Captain Obvious

Thanks wheee! I see they also have the 77-78 style like what my car needs. I'm just not sure I want it fifty bucks bad. I'd love to have one, but there's lots of other places my car could use fifty bucks!

That air pump I have doesn't have a hole either:

Haha! Glad to help. I'll check when I get the chance. I don't remember for positive, but I believe the pump stuff I have is from a 74 260.

I wish he did engine compartment plates for the 280. Mine was missing when I bought the car..... (wait for it!) Previous owner took the (removable) aluminum plate off to paint the car and never put it back on. Car changed ownership and I thought it looked weird to be missing that plate, so I grabbed one off a wreck and screwed it to the car. Engine compartment plate doesn't match the rest of the car and it's going to be some mystery for the next owner of my car. Just like Sweaty's.

I hate buying rebuilt parts. For all the reasons you listed above. Alternators, calipers, starters... Hate it. I've got a smog pump in a box in the shop and I'll check for the existence of that hole if I get a chance today. I could also be talked into parting with the stuff I have if you're interested. Don't know about the internal condition, but I could open it up if you're interested.

You've got a 72. As for the door jamb and engine compartment nameplates, I stand by my original theory... Someone took the (removable) aluminum plates off to paint the car and never put them back on. Car changed ownership and the new owner thought it looked weird to be missing those plates, so he grabbed a pair off a wreck and screwed them to the car. Then you bought it. The one in the engine compartment screws on and the other two (door jamb and dashboard) are held on by pop-rivets. Those three are easy to remove and reinstall.

You said the VIN stamped in the firewall is HLS30 and then just five digits? The info on the page that SteveJ posted looks like all the VIN's are supposed to be six digits. Are you sure yours is just five? And than about the mismatched numbers, seems more likely to me that someone took the (screw removable) aluminum plates off to paint the car and never put them back on. Car changed ownership and the new owner thought it looked weird to be missing those plates, so he grabbed a pair off a wreck and screwed them to the car. Then you bought it? Maybe?

Time isn't hyper critical on this one yet. I've got a couple months before this one really needs to be done. And there's no way I'm going to get into a full rebuild. I'm going to have a block worked, it's going to be in my Z, not the disposable project! I'm just looking for the sweet spot of time and cost. I'm willing to put in the effort, but don't want to waste money on a dead end.

My only input is that I can personally attest to the fact that when your previous owner puts the anti-squeal shims in backwards with the rotation arrow pointing the wrong way, the shims become squeal shims, not anti-squeal shims.

There's actually a lot to that! This project is also a learning experience for a kid. The intent is that he will be involved in the repair, whatever direction it takes, and in the end, he'll be driving this car. I think there would be more experience in fixing the broken engine than just dropping a replacement cold chunk of metal. Not to mention that I've been known to frequently throw a completely unreasonable amount of time at fixing unfixable parts...

Thanks for the input guys. So about just how hot it got? Of course, I wasn't there, but here's what I know. I was told that it was misfiring badly when they shut it off, but it runs and sounds fine now. I also know that when I went to pull the plug wires off to run the compression test, the plastic extensions that reach down between the cams to the plugs were a little melted onto the spark plugs and the plastic extensions snapped off leaving some melty portions stuck to the plugs. I don't know what kind of plastic they used for the wire extensions to reach the plugs, but whatever it is, the engine had exceeded the melting temp for that plastic. Runs fine now. Plug wire extensions had melted, and in general smells a little burney plastic when you open the hood. That's about all I know at this time. One of my pushbacks on a replacement engine is the ability to do a compression test on a replacement engine that has already been pulled out of the donor vehicle? Sitting on the floor in the corner of the shop? If I bring a starter along, I might be able to bolt it directly to the block even if there isn't a transaxle attached? Anyone got any bright ideas? If I'm going to drop one in, I certainly want it to be proven to me that it's better than what I've currently got. I guess I was thinking of pulling the head first anyway and having a look at the bores. I've been into other import motors with twice that mileage and I could still see the remnants of the original hone crosshatch. So I guess my path forward is, pull the head, look at and measure the bores, and if they look and measure good, I may cheap out and just throw a set of rings in it and see what happens. But if the bores measure worn or if there's any scoring, metal transfer, or discoloration, I'm going to bail on the job and look for a replacement drop-in instead.

Off topic alert. I'm asking here because the level of experience is much higher here than where I should be asking. I just bought a cheap disposable Hyundai. It was overheated significantly by the previous owner and because of that, it needs engine work. No surprises here. I knew about all that before buying it and I got it cheap enough that even if I have to replace the engine completely, I think I did pretty well. Here's where I am... I know the head gasket has been compromised and I'm assuming that the head has warped as a result of the heat and will need to be planed flat. But before I pull it apart, I'm trying to figure out what else is wrong. I don't want to dump a bunch of money into the head only to find that the engine should just be completely yanked instead. The engine has 120K miles and the compression test numbers don't look too good. Wet looks great, but dry is below the service limit. So it sounds like rings or worn cylinders, but at 120K miles, I would be disappointed if it was just normal wear. So here's the question... Just how hot do you have to get an engine before rings lose their temper? Is it conceivable that the engine overheating episodes ruined the rings? is it conceivable that the pistons and bores are OK, and I could get out of this with just tossing new rings on the pistons?

Yes, if you've got the diode on the green, then it should protect against a grounding path. That's not what it's for, but it will do that as well. Actually the best thing would be to have diodes on both wires feeding that relay. Diode OR them together such that either of them could feed the relay without affecting the other.

And yes, it's completely conceivable that whatever shorted was far from the fuse block. For brief periods of time, copper wires can carry an enormous amount of current. Even the smaller ones.

Regarding the override wire shorting to ground in the engine bay, I don't think that would cause the issue you had, but it could be a problem. If you've got it wired as shown in the instruction sheet and the ignition switch is on, when the temp switch closes, you've got +12 on the yellow wire. And since the yellow and greens are tied together at the module, you've got +12 on the green. Shorting the green to ground would be a connection to ground through the ignition and temp switches. Also, a little unrelated, but just noticed that they have a diode on the override wire. I'd put it on the one coming from the ignition switch instead. The way they have it, you can't back power the override source from the ignition, but I think it would be more important to make sure that you can't back power the ignition from the override source. Especially if the override source is hot at all times. Did I say that right? Does that make sense?

Stumps me. I looked through the literature I've got and there's nothing even close. That's why I hadn't responded to date.

Replica Cobra. Nobody is going to take a proper one out without a surrounding of bodyguards.

Wow. Those are some nice looking front end parts! I got two other comments: First, there have been reports of snapping T/C rods when using poly bushings on both sides. Now I don't know if your aftermarket rods are stronger than the stock rods (probably are), but you might want to look into that before using poly on both sides. Second, You used a force gauge to check the preload on the steering rack? Seriously?

Well the biggest bummer right now is that if the problem spontaneously went away, you can be sure that it will spontaneously come back again. Are you double dog sure it doesn't have anything to do with the electrical work you just did? You were messing around up front near the parking lights with the fan install. I know it's unlikely, but just seems too coincidental.

Well duh. Who doesn't!!?

Well that's a bummer. So looking at that fuse and the cover, here's my forensic analysis of the whole situation... (Warning... Heresay and theory alert) You have (or had) a dead short somewhere in your parking light system. That dead short occurred spontaneously as you were driving. Hit a bump? Something maybe that had been very close to shorting for some time finally picked last night to be the time when it went the rest of the way? Or maybe it's related to the electrical work that you have been doing recently? That spontaneous dead short blew the fuse so violently that you ended up with arcing sparking inside the glass tube along with ionized air and metal mist from the vaporized fuse material. That ionized air and metal mist allowed an arc to form (just like welding) and that arc not only allows current to continue to flow, but it also produces mucho heat. Certainly enough heat to crack the glass and melt the fuse block plastic. So, you've got this dead short in your parking light system and a fuse that is still passing huge current even though the metal strip is long gone. You're pulling many amps through the dead short, and because of that, your headlights go dim (which looks to you from the driver's seat like they went out completely). Then after some period of time, the arc finally stopped. Maybe the fuse metal burned back so far that the arc could no longer be sustained. Maybe when you flipped the headlight switch back and forth a couple times, you were able to break the arc? Maybe whatever shorted in the first place became spontaneously unshorted? Maybe the high current melted and opened a wire somewhere? In any event, the high current draw stopped, your headlights were able to come back to better brightness, and everything else, other than the parking lights, went back to normal. And for those of you who are wondering "OK, so if this is all true, then why didn't a fusible link blow?" Well here's why... For whatever reason, in Datsun's infinite wisdom, there are a bunch of circuits that hang directly off the alternator with no fusible links between the alternator and said circuits. They are a direct connect to the alternator, and in the case of a hard fault, are happy to suck down as much current as the alternator is willing to produce. I don't know if this is a design oversight, or on purpose for some reason, but that's the case, and yes... The parking light system is one of these "non-link protected" circuits. So, my first question is... Is the short still present, or did it fix itself as mysteriously as it occurred? You can't simply check with an Ohmmeter because all the bulb filiments will make it look like a short to ground (even though it might not be). I would put a new fuse in that spot (like a 5A fuse?) and turn the parking lights on while you watch that fuse at the same time. if the parking lights come on like normal, then you've unfortunately got a continued mystery. If that fuse goes up like a flash bulb, then you need to start disconnecting things until you find out why.

The 78 fusible link for the headlights does headlights only. Nothing else is on that circuit. What's the state of the issues now? Is everything back to normal, or are there still lights that aren't working?

Dennis, That would be such a fine site to see. Thanks for the tip. I'll be sure to do that if I ever make that journey!

So do either of the two restored service stations pump gas or work on cars, or are they both just tourist stops now?

Ignore the dents in the dash and focus on the rest of the car. Pretend the previous owner did it.