Zed Head

Not much past the surface.... You should just blow the dust off, get it restarted and running, and make it a time capsule car. There's a bunch of restored cars out there already.

I don't remember much from my carb days but I do know that if it runs well at higher air flow levels but has problems at low air flow, that's usually a sign of a vacuum leak. Vacuum leaks get over-powered at high air flow levels. This is true for EFI also. So I might focus on small air leaks. With carbs those can be at the mounting gasket surface, or the intake runner to head surface. I know somebody that spent a lot of time with similar problem and it was a cracked base plate on the carburetor. That was a late-model Chevy V8. A test the EFI guys use will also work with carbs I think. Get the idle speed up just enough to keep it running. Then spray carb cleaner or starting fluid at the places you think might be letting air past the carbs. If the air doesn't go through the carb it doesn't pick up any fuel and you'll get a lean condition, with stumbling and poor running.

Missed that one. How many miles on the engine? I wonder if it's one of those "ran when parked" cars. Is penetrating lubricant really lubricant? And how much oil gets thrown up from the crankshaft at cranking speeds? Does it even reach the swept area? Just being tribological. It would be pretty cool if it cranked up and ran well after 34 years. You need to add a car to your sig now.

You turned it over completely dry, no oil squirts in the plug holes? Ouch. There's still time. Don't forget the valve train.

I don't have experience but I know that it's going to be weaker than an R180. But it will be lighter also. Are you looking for dimensions, or parts needed to mount it in your 240Z?

Sounds great when the RPM go up. Firing order and timing seem right. Any way to just turn up the idle speed to keep it running, so that you can mess with it? I don't know SU's.

He posted over on hybridz.org at the same time and "Globerunner513" gave him this link - http://www.300zx.cl/ga/300zx/images/serial number Datsun Z Car.htm Probably doesn't need the thread anymore. It did turn up a nice reference though, if it's correct. Seems to fit the numbers shown above, and my car. A dead cat bounce is when a small good thing happens after a big bad thing. Like when stock prices go up after a big crash. Kind of dumb financial term.

How big is the hole where the spare tire would go? What do the bumper ends look like even though they're off the car? Is the fuel rail multi-piece or one piece? You're gonna have to put a little bit of work in...

My 76 has one key that does everything. And my 1995 Nissan key from my other car will start the Z, but won't open the doors.

Also look at the fuel rail on the engine. 77 had the three piece, connected by rubber hose, 78 had the one piece. The rubber on the bumper ends is another good clue.

He has a fuel pressure gauge inline apparently. So that should tell if there's a clog. Just saying, he's already head of the game, with the gauge. This just reminded me of the other big sneaky thing that gets people - the fuel pressure regulator (FPR) might have a hole in the diaphragm. Pull the vacuum line off of the FPR and check it for fuel. It kind of fits the symptom, with a small hole getting bigger. The diaphragms get brittle with age. I have an old one that cracked in to pieces when I took it apart.

That's a pretty good clue. Plus the fact that it runs better with vacuum leaks. The fact that it slowly got worse is odd. But it definitely sounds like too much fuel. So that could be injectors staying open too long (ECU controlled) or the CSV leaking (easy to check), to the AFM sticking (also easy to check). Could be that somebody tuned the engine to run with vacuum leaks and when you remove them it runs poorly. Can you crank up the idle speed so that it stays running? That will allow you to examine the parts that could have been "tuned" to incorrectness. I would pop that AFM cover off first thing. Make sure that the AFM vane is moving. Its position has a direct impact on injector open time. It's not uncommon for them to get stuck.

You haven't provided any numbers so it might be that you're just using continuity as your test indicator. You can get fooled on the coolant temperature sensor (CTS) if its connector is attached to the thermotime switch. Make sure that the CTS is correctly connected. Get an actual resistance reading at the ECU and compare it to the temperature chart in the FSM,or the Fuel Injection book. Since the black cover on the AFM is already gooped up with silicone you might as well pop it off and watch the big weight move while the engine runs. Make sure it's moving freely. They've been known to get stuck, showing more air to the ECU than actual. Make sure that your idle setting is high enough to keep the engine running when things are right. Maybe it's set too low and the engine needs the extra air from a loose hose or two. Just thinking outside the box. At least it runs so that you can mess with it.

How do the spark plugs look? Easy to get to and might give you some clues. One reason to do a little detective work early is because you might find that the engine is not "refreshable". Hope that's not the case, but something like a big scratch n a bore can add a lot to the cost, to fix. Better to know now than have the mechanic tell you in a couple of months. Might make your L28 decision easier too.

Just to add to the possibility, and because it could be a while before anybody gets a chance to actually look at the bolt. I snipped a few pictures from the carparts site. The drawing shows line on the mustache bar bolt which seem to indicate a change in diameter, but none on other bolts. Don't know if it means anything. Maybe a draftsman knows. The FSM picture looks like an actual taper, but 2/3 up, with a step. I've never looked closely at the bolt in the several times it's been exposed. Now I have good reason to remove one of those bolts if I ever find another Z n a wrecking yard. They are much sparser now than they used to be just a couple of years ago.

There has to be a used L series engine out there somewhere that you could swap in. They're surprisingly durable. Even a junk yard engine would probably get you by. Despite the weird noises there's always a chance that it's just a head gasket. Might just pull the head first. And/or drain the oil and see what's in it.

Are you using the FSM drawings? You need a reference. I install mine by putting all of the springs in to their respective holes, laying on the shop floor, then grabbing both shoes and folding them like a book. Keep tension on them to keep the springs from falling out. Place the proper contact points on contact points and open the book, pressing the shoes on to the backing plate. The springs will stretch as you get things in place and the book will try to stay closed. Then use a knee or a friend to hold them there while you install the little retainers.

I did measure the hole in the top stopper though. 15.7 mm. So, approximately the stud/bolt size.

No pics but I distinctly remember that the washers that came with my bushing kit had different sized holes. I put the small one on first and had to take the bar down to swap them because it got jammed halfway up the shaft. If somebody has a kit they might be able to measure or eyeball. I think that I have the old factory stoppers out in the garage that might show the same. I'll dig around. Edit - found the parts and took some pictures but realize that they don't confirm a taper. The small one fits on the step on the end of the shaft, for the nut and washer. The kits come with a sleeve that fits over the shaft, so the washer with the small hole only has to be smaller than the sleeve hole. A different system. Could have been "wear and tear" taper, and the washer that came with the kit, that was only needed to not slide over the sleeve, "almost" made it up the shaft. Maybe a non-issue.

Not sweating, just getting facts straight. American technology. Probably American tape. The final puzzle is why the schematic looks British. (emoji here).

It gets more interesting - Compu-Tronix is apparently taking credit for 3906920 now. Whoever they are. http://www.hotrodhotline.com/pr/2011/compu_tronix_american_v8/

It's still undefined. Per-Lux is a mystery firm. You're right though, there doesn't seem to be a U.K. link. Is Hemphill a British name? Maybe that's it... https://www.google.com/patents/US3906920 He's looking Californian, Silicon Systems. https://www.google.si/patents/US3581720 "both of Balboa, CA" - Then Fountain Valley in 3906920, above.

That bolt/stud has a taper. As anyone who got their washers mixed up from the typical PU bushing kit would find out. Don't know why.

Bessie that, assuming that all "tape" is the same and that a good engineer couldn't specify one that did the job is a bit misguided. The tape has worked for thousands or hundreds of thousands of people for hundreds of thousands or millions of miles. It's simple, easy to manufacture, and apparently cost effective process, based on the price of the final product. It's been working fine.

Typical corporate hype story, distributed around to various parts suppliers to make the brand look like it has history. Doesn't' say anything about where Per-Lux started, or who "the engineer" was. He could have been a Lucas engineer.