4zcar crazy

I wondered about using old condensers for a tranny cooler. Great job. I assume Vancouver Island is "the Vancouver Island" BC? We have been talking about going to Vancouver for a long while, and I really like Vancouver Island. Otherwise, are you ever a little south of Tacoma or Seattle? Did you see me question about storing the automatic transmissions?

I was asking about he storage of the automatic transmission because I used a TH350 from a 1971 chevy that had sat for 20 to 25 years. I did replace the fluid and filter first and it worked fine as far as I could tell. However, soon after it started to leak fluid out of the shift lever and other places. I did replace the front and rear seals (they have not leaked). I loose a lot of fluid. Oh well, I tried.

How do you know a used automatic will be ok if it has been stored for years? I heard that it must be kept full of fluid so that the seals do not dry out (probably overful). That was another reason why I was thinking about rebuilding the one I have, but it also sounds like I would have to get a new torque converter since the old one is contaminated. Not to mention some of the parts like the torque converter are very very expensive. I like the idea of replacing it with a used one.

Thanks. I see your points. So, I think it would be much better to discuss purchasing a used one from you. It does sound like it could be much more reasonable. Besides, I was hoping to keep the car as stock as possible. As you have noted, the transmission I now have is full of burnt ATF (and alot of particles.) Towing and downshifting with and automatic must overheat the automatic and OVERHEAT the automatic transmission. Now I get it even more. It's just hard to know when a auto is overheating since there is no temp gauge. I have recently added one to a GMC crew cab with a 4L80 because a mechanic (also) said it was the only way to monitor the tranny when towing loads. He also installed a large cooler and fan for it. The prior owner was told the transmission was shot. So far it is working fine after the previously mentioned modifications and a VSS replacement. I am not exactly sure what the biggest cooler is because there are so many to choose from. Do you go by BTU's? Is there a better location for the cooler? Does it help alot to have a fan?

Or maybe I should just change it to a manual transmission? Is that more work than rebuilding the auto? and is the auto from that time period worth rebuilding?

I have a 260z early 1974. ONly have one gear. No reverse either. Car sat for who knows how many years in southwest WA. Fluid not clear and pieces in pan. I want to rebuild. It has a long tail shaft (over 1 foot long). Not sure if original but rest of car is close. I will use service manual and the advice here. Any idea were to get a rebuild kit that works and a flexplate and any other parts I will need?

I have a 1977 280z 2+2 that i got about a year ago. Ive been going through all the problems with the car since i first bought it, i fixed the starter system, fuel injection sytem, fuel injection wiring sytem, fuel pump, fuel lines, air flow meter and then most recently i put new valve seals in because it smoked. Now i have another problem that i cant seem to solve on my own: while driving, when i push the clutch in or put the car in neutral, the rpms go up to about 3000 and stay there until the car is slowed to around 5 mph. It happens no matter what gear the car is in, and Its not the throttle linkage because I had a friend sit on the car fender with hood open while i drove slowly. I sped up past 10 mph in first gear, so the RPM's were at about 4000-5000 RPM's, and then as soon as i pushed in the clutch the idle droped down but only to around 3000 RPM's. The throttle linkage was still at idle position, which he checked manually while the car was moving. Then when we slowed to below 5 mph, idle RPM's dropped back to normal (800ish). It almost feels as though the car is trying to keep itself moving, even putting the brake on or the E brake on while the car is moving does not change the problem. The RPM's only drop once you get the car under 5 mph. I thought for sure i would have this problem fixed because i just pulled the motor out of the car to fix the valve stem seals. I took everything off the outside of the motor including the tranny, cleaned everything, and then replaced all the gaskets and re assembled everything. i even switched the old 4spd tranny for a better 5spd one i had laying around, and yet the same exact problem still persists. The only things that i can think of that might cause this problem are the computer, air flow meter(Which i replaced), the AAR(auxilary air regulator), or the BCCD, or something else?? Anyway any help would be greatly appreciated! Thanks!

I sat on the car fender with hood open while someone drove (slowly). Once the car speeds up past 10 mph, the RPM's would go up to about 4000-5000 RPM's, and then as soon as the clutch was pushed in the idle drops down but only to around 3000 RPM's. The throttle linkage was still at idle position, which I checked manually while the car was moving. Then when we slowed to below 5 mph, idle RPM's dropped back to normal (1000ish). It almost feels as though the car is trying to keep itself moving, if you put the car in second gear and speed up to around 35mph and let off the gas the car doesn't slow down but will continue to drive at the same speed, sometimes it will even speed up. It's possessed.

Hi again. Another strange problem while driving the car.... the rpms go up to about 3000 and idle stays there until the car is slowed to about 5 mph or so. Its not the accelerator as far as we can tell. Putting the brake on or the E brake does not change the problem. Once we slow down to about 5 mph or so, the idle drops from 3000 to 1000. Its really weird. ANY help on that one. The car seems to be running well. I still need to make the idle or mixture spring adjustments and a few other fine tune items. But, we did adjust all valves and bumped the spark plugs up from a 6 to a 7. That seemed to help the motor b more responsive (quicker under acceleration) and seemed to have a little bit better power (not much). It is running well. Still have to replace the valve seals. Will try that as soon as we can. Seems to be tolerable on the smoke, much better than after we first got it running (and after the fuel pressure fix).

Thanks. I start putting the rope in just a tiny bit before TDC and then fill cylinder as much as I can with the rope. Then turn the motor by hand to tighten the rope in the cylinder so the valves are tight. That makes sense. We can do that. By the way, we have driven it a few more times for 15 to 25 minutes at a time. The motor is definitely not smoking as much. It looks much better. Still smokes but in a tolerable range now. So, hopefully replacing the valve seals will help more. Sounds like an interesting repair.

As for the 1/4" nylon rope into each cylinder. I do this at top dead center for each cylinder and I stuff the rope in until it's tight and cannot get anymore in? Then pull it out and move to next cylinder? I can totally see the reason for the big knot. So you basically do one cylinder at a time remove old seal, replace with new one, put springs rockers and etc back together? Oh! the cold start valve must be working correctly because if i unplug it, it is hard to start especially when the motor is cold. I also picked up some NGK BP7ES plugs when it was having the rich running problems. I have BP6ES in the motor now. I will try them after driving it more and getting the motor cleaned out some. Sound ok?

For the first time since starting to help kid on this project 9+ months ago (off and on), I feel like this motor, electrical, fuel, etc will work. There have been many hurdles not mentioned. It finally ran pretty good yesterday, and while it still smokes (even a small amount at idle), it seems to be much less and maybe tolerable until we can start the valve seal project (thanks a ton for the advice on it) and exhaust leak (exhaust manifold bolt broken). I am going to pretend that the adjustments suggested and the lucas/? miracle oil/gas additives helped LOL. We will continue to try driving often rather than letting it sit until it is licensed to be on the road. We drive it on our little country gravel road now. It has more power than ever and stays running.....yeahhhhhhh! Now we can get back to the other suggestions on some fine tuning too. And go over brakes and coolant again to finish. Thanks so much everyone.

ahh. That sounds like something we can do with a little practice. And I like not having to remove the cam. I assume I still have to support the valves? Thanks.

Alright, I will warm it up and let it set for 10 minutes and start it up. If I get a big cloud of blue smoke, then it is probably just the oil seeping past the valve seals into the cylinders. And the seals are removable without removing the head. Cool. I assume I have to just put rope in each cylinder so that the valves don't drop into the cylinder? Is it fairly straight forward to remove the cam shaft and the timing chain and reline them back up?

Back with more on the smoking z car. Finally found the problem with the fuel pressure. U all were very helpful again. It was the return line. It was clogged about a foot (metal line) from the rubber line that goes into the gas tank. Totally plugged with black goo and some rust. Got it unplugged after many hours. yuk. And the pressure now reads 36 to 38. No more gray smoke! and it runs without fouling the plugs from being too rich. Yeah. Made a minor adjustment to timing and it has some power now. The bummer part.... now the smoke is blue. Probably was blue and gray before. It's not bad when it's idling, but under acceleration is much more. And upon letting off gas, u get a momentary cloud out the exhaust pipe. Any ideas....maybe valve seals if I m lucky. Its too much blue smoke to drive it and not get some not so nice gestures from the folks behind the exhaust pipe!! I am going to try and adjust that mixture? (screw) on the lower corner of the MAF back to where it should be. And I need to adjust the (what we thought was the idle mixture screw) -- the big 2 inch spring thing with an adjustable screw in it on top of the air inlet tube (just above the throttle sensor). I notice that the prior owners had broken the exhaust manifold bolt on back of motor (last one). So, we probably need to remove the top end of motor eventually anyway. Any suggestions. Thanks for all the help.