NewZed

Hey @RETRO-SPEC

Here's two thoughts - 1. Check voltage at the coil. Maybe your voltage regulator is going bad and "over-volting" things. I don't know how a tach would react to that but it's a possibility. 2. Spend $25 for a GM HEI module and wire it in quick and dirty. It might actually make things worse, sometimes they cause their own tach problems, but it might tell you something. Always good to have a backup ignition module anyway, the 40+ year old modules die on a regular basis. Two cheap checks, compared to new gauges. Good luck.

Does it match RPM? Could be a sign of a failing ignition module. If the flasher makes noise then it must be getting voltage. Current flow heats and cools the mechanism. Always possible that the bulbs are burned out. Also, check the grounds. Can't remember if the tach signal lights have their own ground wire from the socket or if they ground through the socket to the tach body. Who knows, poor ground might also be the problem with the tach needle. The ground circuit is often overlooked. I've also found that the bulbs and sockets can be pretty touchy. They have to be just right and are easily knocked loose. Once you get in there sometimes the problems just grow. I got the fuse cover picture from the 75 FSM. You might have a more 76 like system. 75 had a lot of firsts, and new changes. Here's 76.

What does "lazy" mean, in tach terms? Is the ignition system factory stock? Do the lights flash when you turn the emergency flashers on? Have you checked the fuse? Does the flasher unit make noise?

My mistake, I was thinking clevis pin. You could cut the rod in the middle and insert a tall nut, maybe. Or put a bolt/screw through the back of the clevis and use the tall nut as an extension. Spitballing... Example - https://us.misumi-ec.com/vona2/detail/221005295770/?rid=rid3

You should find a shop that knows Z cars and Quaifes. The wrong shop could waste a lot of your time. There are many people out there that are happy to guess, on your time and money. The "clip" problem is pretty well known by people that have worked on the Datsun diffs. A 510 shop would probably know also.

That's the basic problem, I think, the groove shapes are different. Nissan changed the location of the clips around the time that they introduced the VLSD diffs. If you get a VLSD diff, like from a 90's Nissan, the clips will come out with the axle. If you have an early open or CLSD diff the clips stay inside. I think that if you get two square grooves combined you could end up with a stuck axle. Better inspect things closely. Your shop is probably use to looking at VLSD's like on the 240SX. There is a lot of confusion on the CV axles. Some places even show the 240Z's used CV axles. There's bad data out there.

Looks like they changed over the years. #10? Might be available from Nissan. http://www.carpartsmanual.com/datsun/Z-1969-1978/brake/brake-clutch-pedal https://www.courtesyparts.com/oem-parts/nissan-pin-clevis-46123h850a

Most strut/insert manufacturers recommend bump stops. Probably in the instructions of whatever you end up getting.

Connecting direct to S might work. There is an electric connection in the switch that opens and closes that first magnet valve. It's described in the chapter. Not clear what would happen if you still have vacuum when you turn the heat to Off. I can't remember what actuates the first magnet valve. Without a vacuum bottle the valves will open and close with engine vacuum, probably, even with a check valve. Cold feet on the on-ramps.

It's 36.3. You should check between filter and rail. If you're getting 60-70 before the filter you might have a clogged filter. But, in short, no offense...you're doing things wrong. Stop the random stuff and get in to the FSM or the EFI Book and do things the recommended way. You'll save time in the long run.

zhoob he doesn't have the mechanism to control the coolant flow or the air flow. Both are vacuum controlled. No vacuum, no heat. I had a vacuum hose that used to split on a fairly regular basis. I would know immediately that the hose had split because the heat would stop. No vacuum, no heat.

These early EFI systems need the basics to be right-on for everything else to work right. Guessing won't work. Get the 1980 EFI Book, or the 1983 Service Manual (FSM) and make things right. Your fuel pressure is way too high, for starters.

This part is actually the joint between the two rods. They put it together backwards then got confused. Pop it apart there and flip it over. You'll need to remove the hooked portion at the end to get it free. It's supposed to slide, I don't know why they put those hose clamps on there unless it's too short. Your 280Z manifold might have a longer rod that you can swap over. Take it apart and put it back together with more puzzle pieces.

It looks like they put #2 on the bottom instead of the top. Pressing the pedal would close the throttle not open it. Does the engine run? Does the pedal work at all? Looks backward. It's messed up, but probably fixable.

It looks like somebody could probably make that work. Easier than swapping intake manifolds. There is a lot of adjustability in those rods. Take a close look and you'll see that they are threaded on the ends. Pop the plastic end off of the joint and you can screw the ball in or out to make the rod longer. The wood piece makes me think that they broke something when they did the swap. That's a hack job. There's a bracket there that should hold up that end of the linkage.

Sounds like a vacuum leak. Check your hoses.

The RB wouldn't have anything to do with the heater functions, compared to the L6. All it does is supply the hot coolant and the vacuum. You need those valves. Not much you can do except put it back like it was, or study the diagrams and make it work. There's no tricks. The AC chapter has the good drawings and descriptions. Some of the controls are mechanical and some are vacuum operated.

V8? Dual.

What you did here does the same thing that the relay will do. Good luck.

Looks like it's in very good shape. I like the bumpers.

Do you have a camera? Pictures are always good. Not sure but I think that most people would put the 280Z parts on to the 280ZX engine. The intake and exhaust manifolds. Since the ZX is a different body style it wouldn't be a surprise if the throttle linkage didn't swap over right. You could use a cable linkage.

You probably want to see these mods. It's not a "survivor" 78 280Z. "Replaced" doesn't mean that he replaced with 280Z parts either. The headlights and bumper mods will change the outside appearance. The LED gauges and white faces will change the inside. The headers and converter delete will make it louder and it might be droney. People tend to overvalue their personal artistic interpretations.

There's a whole thread over on another forum about mistakes we've found in the wiring diagrams. Looks you've ID'ed a new one. Use a meter though first and check continuity to the plug at the fuel injection relay to be sure. If you're not positive. Always possible that Nissan used two similar plugs, to different things. You might have the blue wire plug plugged in to something else.

Here's one that looks similar except it shows them as green. The other end would be at the fuel injection relay.