Zed Head

Mine came apart like yours did when I tried to take the connector off. If you got a good one from a ZX, it should swap right in. You could have "calibrated" your broken one by clocking the piece that came out, and testing with a battery and some jumper wires until it opened and closed correctly, then using epoxy or similar to lock it in place, but it's simpler to just get a used one and clean it up. They're not really supposed to come apart.

You seem conflicted. Your first statement fits with this forum, classiczcars, your second is more along the lines of the hybridz.org thinking. MY EFI 280Z barely fits on this forum...

If you have original AC, then some of the control is vacuum. I have a 76 with original AC also, and have had the same problem. The vacuum lines to and from the white bottle in the engine bay and the two "magnet valves" (solenoids) have to be intact and the valves themselves have to work. I've had the lines split and also had the round black flow control gismo that the hoses run through (on the magnet valve bracket) clog. There are diagrams in the AC chapter of the FSM. But, I believe, defrost is controlled by both vacuum and mechanical (to close the doors to the foot area in the cabin). I have also lost Defrost because a piece of carpet got stuck in those doors by the feet. The AC/heat control system is almost as complicated as the EFI system.

Had the car been sitting for a longtime before you got it? What you really need to do is download the Factory Service Manual,if you don't have one, and start testing components as shown in the Engine Fuel chapter. Save yourself time in the long run and just go through the tests. There are many causes of running rich and each one can add a little bit of richness. You will most likely not find a single solution to the rich mixture problem. And, regarding a new engine, you'll still have the same problems with a new engine, unless you get all of the EFI parts with it, and they are all in great condition. You're on the typical path of a new owner of an old 280Z. www.xenons30.com/reference p.s. You're way ahead of many people with new Z's since yours actually runs and drives.

Should work. You'll need to extend the wires from the magnetic pickup coil in the distributor to reach the G and W terminals on the module, and figure out which one is positive and which negative. And cover the hole on the side of the distributor, where the E12 module used to be.

After the fuel filter, before the fuel rail, is the right spot. Pull the small wire from the starter, and turn the key to Start to run the fuel pump, after you've charged the battery.

Changing rings to fix a smoking engine is a typical American engine fix from days of old, on the small block chevys or straight sixes or basically any domestic engine from the 50s, 60s and 70s. That's probably why your dad says "needs rings", because that was a common fix-all for old smoking engines. The L engines though rarely waste the rings and/or cylinders. They last for hundreds of thousands of miles. As Leon suggests, measure cylinder pressure and/or do a leak-down test. You might be jumping to expensive conclusions.

I've read of people using Redi-sleeve on the crankshaft rear seal area. I'll bet that you get opinions on both sides though, Redi-sleeve it or just replace the damper/pulley unit. Should be easy to sleeve though since it's off the engine. Good luck, I've not fixed that problem. You probably have it already but here's a link to the Redi-sleeve page - http://www.timken.com/en-us/products/seals/industrial/products/Pages/redisleeves.aspx

Your words are kind of confusing. Don't you have to remove the damper to replace the seal? The pulley is attached to the damper. Where would the grooves be that you're describing? Can't help on the oil slinger, although it's probably described in Engine Mechancial n the FSM.

Could be a vacuum leak. Is the oil fill cap on? Check all of the vacuum hoses on the intake manifold for splits or breaks. Any vacuum leak on an EFI engine will cause problems. No engine needs back pressure on the exhaust system. Urban legend.

Here's another option, but it's in Michigan - http://forums.hybridz.org/index.php/topic/109125-79-280zx-drivetrain-part-out-n47-head/page__pid__1021043#entry1021043

Based on data supplied I would say it needs a tuneup. Plugs, distributor cap, rotor, and confirm timing. If problem persists, take further action. Seriously, there are many things that could be causing your problem. Ran good, now has 10" of vacuum and a miss could be running rich, running lean, timing is off, valve lash needs adjustment, vacuum leak, fuel pressure low, fuel pressure high, bad plug wires, bad spark plugs, timing is off, etc. With EFI, in the long run, you're almost always best off to go to the Engine Fuel section of the FSM and start testing and confirming that things are right, if you know that you have good basics, like tuneup parts. Fuel pressure is probably the most critical spec. and is the foundation for supplying the proper amount of fuel to the engine. Fuel pressure needs to be right, and no vacuum leaks. All air must pass through the AFM.

How long have you had it and what is it's history? Vacuum leaks are the first thing that comes to mind. It's not uncommon for the various hoses that run throughout the engine bay and even in to the cabin to be the original 36 year old hoses. The miss could be due to a leak leaning out the mixture.

Look for marks where the backing plate rides close to the drum. It's pretty easy to ding the bottom of the plate up to where it contacts the drum, or, as you suggested, there could be a piece of gravel stuck in there somewhere. You'll see light colored rub marks on the backing plate of the edge of the drum. If so, a pair of pliers or a small hammer will easily fix it.

Actually, the reason for the T is that both the vacuum advance and the valve on the carbon canister are operated by "ported" vacuum. So the line that runs to the TB is to the same ported vacuum source for both. It opens the valve in the carbon canister and applies vacuum to the distributor's advance module as soon as the throttle is opened. The carbon canister has a pretty big vacuum hose of its own that they must want to stay closed at idle, hence the small ported line to operate the valve.

Looks like you might have found one, although it's not really clear what Diseazd is referring to. For the record, most people who seem to be in the know say that there's no problem running a round-port head in to square-port headers. The complete opening of the round-port head fits inside the square port,so there's no flow disruption. The problem seems to be when running square-port heads in to round-port exhaust. The round port covers the corners of the square port, hindering flow.

An N47 head will work also, and will definitely have the newer valve seats. Although, I would guess that Datsun Spirit will install new seats when they rebuild it, so that may not matter. The range, in years, for cars that have that type of head is 1975 280Z to 1979 280ZX. Either N42 or N47. Might help your search. Also, if you know how much you're willing to pay, it might break a spare head free. I have a spare N42 head sitting in the garage but I'm not really in to the parts selling game. I'm still a collector, but might consider something if it was interesting and easy (shipping and all that). Good luck.

Well, even a reading at higher RPM would tell you something. Disconnect the vacuum advance, take a reading at a known RPM and people here could estimate correctness based on the centrifugal advance curve. Or, even simpler, take the distributor cap off and rotate the engine around by hand until the rotor is pointing at the #1 plug position and the points are just starting to open, then note where the timing mark is. That will get you within a few degrees of your static timing. Good luck. I get the feeling though, that you're focused on timing because you don't know for sure where it's set. If you knew, you'd probably look somewhere else for the source of the problem. My engine will idle with timing set to zero, or twenty or anywhere in between. Initial timing is not usually the cause of a poor idle.

I'm a little perplexed as to why you want to take things apart based on guesses. Why don't you take a measurement? You might find that your timing is perfect and you've been chasing your tail ("it has to be the timing") since the beginning. It could be cam timing. It could be a vacuum leak. It could be the carbs. It could be the "etc.". You should get a timing light and see what's really going on. If someone's telling you it has to be the timing and you don't need to measure it, stop listening to that person.

The OP should post more details about how he got in to the situation. Did he just do some work on the engine? What kind of work? What work besides distributor? What is the measured timing value? Jeff G, any chance that a ZX mount ended up on the 260Z distributor in your case? Maybe even in the OP's case if he started from parts. That would limit the range of adjustment.

It's just a ground wire, from the aluminum body of the AFM to a mounting bolt for the base plate. The AFM is mounted on rubber grommets so, in theory, could be isolated electrically. Someone must have taken your AFM off in the past and didn't put the ground wire back on. In reality, the rubber grommets that I've seen are usually crushed, damaged or gone so the AFM body is grounded anyway. You could check continuity of the AFM body to ground to see if you need the extra wire.

Have you measured the timing with a light? What is the number?

Just saw this today - http://www.datsunstore.com/ Apparently they're moving and have to get rid of some stuff. Says 30 cars must be sold. I thought they just sold parts. Worth a browse.

The voltmeter will always read the battery voltage, key on or off. Is that the "problem"? Maybe you just never noticed it before. The overheating, and its after-effects, might be your bigger issue. The head can warp if it got too hot. You'll find out when you get it going again. Did it overheat 12 years ago, or recently? If it's been sitting 12 years, there could be a lot of hidden problems with fuel and electrical components. They don't like to be un-used for long. If you haven't tried to turn the engine over yet, you might want to take precautions before you pump rusty gas through your fuel lines and filter, and maybe even your injectors if the filter internals have fallen apart. You can save a lot of later trouble, with some foresight now. Have fun and good luck.

Well, so much for my approach then. Maybe you have a problem on top of a problem. When it is "running fine" except for the rich mixture, it would tell you a lot if you could measure fuel pressure while driving. It should be high 20s to low 30s when cruising and jump to 36 when you give it throttle. I had a really tough time diagnosing a similar problem with my 1976 engine because the FPR caused the pressure to rise out of spec. high only when the regulator got hot. I didn't like disconnecting the fuel lines to connect the regulator on a hot engine so I only measured pressure when things were cooled off. I'm not saying that's your problem, but measuring fuel pressure while the problem is happening will at least let you know if fuel pressure is right or not. If it's right then you can move on to looking at other things.