zeiss150

So, I haven't been on this forum in a few years but I'm glad to be back. I have a 72 240 with a 2.8 and a 5 speed. My diff is the stock 240 ( I believe its a 2.70) so my drive train is a bit of a "hybrid". On to the problem... When I accelerate, or down shift, basically whenever there is torque on the drive train i hear a sharp "crack" and then some "scratch, scratch, scratch". coming from the rear passenger side When I look under the car I don't see anything "odd" no metal wear. I'm wondering if its the needle bearings in the half shafts. But what is the "Crack" sound? I replaced the differential mount about 7 years ago so I don't think that's the problem. I'm thinking about pulling everything from the drive shaft back and replacing it... big job... lots of time... grrrrrrr. Any suggestions would be great! Thanks, Matt-

I used a 5 speed from an 1980zx. Its been working great. I know there are different ratios with different years but I think the main difference is the borg warner T5. And then of course the differential ... there is a bunch of choices. I think the differential makes a bigger difference... but, what do I know :-) Good luck

I know there is no accelerator pump so pumping the peddle alone doesn't do anything to add gas but the pumping action gives it a big gulp of air which will suck more fuel through the carbs than at idol alone. At least thats my theoryLOL my Z wont start unless I do the pumping thing if its in the 50's (thats cold for us in southern california). I stoped using the choke cause it caused more problems than it fixed, and I just didn't feel like fixing the choke problem. Matt-

Ok so I finaly go around to trying Daves fix (cutting the return springs) and it seems to have fixed the problem! Now it runs a nice solid 850 rpm (after setting the idle) If I tap the peddle it still stays at 850. Nice job Dave! I took off 5 turns off the bottom of each spring, its a pretty easy fix. Its always the simple things that seem to frustrate us. Matt-

you don't have to give it gas when you start it cold in the morning? I always have to give my Z a little shot from the peddle when I start it. If I just start it with my foot on the break It wont get enough fuel into the engine to start, it'll just sort of sputter and die. Now keep in mind I don't have to pump it (unless its cold in the morning, below 70 F) just a tap on the peddle and vrrrooooooom. if you have to pump it mabe your float bowls are draining ... but then that wouldn't explain the easy cold start. Are you using the heat sheild? It could be getting the fuel lines to hot and causing problems? I hope this helped. Matt-

I checked on ebay and the 95 eclipse turbo injectors are 450cc. but its ebay so take it for what its worth. I hope this helps. Matt-

So I just put together my P90 head (rocker, lash pads, cam) its off the car right now and I was setting the cold valve lash .010 exaust .008 intake. so thats all set, my question is why are hot valve settings bigger than cold. with the cam hot, the metal expands, making the cam closer to the rockers so then why would the gap be bigger than when they are cold set. shouldn't the hot setting be the smaller gap and the cold be the larger gap. What am I missing? I've hot set my Valves on my N42 several times so I know how to do it, but this is just bugging me. Thanks for the info, Matt

Thats a great Idea Dave. Why didn't I think of that. It would pretty much do the same thing as taping the peddle. I'll give it a try. Keep the ideas comming! Matt-

thanks for the posts guys. I have also taken all of my smog stuff off. I plugged all of the holes on the ballance tube so there is no vaccum leak in that area. I've also replace the balance tube gaskets. I have a rebuilt ZX dizzy and the vaccum advance is working as far as I know. It almost seems like the problem is because the butterfly valve in the SU doesn't go compleatly closed, so when you tap the peddle the quick up down motion makes the butterfly valve "close" a tiny little bit more. Stupid idea? If anyone has anyother ideas ... Bruce... please jump in. Matt-

Hey guys. I've been fighting this problem since I got the Z 4 years ago. The Z idles at about 850 RPM's wich is great, nice and smooth. once I start driving around the car will jup up about 150 to 200 RPM when I come to a stop light. If I tap the gas peddle, the idle will slowly (in about 1 to 2 seconds) drop back down to 850. the Z runs smooth as a top at both RPMs but I would like it if it were a constant 850. Is this a throttle shaft problem? the shaft bushings have never been redone. The chrome on the shafts is worn. there is nothing binding or hanging up in the linkage, so thats not the problem. My carbs are supper clean I pretty much rebuilt them with the exception of the throttle shafts. So What do you guys think? Thanks for your Help, Matt- P.S. I came accros another Z guy and he said he was having the exact same problem.

WOW!!!! what a find. that Z is almost perfect. Just replace the set skins and you should be awewome! Great job in keeping the Z alive and on the road. Rock on. Matt-

the bolt just broke off? If thats all that broke then just drill it out and have a new one welded on. I don't remember my window regulator that much so forgive me if its more complicated than that. I hope this helped. Matt-

Just my 2 cents but ... I would go down to the junk yard and pull a new motor. There could be all kinds of problems trying to fix the old one. Dont feel bad either I rebuilt my L24 by myself and it blew up. It wasn't really my fault though the guy that did the head (E88) rebuild did a crappy job. He replaced the bronze valve seats with SS seats but one of them wasn't in good. I was on the freeway and it poped the valve seat which hung the valve down and made contact with the piston and the rocker arm came off and all kind of horrible stuff. sooooo I just pulled an L28 from a ZX, and rebuilt that one myself and its running strong!!!! I wouldn't spend the 3k to have someone build it because stuff can always go wrong and you can get a junk yard engine for about $500 (califonia $'s) Besides isn't building it yourself the whole point of having a Z. Good luck with what ever you decide to do. Matt-

well we know that your Z has had 3 colors in its life time .... at least! Thats ok mine was five differnt colors, all at once. Primer gray, primer red, silver, blue, and green. You should have seen me driving down the road. Have fun and welcome to the club! matt-

I second the idea of using the 280ZX electronic dizzy. Thats what I did and it works great. Go to a junk yard and get a dizzy from a 79-80 280ZX and make sure that the module on the side of the dizzy says E12-80. If it doesn't it will have E12-92. I used an E12-92 untill I could find an E12-80 and it seemed to work just fine. Make sure that the magnet isnt broken in the dizzy (good luck with that one). My magnet was busted but I just put it back together and it works fine. If you switch to the electronic dizzy I highly recomend doing the 70amp ZX turbo altinator switch as well other wize you will burn out your punny 40 amp altinator in about a month. All of the mods I just told you about are gone over in great detail here... http://www.geocities.com/zgarage2001/engine.html I hope this info helped you out. Good luck and let us know how it goes! Matt-