Zed Head

Yes, that is an early L28 ECU, for an NA car. Stock turbos did not show up until the 81 280ZX. Oxygen sensors did not show up until 1980 in the 280ZX's. The number for the AFM should be on the black cover or on a sticker on the AFM body. The most noticeable difference is that the pin-out (where the electrcial connections go) is different. The connectors are similar but the wiring is totally changed. So if that L28 ECU is plugged in and running the engine, the car never had a turbo ECU. It would require the turbo EFI harness. Some people do use the NA ECU and a rising rate fuel pressure regulator to allow a turbocharger to work without blowing up the engine. Which raises the question - is there actually a turbocharger? No offense, but it's not clear what you know and you did not mention one. The L28 NA ECU would probably run a turbocharged engine but it would not have any power under boost. Which kind of sounds like what you're describing. I think that you would have to remove the turbocharger to get the engine to run more close to normal. But it will still be down a bit on power because the compression ratio is low, for the turbo. It could be done but it would be Z blasphemy. In short, it sounds the guy might have swapped in a turbo engine like he said, got it to run using the NA electronics, but never installed the turbo electronics to make it run right. Which is about what he told you.

Does the gear inside the transmission turn with the wheels? You could probably see in there with a mirror. I don't think much oil will drain out of the hole. Jack the back end of the car up to be sure it's higher than the fill hole. That's all I got.

When you installed the pinion gear did you use the complete aluminum assembly or did you remove the little pin and swap gears? The gear is actually offset to one side in the assembly and when Nissan changed the location of the hold-down screw they moved the hold-down slot to the other side. The two assemblies look the same but if you use a later assembly in an early transmission the gear will be too far away to be driven. People either cut a new slot or swap just the plastic gear. Found a picture on the inter-web. Post #3. Matching Speedo Gears after Rear End Swap - 620 - Ratsun Forums

The AAR gets its power from the same circuit as the fuel pump. Has your fuel pump relay been messed with at all? Is the pump still on the relay. I've found also that the AAR hose interferes with the AAR plug. It's not really a very good design. You might find that the plug is just not seated correctly. Of course a meter would tell if the plug has power, but it will only have power when the fuel pump relay is active (engine running or AFM open and key on). Glad it was the easy fix (so far). Good luck.

I hit 62 degrees at my house today. Sun, light breeze, garage door open, birds singing. Don't give up hope.

In your other thread you gave the impression that the play was around the dowel pin, not the center bolt, or camshaft center. Now it looks like the problem is centering the sprocket itself on the camshaft. Is that it? You shouldn't have any orbit of the timing chain gear around the camshaft center, elliptical or not. Could you have the wrong side of the sprocket to the camshaft? Will it flip around? It might also be that the washer under the bolt does some centering. Is the washer there? I have a head, camshaft, and sprocket in the garage. Someone may already know the answer before I get a chance to look at it. Edit - Went out and pulled those spare parts out. My sprocket is an interference or maybe a zero clearance fit on the nose of the camshaft. There's a locating ring on the sprocket and a stepped "nose" on the camshaft. I would get perfect centering even without the dowel pin. I had to use the washer and bolt to pull the sprocket back on to the camshaft nose. It seems possible to think that the recession in the sprocket is for the bolt head to sit in but that's not the case. Maybe you're installing the sprocket backwards? I also checked my spray bar, and it has two trapezoidal shaped gaskets under the mounting points. Pretty sure it's factory stock. Edit 2 - Found a link to a thread that shows what the sprocket should look like before the bolt and washers are placed. You can see that the locating ring/recession is on the other side. http://www.classiczcars.com/forums/engine-drivetrain-s30/35670-timing-chain-install-pics.html

Search "bspt adapter" on McMaster Carr and you'll find some options. You'll have to click through some parts to get details though and do some work to figure out what the gauge needs. I have some out in the garage, I'll get the part number if I get a chance. I found the number from my old internet order. It's little bit long so raises the risk of being broken off if banged. But it has the right threads. Another option is the 3/4" close nipple, 5832T111. 5832T121 BSPT-to-NPT Threaded Brass Pipe Nipple, 1/8" Pipe Size, 1-1/2" L, Threaded Both Ends, Schedule 40

You know that you won't really feel comfortable until you get a good number from a good gauge. You could pull the sender temporarily and install a mechanical gauge just to know what you're really getting. Or you could buy some fittings and plumb a gauge in permanently, and keep the sender (that's what my engine came with from a PO). Even if you get a sender that gives a high reading how do you know it's not erroneously high? False sense of security and all that. The main issue with plumbing a gauge in is that the thread in the block is BSPT. An odd British standard.

SU is showing another possibility, which would actually be generally useful. A reflective surface somewhere on the fenderwell. I use a mirror quite often to look around under the manifold and various other places. It would be nice to have something permanently in place. You could even go further and point some LEDs up under there. Call it a maintenance inspection tool.

Don't forget that many of the ceramic coatings burn off over time. Lots of gimmicky stuff out there. You could go with transparent aluminum. I saw it on Star Trek. Or glass with a low E reflective coating.

Once you get used to using a meter you'll feel exposed without it. It's a good feeling to get the proper reading on a circuit and it's a good feeling to get the wrong reading, before you connect things and cause damage. On the fusible links, I think that 1975 only had one set of two links, and that's probably why the headlights don't work. The fusible link blew from a separate short, probably while working on the regulator plug, and took the headlight circuit with it. Another set of two links were added in 1976, most likely to avoid this issue. The fusible links came with a white plastic cover from the factory. Yours is missing. You'll be able to check the links with the meter also.

No offense intended. It's always a good idea to check your work with a meter. Sometimes what you think is brown is actually red or blue is green. Or you miss the stripe on the back of the wire.

There are many threads out there about the mysterious missing wire, from about 1972 Z's up 1975 (now, in this thread). Nissan changed something in the cars but didn't change the documentation. Shouldn't all of the wires needed be in the same spot as when he started? He had an external regulator connected. If he still has the connectors he could tape them back together for a visual and start over. Probably the best route since he's completely lost now. He really shouldn't be looking anywhere else in the engine bay except for where the external VR was. Also, I haven't seen any signs of meter usage. Even a $5 Harbor Freight meter would be worth getting. You can't do these things right by wire color alone.

I think that you would, for the injector notches in the intake ports, and the bolt holes for the intake manifold. But it might not be a bad combination. The combustion chamber is a little bit smaller than an E88 head, 39 cc versus 42, so the CR would be bumped up to about 9:1. It might also have a larger exhaust valve. But it will have a Maxima camshaft, which is probably not as performance-oriented. Could be worth doing but you'll end up with EFI problems instead of carb problems. If you go EFI it might worth grabbing the Maxima electric fuel pump too, if it's still external. Seems like a lot of work for not much benefit and many potential pitfalls, unless you want EFI. Probably the best head to use though if you want to swap carbs for EFI on an L26 block.

Well, back to your first post - I would focus on extra air, wherever it's coming from. The ECU can add or subtract fuel but without air there won't be a significant effect on RPM. And I would still pinch the AAR line to see if the idle drops when it's at 2000 RPM. Then you'll know for sure that the AAR is closed. The AAR itself might be new but the electrical system could be a problem. The AAR's internal heater is more important than the heating block underneath it.

The BCDD is full of passages, some of which enter the intake manifold. You could plug that line and see what happens.

The 79 FSM says there's a valve, but it's on top of the intake manifold, not in the throttle body, connected to the coolant block (probably the one under the AAR). The thermal vacuum valve. Thermal and vacuum! Could be something. Connect to the throttle body by hoses. Might be worth a look, page EC-8. Maybe there's another port waiting to be blocked. The coolant alone takes a really long time to heat up the AAR. I've had my AAR power disconnected and the high idle lasts forever.

There's a lot of "red flag" BS and nonsense in his eBay pitch. We are a professional licensed Datsun Restoration Business. Our parts are backed with a 100% money back satisfaction guarantee. Trust an ebay LICENSED Seller for all your Datsun needs! All engines must be installed by an A.S.E. certified mechanic or other licensed professional shop for warranty to be valid. Buyer responsible of all return shipping cost. SUbject to 10% restocking fee on all returns

I would like for something that lets air past the throttle body or leaks un-metered air in to the manifold. It only takes a little at idle to get a lot of RPM. BCDD was worth a look. Check power to the AAR also. It should be on as soon as the engine starts, causing the internal heater to start closing the valve. Or you could pinch the AAR hose when the idle is high and see if it drops. A few thoughts. If you can isolate it to one area you can focus. I think that the EGR systems also have some temperature actuated devices. EGR is air in to the intake manifold. Supposed to be closed at idle but would cause an idle RPM increase if it opened. Are you running the 76 intake manifold or 79?

A thought that might help clarify - the writeups around the internet about wiring up an internally regulated alternator are just focused on two circuits. The L circuit which energizes the alt. windings and the S circuit which the internal regulator uses to regulate. The other wires are typically just left hanging,and un-needed. If a person wanted to they could probably just unplug the external regulator, leave the wires alone and run a switched wire to L and connect S directly to the battery. But none of this probably matters to the headlight problem. There's no reason for your headlights to have stopped working. It's probably just coincidence and while the car sat the dimmer switch lost contact. Shoot some contact cleaner in to the dimmer switch at the base of the turn signal stalk. Although - you never said that the alternator was actually charging, only that the engine runs. the engine will run from battery power alone. So, what is the ammeter doing while the engine runs?

I think that some of those extra wires are hot. One probably hot all the time (connected to the battery), the other hot when the ignition is on. Better check and insulate. Here's a check that you should do - with everything off, disconnect and reconnect the battery negative post. Look for a spark at the terminal when you connect and listen for a relay click in the cabin. There's a problem with 76 that you may or may not have with 75.

I'm not suggesting that you do the modification in the attached link. But there is a drawing that shows the link. (Two link meanings in one post! - woohoo). I might have the color wrong. Apparently it's the black one, per two posts previous, the FSM drawing. Although black is the high amp link so that doesn't make sense. atlanticz shows black as alternator and ignition relay. So there's confusion. The 75 FSM seems to have mistakes. Either way, worth a check. http://atlanticz.ca/zclub/techtips/fusiblelinks/index.html Edit - black in 75 appears to run many things. They added two more links in 76, splitting the headlights out on to their own. So, overall, my post is only helpful in that it directs you to the FSM. Your 75 would not run if the black link was blown.

Bummer. Dorman probably offers a lifetime replacement on those parts that don't work. If you're in a hurry you could loop a section of heater hose from one nipple to the other. Won't look pretty but you'll have the right materials in the right place.

I've been watching datsunparts llc over the past few years and it seems like the guy is watching his reputation. But the stories from the past are still there so you know that at heart he's just a guy making money any way that he can. As you noted in your other thread, having a free repair or return policy without paying for return shipping is almost worthless on big heavy parts. zcarsource should have checked your bad transmission before they shipped it. Now you're stuck with the problem. I think that datsunparts will be the same risk. Many of the wrecking yards have a full value replacement policy on their parts. You're still stuck removing and trying parts until you get a winner, but you're only out labor and gas money, instead of big shipping costs, if you can find a local yard.

Dorman is an America-based company. Ultimately they are responsible for specifying and controlling product qualities. To hash it over one more time - the off-shore companies just produce to the specs. they're contracted to produce to. This is an American issue entirely. Corporate Info But, all I really wanted to know is what Dorman designed the parts to do. Maybe you're using vacuum line plugs on the cooling system.