83 280". The injectors should not flood the engine. They might be shorted. Measure voltage at the connections with the key On. The method to confirm camshaft timing is described in the Engine Mechanical chapter - notch and groove, not "8. Engine was at tdc the cam key was straight up and the sprocket had number 1 pointing straight up". Correct firing order and rotation for plug wires is out on the internet somewhere. The method to confirm proper orientation of the distributor rotor is described in Engine Mechanical also (how did you replace the HG without seeing these things?). The NA ECU doesn't have any lights. You should put a proper procedure together, not a list of things from the internet, follow it, and write down what you measure.. Go through the Assembly subsection of the Engine Mechanical chapter of the Factory Service Manual. Start from scratch. Good luck.

Check your Air Regulator. It's purpose is to let extra air past the throttle blade to increase the idle speed at cold start up. They can get gunked up inside, or the electrical connection can corrode. You should have about 1000-1200 RPM idle speed for a few minutes right after a cold start. You might just have too low idle speed.

Is this car new to you, or is it an old car with a new problem? You said that the engine runs fine when it's warm. Valve lash increases as the engine heats up. Checking lash would be a good idea. You might have a valve not closing when cold, causing a dead cylinder. That's very bad.

I got "motivated" 'cause you challenged my description of his motor as "new" (it's pretty common to see less than 10 miles on a new car's odometer), then took it further with the valve float comment. That's just how the world works...

So, back to the OP's issue - If the oil is clean you could just use what's in there. Probably full of ZDDP. Nissan factory spec. Drain it to make sure no water has condensed in over the years, although those cam lobes look like they've been pretty dry, then pour it back in. Then use one of the several oils recommended here for the first oil change. I'd dribble some oil over the lobes and rockers before turning it over to prime. The lobes look like they've drained completely dry of any oil.

Not mad. You sounded like you knew something with this post, but apparently you were just making things up. If anyone's agitated, it's you.

It says the first 1000 miles is critically important. Which is the regime the OP is in right now. It doesn't look like you've been keeping up with cam and rocker damage horror stories.

That's what I thought.

You should give numbers. Timing, fuel pressure, pretty much anything that can be quantified. And what does timing do when you rev the engine.? Does it advance? Valve lash is easy to check, even if you don't adjust it. Turn engine, stick in feeler gauges, write down numbers.

Some places say they have NOS. http://nissan.dealerdirectparts.com/Nissan-Part-number-54320-N3701-p/54320-n3701.htm http://www.carpartsmanual.com/datsun/Z-1969-1978/axle/rear-suspension/9

Describe "factory run-in". From 1981. Use details.

People have had your problem. You just need to find the nut from inside the car and replace it if you can't fix it from below.

All of the ideas are out there. You've shown that the driveshaft is not firmly connected to the engine or the rear wheels. It seems to be spinning in space. The car should not have moved at all before the axles twisted, from what you've shown in your videos.

Aren't you screwed right now? You'll be in the same state, but at least you'll have tried something. http://www.carpartsmanual.com/datsun/Z-1969-1978/engine-240z-260z/engine-mounting/manual-from-c-hls30-46001-rls30-grls30

So, basically you're saying that you have a freshly built engine that has not been broken in. The main worry then would be the camshaft lobes and rocker arms. Zinc (ZDDP) seems to be key. There are a variety of break-in oils out there. VR1 racing oil seems to be popular, as one, for example. Not designated as a break-in oil but it's an older ZDDP containing formulation. People have had issues with using a non-zinc oil with added ZDDP break-in additive. Probably best to find a zinc-containing break-in oil. Brad Penn is a brand that seems popular. http://www.valvoline.com/our-products/motor-oil/vr1-racing-oil https://www.summitracing.com/parts/bpo-009-7120 http://www.competitionproducts.com/Brad-Penn-PENN-GRADE-1-Break-In-Oil-30W-Quart/productinfo/BPO30WTQT/#.V42S89IrKig Read up on failed camshaft swaps and you'll find many opinions but getting an oil with the ZDDP already formulated in seems like a good idea.

Your second video here is where it would have been informative if you could have had somebody press the brake pedal while the engine was running. You had video of the pinion shaft moving and the halfshafts. Pressing the brake pedal would have stopped the wheel flanges. Then things would have been clear, either both halfsahfts would have stopped and the pinion shaft kept spinning or only one of the halfshafts would have stopped.. The advice to remove the diff was a little premature, you were right on the edge of getting some good information..

Here's the original - http://forums.hybridz.org/topic/5380-broken-stub-axle-danger/

Here's another from a guy who broke his just tightening the nut. http://www.classiczcars.com/forums/topic/42487-rear-stub-axle-just-broke-when-tried-to-torque-nut/

Nice. Here's a link on how the 240Z's break their axles. It's titled "STUB AXLE FAILURE". About halfway down the first page here - http://forums.hybridz.org/topic/49194-differential-cv-lsd-hp-torque-r160-r180-r200-r230-diff-mount/

Here's a thought, that might be feasible - you have a broken stub axle in a wheel hub.The bearings will hold the wheel on, sitting in the garage. See if you can turn the wheel companion flanges at the hubs, without the wheel turning. This would let all of the things you've seen happen, without the car moving. It would be like lifting one wheel in a corner. The diffs need both wheels to have some resistance to motion for the diff to work right.

This is a very strange thread. You're not using some sort of odd two-piece splined driveshaft are you? You had a video of the transmission end of the driveshaft but not the pinion flange end. It's still not clear that the pinion shaft of the diff will turn without at least one of the stub axles turning. You have something missing in all of your descriptions and videos, either the wheels are up or the video doesn't show the right parts. If you could clamp the two stub axles in a large vise and use a wrench on the pinion flange you'd be able to tell if the diff is broken. If the diff is broken you should be able to turn the pinion shaft more than you described. "the pinion gear was turning for a brief period". You found a piece of a clip inside? Take some pictures. Down the spider gear holes and from the back. Bright lights, in focus. Take a video from the back with the cover off as you turn the pinion shaft. Lock the stub shafts down somehow and use a wrench to turn the pinion shaft. Something must be broken but it will take someone familiar with broken diffs to know. This should be a simple thing to figure out. Don't make it complicated. Your sig says "LS1" but your video shows an L6.

I think that your clutch is either slipping or stuck in the disengaged position. It's the link between your engine and transmission. With the car on stands there's enough drag to turn the driveshaft and wheels. With the wheels stopped by the ground,it slips. Check your clutch fork first to see if it's stuck pressed backward. If the clutch is jammed open though, the clutch pedal will require very little pressure to move. The slave cylinder rod will be extended. If it's not the clutch, then it's the transmission. Nice sounding engine. Must be a bummer to have it stuck in the garage.

Are the halfshafts still disconnected? If the car is up on stands, put the stub axles back in and put the transmission in gear. Crawl underneath, grab both stub axle flanges at the same time and see if you can turn them the same direction. It's sounding like you will be able to turn them and you have a problem with the splines or your spider gears. You may have broken somehtng when you were trying to pound the old twisted shafts in. The problem you're having in this thread is that you're reporting two contradictory things at the same time. You say the wheels turn when they're up, but they don't turn when they're loaded, on the ground. But you haven't confirmed that the driveshaft is turning when the wheels aren't. That's the key to knowing where to look. Is the main, center, driveshaft turning when the wheels (stub axles) aren't?