neoxman

Thanks for the tip Dave.

I've posted this on another thread but could be helpful: http://www2.zhome.com:81/ZCMnL/240ZTSignalMod/turnsgn1.htm

it's great what you're doing here but have you guys considered a real fix for the turn signal problem? A rewire diagram was made by someone on some forum a while back but it was not super clear how to fix it since he used a 78 switch on his 240z. Anyways sounds like using a relay is the ultimate fix, just wish i could get my hands the parts. here's the rewire instructions: http://www2.zhome.com:81/ZCMnL/240ZTSignalMod/turnsgn1.htm

That was it... i unplugged both the white and black wire going to the solenoid and used a bridge wire (aka screwdriver) between the terminals, and it kicked over. Turns out the black connector was a little grimey and oxidized. I must have bumped it when removing the AC, just enough to give a poor connection. Thanks for the troubleshooting help guys! Best regards

Battery is fully charged... i could try brushing up the terminals and tightening them down, but it was running fine as my daily driver until i messed with the AC... must have pulled something ... every once in a while the starter won't start... however it only happens once and starts up right after that. could it be a bad relay? I don't know anything about the fuseable links but could that be a problem too?

I removed the AC in my 1973 240z and now it won't start. I can hear the relay on the passenger side "clicking" but starter doesn't crank. Any ideas? Rob

I'm thinking about going EFI. I like the SUs and think they're great for performance but I'm a young-enough guy still and enjoy the precision of EFI. I also like to tinker with data and computers. I was wondering if any of you guys have converted to EFI and what challenges you may have faced along the way. Some goals of mine would be to: 1. keep costs down (2500 for a kit and 2500 for TEC-II ECU is a little much - is this thinking realistic?) 2. Convert the L24 now but plan to go L28 later (maybe stroker) 3. plan to use a custom made surge tank 4. plan to daily drive the car and track moderately on the weekends Can i put the kit together with all aftermarket stuff or is there some junkyard items that are worth getting.

that's pretty good beandip... yeah I may just be in over my head I forgot to mention i checked the needles and they're both N5 needles but the ink was wearing off and i couldn't find these in a list of needles for the z.. including brit. neeedles. The problem is the car is in really good condition other than these freak carbs and was well maintained prior to sitting for 5 years. Don't get me wrong i think the SU's are an amazingly simple design, it's just the mixed bag i have to work with could be more than a weekend tinkerer can handle. I just want to get it running smoothly enough until i go much bigger engine-wise and put maybe a rebello motor in it. so that means carb change too. I feel i'm 90% there but might have to go back and check the front float level before re-adjusting idle mixture. Front as i cannot set the rear float level. I'll try some of those tips you guys gave me to eek out that last 20% out of these carbs.

I tried 180 deg. turns and it went real lean so it must mean 360 deg. turns. I think i've got it closer but it's very hard to tell what is a good fuel mixture.

After a full weekend of removing and disassembling the carbs i cleaned everything and put it all back together. Had some problems because the rear float bowl has a bypass fuel nipple or extra nipple and i thought that was for vapor relief. I hooked up a hose to pipe it into the air cleaner and ended up with an air cleaner full of gas! Good thing nothing bad happened. I plugged that extra inlet as had been done when i bought the car. Still not understanding the Idle nut adjustment. Is one turn 180 degrees or 360. I read somewhere the base adjustment 2 turns is .060" in depth from the top of the bridge for the jet nozzle height. Thats almost a 1/16" if i'm not mistaken. Mine at 2 360 degree turns looks like 1/8". Thanks for your guys help so far. btw runs much better after the rebuild and 20wt oil.

So 3 screws hold down the dashpots, and I was successful at getting the carbs tuned up. The balance was way off, and now it's a lot better. I still think it could run better. I floored it to see how well it would rev and it gets up to 4500 nice but around 5000 it's struggling and feels rough and and it can't rev any higher than 5200 - 5400. But definitely is much smoother driving now that it's synced and the throttle was evened out. So the part of the adjustment that threw me off was after I set the idle nuts to 2-1/2 turns and set the throttle adj. screws even... the instructions say: "8. Turn in or out front and rear idle adjusting nuts simultaneously by each 1/8 turn until the fastest and most stable engine speed is obtained." My engine speed did not change when i turned the nuts. Is it supposed to go up or down? i think i ended up at 3-1/2 turns out.

Thanks for all the input guys. I will try figuring out if the dashpots are 3 bolt or not and I'll definitely try tuning it again. So far the most confusing thing about the carbs has been the number of adjustments and confusing use of terminology refering to the different adj. screws on these carbs. Some people say "idle screw" and that is confusing because it can be the idle mixture or the fast idle. Now I have those straightened out. This site had some good diagrams: http://www.teglerizer.com/sucarbs/techtip6.htm But even their diagram had one less balance adj. screw than the Z's SU's. I'm still wary of the rear carb and possible jet difference. Do you guys think the float bowls are different volumes? I don't know carbs so i'm not sure if that would be a problem. I will let you guys know when i do the adjustments. Thanks again!

Thanks for the quick reply Gary. >>>What do you mean fixed float ? there is no fixed float on a SU. I'll take some pictures, but float pivot has a brass pin through it but no arm to bend to set the level. >>>As for a mixed set , it should be fine as long as the needles are the same and they are working properly. I hope the needles are the same. Are the labeled if you remove them? >>>You said that you balanced the carbs with a air flow meter and adjusted the mixture now it has a 3K idle? Sounds like you need to go back and adjust things properly. This engine should idle at 700 RPM . I've been reading up on the adjustment and I know now i've been adjusting this the wrong way. but even before i messed with the carbs it was exhibiting the surge problem. >>>What did you set the timing at ? 10 deg at 700rpm. I'm not sure what the best timing should be with my setup running 91 octane. >>>Also the new Dist what is it, what kind of ignition are you using ? I purchased a new Euro Distributor from msa and using the stock coil. NGK BPR6ES plugs and custom cut Accel 8mm wires. All gapped including the breaker point in the dizzy. >>> The parts you have circled can be removed as long as you don't have to stand a emissions inspection . Great, i don't need it inspected so off they go. >>> One way to look for a vacuum leak is start the engine and take a spray can of carb cleaner and spray it around the intake manifold and suspected leak . If there is a leak the engine will change RPM when the spot of the leak is sprayed . DO NOT USE START FLUID FOR THIS. I did this with carb cleaner from gumout... i got some vapors around the carb inlet and idle went up slightly. but other than that my preliminary spray didn't do anything. I will do a more extensive test later. >>> What is the casting # on the intake manifold ? E88 head is also E88

I bought a 73 240z with SU round top carbs. It hasn't been running very smoothly all the time. It's hard to rev past 4500 and when it gets into stop-and-go traffic, where it is a little hotter it starts to surge and won't go away until i floor or get out of traffic. I've been reading the forums and I completely replaced the ignition except the coil. It's much smoother revving with the new ignition but i've tried adjusting the carbs with a unisyn first then setting the mixture and now i've developed a high idle and while driving the idle won't fall below 3000rpm. I've also noticed in this process that i've got 2 different round top carbs. The front is a 4 bolt float bowl, and the rear is a 3 bolt flow bowl with a fixed float. I'm wondering if this is the problem or if there is a vacuum leak. I have some pictures: Front Carb Rear Carb Parts I'm not sure of... do i need this? I also topped off the carbs with 20wt oil.