Z-Luke

after reading through the FSM a bit more, I think I may have a bad PCV valve causing excess pressure in the crankcase. I'll look into it. The problem is getting parts for a 1970 240z isn't particularily costly, it also isn't very quick.... looking at 3 weeks at least to get a new valve. Might as well order a new alt, pertronix and tune up kit while I'm at it.

Just a quick update, I went and got myself a can of sea-foam. I warmed the car up to full operating temperature, turned off the choke completely, pushed up on the nozzles to make sure they weren't sticking (the rear carb is notorious for this). I let the vacuum tube suck up 1/3rd of a can in quick spurts while gunning it. This was hard to do, so I ended up turning in the high idle screw and dropping the vacuum tube into the can. Stinky smog cloud! Then I shut the engine off, and while it was still hot poured in 1/3rd of the can in the oil. Interestingly enough, the engine was still "steaming" from the inside when I took the cap off. Not pressurized, but still a-steamin. Then I went to the gas station. The car was having trouble holding idle after ingesting all the sea-man-foam. I poured in the rest of the schmutz and 20 bucks of gas. Took it out on the highway for a nice long 30 mile cruise, and when taking the turn to come back I opened the throttle as far is it would go in second gear. Around 5000 rpm, where the car usually wheezes out and refuses to go further without missing, there were two INCREDIBLY LOUD CANNON FIRES out of the exhaust. It could have been the sea-foam. Not sure. Then I came home and disconnected the breather tube I was talking about earlier. The one that throws the carbs off because of the stinky going into just the front carb. After disconnected that, there was a remarkable increase in power, off-the-line driveability, and smoothness! Impressive increases, in fact. However, when stomping on it in first gear, I impressed everyone in the neighbourhood with my 2.4L 6 cylinder anti-ship smooth bore explosion pipe once more. KAPLOW!!! It was so loud it sounded like it was right behind my head. Anyways, the car still drives fine, not sure what gives with the explosions. Could be the sea-man. Just figured I'd update since I have now put in the additive.

How many miles? ?54,000. Whether there's a one or a two infront of that....I don't want to know really. Was the engine rebuilt, and when? number on the motor is L24-090472, which does not match the vin (XXXX62) thats all the info I have on the motor. If harden seats have not been put in have you used and lead additive? I have not used any oil additives, oil was changed with penzoil 10-30w recently. What color is the smoke? It's a hazy blue, kinda smells like a mix of oil and gas. Stinky. Doesn't blow any smoke when the crankcase breather tube is polluting straight to atmosphere. When was the last time the valves were lashed (check and adjusted for cam clearance)? Was their a lot of adjustment? I did the valve lash a few weeks ago, although I went .05mm too loose (car cooled off before I got the hang of the adjustments). When I did the adjustment, I noticed that sometimes i couldn't even fit a .10mm feeler inbetween some of the intake valves. To me they seemed too tight. When was the last time a compression test was done if a all? I have a compression tester, but I'm afraid of what I might find Any coolant or other fluid loss? If there is, very minimal. Just checked the oil and its full, still quite clean. It smells vaguely of gas, just a hint. Maybe some gas is getting in my oil, or it could be just my messing with carbs. My sense of smell isn't very good, but against the smell of the oil still in the container I bought it in, it smells a little bit of gas by comparison. Blow by would put gas into the oil - seems reasonable? Since you mentioned oil smell what weight do you use? 10-30W Penzoil yellow container. It's fairly cool up here. Dips below zero overnight still. Any engine based mods including electrical upgrades? A previous owner put 3-2 headers on. All else stock - dizzy, points, everything.

I have a question on the blow-by or crankcase fumes coming out of the top of the valve cover on my car. I noticed that the car doesn't burn any oil or smoke at all when the hose is disconnected from the air intake. The amount of 'steam' coming out of the valve cover starts out as almost none at all, to lightly and steadily rising out like a kettle with the lid open coming close to boil. It comes out steady and not in puffs with each stroke. It also steams out the oil disptick tube if you pull the dipstick. When connecting the hose to the air intake, the car noticably idles rougher, and the exhaust gets a little stinky and it smokes a little on throttle. Smells like oil/gas combo, not sure if it's moisture in there too I can't tell. I know that it is just directed into one carb, so I'm wondering if I should try to get it to steam into the middle of the air intake instead where it bends into the front carb. I figure the rough idling is from the stink going into just one carb. I'm okay with this much blow-by (maybe its just leaking past the valves, not sure) because the engine has pretty good snot and the smoke isn't really noticable when fully warmed up and under steady load. I'm just wondering if I should try to evenly distribute the blow by or if I have a bigger problem on my hands. Maybe some seafoam or heavy diesel oil will help get the gunk off the valves. Thanks!

It is indeed a 24C. The battery expert at the local battery store is really good, he knew what it was right away. It fit perfectly, matched the firewall bolt and all.

Hello again gents, I believe my problem is indeed the needle. That thing is so ****ed I think it's throwing the whole works off. Since its so beyond recovery, I decided to try and bend it with my fingers into at least somewhat of a straighter angle. In doing this, combined with a super secret handshake special order of tightening the dome down, I was able to get the plunger to drop. Not perfectly, not quite with a thunk, but more of a 'tink'. The results in drivability are stunning. Now it drives like a car. With the vacuum advance working again, and the carbs reasonably balanced I can drive from a stop with gunning it and making the clutch do all the work. 3rd and 4th pull really well, and it was roaring past 95 mph and climbing before I let off because the whole car was shaking. It's nowhere near perfect, but it's now driveable. Thanks for all the help up to this point. Until I can get all the other upgrades to go on this will do. The only weird thing is that both 3rd and even 4th gear seem to pull harder than 2nd. 2nd just sort of feels lazy and I'm not sure why. It could be that the bent needle is holding back how quickly the dynamics of the fuel delivery adapt to the demands of the engine.

Found the thread Answers are in hya http://www.classiczcars.com/forums/showthread.php?t=31940&highlight=eibach+front+back while I'm at it, I have four tokico blues. Does it matter which are front and which are back? I think two of them might have an extra bit welded onto the end.

While I fully intend on getting the Ztherapy treatment, I can't afford it just yet. It was either that or the suspension for the time being, and I decided the car smashing on the ground on every bump was a greater hindrance to driveability at the moment. That is, until I started messing with the carbs... The needle is not polished. You really have to look carefully to see its bent, but you can see it under careful scrutiny. The piston was NOT sticking at all in the dome before I took it apart and messed with it, leading me to believe it is a re-assembly error. It just doesn't fall freely - I was really careful in keeping the piston matched with the dome. I think it might be a mis-alignment of the piston to the dome. I can only think thats caused by the bent needle?

I've had similar issues with loose ignition wires at the coil/resistor. I've also had that happen with my recent dashpot sticking issues, but if the car drives fine then I doubt its anything to do with that. When I had a battery in the car that couldn't hold a charge properly it also would die if left idling for a few minutes, probably due to voltage drop. I guess the first thing to check is if it's ignition or fuel related...

I've got a new set of Eibachs, and they are pretty light on the destructions. Two of them are shorter and have tighter coils that change to wider near the ends, and the other two are longer and are more linear in design. Also, which way up should I install these? Tighter coils on the bottom and wider towards the top, or tighter coils up top and wider on the bottom? I should be able to get a picture up at lunch.

This weekend I took the dashpots and float bowl lids off the carbs to give them a cleaning. Upon dis-assembly I noticed the rear needle was visibly bent, so I will have to get a new one. However, once the carbs were descuzzied I noticed that the rear vacuum plunger in the dashpot was sticking and not falling freely. When just the needle w/plunger was put in, it would fall freely, but once I put the domes on it would stick. This is causing massive drivability issues of course. I'm wondering what i could have messed up that would lead to the dashpot sticking like that. It does it with or without oil dampening or the dipstick in. Maybe I bent the needle even worse and its causing a mis-alignment. Thanks for the help...

My car came with big meatball 235/60/14's, putting the diameter just over 25 on the drive wheels. I did the math and sussed out that at 3000 rpm I'm doing 66.25 MPH when the stock speedo should read 62.5. However, somebody must have calibrated it because the speedo seems accurate according to my math

Yeah I wouldn't think you need to paint the underside of the car unless you have a lot of candlelight dinners underneath your car. Most cars I've seen have sort of a fuzzy look of think undercoat material on the underside. Sounds like that 3M stuff is the way to go. EDIT: That POR-15 stuff sounds like the $^!#!

Yeah the block itself is rather irrelevant. Getting all the EFI gizmos to work is the biggest hassle. Like Arne says, you basically need the entire car to get EFI working properly. The ECU/computer, temperature sensors, return lines, gas tank and pump, high pressure lines, harnesses, wiring modules, intake manifold, etc. I had to run new wires to the electric fuel pump in the gas tank of my old AE86 when switching to the twin cam engine from the carb'd 8 valver. As for the block, I would go for the bigger displacement L28 for streetability.

What should one spray the undercarriage with after it's done? I am going to do a similar sheetmetal/tube repair job to my floors. I'm just wondering how to seal the bottom of the car up afterwards - bare metal instantly starts oxidizing after all. Rustoleum?

Old carbs can be just as big of a headache as installing EFI and getting it to work. If you're willing to send the carbs off to ZTherapy, then that route is going to be the least amount of hassle for the most amount of benefit. EFI technology itself is far superior to carbs. You get the exact mixture you need for the exact situation desired. Jay Leno recently converted his famous tank-car to EFI from carbs, then turbocharged it. The result was double the power for twice the gas mileage - no wasted fuel. Carbs will always waste a little, but they are so easy to slap on. You can take literally any motor and make it run with carbs. EFI not so much. Since you have aged EFI components I'd stay away from that option unless you really NEED 30 mpg out of your Z, and you're willing to spend money on buying a bunch of new parts like injectors to refresh the whole system. That also opens up some turbocharging options for you. As an added benefit, carbs are much more appealing on a vintage car. They also add that cool sizzling sound of unmuffled intake and combustion coming from the front of the car. Individual Throttle Bodies will get you that too, but you need to spend a lot more moolah and time to get there than you would just sending your carbs to Ztherapy. I'm not advocating either, just make sure you know what you're getting into either way.

I think I had a bad battery. Won't stay above 11.7 volts sitting in my kitchen, at room temperature. Thats after being charged overnight as well. The motorcycle battery thats been sitting in my laundry room for 3 months without beeing maintenance charged at all is still sitting at 12.4

I noticed that my #6 plug is whiter than all the others as well. Is there any way to distribute fuel more evenly to this cylinder? I suppose richening the front carb would be the shotgun method.

you're thinking of the shifter PIN bushing. I'm talking about the regular bushings that hold the neck of the shifter. There's a nut at the bottom that squeezes is all together, and I can't get it off.

I did a search and there's a lot of threads on how to replace the bushings, but my problem is how people are getting the darned nut off at the bottom of the shifter rod. That thing is now fused to the circular rod, and i can't pull out the shifter and replace the bushings with it on there. Any ideas? I heard mention that there is a 14mm flat spot but i don't see it ANYWHERE. Do I have to obliterate the old rubber bushings to find it?

I have a battery drain issue to, thanks for heads up! Whats does your ammeter say now? Mine sits just above the line and what appears to be about +20 amps at 3000 rpm.

Search for a link to the factory service manual, it has brief instructions on how to balance your carbs. There's throttle air screws on each one, plus a balance screw. Without a flow meter you'll never get it dead on, but you can try playing with it. Again, I think running on after turning off the ignition ("dieseling") is a timing issue.

I had a similar problem when I first fired up the car this year. First thing was that I had 2 plugs completely fouled (the two middle ones, 3-4). Then I had to advance the distributor as far is it would go before I had any power off idle. I think my vacuum advance plate and/or vacuum diaphragm is shot. Anyways, try advancing the dizzy and see if it gives you more go out of the hole. Just like you said, my car would just die without enough advance when trying to roll off the clutch. I think you have an advance issue.

did you ever get the hard-to-compress issue fixed? Mine is that tough to move too. Its also like a shock absorber, no way in hell that venturi air movement is going to lift it. I'm waiting for my rebuild kit to arrive before I start wrecking gaskets.

ATF fluid in both. Although one is easier to push than the other. I think they might be binding/sticking due to dirt. I tried putting in a few more CC's of 10-30 (datsun manual) in the rear carb but it's still easier to push up than the front. I don't have any way to measure effort, but i'd say it like lifting a 10lb dumbell with one finger at the front and less at the rear. I'll be ordering that Just SU's DVD real soon Bruce!