Zed Head

You're descriptions are hard to grasp. Shaking real bad, not lurchng or lunging, grinding, combination of both? (both what?), hard to get in to gear, once you get going no issues... It sounds like you're transmission is going bad along with your clutch and clutch cylinders, and your engine, transmission and differential are about to fall out. A short story from when you start the car, to putting it in to 1st, releasing the clutch pedal, moving and shifting in to 2nd would probably be informative.

It's the distance of the spring surface of the pressure plate from the back of the engine (its height) that matters, where the throwout bearing rides. If you're using a 280Z pressure plate, you would probably want a 280Z throwout collar. This is true for the later transmissions, but the early one that you have might have a different mounting spot for the slave. It might also use a different slave cylinder. I don't know all of the details of your engine and transmission, but if it worked before and you have the old parts, you might look at the distances and relationships of the pressure plate spring surface, slave cylinder and slave mounting point. I have the critical distance for a 280Z but it might be different for what you're using. By the way, if the clutch is seized and won't release the engine from the gearbox, then it is not "engaging". That's what it does - engage the engine and the gearbox. It's already engaged, the slave cylinder disengages it. One more thing - new slave cylinders have been known to be bad from the stores. You have to measure travel to know if they're getting full movement. I had one that moved about half of its travel, it looked like it was working, by eyeball, but it wasn't

Check your motor mounts and the transmission mount for looseness. Is there any reason your clutch would be worn out? Shuddering is usually due to an uneven friction surface. Transmission problems would probably show up while driving, without the clutch being used.

Still looking for a home for that thing huh... Have you tried zcar.com?

If the early PCV valves are just ball-type check valves then gravity is a factor and proper installation comes in to play. I didn't know that the early ones were of that type, maybe that's our difference here. Back to the OP's problem though, a full engine rebuild due to some milky oil is a sign that someone wants a new engine:classic:. Water is a byproduct of combustion (watch your exhaust pipe when the engine is cold) so, with a little blow-by and many short trips water buildup is still a likely cause of the water in the catch can. A few simple tests would tell the full story.

This is actually a sign that the "breaker" circuit in the Unilite was not being activated. When you turned the key off, the circuit was broken and the coil discharged like it should. You don't need the cap on to get a discharge from the coil (as you saw). The Unilite is optical so either the "light" never shone on the sensor or it was shining on the sensor but nothing ever blocked it or there was no power to either the light or sensor. I would bet that there was no power to the light and/or sensor. When it's powered correctly I believe that you can even trigger the spark with a piece of paper, sliding it between the light and sensor.

The text from the FSM doesn't say that the valve is normally closed. It says that the flow direction changes and shows a drawing of flow coming from the valve cover hose under high blow-by conditions, because the crankcase gets pressurized. And yes, I did blow through both sides and also noted that the valve plug is held in the middle of its travel range by the spring. I just went out and confirmed on an old PCV valve in the garage. It was from a 1981 ZX though. But I looked at a 78 Z valve also, in the past (one advantage of hoarding). When I was working on it I wondered if the spring tension is tuned by the engineers to allow a certain amount of flow, since different engines have different part numbers (at the auto parts stores) even though the outside form is the same. I ended up putting a Z valve on my Pathfinder just to be contrary. It works fine (by the way, the original reason for even looking at it was milky oil on the filler cap). Not trying to be argumentative. I was perplexed when I was working on it because I thought that it should be normally closed then open under vacuum. But you can poke both sides of the internal valve plug with a small screwdriver and it is definitely balanced in the middle, at the end of the spring. If you Google PCV valve you'll find a ton of descriptions with illustrations showing low flow at high vacuum and high flow at mid-range vacuum. Closed at backfire. There's actually a current thread over on Hybridz about the PCV valve on a turbo engine. It seems to be a more complicated part than you would think from its external appearance.

I do but I can't recommend that anyone build one. It's a dangerous device unless you use a gas substitute. I used gasoline and was super careful, but even so I don't think I'll ever use it with gas again. It made me too nervous, especially with the Bosch injectors, which really vaporized the fuel, compared to a stream from some other injectors. I'd have to locate a less flammable substitute liquid.

There are several this's in my post so I'm not sure which "this" you're referring too. PCV valves have a spring inside (I'm sure you know this) that holds the valve partially open (this might be where the different view comes in). It's a normally open valve, restricted at high vacuum or flow rates, closed completely by backfire. So with no flow from pressure differential to close or open the valve the gases will just float through and fill space until they hit the cold can and condense. I only know this because I had a plugged PCV on my Pathfinder and after removing it and cleaning it up, I had to go to the FSM and the internet to confirm how it was supposed to operate (because I could blow through it both ways). It's a little more sophisticated than it seems, with a two way valve that is designed to move both ways at certain pressures. Purty cool.

The most noticeable effect for me was a smoother idle, and smoother high RPM running. Due to a better power balance between cylinders, I assume. I had one of those sometimes leaking injectors also, and later I built a tester and found about a 20% difference in output from high to low in the old injectors. They were pretty bad. Also, now that all ports on the fuel system are sealed, the engine starts right up, even after days of sitting. No leak-down. Did you plug the fuel line to the CSV or just disconnect the electrical?

It sounds like the catch can is doing what it's supposed to do. The way you have it set up is like a distillation condenser in a chemistry lab. Moisture vaporizes in the hot engine, the water vapor makes its way to the can and condenses as water in the can. If you wrapped the pipe/hose from the crankcase to keep it hot until it gets to the can, then the sludge would probably only collect in the can. And I don't think that there's a P in your PCV, since you aren't applying intake system vacuum. It really is just a distillation device for water, from the oil. If you moved the hose from the valve cover to an intake manifold port, and blocked the filter, then the PCV would work like it was designed, I believe. Probably keep your oil cleaner too. Or you might collapse the catch can like a cool science experiment.

You should be able to remove the rail, FPR and injectors all as one unit. It's easier to install the injectors first though, then fit the rail to the hose ends in the reverse operation. For me anyway. And don't forget the bracket in the middle of the rail that is held by one of the four intake manifold bolts. I think that it has got me every time. When you're bent over the fender to work it's hidden behind the rail and easy to miss. You'll think everything is unbolted and some invisible force is holding the rail on.

Just curious, but what year Z has a 2 liter oil catch can? How often do you drive the car, and how far each time? Maybe you just need to drive it farther on each trip.

I have used the vacuum ports on the intake manifold to apply starting fluid. It doesn't take much. Pull a hose off, squirt just a little fluid in (about a half second burst), put the hose back on, and try to start it. If it's a fuel problem it will start, rev, then die. Make sure that you use real Starting Fluid and not something that seems like it should work because it smells like a petrol derivative. Electricity for spark passes through the distributor cap so you can't try to start without it on. Maybe you meant crank the engine? You can crank the engine with the cap off, but I think that you should ground the main wire from the coil if you do. Electronic ignition doesn't seem to like it when the spark has no where to go.

It does look pretty cool. I assume that the other end of the cable is attached to the heater control lever in the AC control panel. How does the throw at the panel match the throw at the valve? And have you tried it yet? Do you have a cooler cabin now?

Monroe's "How To Rebuild..." book says to put a bolt in the threaded hole in the cap, lay a 2x4 on the block, then put a pry bar under the bolt head and pry it up and out. It's a good book to get, if you don't already have it.

I run a flat bastard file very lightly over any flat surfaces once most of the gasket is removed. If it leaves marks on the metal around a remaining patch of gasket material I leave the gasket material as surfacing filler. Flat and smooth is the key for good sealing, not shiny. There are some good stories on other forums about heads and other parts being ruined or close to it through efforts to removed all traces of gasket material. Aluminum is soft metal.

Here's a good link - http://www.datsunstore.com/index.php/page/2/sort/2a/cName/engine-z-cooling-and-heating Might be easiest just to call and talk to Oliver.

Good luck with the manual boost controller and the RRFPR. I've still not seen anyone report that this method gave a civilized upgrade. Boost can be increased without blowing up the engine, but there always seems to be other problems that crop up. Interested in how it turns out. When you say "OE ECU", do you mean OE NA 1977, or OE turbo 83?

More on the oil behind the seal - I am fairly sure (not certain though) that there is a drain hole or slot at the bottom of the main bearing cap between the seal and the bearing. There's a gap between the seal and the bearing for sure, so no reason for oil pressure buildup. I also have faint memories of shining a flashlight in there while changing a seal and realizing that I could see in to the crankcase. I don't see any reason for oil pressure to have anything to do with the leaking seal. The oil should be fed in to the bearing, run out the sides and down in to the crankcase. Of course, I could be way off. Edit - there might be a way for pressure to build up if the drain hole (if it exists) was clogged. Maybe that's the issue.

Seems to me that that seal area is not supposed to get pressurized. Your oil pressure is good, the oil just doesn't have the proper return path to the crankcase. Looking at various pictures of the bearing cap and bearing, for whatever reason the gap between the bearing and the seal must be filling with oil faster than it can drain out. I would focus on that aspect of the situation, rather than oil pressure. But I've not had an engine apart so I'm just going off what would make sense if I designed an engine. Maybe Nissan did something different.

I think that he's looking for the multifunctional relay that has the alternator circuit and the oil pump switch circuit running through it to control the fuel pump power. The one that they used from 1978 on. Probably still work-aroundable, just not a simple circuit.

If the oil is clear, not milky, then light brown is normal. Water in the oil gets frothed up and creates an opaque milky emulsion. Looks like your problem might have nothing to do with cylinder, pistons, rings or valves. Your pressure numbers look very good. Maybe you just bent your throttle linkage in your haste to get the RPM back down. Have you tried adjusting the idle to see if things get back to normal? In retro, reading back, you've only described a low idle RPM as the problem. How does it run otherwise?

Rotating the engine backwards. Not a big deal. Rotate it forward and it will probably tighten up.

Thanks for the details, sorry that I misinterpreted your comment. Shouldn't it be called a differential "pressure" test though, since there's no compression involved? Pressure from an air compressor (air compressor compression doesn't count does it?) instead of piston movement. Just sayin'... But cylinder pressure testers are pretty common and inexpensive and the easiest if you don't have an air compressor. Based on the signs, he'll probably get some zeroes or teens and have to pull the head anyway.