FuerGrissa

I just bought a 1990 300ZX sight unseen from halfway across the country and in order to forgoe the month it would take to get it shipped decided to fly up and drive it back home. well suprise suprise now im stuck halfway home but at least i got a brother in the area with a garage i can use. as background its a 1990 300ZX TT manual. the only things i know for sure that are done to it are new rings and rod berrings, new HKS intercoolers and some type of "Stage 3 racing clutch" as the previous owner described it. anyways it has an interesting problem that has me a bit baffled. after you have been driving the car for over an hour or two and it gets good and hot the clutch will slip sometimes, ie: i was coming up an on ramp in 3rd shifted fine, put the pedal down a bit and it started to pick up speed, but then lost all power transfer to the wheels and just revved out untill i got out of the gas and kinda babied it up to speed. when it started slipping there was no vibration, rattle, sound, smell or anything. that was the first encounter. after driving for anout hour or so i stopped to get gas, when i parked the car it was driving fine, when i came out started it up and went to pull out on the road in 1st gear it did the same thing, the clutch was fully out but it wasn't engaged all the way or something, wether i revved out the engine, or tried to baby it didnt make a difference, as far as the power getting to the wheels it might as well have had a lawn mower engine, and it was the same in every gear, same thing, no sound smell or vibration when it went out or after. anyways i pulled into a garage but they were closed so i sat there for about an hour and a half, decided to give it another go and suprising enough it worked. so i got back on the interstate and went as far as i could untill i got stuck in stop-and-go in new jersey. the car seriously does not like to go under 5 mph lol, so after riding the clutch for a good 30 minutes it went out again, i got it down and off ramp but lost all power transfer all together at the bottem and couldnt even get into a parking lot, I wated about and hour and it still wasnt cool enough to get off the road, but with a good push i was able to nurse it into a parkinglot where i waited another hour and a half before it was good to go again. long story short i made to to my brothers house in PA about halfway home and if anyone can help me diagnose the problem so i can fix it faster and cheaper id very much appreciate it.

ohh yeah, and the new "Racing Clutch" has under 1k miles on it.

*edit* on another note even though the car has given me so much problems i am infatuated with it, its everything i've dreamt of since i was 16.

Spongerider

It could be a number of things but try these first since it's free.

Re-bleed your your clutch system and look for signs of leaking around the master and slave cylinder.

if that looks ok then visit this site and adjust your clutch.

Specialty-Z Clutch Pedal Adjustment

If the clutch was not broken in properly then that could be the problem as well and would need to be replaced.

__________________
http://www.socalzcrew.com/gallery/ma...serialNumber=3

WILDFIREBLAZING

I 2 have had this same identical problem and nothing in the world i have done to get it fix now i have a blown head gasket so i decided to replace the old worn out engine with a jdm replacement so when i have the engine out i am going to flush the entire clutch system out and replace with new parts

i even went as far as replacing the clutch booster which still didnt solve my problemi have bled, adjusted, and new clutch so i know how u feel i the guy that i bought it from only said he had a clutch problem.

there this one thing i havent tried that the guys from z1 told me to use super blue racing fluid cause it can stand up to 500 degrees and can with stand the heat.

try this tell me what happens

Spongerider

Changing the fuild will not help. Why would you need fuilds to with stand 500deg? Is you car stricly racing?

The clutch system is easy to figure out problems.

This is the hardware that wears out.
1) clutch master cylinder
2) slave cylinder
3) Clutch hose
4) clutch.

These are human error.
1) Bleeding procedure
2) clutch adjustment
3) improper installation.

It can not be the type of clutch fluid.

__________________
http://www.socalzcrew.com/gallery/ma...serialNumber=3

Zen31ZR

Might have a mild rear main seal leak. Should be somef residue around the bottom of the clutch bellhousing, though.
One thing to do might be to rebleed the clutch hydraulic system. If it has an air bubble, it will expand when exposed to engine heat for a long time and create pressure against the slave cylinder piston, forcing it out, effectively partially disengaging the clutch just as if you had actually pushed on the pedal slightly. Fluid expansion will also do this, particularly if DOT 3 and DOT 4 have been mixed together. In which case the system will need to be flushed thoroughly

__________________
1992 Yamaha FZR 1000. 145 Hp, all stock..

WILDFIREBLAZING

he suggested using a higher degree fluid because its when the fluid heats up and expand that causes my problem using a higher degree fluid would or shud have help to with stand the heat cause of its higher boiling point.

everything you have listed here i have done even the nissan dealer cant get it right had 5 certified mechnics who deals with this kind os stuff 4 a living tried n fail.