My clutch on my 86 na is not working properly. It will lose all pressure and have to be pulled up on to get to work again. If I pull the pedal back up and pump it a couple times then hold the pedal to the floor for a few seconds it regains most pressure for a few shifts. But if I start shifting quickly it loses enough pressure to the point where it sticks to the floor. I have rebuilt the master cylinder and bled the lines twice. Both times I bled the lines the fluid had black dust particles in it to the point that the fluid was basically black inside the master cylinder resevior. Where is this black dust coming from? And why does it come back after I flush the lines. The first time I flushed the lines the fluid stayed clean for like a week and then became dirty again.

 

don't rebuild the master cylinder. replace it. and replace the slave cylinder. and replace the damper with a 280ZX front brake hose. The rebuild kit sucks. You may get by with about 6 months after that, but it will fail again shortly.

http://zbum.nissanpower.com/280zx.brake.hose.mod.htm

 

is the damper used to keep too much pressure off of the slave cylinder rubber seal that is inside the cylinder housing?

 

there's a big debate on what the damper was really put there for.

a certified master nissan tech told me that it was because the clutches would sometimes have vibration problems and to prevent the pulsing sensation from reaching the driver, they placed a damper inline to smooth the feeling out.

 

cool, got the operator (slave) cylinder replaced, 280z brake line mod in place and functioning, and shifting has never been easier,
Thanks AZ-Zbum!

 

AZ-ZBUM you have some major tech advise that seems to work well.After reading some of ur remedies i decided to keep me 87 z31