Zed Head

The ad says the brand is "Martin" and the eBay store is Martin's auto parts. Looks like he's selling cheap Asia knockoffs. $30 + $65 = what I paid back in 2009 for an Airtex. My Airtex pump has lasted probably 40,000 miles or more, still works great. So $65 for a known quantity (IF the zcardepot pump is an Airtex) or $30 for a mystery pump.

Eurodat and Dave WM have both been deep in to the 5 speeds. Seems to me that most of the parts are available so as long as the adapter plate bearings haven't blown up, which they do sometimes, and the gear cones, for the brass synchro to ride on, aren't rusted or worn out, it should be rebuildable. Another common wear area is the nose of the input shaft, if somebody let the pilot bushing go bad. The tail shaft housings tend to get chipped from dropping also. The "snout" of the front cover, that the throwout bearing rides on, can get pretty worn. They've been known to break off if very worn. The output shaft bushing, in the back case, can get very worn also. Some of the guys have found a fix for that problem. I bought a mystery 5 speed that turned out to be destroyed inside. It went in to each gear when I was looking at it but once it got spinning on the end of a motor it started crunching. I thought it might have problems though so I tested it in the garage. I only paid $50 for it and used the front case for a 71C swap. That story probably doesn't make you more confident. The drain plug magnet will tell a story. If it's been freshly cleaned, that's a concern. @EuroDat @Dave WM

Any chance your bulbs are just burned out? It seems like you've tested the circuit from end to end. One thing that can happen when testing using a meter is that the meter will measure proper voltage or continuity through an iffy connection (loose or dirty), then when current flows through the circuit the iffy connection gets hot and opens up. Pretty common for starter problems, because they draw a lot of current. In your case, since you have high beams, it might be a bad connection at one of the connectors on the way back to the dimmer switch. It looks like C-2 is on the low beam circuit, it doesn't branch off to the high beam indicator. Red with black stripe by the color diagram. Good luck. It's a tough one. High and low share the same power source so it has to be on the ground circuit if the high beams work.

So you're making progress. Not clear what "proper wires switched on" means. Sorry. Just don't know. Based on the diagram you should be able to take the pug that connects to the combo switch and jump the wires to see if it's the lights or the switch. Be the switch. Make sure you pick the right pins, and use a test light as the jumper if you want to be safe. The test light will stop you from creating a dead short.

Bad gas is hard to diagnose. It just doesn't light up like good gas. You could drain your float bowls and refill them with known fresh gas as a test. Did you check that when you pull the choke knob/lever that it's actually moving at the carburetor? You might be pulling the knob but nothing really happens. I'm just throwing out guesses that I might try if I had the car and the problem.

Pumps are actually getting cheaper. The zcardepot pump picture looks like an Airtex. They used to cost ~$99. You should post the actual links. The pictures aren't worth too much for figuring out value. https://www.rockauto.com/en/catalog/nissan,1977,280z,2.8l+l6,1209248,fuel+&+air,fuel+pump,6256

That's a good clue then. Here's another clarifier - were you driving it when it "stopped working" or do you mean it just wouldn't start one day? Any chance you got some bad gas? Did you follow the proper starting procedure? Maybe your choke cable came disconnected and you've lost choke. Only posting to get some carb time. Don't really know much.

Try starting fluid through the carbs before getting too crazy. Confirm that it is actually a fuel problem. I've had weak spark that wouldn't start on gasoline but would on starting fluid.

It might, but there's not a lot of range there if I remember right. The slot is small. There is also some adjustment possible on the pickup coil, maybe. There is on the two pickup distributors, for phase adjustment between the two. Do you still have the old one? You might examine it and see if it has been adjusted. Might b that the PO was one tooth off and made his own fixes.

Here's the back of a Remy 1982 280Zx internally regulated alternator, for comparison. If you just bought the car it might already be wired for an internal alt. You didn't really say why you changed the alternator so your original problem might still be there after you get the right parts back in to it. Welcome to the club!

I think that you might have an internally regulated alternator with an external regulator. The "P" is only found on the internal reg alts, I believe. It's some sort of tachometer for more advanced charge control systems, I think. Change alternators of wire it up for an external regulator. No real advantage, one over the other, for a 77. They're both 60 amps.

If it runs, a drive around the block with some brake stomps would probably tell a lot about any sub frame bending.

Does it spark once while the engine is turning over but then not again, even while the engine is still turning? Or does it spark once when you turn the key on and off? The ZX distributors are known for breaking the magnet under the stator ring, and for bad bushings that allow too much play in the shaft.

Check for security or traffic cameras. They're everywhere these days. Maybe even post an ad somewhere asking if anybody saw it. They'd probably remember seeing a nice looking Z spin out on the Ballard bridge. You never know. If the door gaps aren't squeezed tighter and they still open and close correctly, the front of the car can probably be fixed. Door gaps are my accident "tell".

That's a bummer. Now you can get another and start over. Those HEIC files must be for phones. They don't come through on a computer. Edit - my Windows 7 computer anyway.

It was fuzzy. I'm just glad there were no Newton-meter/seconds, or watts.

I think it depends on how fast the broken piece stopped spinning and how extended the open valves are. Inspection will tell. The back cam tower could be removed and the broken half lifted out, I think. That might be fun.

Here is the source of the color wiring diagram - https://www.classiczcars.com/files/category/1-wiring-diagrams/ And the FSM has the schematic of the combination switch. B is the key. It's a pain tracing out all of the wires. I'd draw a diagram of the socket and label each one. Then take your meter and make sure that you have continuity through the switch when you should. Also check your grounds to be sure that they actually ground. The lights are all about the ground circuit.

That does suck then. The quick and dirty fix, if no valves are bent, might be a cam shaft swap. I think. Slide the old parts out and the new parts in. Might as well loosen or remove the towers then use the tap, rotate, and tighten method to be sure it spins free. If you brought the rocker arms over with the camshaft, it might not even know it's in a different engine. I've looked at a bunch of cam specs and they're all about the same. I think the ZX's were probably changed for better emissions, nothing dramatic. After the mid-70's, most changes were about emissions. It would be an interesting challenge, to see if you could make the swap without destroying another camshaft. The key to finishing it is to avoid the while-I'm-heres.

The dyno stuff starts at about 10 minutes. 175 MPH!

They came through well. Looks like an R180. Pretty crusty but it's a dry crust. I don't know how solid the FSM data is. An R180 from an 810 would swap over though, from Terrapin's chart. Regardless, if you're sure it's 3.7, it probably is.

Nissan implies that it is. Are you planning to pull the head or just go ahead and swap engines? Did you look for stuck valves? Seems like if the shaft broke in the wrong spot a valve would have got bumped. Don't forget, we love destruction, even though it means more work for you, so take more pictures. Weren't you getting bored anyway...?

Seems like your contradicting yourself in your description. You said your low beams don't work, then said that they do work. Sounds like the dimmer switch has a dirty connection. The headlights work by grounding the power. Then you said that the stalk has no power, but you measured 12 volts. The turn signals work by sending power out to the lights, where they are grounded. So if you have power to the correct place it should get through and out to the lights. If the lights aren't grounded though, they won't light up. If you have the combination switch off you can test both of those by measuring continuity at the plug. You just have to identify the correct pins. Don't forget that the Hazard switch is part of the signal light circuit. It has to be working right also.

That's an odd number for a 73 240Z. Is it still the R180? It's still a good ratio for any of the 5 speeds. The 71C front case swap is a nice option if you get a later model 240SX transmission. Synchros in reverse and some have double synchros on second gear. Plus wider gears, physically, than the early 5 speeds.

The $1200 -1600 must be for a completely rebuilt transmission using Nissan parts, at a spendy shop. That is a very very high price. The other comments are on though. I put a 5 speed in my 76 and after I got the engine running right, smoothly, I often found that I was still in 4th on the freeway. The other end is 1st gear. Taking off from a stop. If you live in the hills, a 13:1 overall ratio in first might be appropriate. 3.9 X 3.321 (Z or KA/71C), for example. If you're on the flat lands, maybe a 3.54 and a 3.062 (1980+ ZX), 10.8.