Captain Obvious

Many manufactures did that printing on a clear plastic scheme. Then they backlight the gauge and the light passes through the silk screened plastic. Trying to redesign the Z to use such a scheme, however, would be darn near impossible. As for where to get PWM controllers, you would need to ask enough questions or read enough documentation to determine if they are high side or low side controllers. Not easy to do.

Haha!! Not my fault! You guys saw ME, right? I think the distraction was at the pool, not at the bar!

Well thanks for stopping me before I started. I had been toying with the same idea of covering my interior plastic panels with vinyl, and the troubles you describe have given me second thoughts. It seems you've got way more experience with this sort of work than I have, and if it's giving you issues, then I can only imagine what would happen if I were to try. It likely wouldn't be pretty at all. If you come up with an alternative more stretchy forgiving material, or a foolproof "for dummies" method of working with what you purchased, that would be great. But if not... I think I might be shelving this project.

jonathanrussell, Where there any manufacturers part numbers printed on that tape you bought off Amazon? When I redid my harness, I used Elliott Tape EE 201, which is dry (no adhesive at all). It sticks to itself very well, but I think the original tape from Datsun did have a small amount of adhesive on it.

Yeah, that would be really bad for that thing to stick while driving. You might not even know about it until it's too late. What kind of fuel filter are you running? The ubiquitous G3, or something different? Seems weird that anything "visible" could make it through a filter like that, even if it was a couple years old. How about a liquid contamination issue maybe? Ethanol in the fuel reacting with the aluminum or the brass inside the pump? Water maybe? Something like that?

Kira, I got your PM and responded!

Calling it "heavy duty" doesn't tell you whether it's a high side or a low side driver. Without seeing it, I suspect that's more about the relative current handling capacity of the device. The small ones I've been messing with are designed for a total current from a couple dash bulbs. If you were to try to dim a three 10W incandescents, you could burn up the insides of the module because it might not be able to deal with that much current. Low side drivers have always been easier to produce because of the fixed reference point (ground) and inherent transistor technology. High side is of course possible, but usually more complicated and more expensive.

All of the automotive PWM dimmers that I've messed with control the lights the same way the original rheostat does... By varying the amount of bulb current to ground. Goes like this: When you turn the lights on. one side of the bulb is connected directly to +12. The other side of the bulb is pulled to ground through the rheostat. The PWM dimmer does the same thing except it pulls to ground with an intermittent connection through a switch (transistor). Of course, I haven't dissected a dimmer from every car ever, but the "low side switching" scheme is easier to accomplish in electronics, and I suspect most of them work that way. Also note that the early Z's operated differently and had the rheostat on the high side of the bulbs. The PWM dimmers I've messed with would not work on those early cars without additional changes to the cars wiring.

I'm no carb expert either, but my read is that the whole purpose of the float and the valve is to keep the level in the bowl constant under all conditions from idle to WOT and every point in between.

Well that's not cool. Did you lay eyes on said sludge gumming up in the pressure regulator? I'd be concerned that without knowing the origin, it could happen again?

Kira, I have a 240 rear overrider bar available, but I don't remember what year it is from. Is there any identifying measurements you can convey that would help me determine what year it is for? Or, as an alternative... Could you identify it simply from a photograph? Cause I could certainly do that.

OK, fine. If the flow rate into the bowl was higher than the rate exiting, it would overflow out the tube into the air cleaner. How'd I do?

They changed the bulb style for the littlest bulb over the years, but I don't think there are BA7's in your year. They used a smaller (smaller than BA9S anyway) bulb in things like the hazard switch, fasten seat belt warning, and defroster switch. But in 77 they used a T-1-3/4 globe glass wedge base, not a bayonet base. I didn't look into the earlier bulb style in earnest, but in 74 they used a different base for those small bulbs. So the earlier cars may use a BA7S, but the later cars don't. I don't know when the transition to the wedge base occurred, but you're after it. For posterity, my 77 original bulbs for smaller indicators like fasten seat belt, hazard, defroster was a TSD 74 - Glass Wedge Base, T-1-3/4 globe - 14.0 Volt 0.10 Amp 1.4 Watt

Haha! Nice. You really want to pull all the fuses out of that fuseblock anyway and clean up all the electrical contacting surfaces. I'd replace the fuses with new ones as well even if the old ones still conduct. Most of my filaments were saggy. I've been told that in a couple years it will be more than my filaments, but for now, we'll go with that.

Snake Plissken huh? I head of you. It looks like Solex has a number of different products. Is there something specific you were asking about?

Yeah, I figured, but I had to ask. So one more far fetched possibility... In the old days they used to put a small hole in the chassis of stuff like that to adjust the clock. I guess there's a tiny chance that you've got something like that? Maybe covered by a sticker? And lastly, have you talked to Retro about the issue? There's no way you should be off by 10 min/week. There's a problem there that should have been caught in production testing.

Bummer. It looks like they must have recently added that ON/OFF feature between when you purchased yours and now. Looks like yours just skips right over that one. I took another look at the current manual, and I couldn't find a copyright date on it, but it must be a newer version with some updates. I guess one last thing would be to actually look for that feature on your radio (if you haven't already) in the slim hopes that it's a documentation issue and that feature actually IS in there, but isn't mentioned in the manual? I'm thinking you already tried that, but it's my duty to ask.

Do you mean that you can't figure out how they are supposed to be positioned, or you can't figure out how to hold stuff while you twist it during the assembly process?

I'm putting in more resistance in addition to what was originally in there, so I'm actually significantly under-driving the LED's. Remember... I'm trying to decrease brightness. I'm thinking that I should never ever have to go back in there again. Not for about 50K hours anyway. My soldering technique is better than the kid in China that put them together the first time and I used enough glue to assure they won't easily twist apart like they did originally.

I'm not sure about the very early cars, but in general, here is what is dimmable: Gauges (speedo, tach, temp/oil, volt/amp/fuel, clock) HVAC panel Radio faceplate Hazard switch green indicator And the gear shift position for the auto trans if so equipped. All the other things including cigarette lighter, glove box, ash tray, map light, high beam and turn signals, etc are non-dimmable and run full brightness at all times. If you leave at least one incandescent in the circuit, you'll get some dimming function even with the original rheostat, and the easiest one to forget about is the hazard switch.

And as for putting a kit together... You know you won't get good brightness control unless you upgrade to a pulse width dimmer too, right? If you use the LED's with the original rheostat, you'll be pretty much full bright all the time.

TomoHawk, Those 5730 or 5050 number designations for the LED emitters are a "series number" relating to physical size. The numbers are in millimeters with an assumed decimal point. For example, 5050 is a square outline package that measures 5.0 by 5.0 mm on the sides. Other example, 5730 is a rectangular package that measures 5.7 mm by 3.0 mm on the sides. Those numbers don't tell you anything else like color, hue, manufacturer, brightness... Just size. Consumer packaged LED technology is moving very quickly right now, and everything is volatile. In fact, that may be why there aren't as many of those eight emitter paddlewheels on ebay. It's volatile.

So I got my car put back together and did some night time driving for the first time this season and got to try out my new pulse width dimmer and dash LED's. I'm thrilled with the results of how the job turned out. I know it's really hard to describe with words how bright the LED's are now, but I would say... "They are a little brighter than the original incandescents turned all the way up, but they are a purer white than the originals." Here's the LED bulbs that I used. Six on the left with the top emitter removed and a 240 Ohm resistor built into the base. These are for everything other than the clock. The clock wanted a little more brightness due to the construction of the clock and the way the light has more internal obstructions before it gets to the face. Because of that, I used a 150 Ohm resistor for the clock emitter. And the wedge base paddlewheel on the right was for the HVAC panel. I shorted out all the original resistors an inserted a 1K Ohm resistor in series with the whole device. For that one, I broke the original ground side connection and inserted the resistor there. All of them are warm white, and here they are all done and glued back together ready for install: And here's a closeup of the paddlewheel for the HVAC trying to show how I inserted the 1k:

TomoHawk, I can't believe those paddlewheels aren't on ebay. I thought they were everywhere! I like a good pun and all, but that's just sad. ?

hansonsaid, Awesome. I haven't had to touch mine since I put it all together. Works great. Did you get the Audi hose new, or from a junkyard?