Back up on diagnosis

[blackwidow]

Ok I just wanted some quick back-up. I just bought a 85 300zx turbo. The guy told me that it won't shift while the car is running, and that if you do grind it into gear that it will konk out. Basically like the clutch will not disengage properly.

 

So first things in my head are slave/master cylinder, or clutch. So I get under the car and the slave cylinder seems to be moving the fork the proper distance, plus when I shine a flashlight in the hole where the fork is I can see it moving and depressing the pressure plate tongs/springs. There is also what looks to be fiberglass shavings in there( which I'm guessing is from a worn out clutch)

 

Now then I'm kinda just asking can a clutch wear out so bad that it won't disengage? Or is there anything that will cause this in the tranny?

 

So here is the rundown

 

Will shift when car is off.

Won't shift when car is running.

Hydraulic's all seem to be working fine.

Clutch fork moves freely and presses down on pressure plate.

 

 

I just don't want to buy clutch parts ahead of time only to not need them. Thanks

[BLOZ UP]

You should still be able to shift it while moving by pulling out of gear right when you let off and there's slack in the transmission, and then when the revs match the next gear and you are pushing the shifter slightly toward the next gear it should slip in when the speeds match up. If not the synchros are gone. Could also have a bent fork or two.

[Dan Juday]

My guess:

The friction material of the clutch disk is gone ("...There is also what looks to be fiberglass shavings in there...").

The metal part of the clutch disk (the part the friction material was attached to) has welded itself to the pressure plate or flywheel.

 

With the motor off shift it into 1st gear. Then start it and see if you can shift it as Bloz up described. If the tranny is good you should be able to do that.

[roger.svoboda]

you might as well bite the bullet and drop the tranny. Lots of things can go wrong in there that you can't see. You have to do it anyway so why waste time guessing or asking members for a clairvoyant seance reading. Even if it is a tranny problem you still have to take it out. four jack stands, tranny jack, and proper handtools you can have it out of there in under eight hours even for a first timer. search around plenty writeups on how to proceed. download the fsm from xenon full of useful information and it is free.

[Dan Juday]

...asking members for a clairvoyant seance reading. ...

 

Oooooo... I see a new clutch in your future. Oooooooo....

[blackwidow]

Very aware the tranny is gonna have to come out rodger, but I am not sure when I would be able to get to it and was hoping to have the parts ready when I took it out so I could get it on the lift and back down the same day. Was just looking for some back-up since it's been a while since I have had to diagnose anything really. I stoped being a mechanic years ago in search of cleaner/greener pastures if you will. At any rate thanks for the replys and suggestions.