MariaAZ

DJ - where are you? There might be a local Z club around with members who could help you check it out.

AWESOME! That's exactly what I needed to see. I'm the type who needs to exactly why something has to be done a certain way, and as they say a picture is worth a thousand words. Now I don't feel so apprehensive about removing the head (well, except for maybe a broken bolt or two!) Thanks a million

I don't see any oil when I open the radiator, but the coolant level DOES drop. However, a good portion of that may be due to the water pump leak we discovered! I haven't changed the oil yet, so no opportunity to see if there's water in the oil pan. kyteler, if it wouldn't be any trouble to scan that diagram, it would be GREATLY appreciated! Even if, by some wonderful chance the head wouldn't have to be removed, I still want to know how to do it for the time when it HAS to be done.

We took the '73 240Z out for a brief run yesterday. Hubby (whose Z it is) is already challenging me and my '74 260Z to some friendly competition. The first few times I tried starting it, it blew huge clouds of white smoke from the tailpipe. However, after running for awhile it gets better and the water vapor get less noticeable. Cylinder 4, which has very low compression, has a sparkling clean sparkplug, a sign (I hear) of water leaking into the combustion chamber. I haven't yet tried retorquing the head bolts, suggested in an earlier post. However, I am preparing for the eventuality of pulling the head. I checked the gallery to see if I might find a photo of where to place the hardwood wedge. This is the only hesitation I have; I don't want to have to deal with resetting the timing chain. Does anyone have any photos or maybe a sketch of exactly how to wedge the timing chain?

What about a daily driver? The early '74 260 is my daily driver. I do a lot of freeway driving, about 80 miles round trip once or twice a week. The rest is standard surface stop-and-go. I'd like to make her faster, but I have to watch the mileage at least somewhat. Would a 5 speed be beneficial for what is purely a street car that may someday have some performance mods?

This has been my lucky week for Zs... I found out what the problem was with the Z. The dist was bad; swapped one out from my donor Z and the car that's been sitting for over a year finally started! That leaves only one non-running project car (a Roadster) left to tackle.

I just got the good news from the mechanic who I took my 260Z to in order for him to get her to pass emissions. I have a pass test result and can now get tags for her! I'm so excited, I can hardly wait to pick her up tomorrow (the shop is a good 30 miles away, and hubby & I have to share a car so there's no way to get her today.) It will be interesting to see how different the ride is when someone who really knows what they're doing has a turn at balancing the SUs.

While waiting to have the 260Z tuned up to pass emissions, we decided to toy around with our non-running '73 240Z. Although we bought it non-running, we were able to drive it home from the PO's house after spending what seemed like hours coaxing it to start with carb cleaner shot into the carbs. That was about a year ago, and the last time it ran. Now, it just cranks & tries to turn over. Yesterday, we pulled the carbs off of our (now once) running '71 240Z and put them on the '73, as the carbs that were on have seized nozzles. Still nothing. Today, we swapped over the coil & ballast resistor & bought a new condenser for the distributor. Earlier, the dizzy received new points & rotor. New plugs & wires rounded off the project and STILL no start. I posted on this project in December, the compression numbers seem to indicate a new head gasket. Our next step would be to swap out the distributor from the '71 as well, but I just thought I'd check here first and see if someone can maybe give hints on what else we should look for.

In AZ the car's age dictates the testing it goes through. Newer cars are subject to more rigorous testing. My Z only has to pass HC & CO at idle and load. She does great when on the dyno & tested, but just keeps failing the HC at idle.

Victor, I have this really sinking feeling that something was used to fix the nozzles in place. I've tried using a punch from the top to drive the nozzle out, but it wouldn't budge. There is absolutely no connection from the nozzle to the carb, and I can't even rotate it. I think I'm just going to take it to a machine shop and see if they can maybe drill it out. I'd sure hate to a) ruin the nozzle bases for core and ruin the carbs, but at least I now know why we could never get the Z to start And yes, this is Charlotte... I use my middle name online because it's shorter as a screen name

I am having MAJOR problems getting the nozzles out of an SU carb. The carbs are the ones with the large flat mixture nut that has the metal stop mounted to a wide metal tab. There is absolutely no movement in the nozzles (no wonder the car never started!) and they don't budge at all. The other set of carbs I replaced the nozzles in were a dream to work on; loosened a screw, remove the fuel line and the nozzle slipped right out. Not these babies, they aren't going ANYWHERE, up OR down. Am I missing a step? Any idea on how to get the nozzles out? Thanks in advance.

I felt compelled to check in on this one, since it is stories about the "better half"... My husband's father was a Datsun fanatic. He loved everything Datsun, and according to hubby could fix just about anything. Well, my dear spouse inherited his father's passion for Datsuns, but not the part about working on them. My first love is Datsun Roadsters, but hubby can't comfortably navigate under the hood. I'll give him slack on that, because he is tall and Roadsters are short and very compact under the hood. So, trying to get hubby to feel involved and making the weekends spent under the hood more a "couple" thing than a solo act, we bought a non-running '73 240Z. Perfect height, lots of room under the hood. Heck, I could practically crawl in the engine bay to work on the thing! Didn't work... he just isn't interested in wrenching. I was good and didn't touch his car though, so we recently bought a 260Z for me to play with, then recently a '71 240Z. Hubby is very supportive of my hobby though. He'll keep me company while I'm working on cars, and help when I encounter nuts & bolts that I can't get loose. He bought me an air compressor and all the toys as well as tons of tools and equipment. He's gamely trudged along with me through junkyards, though I lure him there with promises of getting goodies for his '73. Now that I'm getting the 260Z running, I let him take it for its maiden voyage on the freeway, and he had a blast. Now he's excited about getting the '73 up and running, so there might be some hope for him yet.

I FINALLY got my 260Z on the road... what a feeling! I bought a rebuild kit for the round tops from ZTherapy & followed the video on installing the stuff... adjusted the carbs and ran her through emissions just for grins & chuckles. I passed 3 of the 4 tests with flying colors, and with the emissions stuff removed or disabled. The 4th test, HC at idle, is still pretty high but the guy at the testing station said to recheck timing & idle setting. I'm taking the lady to a local mechanic who is well known for his talents at getting Zs to pass emissions; I'm letting an expert take over at this point so I won't waste $$ paying for testing until I get it right. After the emissions test, I richened up the carbs so she would run better. There's no backfire except for a noticeable pop when shifting gear, especially at higher speeds. I searched the boards but couldn't find reference to this particular issue. Is this part of the normal backfire at decelleration, or am I running too lean?

I KNEW there had to be a reason I just couldn't get the 260 airbox to work on the SUs! A couple of pieces were missing from the mounting plates, so I just removed them and popped on an early airbox that I happened to have lying around

Actually I did indeed post that the Z will have to pass emissions. I've spoken to a few local Z sources who have said they were able to pass with the emissions stuff removed. I'll see what happens, as I'm getting a pair of rebuilt SUs on an early 240 intake manifold that has the smog stuff blocked off. If it can't be persuaded to pass, I'll still have the original intake manifold that still has all the smog "stuff" attached. It amazed me that the inspectors at the emissions testing facility didn't even pop the hood open. They just made sure I had a gas cap.

I am debating on whether or not to leave the anti-backfire valve on the manifold of my 260Z. The throttle linkage has accomodation for the valve. What do I do with this part of the linkage if I decide to remove the valve? Also, does this valve really do what it is supposed to do? I am stripping off all the smog stuff, but if this valve actually reduces or eliminates backfire on decelleration, I don't mind keeping it. Thanks in advance

I was not able to find the thicker spacers yet, but i DID replace the studs so I could get the carbs on. After getting everything plugged or disconnected, I fired up the ol' Z and she runs like crap. The engine surges on its own, like someone is rhythmically stepping on & releasing the gas pedal, so it's virtually impossible to get the carbs balanced. I was told by a mechanic who works a lot on Zs that the carbs probably need to be rebuilt, as the backfiring (which I can get rid of by richening the fuel mix) and surging sound like worn internals. I've located a pair of rebuilt 4 screw carbs that will be mine when they are completed in February, so I guess I'll just have to wait. In the meantime, I still haven't figured out how to completely remove the EGR valve from the manifold. It doesn't look like it can be completely unbolted unless I have something fabricated to cover the inlets & with a mounting bracket for the accellerator. Also, is there any benefit to leaving the anti-backfire valve? If I remove it, do I just let the connector for it on the throttle linkage flop around freely?

I have a set of 3 screw round tops in our '73 240Z, and have just completed the swap in our '74 260Z. I purchased the linkage for the '74 from Motorsports and it works great. However, this linkage will not work with the round tops in the '73; I tried it. The difference I noticed was in the metal tab that controls the rear carb; it could also affect the front carb, but once I saw the back wasn't going to fit I didn't pursue it any further. The length of both linkages is the same. I can try to get some digital photos if someone needs them.

I've installed '72 round tops & air box on the 260Z. Arizona requires all cars built after 1966 to be emission-tested. I've removed several components of the smog equipment, trying to keep as much on as possible (which isn't much with the '72 air box.) My biggest concern is getting the numbers low enough to pass emissions. I checked past posts & have found reference to lower CO & HC numbers after the carb conversion. Are there any AZ 260Z owners here who have stripped off the emissions stuff & still passed the smog test?

I've got the SUs on the 260Z, and would like to know if I'm doing everything right so far. I'm debating using a different air breather than the stock one. So far, I've: Connected a water hose from the outlet near the firewall to the outlet on the thermostat housing (used to go through the flat top carbs) Would it be better just to plug these outlets? connected the hose that comes from the vacuum advance on the dist. to the front carb. This also seems to go to the throttle opener valve There were a few broken hoses when I pulled off the air breather, and I'm not exactly sure where they all go. The hose with the PCV valve looks to go to the air cleaner. There's another broken hose at the cranckase. I'm suspecting that perhaps these two should be connected with a hose? I still have the air pump, and don't know what to do with the hoses for it, either. I don't mind keeping it, if it can be made to work with the earlier air breather.

I'm still working on getting the carbs on, having just discovered that NONE of the auto parts stores carry metric studs. I can order them from the local Nissan dealer but it'll take about a week for them to get here. It's sooo frustrating that I can't find a $1 metric stud cash & carry! However, I'm intrigued by the ground pepper & whisked egg fixes. If I use them together, will I have an omelet? Pass the cheddar cheese, please

There are isolators on the manifold of the size you mentioned, but the studs are still too long. I've seen photos in the gallery of manifolds with thicker isolators. Maybe that's what I'll need. Thanks for the tips on how to stop the freeze plug leak. It will only be a temporary measure; I just can't handle the thought of yanking out the motor just yet!

I took off the flat top carbs on my '74 (hubby won't be too pleased that I've "rendered yet ANOTHER car nonrunning) with fairly little difficulty. In trying to place the round tops on, I realized the studs are a tad bit too long. So much for getting the new carbs in before he gets home from work! What is better; replace the studs or use a gasket as a spacer? I have the plate to allow me to use my stock air breather, so for the time being I won't have to deal with what to do with every single hose. However, I DO need to know the best way to deal with the hoses that are no longer used. Also, which hoses go on to the nipples at the top of the base of the round tops? On another note; I discovered that the freeze plug on the back of the engine by the firewall is leaking. Not a lot, but enough to puddle a bit under the car. I don't really want to pull the engine yet (note husband's probably reaction to a simple carb swap above; imagine me saying "honey, let's pull the Z engine this weekend!") Is this something that can wait a bit? Any "band aid" efforts I can take? Thanks in advance

Mess or not, it's gotta be done. I just wanted to make sure I wasn't seeing things or going nuts! :stupid:

I have my round top carbs & linkage for the '74. Doesn't look like it'll be too difficult to swap the flat tops out (keeping the intake manifold) In preparation for the swap, I started to drain the rad. Looked for the draincock and couldn't find it. Using a mirror, I located what looks like a brass nut with an allen wrench center where all the diagrams show the drain should be. I'm used to the drains where there's a butterfly-shaped "spigot" that you turn to drain the rad, and all the diagrams I've seen indicate this is what I should find. Any idea on how to drain this darned thing? :disappoin