Zed Head

I'm pretty sure that the FSM (76 and 78 anyway) says "NEVER take the BCDD apart", replace the whole thing. So it would be surprising if the internals were available. Could be wrong, but that's my memory.

You might have a vacuum leak. When you open the idle screw you're letting more air past the AFM which will add more gas. This counteracts the lean mix that the vacuum leak causes. But all of the extra air leads to a high idle. Does the idle change when you press on the brake pedal? That would be a bad booster, which causes a vacuum leak when the pedal is pressed. The crankcase (this includes the valve cover and all hoses) needs to be completely sealed for the EFI to work right. The oil filler cap, dip stick tube, breather hose from the top of the valve cover, etc. all need to be sealed.

Get a new machinist. He told you it was an L26. Then he told you to get standard L28 pistons. Obviously he didn't even take a measurement or know what the bore size should be. He should have given you a bore size number to work with. Even better, he should have ordered the parts himself. He's wasting your time and money and will probably do a poor job. You could have bought a good running engine for less than $500.

It's possible that you got a bad alternator housing from the store. The remanufacture process is to tear everything down, sand blast the case, then re-assemble with parts that have tested as "pass". They might have missed stripped threads in the housing. A longer bolt, if you can find one, of the same thread size might catch good threads at the bottom of the hole. Or you can run a smaller bolt through the hole with a washer and nut on the other side, temporarily so that you can tighten it and verify your wiring work before returning the alt, or hope for the best and return it for one with good threads. It would be hard to hold the bolt and the alternator while tightening the nut though, with only two hands. The other bolt I was talking about is the one that bolts the bracket to the engine block. The one that the bracket pivots on. Your nightmare continues. On the bright side (for me) I went to Autozone and got an $8.99 Duralast belt, it went on easy and the low squeak-squeak-squeak noise from my old worn belt is gone.

Coincidentally, I just noticed today that my cheapo alternator belt has stretched to the limit of the adjustment slot. $18 for kevlar-reinforced or $5 for another cheapie. Edit - Went out to change the belt and realized that I don't even typically loosen the bottom bolts. Just the two on the adjustment bracket. Loosen two bolts on bracket, insert long screwdriver down between alt and engine block, pry back and tighten outer bolt on bracket. Might not be the best way but it has worked well. Edit 2 = also noticed that the more worn the belt is, the harder it is to get to the outer bolt. It's a pain.

It would look something like this, with jumpers. All the wires you need are on the body harness side. (Can't believe a little Paint file is so big...) Alt Swap Jumpers.bmp

If nobody knows, I'm pretty sure that they're described in the Electrical section of the FSMs, by model - Fed or California. http://www.xenons130.com/reference.html

Can't edit my post for some reason... You can do the alternator swap without cutting any wires. Just make jumpers at the harness plug. If you find out the problem is elsewhere, then you can go back with no damage, if you want to.

You might run in to the brake warning lamp check relay problem. Here is a convoluted novel on the subject that I wrote way back when I did the same swap (start at Post #4, or read #1 - 3 for amusement) - http://www.classiczcars.com/forums/showthread.php?36480-1976-280Z-Alternator-Upgrade-Minor-Issue-Battery-Drain

By "starter" I think that she means ignition switch. And the problems with the door sound like something came loose in the door linkages to window and lock. The power steering pump shouldn't be too hard to fix, but I've not owned a ZX so can't say for sure. Nothing looks too hard to repair, but it's mostly mechanical, not electronical. If I was looking for ZX, I would go take this one for a test drive. That is low miles for an L6 engine. Offer a discounted price for as-is, she probably doesn't really want to fix anything anyway.

Have you sat in it and ran through the gears (while making motor noises)? The shift lever boot looks like a later ZX boot, not an original 76 style. Maybe it has a 5 speed already? 5th is to the right and up, reverse, right and down.

I got a lot out of this book - http://www.amazon.com/Rebuild-Modify-Transmission-Motorbooks-Workshop/dp/0760320470/ref=sr_1_1?ie=UTF8&qid=1333848551&sr=8-1 How to Rebuild and Modify Your Manual Transmission (Motorbooks Workshop) by Robert Bowen Lots of pictures, of both good and bad parts, with good descriptions. The dog teeth (the pointy triangle shaped things sticking out from the side of the gear) on that gear in the first picture do look worn. The tops of the triangles should be sharp, not rounded. They look abused. And the rust isn't good, that's actually a splined piece that has a matching splined collar that slides back and forth over it. The collar needs to slide easily over that area. The inside of the collar is probably rusted also. It would probably wear off over time, but might be stiff shifting for a while. Just some thoughts. Someone who's actually rebuilt a transmission could tell you more.

While you have the front panel off, you could also adjust your voltmeter. Looks like it's reading high, unless the shot is with the engine running. There's two holes on the back on the back of the meter with adjusting "screws" inside, one of them has an adjustment that will move the "zero" point. I don't know what the other does, it didn't have much effect when I turned it. Set it to 12.6 (eyeball it) with the engine off. You have to turn the screw and plug it back in to see where it's reading. Just a thought, while you're in there.

Maybe BU was thinking of the word digital, versus the word analog. It's not a digital system.

Sorry BU, but that is a little overly pedantic, and incorrect. The injectors are fired by transistors as is the coil. So, by strict, detailed definition, the L-Jet is "electronic." As I understand the definitions...

My 76 does that. It got worse as I advanced the timing for a little more performance. It was also worse with my old N42/N42 engine which had a fair amount of blowby, and worn valve seals, probably leading to a little bit lower intake vacuum when cold. Also, the engines with dual pickups in the distributor run advanced timing when cold, maybe to keep the idle up, or for emissions (but it would still keep the idle up - 6 degrees of extra timing advance when cold). I only have one pickup now, but if you have two, getting the water temp switch to work with your ignition module like it was designed to will help. With a better N42/N47 engine my idle still drops way down when cold, but manages to keep running. And I'm fairly certain that everything is working correctly. One work-around is to bump the idle up to 900 - 1000 to get further from stall RPM. Edit - forgot to ask for curiosity, but are you running flat top pistons with that N47 head?

The symptoms don't really match the solution, but if the timing is correct, you might as well drive it as-is until you have some reason to drop the oil pump. It won't hurt anything, and the odds of breaking something while trying to fix something will be reduced. Hopefully your mechanic set the timing with a light and not by ear when he "fixed" it.

So, back to the OP's question then, as long as the right rotor is paired with the right hub, no discernible change in performance. 280 rotor with 280 hub or 240 with 240. And if does take them apart, all he needs to do is confirm that the offset is right when reassembled, which would be the measurement from wheel face to bearing race. Is this for the early 240s or all of them? I'm surprised that the carpartsmanual calls out the same part number for both, hub and rotor. The parts "bible" is wrong?

That's interesting information. I was under the impression that the S30 wheel base was the same from 240 to 280. You're suggesting that they're different, unless Nissan used different rim offsets, to offset the hub offset. Interesting stuff, especially since the 240s have problems with half-shaft binding when the R200 is installed. i would get some numbers myself if I was at the right computer. Eidt - I have some 78 280Z hubs and rotors sitting in my garage. I could measure hub thickness from inner bearing race edge to wheel mounting surface Thursday night or Friday morning. If someone has a 240 hub we could get a comparison.

It could just be mechanical, not electrical. I had one that would not drop below 2,000 when it got warm but would drop to normal when it cooled off.

What markings are on the injectors you have, and what color are they? I get the impression that some injector companies ID their injectors by color, not marking. My BWD injectors just have RAM molded in to the part, but I don't know if it means anything.

ZX? Looks like a BCDD. No reason for fuel to come out of the hose though.

When you said they took it apart and had the parts in a box, I was thinking of the assembled gears on the adapter plate and the front and back cases, along with a few odd parts. Didn't realize that they would tear it all the way down, taking gears and bearings off of the shafts. Most of what I've read suggests that it's a bad idea to reuse a bearing once you use a puller on it, because it puts high side loads on the ball bearings when they're not rolling, damaging the race and the ball. If that's true, then Aamco knew they had done some damage and was going to put it back together anyway. They should have been able to give you a rough idea without removing the gears and bearings. I think that you might be stuck now, needing a rebuild of at least bearings and probably a little polishing on the gear cones if they do have rust on them (I've read that it can be done). I'm not sure that putting the old bearings and gears back on and running it would be a good idea. I could be wrong. The $131 might still be a decent price for a teardown, if you can get a rebuilder to discount that portion of a rebuild. Now you've got a bunch of choices. Good luck. Edit - One more thought - before you spend more money and time, you might be happier, in the long run, sourcing a late 80 - 83 5 speed, with the close ratio 1-4 gear set. The 77 has the big 2-3 jump and is not the best transmission to rebuild anyway. 80 - 83 has a better reverse lockout also.

I believe that they call this necro-posting. But, at least it completes the thread (dead) for future searchers.

Looks like they're all the same - http://www.carpartsmanual.com/datsunS30/DatsunZIndex/Axle/FrontAxle/tabid/1728/Default.aspx