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About Johnny280

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  1. Update: I removed the carbs and had a good look at the linkages. There were multiple things wrong: 1. the choke cable was indeed too tight and was preventing the spring to get rid of the play and keeping the nozzle completely up. 2. a wrong bend in connecting bar A resulted in the sticky nozzle situation. After some time I was able to bend it in a fashion that a) the nozzle stays up b) the nozzle is not sticky c) both nozzles move the same amount 3. had a look at the connection rod to the butterfly and bend it to match the specs in the service manual (between 0.59-0.69mm butterfly opening on max choke) Next step is to refit the carbs and get the choke cables on a little bit more loose then the last time. The original plan was to just swap the SM needles to SB needles to see if i can lean out the idle (had some filthy rich idle hot @10.5 while cruising @16+) a little bit while keeping a richer mixture at full throttle and cruise - lets see if that works out. Thanks again for the input and the reassurance that there was nothing wrong with the linkage.
  2. Thanks a lot for everyones input so far. A lot of stuff I have to think about. I will try to analyze the clamping situation first and fiddle around with all your different methods, then probably get the carbs out to check the linkage for canting. @siteunseen: The carbs are suppose to be ZTherapy rebuild ones and the rubber hose seems to be of the right type - flexible silicone ones. Regarding the Choke attachment. Yes, i replicated that one after wasting half a day building my own idea (wasn't aware that the internet had a pretty good solution). Mine was working but too bulky to fit under the console. One day I will place an order with ZTherapy and on top get one of those famed DVDs. @Captain Obvious: The flooding was pretty close to us but luckily we dodged that bullet. It was more to the south but a lot of the water was flowing down via the rhine which is only 300 meters away from our place. Waterlevels were not critical but unusually high for summer. Fortunately yesterday was only constant heavy rain (real German summer). I read somewhere that original SUs are first opening the butterfly and then enriching the mixture. Are our Hitachis the same in that regard?
  3. Hi, good to hear that sloppy is normal. First I will check the choke cables. Last time I worked in that area I was adding a floor mount for the choke lever and swapped the old cables with new piano wire (very smooth action now). I know that i brought the 'clamp lever' up to the point that i could feel the spring resistance starting to have immediate action when moving the choke lever. Should I leave some margin there? If that doesn't solve the problem I assume that the up and down play in Connecting plate A to the 'unknown plate' needs to be adjusted by bending Connection plate A in such a fashion that 1. the nozzle is not canted, to prevent any binding (current situation) and 2. in case of choke off keeping the nozzle completely up (in that position no up-and-down play should happen). Currently i would need to swim to the car. I will try to get fresh pictures of the return spring assemly as soon as possible.
  4. Hello, I was chasing down (again) a problem with a stuck open nozzle when easing out the choke on my SU carbs when I noticed some weird play between the Connecting plate A and the attached 'unknown name plate' on the choke shaft. Both carb have it - more pronounced on the front one. Also the connection between the connecting rod and the fast idle lever (the connection with the small spring) looks very loose. I added three videos to show the current situation. Any help and feedback is appreciated. If someone is wondering about the throttle return spring custom setup => i had to circumvent some fitting issues with the heatshield and Zstory headers. Also the dome screws are not tight on purpose. 1. Connecting Plate A This play results in the nozzle to not fully stay up when the choke is off. I wonder if this play is normal or if the linkage is worn out. I tried to decipher the parts manual (Carburetor L24 (To Aug.-'71)) and don't see any part missing (the 'unknown plate' seems to be 41 - PLATE "D" CONNECTING). The nozzle is able to roughly move 0.5mm. I can only assume that this is not ideal for fine tuning those carbs. If the play is normal would I need to adjust Connecting plate A to mitigate the up and down movement of the nozzle? Or do i need to somehow sleeve the pin on Connecting Plate A? There is also some play where the connection plate A is screwed into nozzle head (longitudinal). I added two videos, one showing the play on the rear carb and the movement of the nozzle on the front one (was unable to film both videos on one carb. But they behave very similar). 2. Connecting rod to fast idle lever My second concern is the slopiness between the connecting rod and the fast idle lever (the connection with the small spring). I added a video showing it on the rear carb.
  5. And will you go for tripple weber or stay SU?
  6. Can confirm from Duisburg - Germany. One Gallon of 'Super 95 (95 RON) today costs 6.77$ Don't ask for the premium juice. Edit: Of course those are our normal prices without any crisis 😂
  7. Hi, can you elaborate a little bit why you still want to remove the head to change the valve stem seals? The video I posted (pretty easy to find for everyone) shows exactly what needs to be done. I did it together with my girlfriend and it was pretty easy. You just need a valve spring compressor tool and some rope (and maybe a new valve cover gasket if yours is done).
  8. I used this video as a reference: worked like a charm for me (with the right tool).
  9. I had the exact same issue some weeks ago in the evening with heavy rain on the German Autobahn. Some people 'happily' flashed at me so i stopped and had a look at a gas station. Bulbs and fuses were ok and since i had no tools with me and had to drive another 100 miles I called the guys from ADAC (german car club - i guess equivalent to AAA) The guy did some measurements and said that most probably the switch had a problem. So we pulled off the steering column cover and had a look. It turned out to be an issue with the big plastic connector (switch was fine). We disconnected it several times and suddenly it started working again. There was definetly some discoloration to the connector and it was filled with (di-electric?!) grease. So maybe someone already tempted with it in the past or Nissan send them out this way? I plan to clean it up in the future. But right now it is working. Maybe you have the same problem. btw. Car is `78 280Z
  10. Great to hear that it is fixed. My windshield is also waterproof again. I used some new precision brand rubber gasket which fits very nicely and looks great, too.
  11. Jupp, did the same: wiped backwards - shat my pants - read the forum - swapped the linkage 180° at the motor - wiped the right way - was super happy - hit the road in hard rain - wiped like a boss - found out that my windscreen is leaking...
  12. I finally had time to work on the car. Valve stem seals are done, new NGK BP6ES's installed + a wideband O2. Mixture ~2.75 rev down showed a pretty rich idle of 11.2-11.4. I went back to 2.5 revs down and now the car is idling at 11.8-12 when hot. Which seems to be inline with experience other people have with SUs on this forum - idling a little on the rich side. I still have to drive a little bit more and check the plugs. And write down the air-fuel-ratio for different conditions. If someone from Europe reads this: The "Ventilfeder-Montagewerkzeug" (valve spring removal tool) from KS Tools (150.0918) works like a charm for removing the valve springs.
  13. Ok, thanks for all the advice. I found some similiar tool available in my part of the world and sourced some elring valve stem seals (original Nissan ones go for 16$ per piece over here...). I will update this thread after the compression test and valve stem seals/spark plug change.
  14. Ok, thanks for the clarification. I thought that this is a generell behavior. I will try with new spark plugs and recdo the carb tuning. As soon as i have time to go to my workshop (sadly not in the next 2 month) will do the compression test. Regarding the sticky nozzle, i sometimes run into the problem that the front nozzle is stuck in the downward position eventough the choke is closed, a gentle touch (sometimes it is doing it by itself) will let it jump up. I had to adjust the choke linkage before, because both nozzles wouldn't stay up. Is there a special method how to bend those linkages to make sure that the nozzle stays up and is not binding? As to the valve stem seals: What would be the "right spring compressor" for the job?
  15. Hi, first of all i want to thank everybody on this forum for always pointing me in the right direction with my Z so far. I am still in the process of learning and understanding the car and trying to identify and fix as many issues as possible. The car is a 280Z with a F54 L28 in it with P79 head and Ztherapy SU carbs (4 screw). Exhaust header is a Zstory Street into Zstory 2.5" full system. The carbs were tuned with the help of a colortune until it showed a bunsen blue (first 1 then 4). This resulted in the fuel mixture nut to be turned a little over 2.5 revolutions down (measured both sides with calipers: 2.7mm down). As mentioned in an earlier post the idle is quite stable around 800rpm. There was some valve ticking from 5 and 6 which disappeared after valve adjustment according to the FSM (cold 0.008/0.010). The car runs fine as far as i can tell (maybe burns a little too much oil => 3/4L on 1300 miles). Revs fine, sounds awesome, but i am still anxious that something is not right and that someday the engine will blow up. Especially the fact that when i remove the oil filler cap and or the dipstick nothing changes. No stumble no drop in RPM, nothing. The valve cover gasket is new, albeit one bolt in the middle of the driver side is missing, but i cannot see any oil leak and hope it is sealing. I checked for potential vacuum leaks but found nothing so far. Also checked the pvc system which seems to work fine. The spark plug colors after some longer highway trip were as follows: 1. dark brown; 2. dry black; 3. wet brown; 4. brown with a hint of white at the tip; 5. same as 6. dark brown. Timing is 10 BTDC, mechanical and vacuum advance seem to work. With vacuum advance disconnected and around 3000 rpm it was at over 20 and with vacuum reconnected even further of the scale. My question now is: what could be the reason and a possible strategy to fix the issue with the non stumbling lady? Any help is very much appreciated.
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