Captain Obvious

I've found the easiest way to change those little bulbs is to: 1) Put on a rubber glove on hand because the rubber provides better friction to the glass globe. 2) Pull back on the center wire a little to compress the spring inside the socket. 3) Once you're not fighting the spring anymore, turn the bulb with your gloved fingers. Once you get the hang of it, it's really pretty easy. Don't try to push the bulb in to compress the spring and try to turn it at the same time. It's much easier to compress the spring with the other hand. Works great for insertion as well as removal.

And one other thought about leaving an incandescent in the system. I suspect the people who have replaced their dash gauge bulbs with LED lighting have done just that... Either by accident, or on purpose, I suspect they have left a bulb or two (or more) as incandescents. Depending on year and options, some possible culprits include: HAZARD switch, cigarette lighter, HVAC faceplate, A/T shifter bezel, original radio. If you got a 260 with an auto trans, you could leave FIVE incandescents in the system and still have LED's in all your gauges.

I was asking about mods like a headlight relay upgrade because if you would have done that mod, you would probably have an unused wire going through the grommet on the passenger side that could have been re-purposed for your fan override. Independent of your fan controls though. Yes, I would recommend a headlight relay upgrade. The original switching system is overtaxed by the headlight current and I'm continually surprised they didn't use relays in the original design. They used a relay for the fricken horns, but they didn't use any for the headlights??? You've got a 78 right? Already has an internally regulated alternator.... Just musing ideas.

Kurbycar, Yes, LED's can be dimmed just fine using a regular potentiometer, but there's a catch... The catch is that the potentiometer must be of an appropriate value sized for the current going through it, and the stock dimmer pot is not of appropriate value for LED's. Goes like this... The stock dimmer pot is adjustable from 0 to 10 Ohms. When it's cranked to 0 ohms, you get full brightness. No problem. Problem comes into play when you crank to full dim... You're putting a 10 Ohm resistor in series with the LED (or LED's if it's a bulk string) and they could care less. The LED's draw so little current that there's very little voltage dropped across the 10 Ohm pot and the LED's still light up at near full brightness. If you include one incandescent bulb somewhere (or a low value resistor instead) wired in parallel with the LED's, that one incandescent bulb will provide a low impedance path around the LED's and allow significantly more current to pass through the 10 Ohm pot. The additional current through the pot will increase the voltage drop across it and the LED's will have less voltage to work with. You probably still won't get full brightness range, but at least you'll get more range than you would without the bulb. If you really want full brightness range, you need to switch to a higher pot value (probably on the order of a couple hundred Ohms) or switch to a PWM type dimmer. http://www.classiczcars.com/topic/52446-pulse-width-modulated-pwm-dimmer-control-upgrade/

I think there are only two electrical grommets that go through the bulkhead wall. The big one on the driver's side (for the EFI) and the big one on the passenger side (for everything else). I'll take a look at the wiring diagram and see if I can come up with any bright ideas on a wire you could repurpose. This is for a wire that goes hot when you hit your override switch, right? Connects to green on your control relay? You done any other mods like a headlight relay upgrade?

T-handle looks great, but somehow the thought of grabbing ahold of two pounds of sub-zero stainless steel on a frigid Canadian winter morning just doesn't do it for me. Sounds too much like a tongue on the flagpole. To each his own though. I certainly owe you! I can cut them a tiny bit tight and you can lap to perfect fit? Shoot me a PM.

Cool. Sounds like you found good stuff in the glove box! So another crisis averted, Bring it up again if you need additional input.

A couple thoughts... First, If the Z transmission is like others I've been into, you're less likely to hear any gear whine in fourth gear because it's a straight shot through the gearbox without going through any of the counter-gearing. Because of that, none of of the internal gears are actually under any load. They're just along for a no-load spin in the oil. All of the power goes in the input end, straight through a locked up main shaft, and then out the output end. Second, I've noticed that a LOT of transmission noise is transmitted through the shift knob design. I've messed with a couple different knob designs and I've found the quietest versions are solid, heavy, and have all parts either completely firmly mounted, or shock mounted in some sort of elastomeric adhesive (fancy words for "RTV"). Third, I made shifter bushings out of Delrin. Doesn't add anything to the discussion, but just because I can. They turned out awesome:

Haha! I just hope the next owner of my car doesn't consider me "The Typical PO". I suspect it's inevitable, but I can dream, right? Heck... I'd buy a car off of me.

I believe that all LED's are inherently very dimmable. Assuming you don't overheat it, the more current you push through the die, the brighter it gets. Works great from almost no light emission, all the way up to max brightness where you can't dissipate the heat anymore. But in the world of using LED's for "real world applications" like home lighting and automotive lighting, it's not that simple. The problem is that the LED's you purchase for pre-canned applications (like 120VAC home lighting applications or 12V automotive lighting) are more than just a simple LED. They are multi-component assemblies and unless you know what comprises that "assembly" you cannot guarantee how well they will react to a dimming attempt. Some of the assemblies are simply a couple LED's in series with a current limiting resistor. These should gracefully handle an attempt to dim them. But on the other hand, some of the assemblies are much more complicated than that and attempt to account for wider supply voltages and these might not react favorably to an attempt to dim them. Then there's the WAY they're dimmed... The original resistor potentiometer based dimming scheme won't work if you convert ALL your dimmable bulbs to LED. You'll need to keep at least one incandescent bulb in the system somewhere, or switch over to a PWM based dimmer system.

Awesome. I don't know much about racing... Were you in a stock class with (hopefully) similarly performing cars? And as for your wire back into the interior from the engine bay, I don't have any silver bullet for that. Unless there's some function that you have stopped using such that you could repurpose an old wire for a new application, I don't have any great suggestions. Push a wire through the existing grommet?

Yeah, I try to do the same, but I'm not completely diligent. Sometimes when I complete fix or project, I just want to stop thinking about it and don't catch up with the paperwork like I should. So I'm with ya. I pity the next owner of my car. The worst ones for me is opening something up to mess with it and see some marking or writing inside there in MY handwriting clearly indicating that I've been in there before, but don't remember when or why...

Glad you got the glove box open. Now that you can see both sides of the lock, is it clear why the key turns, but doesn't open the door? And Cliff, I'm getting mixed messages from your poster as well... Is the decline in place only WHILE drinking? Because, as you witnessed, I can certainly attest to the validity of that!

One Way, This site is a very valuable resource for me as well and I try to give back when I get the chance. I'm no Z car expert or anything, but I try to help where I can. Stay warm and dry, and here's to hoping you guys get back to normal as soon as possible!

Haha! Yes, Zed Head. It is possible for me to lock the keys in my 77. And I suspect that even as methodical as I am, I will eventually do that someday. Greg, Yup, my 77 came to me with multiple keys as well. One or more of the previous owner's had issues with the locks and had replaced some stuff. I had a different key for EACH door, and a third for the ignition, glove box, and hatch. One of my past projects was to rekey everything back to one key. Hopefully what I've got in there now will last the lifetime (of my ownership) of the car. I don't know when they made the change to one key, but since it's in the 77 Owner's Manual and Zed Head says that his 76 also uses just one key, I don't think there were any 77's that used up old stock. Nobody could really know for sure, but I suspect your car had some work done. Don't lock your key(s) in your car!

Greg, If your 77 works that way, your car probably had the doors and ignition locks replaced at some point. According to the Owner's Manual, your car left the factory with the same key working everything.

Zed Head And just for lock trivia... The 77 and 78 doors can be locked with or without the key. If you push the lock button down before you close the door, you can hold the door handle up while you close the door and it stays locked. If you just close it without holding the handle up, it unlocks itself when it latches. Page 6 of the 77 Owner's Manual describes the single key for everything and the locking procedures. From what you said above, it sounds like this feature started in 77? Yet another reason I love my 77!!

Earlier years used multiple keys, but the later years did not. The later years, like yours, used one key for everything. However, many of the lock components have worn out and have been replaced over the past forty years and there's no guarantee that what you have in your car is original or not. Also keep in mind that the door locks and ignition switch are generally used much more often than the glove box and hatch locks, and hence, usually wear out first. It's conceivable that your car had the doors and ignition lock replaced at some point and that's the key you have in your possession. And there's no guarantee that if something was replaced (like the doors and ignition locks) that they keyed them the same as the car used to be. Probably should have, but no guarantee. All that said... If you're just trying to get into the glove box, you can take the three or four Phillips head screws out of the hinge on the bottom of the glove box door (above the passengers shins) and get the door open a bunch. And once you have it open that far, you might be able to see what's going on with your lock and latch that is making it not open the correct way.

Yup! That's the one! Somewhere near the top is "Today". And somewhere near the bottom is "New owner discovers horn doesn't work and complains about previous owner's shoddy workmanship."

jwtaylor, Yes, a brass screw would be a better choice, but steel is what I had handy at the time. I made sure there was significant meat on the contact above the screw tip though, so I'm not really worried. I'm guessing I should be able to get at least twenty to thirty years out of the contact before I need to check it. I'll put a note in my follow-up folder.

So you've clearly got the welding part down and have used it on busted bolts and the like in the past. Only problem is you didn't know what you were dealing with. Now we both know. And I thank you for the info in case I ever find myself in a similar situation. It's always easier to take the SECOND one apart! My mentors referred to that as the "Brute Force and Ignorance" (BFI) method and I'm quite familiar with that method as well. So one more detail about this stuff... You really only need to get ONE ball out the hard way. Because once you have one side out, you can press the other side out by pushing the pivot pin through the housing. So the job is really only 50% as hard as you might think, right? Haha!! That happens when you get older, right?

Haha! My pleasure. Just remember that I gave a "non-answer" though!! Just anecdote and input from someone not trained in the fuse art. Wish I knew more and could have been more definitive. Still awaiting SteveJ's wading into the fray. Maybe he's got the kung-fu.

My thoughts? I honestly don't know. My questions are: "Is there any functional difference in operation between fuses and fusible links?" and the follow-up question of "When designing in a protection device, what would make you choose a fusible link over a fuse?" I spent a little time looking into the above questions a while ago and about the only thing I could turn up on-line was that fusible links were historically used in applications where fuses were unavailable because of the current capacity. So back in the mid seventies, forty and fifty amp fuses, especially in the glass tube style used in our fuse blocks simply weren't available. But if you look under the hood of cars now, you see cartridge fuses of 100A or even more coming right off the battery terminal. I guess the answer could be that parts like that just simply weren't available back when our cars were designed, and if they were designing them again today, everything would have been fuses instead of of fusible links. However... In engineering, frequently even the seemingly mundane is often much more complicated than it appears to the non-expert. I wouldn't be surprised if an EE from Bussman would be rolling his eyes right now at my lack of understanding.

Careless, I wasn't proposing to push the balls through. I know that won't work because of the step in the id (it's known as a counterbore). I was just musing some ways to PULL the balls out because, by design, pushing them through simply cannot succeed. The suggestion of heat would make it easier to pull the balls OUT if you could get a grip on them. I mean... Yes, there's a slim to zero chance that heating the housing and then rapping it on a hard surface might knock the ball out of the hole in which it's pressed into, but very slim chance. Sure, I'd try it, but I would be more surprised if it would work than if it would fail. And as far as if the balls are hardened or not, just because they didn't deform isn't really a true indication. Again... slim chances that they are NOT hardened, but anything is possible. If the balls are hardened, you might be able to drill through them with a carbide bit, but it's not as easy as it sounds. Other ideas? If I had two pumps, I'm confident I could salvage the arm from one of them and the body casting from another. Then I could put one pump back together using a different (removable) means to hold the arm in place and seal the holes. You might be able to weld a stub to the ball and use the stub to pull the ball out. The heat from welding might also temper the balls to make drilling easier. Temper the balls. Just felt the need to say that again...

Excellent. And I believe your understanding of the way the system works and the wiring involved is spot on. If you wire things up as shown in that manual sheet and take the override circuit green wire hot, the fan will run regardless of key position or sensor temperature. Only other input I would have about the override switch thingie is that they show a 15A fuse in diagram #4 and I believe that is severe overkill. I'd be surprised if a 2A fuse wasn't big enough. I don't know exactly how much current the relay primary coil draws, but I guarantee that 15A is way larger than required there.