Captain Obvious

Haha! Well it didn't start as resourcefulness in the traditional sense. I was just trying to get my hands on something quick and cheap. I got lucky mostly. I made the brass insert on my lathe. You might be able to turn the wood on a drill as you mentioned above, but you'd be hard pressed to make the insert. A buddy who does some wood working came over today and I showed him the original and my retro. He wasn't positive, but his guess was that the stock knob is maple and my copy is poplar. He also supports the oil finish thoughts and echoed the tung oil suggestion. Anyone got a block of maple that's itchin to find a new home? Haha! I was born too late. A couple hundred years ago I might have been the village tinker. But to answer your question... In the aftermath of the recent hurricane, I made an exhaust pipe extension for my generator so I could run the generator in the garage without having to keep the garage door open. I cut and soldered a contraption of copper sweat pipe such that I could run the pipe extension under a mostly closed garage door. It was brilliant!! Looked great. Fit great. Worked great. Brilliant I say!! For a few minutes... And that's when I discovered that the exhaust gases coming from a typical generator is way hot enough to desolder copper sweat pipe. I went in the basement to check on the sump pump, and by the time I came back up it had melted the solder and blown itself right off the generator. I wasted a lot of time on that one!! :stupid:

Carl, Hate to break it to ya, but that "metal" retainer on the bottom of the OEM knob is actually chrome plated plastic. I don't know if all of the years are like that, but here's the one I just fixed. This is the plastic insert removed from the OEM wood knob: I made a brass threaded insert to repair this one, so NOW it has metal in it. Prior to this, however, the only metal in the OEM knob was the copper and chrome plating on the plastic. I also made a similar brass insert for my new wooden retro-knob. You can see a little brass in the hole at the base. So now they have metal in them, but from the factory... Nope.

Thanks guys. To be honest, I was not expecting it to turn out as well as it did. I figured that this being my first attempt, and mostly freehand at that, this first one was going to be a test bed disposable. Because of that, I didn't want to spend a lot of money. The only scrap wood I had laying around was cut-offs from pine 2x4s from various projects gone by. So I went to the local Big Box Store and paid $3 for one of these: I'm was never expecting a perfect match to the original, but it looked close enough for a test run. It was light in color, had a nice tight grain like the original, and was large enough that I could take material off to shape it similar to the original. And... It was $3 and I could have it today. I have no idea what kind of wood it actually is, but the structure is pretty similar to the stock knob. I've got the cut off ends that I can use to test finishes. Since I was trying to achieve a shape similar to the original knob, the first thing I did was use the original knob to make a sorta contour gauge to use as a guide for shaping the new knob. Crude, but this is what I came up with: As for finishes, I don't think there's any clear coating on the original. There's probably some stain or oil, but nothing like varnish or shellac. So for my first shot, should I use stain or some kind of oil? I think I've got an ancient can of "Golden Oak" stain in the basement... Wonder what that would do? And here's a shot of boring the recess for the shift map. Just because I like "in action" photos:

I just finished fixing a stripped out shift knob for another Z owner and after messing with his wooden shift knob, I decided that I liked it. While I had his original wooden knob in the shop as an example, I figured I would try my hand at fashioning myself a new knob. Here's a shot of my new knob in process: And here is the trio... My faux leather black plastic, the wooden knob I just made, the original wood knob I just fixed: I'm no woodworker, and know pretty much nothing about finishes, etc. Any woodworkers in the house that can provide some input into stains, finishes, etc? Can anyone tell what type of wood and finish was used on the original? I used some light colored wood with a tight grain, but I don't even know what it was... I'm sure there are woodworkers in our midst!! :bulb:

Mike, That's great news. I love it when a plan comes together! CaptO.

The 74 is supposed to run the fuel pump when the engine RPM's are above 400 and the starter is not engaged. The electric pump shuts off if the engine isn't running. So, to answer your question... If your engine is running (assuming it's running faster than 400 RPM), you should be getting voltage at the fuel pump connector in the wheel well. See EF-6 and EF-7 for more detail.

I see the two tube variety now too. Cool, I didn't see that before. The junkyard AAR I have is the single tube style with the exit hole on the bottom. The only other thing I can add about differences is that the Pathfinder one has a phenolic shutter while the stock AAR has an aluminum shutter. Don't know if they changed to phenolic as a cost reduction or for some sort of performance improvement.

That hose in your pic makes a whole lot more sense. That hose is the coolant input to the front carb. From there, the coolant passes through the front carb - comes out of the front and goes into the rear - passes through the rear carb - comes out of the rear carb and connects back to the hard lines at the brake booster corner of the engine. If you decide to go the 240 carb route, search around this site and the other Z sites. There is lots of good conversion info available. Will probably answer most of your questions. Not all, but most?

TomoHawk, That's too funny... Back when I was messing with AAR's, I grabbed one of those Pathfinder AAR's from a junkyard because I saw that it was held together by screws! I was considering using it on my car, but I decided against it because it's designed for a different intake manifold design. If you look at it, you'll notice that there is only one place to connect a hose instead of two hoses that are used on the Z's AAR. That single hose is the air into the valve. The air OUT of the valve comes out the O-ringed hole in the bottom and passes directly into the intake manifold without using a hose. I'm considering drilling a hole in my intake manifold and adapting that single hose style. Would remove one hose from the system and clean it up just that little bit, but that project is further down on the priority list.

Hi FastWoman, I used a lathe to cut the crimped over lip off and after that lip was removed, the the two halves just fall apart. You could use a file to do the same thing. Wouldn't be as fast or as clean of a cut, but it would work. I usually try to take pics of projects like this just in case, but for whatever reason that I can't remember, I didn't take any of this one. I was probably in a hurry to get it back on the car or something. I've been meaning to take it back off the car and take some pics of it opened up. Maybe this week as the weather isn't Z driving weather anyway, right? So if I don't have to spend the whole next week bailing, I'll take some shots for you. Anyway, I cleaned it out maybe 500 miles ago, and I have no reason to believe it needs it again yet. PS - Glad to see you active... Been wondering where you been. :ninja:

I'm not sure what hose you're talking about. If you're talking about the inch or so diameter hose in my picture here: then I don't have a good explanation for that... There should be nothing in that hose except air. If you've got coolant streaming out of that hose, then you got real issues. There are other hoses in that area that are supposed to have coolant in them, but I removed them from the car with that block off plate. The stock setup has coolant running into the carbs to heat them up, and I disabled that feature as well. Are you sure you're looking at the same hose shown in that pic?

The 77 does not have a separate fuel pump relay. Only the 78's have one of those. On the 75-77, the fuel pump is controlled by one side of the EFI Relay which is located above the driver's left knee. There are two relays in that one box, and one side powers the fuel pump. I think they might refer to that side of the EFI relay is referred to as the fuel pump relay in the EFI section of the manual, but the point is, you will not find a "fuel pump relay" in the car. As for testing it and the fuel pump... Easiest thing I've seen is to pull the small spade lug connector off the starter and then then the key to "START". The starter won't spin because of the wire you pulled off the starter, but the fuel pump should run and you should be able to hear it.

I can cut metric threads. Tell Keith if he doesn't want to risk damaging the parts with a die, I can single point some for him.

Been a while since I looked at one of these so please forgive... I'm going from memory here. There is a tiny slotted head screw with a nut on it. I believe the screw passes through the diaphragm. Under the head of that slotted screw is a small (maybe 1/2 inch diameter?) rubber washer. That washer is the seal that prevents fuel from flowing through the power valve when it's not supposed to. In other words, when the valve is closed, that rubber washer provides the closing seal. I've found that those washers either turn to dust or turn to goo. Probably because of the ethanol added to today's fuel. Basic function of the power valve: Vacuum behind the large diaphragm provides the closing force. The spring behind the diaphragm provides the opening force. The washer under the little slotted screw head does the sealing. In order to test the system without the power valve, you can cut a new round gasket without any of the "functional" holes in it and install it between the power valve and the carb body. Cut yourself a round disk out of gasket material and only put in three holes for the three mounting screws. Let the gasket disk block off the small fuel and vacuum holes. (Does that make sense?) For a more permanent modification, you can make a flat block-off plate. Here's what I did: You might not want to leave it on forever, but it helps narrow down rich running issues. If you completely block off the power valve, then there the only way fuel can get to the engine is through the main jet (or the choke nozzle, but I'm assuming that's not your problem).

Wayne, My pleasure! Honestly I'm the one benefiting greatly from this drawing and I'll do whatever I can to make it better. And no hurry on the next rev. Maybe other suggestions will come up. You'll never tell.

The pressure in the cooling system will always rise as the engine warms up, regardless if there's a head gasket issue or not. How do you differentiate between a normal rise and a head gasket caused rise?

The only thing the brake relay will do is turn the brake warning lamp on as part of a "lamp test". Having it unplugged will have no negative effect on anything else. I don't know anything about the alternator upgrade.

I guess I wouldn't change the title of this thread. Wayne's color diagram is for the 77, but all the 280 years are pretty similar. I'm not sure what do you mean about not being able to find files for the other years? If you're talking about color wiring diagrams, then I've seen two of them... The 77 that is the main topic of this thread, and another one for 78 that is nice, but not as complete as the one for 77. Other than 77 and 78, I've not seen anything color. For 75 and 76 I refer back to the standard version in the FSM.

Haha!! Somehow I just knew you were gonna say that!! :laugh: I didn't spend hours and hours on the ignition relay issue. It was clear that it wouldn't work right as shown, and since there was a blank terminal and another sharing two wires, it was pretty easy to figure out what happened at the drafting board. Most surprising to me is that Datsun never caught it even after four years. Also, a peeve I've got is them calling it an "Ignition Relay", when it really has nothing to do with the ignition system at all. It would be more properly called the "Ignition Switch Relay" or "Ignition Switch Position Relay", or something like that...

Thanks for the merge E. I was trying to decide if I should have started a new thread for the ignition relay issue or if I should just add on to this one, and I decided that I would start a new thread because ignition relay issue pertained to all the diagrams from 75-78, not just the color 77 version. I wasn't sure that someone looking for 75 info, for example, would pay that much attention to a thread that seems to be mostly 77-centric. It was 51-49 to me... However, I was also going to put a note in this thread as well when I got the chance, because I turned up a new issue with the color dwg. Simple oversight due to blurry dog-eared original hardcopy. There is a mis-numbering of one of the fuel injection relay connections: And some minor formatting slips as well. I love that color diagram...

Haha! So what else do you have that you're keeping all to yourself? Thanks for the info on relay options. Could come in handy in the future, but thankfully there's nothing wrong with my relay at this time. The car works fine... The diagram doesn't. I've got some projects planned for the future, but at this point it's just wishful thinking and exploration.

After much tail chasing and confusion, I turned up a mistake on the wiring diagrams for all the fuel injected cars. The problem is in the operation of what they call the "Ignition Relay". Here's the section of the diagram that shows the ignition relay, but there's a problem: You need to do this: Here's how the drawing should look: And for those of you that haven't glossed over with disinterest yet, here's what the ignition relay is supposed to do:

The CSV operates on full B+, as does the thermotime switch. (Ignoring relay and switch contact drops of course.) Neither the thermotime switch or the CSV get's any power at all unless the key is in the "START" position. The thermotime switch will open from engine heat OR it's internal heater, whichever reaches trigger temp first. (Haha. That's my zombie input. :ogre: )

Yeah I was worried about that. I guess I'm not surprised... Especially when it comes to something "safety" related. I'm sure there were changing regulations and test procedures as well as constantly advancing research, understanding, and technology.

Yup. From what little I've heard from others, that's the typical failure MO with the flat tops. They fail rich more often than failing lean. There are lots of things that can cause them to run rich, but not all of them will be addressed by rebuilding the carbs. Depends on what's wrong. If the problem is with your float levels or your power valve, then you stand a chance that it will be better when they're done. If the problem is with the needle or the nozzle, then you're scrod. You can (and should have already) checked the bowl levels yourself. I assume they're OK. My theory would be that you lodged a goober in one of your power valves when you were doing full throttle donuts. Now the goober is making it stick partially open all the time and dumping fuel into the engine. You might see if the garage would rebuild the power valves first before they took the carbs completely off the car. You can get the power valves off the sides of the carbs while the carbs are still on the manifolds. You have to get a bunch of plumbing out of the way to get access, but it's the same plumbing that would have to come off anyway if they were to pull the carbs completely. They could also use a flat plate of metal to completely eliminate the power valves if they wanted to try that. You would lose some full pedal performance, but it might narrow down the problem area. I'm sure the garage wouldn't be interested in either suggestion, but it's just a thought. :bulb: