jonathanrussell

When I rebuilt mine, I took some photos after disassembly and made sure I kept things in order so I think this should help you. My photo isn't the best but ...the order starting from the outside hex bolt/plug goes.... 1) Hex plug. 2) Seal with flat side out and U cupped shape in. 3) smaller washer. 4) snap ring. 5) larger washer. 6) spring. 7) shaft (see photo for orientation). 8 ) Seal with flat side in and U cup shape pointing toward the hex plug/out. Essentially the U / cupped shape of the seals both point toward the center. I used a 5/16 socket to push the assembly down and cause the snap ring to re-seat when I reassembled. I used the MSA seal kit but really I think the original seals were just fine. Mostly what I accomplished was cleaning out 45 years of gunk.

Sounds like you really know your way around these cars so I am guessing you have the carbs tuned well. But, I have found that these cars like to idle a bit rich. If you try to set the mixture too lean, you get (I get) terrible idle performance and backfiring through the carbs. If you apply a bit of choke while idling does it straighten out?

https://www.ebay.com/itm/1974-Datsun-Z-Series/113690222495?hash=item1a78771f9f:g:1jUAAOSwGN9cjw8K

https://tampa.craigslist.org/hil/cto/d/fort-lauderdale-1974-datsun-260z-trade/6845092595.html

Take a look at the EuroDat's photo in his post #6 at this link.

I am pretty sure @EuroDat has a photo that shows the seals / o-rings with part numbers so he may be more helpful too.

My recollection is that it looks like most any other seal...inner dimension, width, outer dimension. I have a spare or two but am traveling for a bit so can't photo / measure.

I bought them from Courtesy Nissan. But, it was a couple of years ago when I bought so I don't know. If I were looking to buy today and they were unavailable I am pretty sure I could find the same sizes from other generic sources.

My concern about trying to seal your leak from the outside is that the shift mechanism rotates left and right all the time when making shifts. I think that whatever you do from the outside will fail to seal, get lodged, etc. I replaced the seals in my shift mechanism last summer and if I recall, in addition to the O ring, there was also a little seal. The hardest part of the job (for me) was removing the fork from the shift rod. There is a wedge bolt and nut. The wedge bolt is kind of like the wedge bolt that keeps the rear suspension spindle pin from rotating. It was really hard to get enough leverage to push out the wedge bolt, simultaneously being careful to not bend / break anything. Heat was the key and @EuroDat was a huge help giving me some advice. After that, it was an easy job and now I have no leaks. I was also getting gear oil filling up the cavity where the gear shift lever attaches to the trans. I also took this opportunity to check the bearings and replace all other seals and gaskets.

I have three zcars. With each, my dad and I took a flight to the car and drove back to Atlanta. My dad and I had a great time along the way each time. Two of the three had mechanical issues that we had to deal with along the way though. Still...I would do all three again. First car was in Portland. Second car was in Phoenix. Third car was in Hershey PA. Each time we packed a suitcase of tools and a few spare parts. There was a long arse night in a pretty bad hotel in Midland Texas though. Car was running terrible. Fortunately a spare AFM for a 280 came in handy the next morning. I would say though...I would not attempt if the car didn't start, drive, stop, etc well enough when I tested it out in person. Because of the questions I had asked prior to the sale though, I felt good about being able to fly out and drive home with parts and tools. If the car didn't check out in person I would have made arrangements for transport...uhaul and rental, or transport company and fly home.

Maybe a way to come up with a price is to first figure out what Eiji at Datsun Spirit or Dave Rebello would charge for a similar engine with similar hp numbers. Once you know that, I would think you also have to realistically know that the likelihood that you can charge the same as a proven engine builder is pretty slim....regardless of how nicely done your engine is. After that maybe you figure out what the discount is from a proven builder's price. In the end the market will determine what someone is willing to pay.

Hi and welcome. Sorry you are having problems with your new 280. Keep this in mind though. it ran well recently so chances are you will get this sorted out and it will run well again. It worries me a bit that the prior mechanic wrote that they leaned the mixture. There really isn't a way to do that without screwing with the AFM which causes all sorts of other problems. Hopefully he did nothing. FYI, I watched your video. It sounds a lot like my 75 did at one point. I like your list of things to check this weekend. I would also remove the AFM boot(s) and check the inside of the AFM to see whether the Flap is stuck open. It should close when car is off and move freely up and down. I have seen an intake (not exhaust) backfire in a 280 cause the AFM flap to bend slightly. When this happens it can get stuck open. If it gets stuck open the car meters all the time like you are at WOT. My 75 had this problem and ran very much like yours in the video. Best of luck. Don't get discouraged. You are going to really enjoy the car once you get it sorted.

I rebuilt my rear hubs this past summer. I did all of the work myself and was very careful about keeping the components exactly in order. My bearings were original and the grease was consistent with original grease. That combined with what I know about the car history makes me pretty sure the hubs had never been rebuilt prior (can never be positive though). My hubs have the copper phosphorous spacer. Here is the order of parts that I found starting on the inner hub...diff side. Crush / lock nut. zinc plated steel washer. companion flange oil seal copper phosphorus spacer (sandwiched between inner bearing and companion flange outer surface) inner bearing bearing spacer outer bearing axle / outer hub. To me, if your hub and spacer are matched with the same letter, I don't see how you could add a spacer between the bearing and the bearing spacer and have everything work right. Maybe they were mismatched and the spacers were used to solve the mismatch? If you decide to not use the copper spacers, take a look at the technical bulletin mentioned above. There is a different torque spec with vs without spacer.

The master vac numbers seem more like a punch to me. I have the harbor freight number / letter punch sets in 1/4 and 1/8. Have never looked to see how closely the font matches though. https://www.harborfreight.com/36-piece-18-in-steel-letternumber-stamping-set-63676.html

MSA sells a seal kit I have used successfully to refresh my valve. https://www.thezstore.com/page/TZS/PROD/24-5556

MSA sells a seal kit I have used successfully to refresh my valve. https://www.thezstore.com/page/TZS/PROD/24-5556

MSA sells a seal kit I have used successfully to refresh my valve. https://www.thezstore.com/page/TZS/PROD/24-5556 Apologies for the multiple posts. When I hit save, didn't work as I usually see. Sorry.

Have you checked the direction of the booster check valve as suggested above? I am scratching my head as to how the problem could be anything other than the booster or vacuum feeding the booster. In my experience, pretty much every other negative situation in the brakes leads to a soft, spongy, whatever, pedal. I suppose if a wheel cylinder were frozen solid the result would be a harder pedal but... If you block the booster vacuum entirely, does anything symptomatically change in the way the pedal feels? Definitely check the direction of the check valve. If it is backwards, it will feel like no booster...thus hard pedal. Even though the pedal is hard, does the car stop as it should...assuming you give enough leg effort?

Seems like we are missing some information from the OP. What do you mean by the word "cheap"? Please give us a dollar amount that you want to buy the car for. Is this going to be your sole daily driver or is this a project / fun car, in addition to your daily driver? If this is a project, how much of a project do you want? Do you want it to be a totally functioning and safe car from day 1 that isn't a rust bucket, starts, drives as it should, stops straight, etc, but can be improved over time with multiple projects? Or are you looking for something that may not even run that you will need to solve multiple significant issues before being able to drive and enjoy? My general thoughts and opinions .... If this is going to be your daily driver, a cheap zcar isn't going to be your friend. Instead, if you want a modern car that has a similar DNA, consider a NA Miata. As far as price goes, what you are reading above is that the market for the S30 cars, and in particular the 240z models, has skyrocketed. What you really need is a time machine. Let me know if you find one. The problem with "cheap" zcars is that the initial purchase price typically tricks the inexperienced into thinking they are getting a bargain. To me, the sweet spot for someone wanting a relatively rust free car that starts, drives as it should (though not perfectly), is safe, stops straight, has complete interior that needs some attention but isn't a rats nest, is a 280z that will cost between 8k and 12k. Unless you have a friend of a friend who just gives you a great deal, I don't think you can find a 240z that has these qualities for this price range in the open market.

@motorman7 used Sav-On plating. See post 135 on page 6 of his bringin' back the flat tops thread.

I would go for the P79 NA engine you show above. Looks clean and complete. The one cam lobe you show looks good. Pull plugs, make sure it turns. Might pull the valve cover and give a good look at cam.

@KONI Lee....Also...one question from me regarding the new Koni / MSA Yellow offering. Some of us have noticed that when installing gas charged strut inserts on our cars, compared to non-gas charged like the Koni Classic, the ride height rises an inch or so. Do you think this will be the case with the Koni Yellows? Specifically if you compare Koni reds with the new Koni yellows on the same car with the same springs, would the yellows cause a higher ride height? Thank you.

@KONI Lee ..... thank you for engaging in some Q&A. If you don't mind, and since we are on the topic, can you comment on the red Koni Classic strut inserts produced during the past 4-5 years for the 240z? Were they the same as or an improvement on or totally different from the 80s era 1811 and 1812 strut inserts? I have them on one car and like them very much. They adjust just like the 70s and 80s strut inserts.

@James@TheZStore ..... ZH makes a great point. Koni makes great soft bump stops and it would be fantastic if you guys would sell the model or models that have an inner diameter that fits the shaft best.

Based on the photos so far, you stole the car. Congrats and welcome.