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3D printing gets a bad rap sometimes because the designer had no idea how to design the part to be 3D printed. Done correctly it is an amazing tool that is capable of making many intricate parts that can't be made conventionally. We use it a lot for aerospace and automotive components, material choice is critical and also print orientation to ensure the correct load profiles. We use FEA analysis and optimization software to get the strongest parts possible.

Inspired by a couple of recent posts on the Bring-A-Trailer thread, here's a thread to show some of the 'It wasn't me' type beastliness inflicted on cars by previous owners or their paid minions. I think we've all seen them. To get the ball rolling, I present to the jury this absolutely arcane replacement fuel filler arrangement on a 1970 car. I had been asked to perform an inspection and appraisal of the car for its new (and somewhat green) owner before he commissioned a restoration by a specialist here in the UK. Being an early Japanese market variant with a low production volume, a second opinion was being sought and I was happy to oblige. Lots (lots!) wrong with the car, and this particular example was not even the worst of it. A used rear quarter (in fact, totally the wrong type for the production year of the car...) had been attached but it must have somehow been supplied without its original fuel filler 'box', prompting the attachment of something from an entirely different vehicle (answers on a postcard please) and some mind-bendingly arcane domino-effect er, 'fabrication'..... I'll let the photos speak for themselves, but just add that the latching mechanism (look closely) was verging on 'field repair' genius...

First, a little history about me and why I love Z cars: Ever since I was a little kid, I have always loved the Datsun Z car. My uncle had a 1970 Datsun 240Z that provided many fond memories. I always told him, “If you ever sell this, call me, I will buy it from you.” Unfortunately, that day never came because it caught fire while parked in the driveway after a Sunday drive many years ago. The fire mechanically totaled it. I was so upset and angry, but I am sure that my grief was nothing compared to my uncle’s emotions. Fast forward to the present (or at least a few years ago). My son (much like his father) develops an interest in cars. I decided that I was serious about getting a collector car and something that I could wrench on and keep my mechanical engineering brain active (I have ascended to a management level professionally and I think my technical skill cells are in danger of being overwhelmed by management and bureaucracy!). Anyway, the first cars I was serious about buying I was a little late to the ball. There was a 280Z that someone had restored online for his son in the Midwest and was selling for ~$7500 if I recall correctly. I missed out on a bid on Bring A Trailer on a nice 260Z a few years ago because the kids were going crazy in the background when the bid ended. I saw a few Z’s locally here in Maryland, but those ended up being too rusted out or basket cases that were beyond my abilities to restore. So I widened my search to all cars I was interested in. I went and looked at a 2000 Corvette C5, but that was a case of never meet your heroes – as I was very bothered by the perceived cheapness and lack of durability of the interior and quality issues that seemed to be present with that car. I missed the ball on a ST-185 Celica Alltrac (always will love those), and got ghosted by another seller when I asked to see it and set up a Pre-Purchase Inspection. Then I came across my Z, which was somewhat local (within 100 miles) and I thought was worth a look. It passed all the tests and a mechanical inspection, and I couldn’t argue with the price, so I walked away the proud new owner of a 1976 Datsun 280Z. I name all of my cars after videogame characters, so I thought with the color and vintage, naming my Z after the main character of the classic video game Metroid, Samus Aran, was quite fitting: I think I am the 4th owner. As far as I can tell, I think she was very well loved by the previous owners, as the car came with a lot of records, a service manual, the original owners and maintenance documents, as well as even the original window sticker!

I don't want to jinx myself, but I think I fixed it! I was determined to do this myself and what really held me back was not having the right tool so I upgraded my wrenches and tried one more time. Got it lifted grabbed a few open wrenches and attempted to tighten the existing compression fitting. It was a bit easier this time and so far about 5 hrs ago not a drip. Now it is 105 in Sacramento so maybe a pinhole still exists and it's immediately evaporating but the finger test so far is holding true. I will check again over the next few days. I have a new compression fitting if I feel it needs replacement but so far so good. Again want to thank everyone. For someone like me still learning and trying to do this all myself I feel real good about what I've accomplished so far. 🙂

Not sure about this fellow but I bought a 3D printed inspection lamp lense at a reasonable price off eBay and found it to have the 3D printing grain so rough that I had to send it back for a refund. Beware of the finish quality / resolution on some of these items. And have to say, I shudder when people print intake manifolds (a racer TVR buddy of mine recently did this) - I’ve not found the integrity of 3D printed materials to be as good as cast or injection moulding! One of my cycling buddies bought an expensive 3D printed bracket to fit his saddle for his rear camera / light / radar gizmo and had it snap as we were riding just 500 miles later - yet my cheapo Amazon Chinese aluminium one hasn’t failed in 4 years! Now imagine an intake manifold coming apart mid WOT action at 6k rpm!! :o

Hello all, I would like to do a little advertising for this channel here. One of my Z friends is restoring a 240Z and has a very special way of documenting it. I think you will all be very interested and it is super relaxing to watch. In general, this is a very exciting channel!

🤣 That's the main reason I got the Z. Imparting my knowledge to my son should also help keep me on my toes, he asks questions non-stop and has a neverending curiosity of figuring out how things work. He's become quite the mechanic's assistant. The Z needed a few things, as no 47 year old car is going to be perfect. Speaking of which, thus far it has needed a new fuel sending unit, speedometer cable, a new wheel stud and lugs (one on each wheel), battery, and fender resecuring, all of which were performed by the mechanic that performed the inspection. My son and I found that the car didn't have a windshield washer fluid tank, and it needed an oil and filter change, as well as a new fuel filter, so we have done that. It has developed a recent more pressing issue with fuel delivery. The Z runs fine when started cold and warmed up, at least until a significant load is applied and then it begins to drive really rough, eventually stalls, and needs to sit for a long length of time before restarting and is ok to drive again. I will likely ask for help in the technical threads, as I have tried to troubleshoot but it has been driving me insane. As far as long-term plans, I may get it painted (it was once already in the 1990's, but it is showing its age and wasn't the best quality). When I do that I will likely need to get two new front fenders, as these have some rust and Bondo. I'm also not in love with the likely period correct 280Z decals and pinstriping on the lower sides. I think it's also going to need rear shocks. The P.O. also planned on replacing the rear drums with discs, and included the discs in the sale - this and the shocks may be my winter projects. Some Panasport rims and new tires would also be nice. The current 8-track stereo is non-functional, which I may just remove and install a blank panel. With the stock speaker locations and the loudness of the current exhaust (may also be a future change, my mechanic referred to it as a "cheap muffler" and the pipe is noticeably the lowest thing on the car), I think I would be better off using my phone and a nice bluetooth speaker for music. Once upon a time I was into installing stereos, amps, subs, tweeters, mids, etc., but I think there are now far better things I can do with my money. Paul

OK, hopefully this does it even if it's temporary. I was able to get the old fitting off and maybe understand what had happened. It was the type of fitting that required a flange not the traditional compression with sleeves. PO made some nice flanges, seemed clean without burs but i noticed on the tank side the tube at the flange was just starting to make a turn ever so slightly. You'd never really notice unless it was cutoff to inspect up close. So i think the flange wasn't sitting perfectly flat inside the fitting. Got myself a micro sized pipe cutter and with enough wrangling was able to cut it out. Removing the mounting screws all the way to the filter and a few in the tunnel got me enough play to get it done. Thanks for that tip. For some reason I look at these hard lines and am always so worried they're going to be stressed to the point I make it worse. Lessen learned. Ok now to the fix. Cutting the section out resulted in a gap too wide to bridge with another sleeve compression fitting no matter what i did. I had to resort to hose and clamps but since I couldn't get the bump ring on the end of the pipe i used 7mm instead of 8mm hose to make it more snug. At some point I think i can get a new section of line and make the bends to get a true compression on there (unless I just ignore this until i get a real opportunity to replace it all). I will leave it overnight again as it's too hot in the garage to know if its evaporating like yesterday. It started and ran excellent so that's a positive. If it does work, here's my trophy and I'm hanging on to this one! Thanks all!

Just say no. Get an old carburetor. Doesn't matter what kind, or even if it still is functional. Every weekend go out to your workshop, take it apart, and then put it back together. Repeat every weekend.

Regarding the oil level on the dipstick, I believe the sump capacity is 5 quarts. After changing oil and refilling, run the engine (so the filter is filled) and shut the engine off. After about 10 minutes check the level. That should give an accurate reading, and if it doesn’t match the dipstick, then make a note of where the level is in relation to the original marks. Now on to the oil pressure. The rule of thumb, for any engine, is 10 psi for every 1,000 rpm of engine speed. So at 5,000 rpm, it should have 50 psi. The stock gauge is not an accurate gauge. You can use a good quality mechanical gauge, for peace of mind, to compare to the stock gauge. Also note that cold the pressures will be different than when the engine is at operating temperature, and will fall off some. Nothing to be concerned about, provided the 10 psi/1,000 rpm rule is met. Being in California, you might also find that 20-50wt will give better oil pressure in the summer.

Maybe just spanning the gap between the old crusty hoses ends. Looks like a new FPR though. Strange. @zspert, that old braided fuel hose could blow, or just slow leak from longitudinal cracks, at any time. It's on the high pressure side. I remember that soon after I bought my car, after I had installed a new pump and got the car driving well, I was pulling out of my neighborhood and a UPS truck driver pulled up beside me to tell me that fuel was pouring out from under my car. A PO had used low pressure fuel line and it had split. Luckily everything was cold and I was within walking (running) distance to my house where I had some spare hose. I was able to squeeze under the car which I had parked next to the curb behind a strip mall to replace the hose and get it back to the house. I felt bad about the big gas stain on the pavement but at least there wasn't a pile of melted plastic and tire rubber.

Many people don't really understand what the sealing surfaces are in a compression fitting. It's important the surfaces are clean and that the tube is round, not distorted. It could be also that the Nissan 8 mm nominal tubing dimension is just not right for the typical US domestic automotive repair kit. Things to think about. Good luck.

High dollar lawn mower? Harbor Freight wind tunnel?

Yes, that it. It's the later 1978 onwards fuel pressure regulator. It serves no purpose on the pump. Without vacuum it will provide 2,5barg and you will still need exactly the same thing after the injectors to reduce the pressure to compensate for the vacuum in the manifold. Someone probably thought the pulsation damper looked like a regulator and replaced it with one. Could have just left it out all toegether. According to the bosch FI manual, the dampers main purpose was noise reduction more than anything else and this system is basically a bosch system.

Those look like painful hemorrhoids.

Late to the party but Z Store does sell a single bulb type outer hatch seal i just installed on my 71 if you're still needing it. Came outr great with just the 3m adhesive. https://www.thezstore.com/product/5487/rear-deck-outer-weatherstrip-one-piece-top-sides-70-78-240z-260z-280z-coupe

I'm always shocked when I see a seemingly nice Z with lights installed backwards. It tells me that the owner/restoration shop doesn't know Z cars very well. What else did they do half-arse?

To change the subject a bit - Had a 280 recently sold on BAT towed to my shop for a once over for the new owner. The car has very low mileage. It almost goes without saying that the rear brakes were frozen. Got the right rear wheel off and discovered this "modification" had been done to the fuel pump. As these cars age I see more and more generations of butchers plying their trade but this is a new one on me!. Now, what was he trying to address with this trick? Cheers

Well your first issue in my mind is you need to stick with stock efi. That rules out most mods. You can probably tinker with the setup but the problem comes in when you cant tune the system for a deviation. Also you would be searching for dished not domed pistons. To really determine the bore condition you would need a way to measure bore ID. 3 places down the bore. Side to side and front to back. If there's no lip at the top of the bore you might could just hone if your measurements are good. But you might hone and then have to bore and re-hone. It sounds like these shops are approaching this from past experience and the highest percentage of success. As for the crank, if it mic's out, is round and looks good, a light polish would be better than grinding. It's easier (maybe lazy) of the shop to bore and grind. The upside for them is they know for certain the crank is true and round. They also know the bores are all true, cylindrical, straight, consistent and without taper. All good things. It also takes some time to do all the checking versus just chucking it uo and punching it out. These old Nissan blocks were made out of really good metal and these shops may not have a lot of experience with how well they hold up

I'm guessing it was for ground effects and not getting rid of exhaust in the cabin. I wonder if it worked for either one?

I posted several pictures on Hybridz back in 2020 (Polyvance dash repair - Interior - HybridZ) Also, check out the Polyvance web site - they have a video of a 280Z dash repair. This was the outcome:

The switch is but a commonly available SPST toggle switch, easily replaceable unless you want to match the Nissan white plastic switch throw lever. This one is available form Amazon : about $4 Any autoparts store should have one.

Check out this ugly one that is currently up for auction on eBay: