Datsun Roadster Forum-311s.org

Will,

I had an other car do what you described. The difference was that it was a cable clutch, so I KNEW that the clutch linkage was not part of the issue. The throw out bearing made noise for a couple of days then stopped. The clutch one day went from working fine to horrible. I could barely drive the car (lots of grinding...) I too was stumped on what happened.

Well when the mechanic took it down, he found that the throw out bearing had gone bad (the noise) and then seized (the noise stopping). The heat from the friction of the stopped bearing against the spinning diaphram spring resulted in a LOT of heat. This heat took the temper out of the spring and also ended up in the fingers of the spring being curled inward. The failure of the clutch to work was because the bearing was going through the pressure plate...

I drove it to the mechanic (SCCA race mechanic) who had the tranny out, clutch replaced and everything installed (pilot bearing, disc, pressure plate, throwout bearing, tranny, driveshaft, crossmember and even the clutch cable) and adjusted inside of 45 minutes. And he was complaining that it took so long because the exhaust pipe was in the way! He was the man on repairing that car!!

Anyway, I suspect this is what may have happened to your car...

Sid,
that does sound like what could have happened. I still havn't pulled the engine for a look and see. I am still hoping that the problem is external (as in the rubber hose flexing instead of moving the fork) but I will find out this weekend. The squeeking stared about a week after I installed everything. I thought it was clutch related, but everyone else who heard it thought it was a front weel bearing. Eventually it went away and I didnt think much more of it until this came up. If the pressure plate did die, I really hope it didn't do any damage to the flywheel. The friction surface is replaceable but aluminum can warp or crack do to heat.
Thanks,
Will

So I pulled the engine out this weekend to get to the bottom of this, but before extracting it, I tried the clutch and the master cylinder blew up (big mess all over the footwell). Obviously that was the big problem, however I am glad I checked the clutch it self because what I found was a little un nerving.

WARNING TO ALL WHO USE OR PLAN ON USING THE NISSAN ALLOY FLYWHEEL!!!! THE BOLTS THAT HOLD THE PRESSURE PLATE ON TEND TO WORK LOOSE! Mine were finger tight so I used lockwashers and locktite when I reinstalled it. A better way to deal with it is to use studs on the flywheel and locktite them into it with perminant locktite. (This wasn't thought of untill I had the engine back in the car.)

At any rate, the clutch disk was fine, the pressure plate was fine and the flywheel was fine. I guess I am glad that my master cylinder died before I went racing 2 weeks ago as I think the clutch would have come undone during the race or the drive home.

Will

Will,

It is a good thing you had the problems other wise it could have been a lot worse. Glad you caught it before it did some serious damage to your car and possibly yourself.

Steve