NewZed

Non-running is probably less than the Low Retail - http://www.nadaguides.com/default.aspx?LI=1-22-1-5013-0-0-0&l=1&w=22&p=1&f=5014&y=1982&m=1254&d=802&c=13&vi=79166&z=97225&da=-1

I think that your coil should have battery voltage (12 volts) at both + and - terminals when the key is on. The primary winding current flow (in conjunction with the capacitor/condenser) is what energizes the secondary windings. If you have voltage at the + but not at the - then I believe that your coil is not working right. And that's why the - goes to the ignition module. When the current flow to the capacitor side is stopped (points closing or module triggering) the coil sparks. My limited understanding of coils and ignition systems...feel free to shoot me down if I am off-base. p.s. I think that in the past you have mentioned a smoking condenser. The condenser is part of the ignition circuit and needs to be working also. You can test all of the components with a multimeter. Edited at 2:46 - think I had something backwards.

Here's a few links to stores that sell links. What was Br(brown) in the manual and on the fixture labels is now known as red (color fade with age apparently). On the busted connection, it's just electrical. Datsun crimped some of their main power line connections so I don't think that soldering is necessary as long as the fix is protected from the elements. http://www.datsunstore.com/advanced_search_result.php?keywords=fusible&osCsid=95598e23ad3319492fefbe5e6efabfd5&x=0&y=0 http://www.courtesyparts.com/kb_search_result.php?chassis_id=59&keywords=fusible&Submit_Button=Go&cat=1 http://www.thezstore.com/store/merchant.mvc?

Check your master cylinder also. The two tend to go bad around the same time. Also, if you adjusted the pedal while working on it, you might have it too tight. The master cylinder piston has to retract completely to let fluid in to the lines. There are a ton of posts on the various forums about master, slave, "clutch won't work", if you want to get more viewpoints.

http://www.thezstore.com/page/TZS/PROD/12-4067

The booster and master cylinder are model specific. The only input from the engine is suction from a vacuum line. So the one for a 1971 240Z would be correct. 260Zs were made in 1974. 1977 was a 280Z. In the states - I think other countries may have had different models available in different years.

Carb and choke cleaner works great and doesn't leave any residue.

Can't really help you with your decision. But I thought that the N47 did come with injector notches since it is a late model head. Below is a quote by 1 fast Z from a thread on cylinder heads. I have an N42 head on an EFI 76 and an N47 on an EFI 78 myself. Just trying to clarify for you, and make sure I know what I think I know. Even the 75 head should have injector notches. "N42= This head came on all 75-76 and EARLY 77 cars. It has the 47cc chamber, and this head is a fully open head. This head was used on a fully dished piston, to where no quench was used. It has the largest of the valves much like all 280's did. 44mm intake and 38mm ex. This is the last of the L heads that came with bronze seats. This head has Square ex ports, and has the Injector notches as well. N47= This head came on all mid 77 through the 1980 z cars. It has the same exact characteristics as the N42 except that it has the cast in ex liners. These liners were cast in place, for the reason that when the motor is running, these liners get so hot that they glow red hot, and with that you get the advantages of them burning off the hydrocarbons that are left over in the exhaust charge. This is the first head to have hardened seats put in all of the valves." http://forums.hybridz.org/index.php?showtopic=62691

Did you stick your finger in there and see if it comes out with fine gray grit on it? I noticed when I was working on mine that the rod from the fork to the slave cylinder is not in-line with the bore of the cylinder. Close but not perfect. So there is a side load on the piston in the bore, which probably led to the galling. The inexpensive cylinders probably are made of less durable materials. OEM if mine fails again within the next couple of years. I've read that they last longer. Failing slave cylinder stories are all over the internet. I wonder if having the cylinder chromed would help. Might be cheaper than new.

I have seen it recommended, either here or over on classiczcar, that they be taken apart and cleaned before installing, whether from Autozone or Schucks or wherever. I took my last Wagner brand slave cylinder apart before installation and it had about 2 cc's of oil inside with what looked like honing residue in it. It looked like they just pulled it out of the final finishing machine at the factory, threw the piston and seals in and boxed it up. The one before that, that I did not clean, lasted about three weeks. This one is at about three months, after cleaning. The first one lasted nine months. The two that failed had both galled a spot in the cylinder, in the middle of stroke, causing the seal to fail.

bjhines, I went to the S wire focus because HeatRaveR said he had replaced that bad wire and connection and still had the problem. Looks like he has other bad connections. HeatRaveR, congratulations on finding the cause of your problem. You might check the wiring diagram for your car first, to see where the S sire goes, before tearing things apart. There should be one at the back of the FSM. http://www.xenonz31.com/s130/reference.html Careful with those wires or you'll end with a "where's that smoke coming from?" issue next. Like your avatar...

I just fixed some bad FPR and pressure measuring issues on my essentially stock 1976. What do you mean by erratic fuel pressure? Erratic while driving, or while testing the pump and FPR? And what was the initial extremely low pressure that you measured? Numbers help. I now have 25 psi at idle with the vacuum line connected to the FPR and engine running, and 36 psi (the factory test value) with just the fuel pump running (engine off), and the engine runs great. Your 78 has essentially the same engine as my 76.

I agree, that does look like localized overheating. Just suggested corrosion as another possibility since there was rust next to the bubbled insulation. Who knows, maybe it's corrosion-induced overheating? Anyway, the S wire is probably crimped on to one of the wires in the harness going to the fusible links. I would just run a new one to the positive lug on the starter, at least to test it out. That's where I put mine after a swap to an internally regulated alternator and it gives proper charging and a good steady reading on the volt gauge in the car. I had it on the battery terminal for a while and the gauge was kind of jumpy. You can even peel back the rubber on the plug and stick a small male spade end in the back of the S wire connection temporarily if you don't want to cut wires. Just leave the old dead S wire there for a while. You can always dig in to the harness later after you determine for sure what the problem is.

From the end of the white S wire to ground (the body or the battery negative terminal) should read battery voltage minus any connection losses, constantly, key on or off. Don't measure across the end of the wire to the alternator connection, you won't get the right reading. Measure from the wire to ground. By the way, it's possible that if you tried to test your new alternator by disconnecting the battery, or the main charging wire, it may have been damaged. Apparently the alternator circuitry is sensitive. Something to consider. Your bad connections might have damaged something also. Anyway, check that S wire for power from the positive terminal and go from there. If it's bad, run a jumper from S terminal on the alternator to battery to see if your alternator is still good.

The thin blue wire would be the L (Lamp) wire. It supplies power from the battery to the windings in the alternator so that it will start charging immediately. It is .3 V lower because it runs through the Charge light (Lamp) in the dash voltage gauge. The white wire is the S(ense) wire. The other end is probably connected to your starter positive lug or your battery or the fusible links. You could track down the connections and make sure that they're clean or you could run a temporary jumper from S to the battery positive to see if the S wire connections are your problem. Rev the engine over 1500 and see what the stable reading is. If that crud in your first picture is corrosion (you live in the Bay area, I see) and not frying from a short, you might just have more corrosion to clean up.

Where and how are you measuring voltage? As I understand the internally regulated alternator, the S wire (one of the two wires at the little plug) determines how much voltage that the alternator puts out. It tries to hold it at ~14.8 at the S wire. So you could have 14.8 at the end of the S wire (often attached at the battery terminal or the main lug on the starter), but actually higher at the alternator itself, depending on where you have the S wire connected, and the quality of the connections. If you have a dirty connection the alternator will pump out more voltage to get the S wire up to 14.8. Connections at both ends of the S wire need to be good and clean. My limited understanding of the charging system...

Z cars that have sat for a while tend to have the low beam/high beam switch get gummed up. It's in the turn signal lever attachment. Have you tried pulling back on the turn signal lever? It is a toggle switch for high beam to low beam. If the turn signal toggle doesn't switch the lights from high to low, you can try cleaning the switch. I have had success with Deoxit contact cleaner, just spraying it in to the switch itself then working the toggle back and forth. What year and model car are you talking about and how long have you had the problem? No idea what that part is that you're showing.

That is a lot of good information. Thanks for sharing. In the meantime I had a chance to look at the gauge hot and cold and then insert a big bulky inline auto store gauge (of dubious quality also of course) to check against. After a long drive and 15 minutes sitting, the gauge read 32 with fuel flowing, compared to 36 cold in the morning. After cooling off, it matched the 36 that the second gauge measured. Confirming what you've said and what Aeromotive recommended against (using liquid-filled gauges to tune with). It read 38 hot when I was having rich running problems with my 33 year old original FPR so I was probably actually closer to 41-42. It was $18 well-enjoyed for my cheap Jeggies gauge (it doesn't even have a vent that I can find). Now I know something more about gauges in general. At least it gave me another clue that something was wrong with my regulator (the engine runs much better and cleaner with the new FPR). I'll just leave the JEGS gauge on and only look at it cold, until I can upgrade. It seems like a Schrader valve, a high-quality dry gauge and some fittings might be the way to go. The Aeromotive guys responded and said essentially what you said. They also said that the electric gauges were probably the best way to go for a full-time application, since the dry ones are not that durable if used full-time. Thanks again.

Does anyone out there know FPRs and fuel pressure gauges? I have a general question, I'm hoping someone with experience can answer or just comment on the topic. I recently replaced my stock FPR with an Aeromotive 13301 adjustable regulator (maybe overkill for a stock engine but it was $45 on CL), after my gas mileage dropped, my exhaust smelled like gas more than usual and I noticed my fuel pressure was sitting 2 psi higher than normal. I mounted it on the intake manifold and it gets pretty hot. Does anyone know how the Aeromotive regulators hold up to heat? I have a message in to Aeromotive but have not heard back yet. Also, I have an inexpensive (cheap ~$18) liquid-filled JEGS fuel pressure gauge mounted on the fuel rail, in place of the cold start valve. Aeromotive recommends a dry gauge due to accuracy drift with temperature on the liquid-filled gauges. There is also some internet info about cheap gauges falling apart under high heat due to soldered joints, poor materials, etc. Has anyone ever heard of a gauge leaking or falling apart? How about accuracy of the liquid-filled gauges? Are they permanently damaged with heat or just inaccurate when they get hot? The new FPR works great and the gauge makes me feel good, checking pressure occasionally to confirm all is correct, but I have visions of my car burning to the ground if something fails. Thanks for any insights.

Apparently I was off on using the EFI pump for carbs. It is workable. Read this recent post - http://forums.hybridz.org/index.php/topic/86730-78-280-carb-swap/page__pid__889403#entry889403

Your 260 motor should have a mechanical pump, on the front right side of the engine. The 260 cars came with an additional low pressure electric fuel pump, in series with the mechanical pump, but it was added mainly to combat vapor lock problems in hot climates (as I understand it). Some people remove the electric pump and just run the mechanical or vice-versa. You could get your car going with just the mechanical pump, then add the electric later if you decide you need it. It's not necessary though if your mechanical pump works. Your EFI pump is made to run at much higher pressures than an electric pump designed for carbs. You can remove it or just leave it disconnected (don't forget to cover the wire ends or disconnect them from the power source). I don't think it is recommended for use with carbs because of the flow rates and the need to add a fuel pressure regulator to your fuel system. I am no expert but I'm pretty sure the above is correct. As far as the other stuff, of course there's a flywheel, clutch, pressure plate, pilot bushing, etc. plus figuring out which wires you need to get the engine to run and which are now extra. There's probably a write-up out there somewhere on converting from EFI to carbs.

Off topic and wrong poster but maybe important to SmoothZ - those blue fusible links in your pictures(if they are actually fusible links and not just regular wire) don't look quite right. From what I've read (atlanticz), blue is rated at 100 amps, which is probably too high for the circuits they are supposed to be protecting.

You can get Deoxit at Guitar Center... http://www.guitarcenter.com/Default.aspx?source=4WWRWXGT

This might help - read #1 and #21 for sure, plus the other posts have some good info. #6 even tracks back to Hybridz. http://www.classiczcars.com/forums/showthread.php?t=35873&highlight=water+temperature+switch If you meant sensor instead of switch, try this - http://www.thezstore.com/store/merchant.mvc?

It looks like it has square ends. Can't really tell from the picture. If so, it's designed to rotate. Hence my guess...