FastWoman

I'm not saying there's any regulation with respect to atmospheric pressure. However, there's a fuel leak, and the magnitude of the leak would depend on the pressure of the fuel with regard to atmospheric pressure. That is, after all, the path of the leaking fuel. Terence, I haven't a clue what might be the problem. Can you isolate the problem to specific cylinders? Try unplugging your plug wires, one by one. If you unplug one and find it doesn't make any difference to the running of the engine, then that cylinder is dead, and you might have a clogged injector. Tip: Grasp the plug wires with a rag to keep from getting zapped. Also listen to the exhaust. Does it have a rhythmic "chug-chug-chug" sound? If so, then it's the same cylinders missing with each revolution. Could be (a) clogged injector(s). If not, then the problem is most likely elsewhere.

Thanks, Jon and Tom. Jon, I very much appreciate your taking the time to address the issues I'm seeing, and I apologize if this is becoming a frustrating process. I do feel as though we may be discussing entirely different things. If there's any failure in clarity, it's probably mine. There's nothing like experience with the Z to help a person diagnose a Z. I suppose I should get my Z into the local specialist for an evaluation of the problem. I know at the very least that I need some work on my half shafts, and hopefully that shop can do the work. Used parts do seem available enough, if that's what I need to consider. Anyway, again, I appreciate your endulging me. Thanks, guys! Peace, Sarah

Well, the pressure remains constant WITH RESPECT TO THE INTAKE MANIFOLD PRESSURE/VACUUM. When you suddenly stomp on the pedal, manifold vacuum drops to near-zero, and the fuel pressure rises in compensation -- with respect to the pressure of the surrounding air, that is (i.e. the pressure of the air you're breathing). So yes, there will be a pressure surge when you stomp on the pedal. Of course when the RPMs rise in response, manifold vacuum will be restored, and the fuel pressure will drop again. That said, your fuel pressure will be at its highest (with respect to normal atmospheric pressure) without the engine running, as there is no manifold vacuum. If you don't see any leaks with the engine stopped and the fuel pump running, you're probably just fine.

Mine is young by comparison -- only 160K mi. I'm still rather surprised that the only way to assess backlash is to remove and open up the differential. When one half shaft flange can turn 5 deg while the other half shaft flange and the drive shaft flange remain stationary, that DOES imply something about the total backlash in the gear train, does it not? It might not nail down the exact source of the backlash inside the differential, but doesn't it provide any useful info at all? Hypothetically, if I could just turn one of the flanges around and around while the other two remained stationary, wouldn't that imply something about the internal state of the differential? Would I really need to open the thing up to assess the fact that it's shot? I admit I'm not the expert here, but this really seems to fly in the face of common sense.

It sounds like a lot of corrosion and crust. Your headlight switch takes a lot of abuse from the high current, so it might be feeling it right now. If you get your headlight switch cleaned up a bit, you can install headlight relays, which are gentler on the switch and which will give you brighter lights. I'm not laying all this on the headlight switch. You probably have crusty/corroded contacts throughout your car.

Jan, many of Nissan's parts were VERY standard from model to model and year to year. I'm guessing the carbon canister might be one such part. If you can find one at a junk yard that's the same physical size and that will mount in the bracket, it should work pretty much the same. You might even get lucky and find the same snap lid doodad.

MEZZZ, Jim is right about ventillating the garage, but he's a bit amiss about the real hazard. Having once had an engine catch fire in the garage, I can assure you it wasn't the car I was most concerned about, even though it was a very nice car. I think my home, with all of my belongings, would have been the bigger loss. The lesson: If there's any question whether you're going to have leaking fuel, do your work outside of your garage.

Ah, now I get it. OK, I wasn't seeing your photo the right way. There was a shadow there that was throwing me off. That's going to be a tricky space to use for a subwoofer magnet! I'll have to think about that. Anyway, I appreciate the photo and the measurements. Now I know what I'm dealing with.

I had a Z mechanic like that once, CaliCar. Nice guy. He lived in the country and worked out of a shed. I wish I still had the mechanic who did the prettier work on my Mustang. He's in another state, though, and American cars were much more his thing. The previous owner of my car mounted a pair of speakers in the doors. Of course there was cutting involved. He cut a couple of MDF rings, maybe 3/4 - 1" thick, that he used to offset the speakers, so that he could drop the magnets into the holes he cut. Finally, he covered the rings in black vinyl to match the inner door panel. The reason he used MDF, I suppose, was that he could easily sculpt it to fit the irregular contour of the door. I would think that would be possible with plywood too, using a belt sander to shape it. Anyway, it was a relatively neat and inconspicuous installation (inconspicuous because it's all black). I'll post a photo if you would like to see it.

Thanks, 260zCaliCar! That helps me a lot. (The compartments are smaller than I had remembered.) If I might ask for another favor, what is the distance from the rear-most edge of the compartment to the sloping bottom below, measured perpendicularly to the deck? I'm wondering how far down I can drop a speaker magnet. Tomo, I also like the idea of hinging the front of the deck panel to recapture the area for storage. You don't happen to have any photos, do you? Thanks, guys! Peace, Sarah

Thanks, Andy. All of what I've described is under only mild torque on the wheel. I have the car in gear and rotate the jacked up wheel from extent to extent, until it locks up. As I rotate the wheel back and forth, I don't see any movement in my drive shaft (which would require slop in the transmission). The "inch" of movement I'm describing is from the drive shaft flange and one of the half shaft flanges being held stationary and the other half shaft flange rotating approx 5 deg under very mild torque (until I hear/feel the gears go "clunk"). The half inch (perhaps 2.5 deg) of rotation is from one of the U-joints that's well beyond shot. I'm probably not applying enough torque to reveal slop elsewhere, although I'm sure it exists. I honestly don't know whether the soft whine is there in neutral. I'll find out on my next trip out. Thanks for the tip! I think I'd find out a lot about the transmission if I could only get the oil drain plugs undone. I think they must be super-glued in place. Oof!

Fletch! Cool! Then there IS a bit of room in there. (I couldn't remember, because it's been easily 25 years since I've seen one of those compartments.) So can I ask you a favor? I can't really measure/examine mine without pulling out my hatch floor. Perhaps you could eyeball the compartments for me? Do they look large enough that I could drop the magnet of maybe a 10" subwoofer through them, if the mounting surface is maybe 3" above the metal deck? Perhaps just an 8" sub? If this is within the real of possibility, then I might start disassembling the thing to see how I can do it. Unfortunately it's not as easy as simply pulling back the carpet and detaching the false floor. My car is a bit more involved than that, owing to the stereo installation.

FAIW, if you have a 1978, there's room under your hatch floor. Lift up the spare tire door, and you'll see it. You might be able to mount some of your equipment up under there, provided it doesn't require too much ventillation. I also agree with 260zCaliCar. The retro unit wouldn't give you the CD, but it shouldn't sound too bad at 64x4. There are some OK speakers that will mount up in the original mounting locations. If you don't mind one very minor mod, you can mount a CD changer neatly behind the passenger seat. Another possibility is to forget the CD, and install a jack for an iPod or somesuch. FAIW, I don't think the vintage car specialists NECESSARILY care more about your vintage car than anyone else. I've had very mixed luck with my '66 Mustang, for instance. One independent mechanic did some very beautiful retrofit work on my cooling and brake systems. I didn't ask him to be beautiful in his work. He simply cared enough not to slop up a very nice car. Another mechanic who fixed an electrical problem for me did some incredibly sloppy work and didn't even fix the problem correctly. I didn't complain, because I was simply "giving" him some work to do, so that he would house my car in a safe garage during a hurricane. The safe harbor was well worth the repair bill. Finally, a professional Vintage Air installer retrofitted the car with a 134a A/C system. Now this is someone who works on very nice antique cars all day long, every day, and my particular car has a VERY nice engine compartment. He installed the freon hoses so that they extended upwards in an awkward arch, bumping and rubbing the hood. The duct to the lefthand side vents under the dash was mashed closed over the vent housing and was therefore useless. The useless vent also covered the otherwise very useful access to my fuse panel, as well as the accessory fuse panel I had carefull installed beside it. By forcing the vent into place, he actually broke my accessory fuse panel, and I had to replace it to get my stereo working again. THAT was on a very nice car appraised at $14,000. So in all my experience, only one person besides myself really cared about my little Mustang, and it wasn't the vintage car specialist.

So this was a dumb question? Jmortensen was kind enough to provide a bit of useful info for me in another thread, but with more information from me (in this thread, following a more careful examination of my drive train), perhaps someone would have a better answer for me? I don't have a limited slip differential, BTW. At least there aren't any heat sink fins on the case. Just a plain R200. If anyone has any notion of whether this amount of play is excessive, I'd very much appreciate the insights. Thanks! Sarah

Kinda bad not getting a reply. I'll give it a go, although I'm sure many of the 48 people who have read your thread would have a better idea than I do. So you've got a fuel injected engine. The fuel pump keeps the fuel and crud moving around pretty well. I'm guessing that there would be very little (if any) crud in your lines, and that it would have been trapped in your fuel filter. There may also be a screen for large crud in the suction side of your fuel pump, but I don't know this. Other than that, I would think your lines would all be clean of crud (rust, sediment, etc.). Varnish might be another matter. However, if you run a couple of tanks with Chemtool B-12 mixed in, your varnish will probably dissolve out. Peace, Sarah

Thanks, Five! I held off on responding, in hope that more responses would come in. I think my responding with "thanks" sort of caps the end of the thread, so I'm not likely to hear anything else. Anyway, I appreciate your responding. I really like the idea of using the spare tire well as a mold for a fiberglass enclosure. Pretty slick! Even so, I want a spare and emergency tools. What do you do for a protective grill over the subwoofer? Do you use heavy screen (e.g. the 1/2" galvanized stuff) attached to the MDF? Perhaps expanded metal? I would need the grill to hold up underneath grocery sacks and an occasional 20 lb dog. The way the '78 hatch is constructed, there is a false fiberboard floor a few inches above the metal floor. I'm thinking of removing the fiberboard and constructing a subwoofer box in its place, raised to the same level as the remainder of the hatch floor. (The rear fiberboard door would be hinged to it.) The speaker cones and frames would actually be housed above the sheet metal floor, and the magnets would drop into the two holes. I admit it's not the optimal shape for a subwoofer housing, but low frequency sound would diffract pretty easily inside a weirdly shaped enclosure. I wouldn't end up with a powerhouse of a subwoofer, but then again, my objective isn't to roll down the road blasting folks with dish-rattling infrasound. Jazz is more my style. I just need a healthy bass response to balance out the lower end of the spectrum. With an in-floor subwoofer, I could then take out the huge subwoofer system that's sitting in the rear of the hatch and free up a lot of good space, as well as having a cleaner looking hatch area. Anyway, I was just curious how people have used these storage compartments and especially whether anyone has housed speakers in them. I guess nobody else on this list has any thoughts as to how they might be used. Of course I admit they ARE rather buried and difficult to use. Thanks again for describing your spare compartment subwoofer! Very nice!

Just another thing to consider: Rolling down the freeway with your window open creates a lot of drag. Running with the A/C can actually save you fuel. You might even save enough to pay for the repairs, depending on how much you drive your Z.

There are different lines of thought with regard to originality. There are the mint-condition, factory original cars with all the original stickers, original types of tires, original wheels and caps, and maybe even a factory original battery without the battery acid in it. These cars are a beauty to behold and are often quite valuable. However, you can't actually *drive* them or enjoy them the same way you would an ordinary car. An aftermarket stereo in such a car would destroy much of its value. Then there are the cars that the remaining 99.5% of us own. If it's a nice car, don't go cutting holes in your sheet metal, and make sure you can put everthing back to original if necessary, but yes, do go for a stereo you like. Everyone else does, and it won't really hurt the value. If it's not a particularly nice car, do whatever makes you happy. As for cost? It all depends on what you want. I'd be careful of professional installers, though. They often do rather "meatball" work. They won't love your car the same way you do.

Your fusible link wouldn't have been blown out by the jump start. It probably wouldn't have been taken down by a shorted solenoid, and no other starter problem would have done it. I'm guessing the culprit was corrosion. I first learned what a fusible link was when a link in my '75 Z corroded through at a mere 8 years of age (i.e. 1983) -- in TEXAS! It left me stranded in the center turn lane of a highway, and I had to be towed. The fusible links in my recently acquired '78 didn't fail, but they looked incredibly crusty, and one of them fell apart when I unplugged it. (I did pull by the connector, not the wire.) The fusible links would be the same between the 240, 260, 280, or any automobile, provided they have the correct rating. (They come in all different ratings, just like normal fuses.)

Assuming the battery has voltage, the fact that your lights aren't working would suggest you have a fusible link problem. I don't know whether the lights and the ignition key circuit share a fusible link in the 260, but if so, then I think that might be it. Try bypassing your fusible link(s) and ignition switch: Just clip a small wire to your starter's solenoid terminal, and touch it to the + post of your battery. The solenoid should close, and your starter should crank. If it will do this with the jumper wire but won't do anything when you try to start normally with the key, then you have an open circuit somewhere. It could be one of several things, including a fusible link, the ignition switch, or the connection to starter solenoid (i.e. small wire). If the engine doesn't crank with the above test, then it's either your battery, your starter (not likely), or your battery cables. To narrow down a bit: Try charging up your battery with a charger. If/when it shows it's been charged, test it with a volt meter. If you have maybe 13V, you're good. Even if you only have 12.25V or so, you have enough charge in your battery to test it. Now have a friend turn the key, while you continue to read the voltage. The starter solenoid should click if you have 12+ volts. If not, there's some problem with the solenoid or with the wiring or connections to the solenoid. If it clicks, then your starter should be engaged. Does your voltage drop to approx nothing? If so, then your battery is probably bad. Another test would be to turn on your headlights. (I know you say they don't work.) When you do this, does the voltage drop to almost nothing? If so, that's further evidence the battery is bad. Finally, run jumper cables from another vehicle. Now can you work your headlights? If so, the battery is almost certainly bad. If the battery is good, but the starter won't crank, then test your cables. Start with the + cable. Attach the probes of the meter to each end of the cable -- the + probe at the battery and the common or - probe at the starter. Voltage should be zero. Now have a friend turn the key. If the voltage jumps to +12, then your cable is bad. Now hook the probes on the end of the negative (ground cable), with the common probe on the battery end. Repeat the test. A significant reading, higher than maybe a few volts, would indicate a bad cable. (I'm assuming at least SOME conductivity, because we're assuming your solenoid clicks.) Now test your starter. Your starter has a big terminal where the battery cable connects, and it might have another large terminal where the solenoid couples power into the starter. If so, attach the probes to these two terminals, with the + probe on the battery side. Have a friend turn the key. You'll hear the solenoid click. Do you get 12V across these terminals -- exactly the same as at the battery? If so, your starter has an open circuit (bad). If the voltage is high, but less than 12V (which it should be), then the engine should be cranking. If the voltage is zero-ish, you might have a shorted starter. Finally, you can take your battery and your starter to an auto parts store to have them tested. That might provide you some better answers. Good luck! :-)

Hi Mike, Sorry you didn't make it to the wedding. It could well be that you have multiple fusible link problems. The best way to know they're all conducting is to get a multimeter (or volt meter) from Radio Shack or the hardware store. They're incredibly cheap these days -- maybe even $5. (I once found a bunch of them on sale for $5 and stationed them in the emergency kits for all our cars and boats.) Anyway, touch the negative probe to the negative post on the battery, and touch the positive probe to each connector on each fusible link (i.e. 8 readings total). Poke at the connector pretty hard, so as to make good electrical contact. All the terminals should read the same as the voltage at the + terminal on the battery (ideally 12.5V or higher). If you find a fusible link that reads +12 on one side and zero on the other, the link is bad. Regarding your half-charged state... Did the volt meter read 12.25V (the half-charged voltage for a lead-acid battery), or was it 8V (half of the 16V full scale)? If it was 8V, your battery was quite dead and wouldn't have turned your engine. Even 10V usually doesn't turn an engine. If the voltage falls below 12V, you're better off not trying to crank the engine, as you can really destroy your battery. Anyway, good luck with your Z, whenever you get a chance to work on it again. Don't let it sit too long, or your problems will multiply in a hurry.

If your wiring harnesses are hopeless, I believe you can replace them with reproduction harnesses. A factory service manual is going to be your best friend, if you don't already have one.

The little compressors are the best thing to carry. I once used one of those flat-fix cans and ended up rusting out my steel rim. I have no idea if they're as corrosive on aluminum. A tire guy shook his finger at me and told me never, ever to use one of those again.

I didn't post this before, because our cars are likely fairly different. However, this is a photo of the underside of the control assembly of a 1978, with red lines drawn where the control cables are attached. Perhaps the clips are similar. One end inserts into a rectangular hole, and the other snaps around the edge of the chassis, pinching the cable into place. I don't know if that helps.

Hi all, I remember my delight when I pulled up the hatch carpet on my old '75 and found a couple of odd-shaped storage compartments in the forward part of the hatch area. The way the carpet was hinged, the compartments seemed rather useless, so I didn't use them -- and forgot about them. Now with my '78, I've been looking at the hatch area design. Of course I have the false floor (which I've decided should probably stay, after all). Underneath the forward part of the floor are the two storage compartments, without lids. That's a lot of wasted space. I'm also looking at the big subwoofer sitting in the back of my hatch area, and that's a whole lot more wasted space. I'm wondering whether I can build subwoofers into the storage compartments, overlaid with protective waffle grills and carpet. In the case of my '78, I'd be able to build an enclosure that rises to the false floor and simply drop the magnets through the holes, lining the cavity with fiberglass, of course. Has anyone done this? Maybe there's a better way to use this space? Has anyone figured out how to lay/fold/attach the carpeting to actually use these storage bins for storage? Has anyone figured out a good way to do it with the flat raised deck in some of the 77/78 cars? Thanks for your ideas! Peace, Sarah