85 NA Original Clutch
 

I have 85 NA with 145K miles that has the original clutch. Now the clutch is stuck on the floor. There is still about an inch of movement when I press down on the clutch which still allows me to change gears, but not very well. I have heard that Z31 clutches are "bullet proof", but I guess after 34 years, the time has come. Thoughts?

Welcome to ZDriver! :006: Yeah, the Z31's OEM clutch is amazing but a lot of its potentially long life depends on having the same driver who always treats it the same smart way. I think my original '86NA clutch lasted well over 200K miles, but I never popped or dragged it, not ever. It loved me back. Nor did I ever let anyone else drive her. No point in that. A jerk (we all know a few) can do permanent damage in 10 seconds.

Anyway, your clutch is over now, sounds like. It is a former clutch. (You checked lines, no leaks, have tried (working with a good mechanic) to restore pressure to pedal, think clutch cylinder is OK, etc.) You can always blame the guy(s) who had her before you. Amazingly low miles for your Z, if true, motor hardly even broken in at 145K original! Congrats. But get a competent professional diagnosis and a 'replacement-required' verdict before you start hunting for a new clutch assembly.

You will find it hard to get the exact same clutch feel as your OEM from your replacement clutch. The OEM (I remember well) just seemed to be a perfect match for the motor and torque. Viva amazing Nissan designers! And I know nothing about "rebuilding" a clutch, way above my pay-grade. Others have done it, however. So talk to whoever claims to be the clutch "expert" at your parts store and try to describe what you need in a replacement. I installed one that was so hard I replaced it after 50 miles. Truck city, much too hard. I could not match OEM exactly but at least found one that was tolerable. Good luck with this. Don't be too shy to switch out a bad new replacement (wrong feel for you). Hey, it's only money! Get it done right, buddy.

So the Clutch Master Cylinder was "bone dry" (but I couldn't find a leak anywhere???), I topped it off with Dot 3 Brake Fluid. Once I started to pump the clutch the pressure restored to the pedal and shifting gears was the best its been in years. However, after driving awhile without changing gears, the pedal would lose its pressure. When at a stop of I would pump the clutch pedal multiple times and the pressure would restore. I guess its time to replace the Master Cylinder. Any recommendations for a good Z mechanic in Maryland?? I live in the Annapolis area...

Yes it does sound like the master cylinder should be replaced. I’m not sure about a mechanic in Maryland, but I know you can buy one off rock auto for about $12 plus shipping and watch a YouTube video on how to install it yourself. On these it’s just a couple of bolts, BUT make sure you bleed it right and get the air out of it after you swap it in. Best of luck, and if this doesn’t fix your problem you will have to put in a new clutch kit and might as well do all the seals and resurface the flywheel as well. Flywheel can be done at your local machine shop for $25-$50. If you take it to a mechanic for a clutch your looking at a pretty high price, at least around where I live in Georgia.

Did you bleed it? Might want to try that before you replace it.

So for me these symptoms were both the slave cylinder and the master cylinder. The slave cylinder was leaking and the master was underperforming. Took a while to get pressure back after refilling for me.

I replaced both. Fairly easy job except for the bleeding. Mine is a Z32, but should be similar in both symptoms and replacement.

It sounds to me like maybe yours is just the slave cylinder leaking. I might still replace them both as the parts are cheap and the effort isn't much more to do both at the same time.

Its very likely that the clutch is seized to the flywheel , if it sat for years. But yeah fix the hydrolics first