NewZed

I have my own RT style mount with the urethane GM mount, hanging the diff nose from above. No bottom mount at all, just the crossmember with no mount on it. It's quiet. I had urethane mustache bar mounts though and had to do some spacing with washers to keep the urethane from transmitting diff noise to the cabin. So take care to isolate the mustache bar mounts also if you want to make it quiet. The key to keeping it quiet is to allow just a small amount of play in the bushings. Don't clamp the urethane down tightly. With a stock rubber mount on the bottom you could leave a small air gap between the snubber and the diff to avoid noise transmission. You'd want a new rubber Nissan mount though to avoid thumping/clunking. The thump comes from the diff nose dropping down after lifting during acceleration. The T3 mount is kind of overkill with the wires because the Energy Suspension mount has interlocking metal inside to hold it together if the urethane fails. Thats why it works well alone on the top, it's not just hanging from urethane, there's metal in there. The metal is separated by urethane though so it doesn't transmit noise. http://www.energysuspension.com/products/Transmission-Mounts.html

Actually, not sure which T3 part you got. Their web site is too fancy to work through.

This one? - https://technotoytuning.com/nissan/280z/r180r200-long-nose-front-differential-mount This one is pretty popular - https://www.technoversions.com/DiffMountHome.html It mounts above. The T3 version is very intricate but seems like lots of design for the same function. Looks like a work of art though.

That's not what the liners are there for. They are emissions devices, meant to get very hot to help complete combustion of unburned fuel. So that cylinder didn't "overtemp" because the liner came loose. Still not clear why you have low pressure. I think that they are cast-in, and start in two pieces, maybe tack-welded together. So yours might not have cracked, one piece just came loose. You'll probably find that some of the others are a little loose also. The thermostat housing bolts are almost always tight, even on engines that run perfectly. If the gaskets leak just a little bit the coolant gets in to the bolt hole and causes the bolt to rust.

That is weird. You could release the three bent over clips (picture below) and pull the axles, leaving the sealing plate behind. Maybe you'll find something odd. Maybe they fastened the sealing plate on then assembled the CV afterward. People do strange things, like they did on your inboard CV. I posted a link to where my earlier picture came from that showed a source for the axles. They were used on 2+2 280ZX's or turbo 280ZX's. They're hard to find and sometimes the aftermarket parts are different. If you find one at a parts store take your old one to compare lengths. https://picclick.com/2x-CV-Joint-Axle-Assembly-Rear-Fits Datsun-280ZX-253130612896.html

jhm makes a good point about solid diff mounts and noise. The early R200's had loose tolerances on the gears and they tend to howl or whine or warble. Nissan put a lot of effort in to isolating the diff from the body with rubber bushings. The clips are installed in the diff before the axles are inserted. They spring open as the axle slides through then close up in the axle's groove. Here are a couple of old threads about problems. Don't know why I find this topic so interesting...

This might be the cause of the noise and/or damage. These should be solidly locked in to place by the circlip. You should have needed to pry them out. The inverse of the problem I mentioned above, difficulty removing the axles from aftermarket diffs, is that they can also be difficult to insert. Some people just leave the clips out, or destroy them by pounding the axles in. You'll know when it gets taken apart. Might actually be cheaper to just buy a new one.

Sorry, when you said "carrier" I thought that you meant the diff. The outboard side is usually called the hub. Anyway, there's no locating ring or anything to stick on that end of the axle. That thin piece of brass-colored metal is just the grease containment seal for the CV joint. I'll bet it's just stuck on some new paint on the hub. It's just two big flat surfaces pressed against each other. Here's what the end looks like. A rubber hammer will probably knock it loose or some careful prying. It's not a sealing surface. Edit - make sure that the CV housing doesn't come off of the sealing plate though. You'll get grease everywhere. You can see the little tabs that hold it on. https://picclick.com/2x-CV-Joint-Axle-Assembly-Rear-Fits Datsun-280ZX-253130612896.html

Sounds like you have a 280ZX CV shaft. They still just pop out from the carrier, like the shorter 280Z shafts. There is a circlip inside that fits matching grooves. I have used an oiled chisel to drive between the housing and the shaft to lever it out. Apparently, though, some of the aftermarket diffs have a tighter fit and the circlip can be difficult to get out of its groove. Here's a diagram from the 280ZX FSM, showing the complementary grooves and the circlip inside. The clip should stay inside the diff.

It's a spacer for the flex plate. You need to remove it anyway to mount your flywheel. Pretty sure it just pries off easily. Then the seal will be exposed.

Vacuum leaks tend to be most significant at low air flow. At high RPM there's so much air going where it's supposed to go that the small leaks become insignificant. You could have the injectors tested pretty easily. Here's a shot of some flow test results from injectors I had on my 76 that actually ran pretty well. I tested them myself at full flow rate. It ran a lot better when I got a matched set on it. If you're handy you can figure out how to short the injectors at the ECU and let them squirt. Pop the rail with injectors and give it a try. Beware the gas fumes and sparks.

If the spring was bad or stuck the coil spark would have been jumping the gap all of this time. That would cause more heat and ozone and wear on the electrodes. My mistake on the ballast resistor. Later cars have an extra terminal to bypass the resistor for hotter spark. Apparently 1972 does not. Since the engine's not blowing up your best option might be to just buy two of a higher quality cap and keep the extra in the car as a spare. Good luck.

How long ago is "used to". Could be a mouse nest in the air filter box. And you only confirmed that #6 was involved but didn't do the same for #5. You might have one dead cylinder instead of the two that you though. 82 would have a catalytic converter also. Make sure the exhaust system is free-flowing.

The XR700 is just an electronic version of points. That's why you still need the ballast resistor. The PS40 has 1.4 ohms primary circuit resistance which is very close to the 1.5 to 1.7 ohm range of the stock coil. Lower primary circuit resistance is how they "up" the performance, so yours is on the barely improved end of the performance range. The coil should only be running hot if the new ballast resistor is lower resistance than the stock one. Or if you wired it backward and have the resistance bypassed. None of those should cause your distributor cap to self-destruct though. Looks like you just got a low quality or defective distributor cap. The current that passes through the cap is very short time frame and very high voltage. They're designed to take huge voltage. Your problem looks mechanical. Good work though on the troubleshooting. A new high quality cap should get you right back on the road. Everything else looks pretty good.

Burleigh was making them a few years ago. @BURLEIGH

I have some plain old Tokico non-adjustables that I could sell you. I only have three though, one got damaged. I've been looking for a fourth for a long time but it's not going to happen. A pair might keep you going. I think the damping rate is similar to the middle setting on your Illuminas. I'm in Washington County, by Portland.

As far as the diff, propeller shaft, and half shafts go it's all just like a 280Z, except for the diff mount. The length of the propeller shaft (the main drive shaft) is different but the diff and half shafts will swap between S30 and S130. Your problem sounds more like u-joints. If you don't have a turbo car or a 2+2 you will have u-joint half shafts. So that's six u-joints total for your car. You can figure some things out under the car with a strong light and a prying tool. Pry the u-joints around and look for any movement, they're tough you won't break them. Grab the pinion shaft and yank on it. None of those things should have any play. Won't be surprising if you find some, with your symptoms. Get some sturdy jack stands so you don't end up in the news.

1982 R200's are just like all of the previous long-nose R200's. You'll need to move the ring gear over to the new MFactory carrier. So if your ring and pinion gears are damaged you'd probably be better off finding an R200 in better shape. Otherwise, if the ring and pinion gear are in good shape, and the pinion bearing, you'll be installing new carrier bearings anyway, and the diff will have new internal gears, so it should be a standard swap. So...what do you mean by "big crap"?

It might have been. The piston in the slave could have pushed forward allowing fluid to escape and air to get in. The rubber dust cap will hold it in, it's a tight seal. Easy way to tell is to pop the rubber dust cap off. You can do it by finger with everything assembled. If a bunch of fluid comes out that's a sign. Be careful, the dust seal can hold pressure and fluid will squirt. Also possible that you didn't get the throwout collar clipped/positioned to the fork correctly. Put it on the wrong side, maybe. No offense.

One last thought - the tick-tick-tick noise you heard early on could also be a broken pressure plate part rattling around. Or somebody might have dropped a nut or bolt in there. Lots of little crannies to get stuck in.

Seems like you're stuck in a "think loop". You need to do. Think-do-think-do... If you think it's the transmission, find another to bolt on there. 90% of people who have a Z have their old 4 speed sitting around somewhere. I do. You didn't sound so confident that the motor might not be the problem, in your first post. You put "I think" after your comment. Why would you take it back to the guys that might not know what they're doing? You're just going to watch them do the same thing that didn't work the first time. My car had a lot of heat through the shifter hole when I was missing the rubber seal. That was with everything working perfectly. Just a lot of hot air down there. If you want to get a little crazy, drill a hole in your transmission so you can see the input shaft. Maybe you'll see a misalignment as it spins. Or, here's a way to be sure that the input shaft is not turning - put the transmission in gear with the rear tires locked. Maybe on jack stands with the parking brake set. Hold the clutch in and do the rev test. The transmission input shaft can't turn so all you have is the pressure plate and flywheel spinning around the clutch disc. That takes all of the rotating part of the transmission out of the picture, but with everything hooked up. If you still get a vibration make note of any burning clutch smell, in case you're not getting full disengagement. Don't do it with tires on the ground, if your foot slips you might blow a hole in the back of your garage. Or just make sure it's pointed the right way. One last thing on the pressure plate. Maybe it has some broken parts inside, they do break. That might be why they had to get so crazy with their drilling and welding. The loose parts might be moving when you press the pedal, maybe the thing is unbalanced now. Of course, if that's the case, then it would make sense to go back to the balancing guys. Or just swap pressure plates. Just suggestions. Good luck. Thanks for the puzzle.

Are you sure that motor is designed to handle that amount of mass on the end of the driveshaft? Maybe it's the wrong type of motor.

I've seen many times where the assumption that the one thing that should be the problem can't be the problem because it's already been checked or fixed, often ends up being the wrong assumption. Everybody is suggesting, in essence, that you try another flywheel and pressure plate. It's the obvious next step. The Nissan flywheels and pressure pates are all externally balanced. Any parts you grab should be worth a try. Your balancing guys did a crazy amount of work on that pressure plate. Very abnormal.

It's just another part of the system to make sure is right. A bad bearing, broken "nose" piece on the transmission where the collar rides, cracked clutch fork, worn out pivot ball, clutch fork not seated properly on the pivot ball, etc. Anything that could be causing uneven force or imbalance on the pressure plate fingers.

His main point was the collar, AKA sleeve. The part with the two ears on it that the clutch fork sits on. It needs to match the pressure plate. It's possible to get a tall pressure plate and a tall collar and have the clutch partially disengaged at rest because the collar is pressed against the front of the transmission cover. It's a good point. Here's an old thread about how to go wrong. https://forums.hybridz.org/topic/43715-changing-the-slave-for-more-pedal-throw/