clicking noise when clutch is in??

[fricker]

I just got my gearbox out of 4th gear ( 70E 911)thanks everyone!
and didall the shift bushing linkage and drove it. I hear a clicking sound only when I press down on the clutch while I'm driving. Any suggestions about what it could be and what can be done?
Could it be some part of the throwout assembly of the clutch?
Any ideas will help.
Thanks
Chris

[Grady Clay]

Chris,

This is more than likely the clutch release arm hitting the pressure plate when the pedal is fully depressed.

Take a little light on a wand and investigate the corner of the aluminum pressure plate housing for signs of contact. Look for aluminum transferred to the arm also.

You probable have the clutch adjusted for maximum release. That is good. It gets very expensive if the clutch doesn’t fully release. It eats syncros, sliding sleeves and gear dogs.

While the noise is obnoxious and you can feel it in the pedal, it really doesn’t do any immediate harm. However, it is an indication of wear. This can be caused by the socket in the arm and the ball on the pivot getting worn. That allows the arm to operate closer to the engine. This can also be from the release bearing or its attaching circlip wearing and having to move the arm closer to the engine to maintain adjustment. As the disc, pressure plate and flywheel friction surfaces wear, that makes this problem worse.

If the flywheel is worn or re-machined close to the spec limit and then the pivot is incorrectly shimmed this can also cause the contact.

First try and re-adjust the clutch. Of course make sure the retaining ring on the differential cover is in good condition and the clutch cable is like new. The critical issue is that the clutch fully releases when depressed.

You can Drimmell grind away about 20% of the thickness of the arm where it contacts the pressure plate. The pressure plate already has a chamfer on the corner. When installing a new clutch assembly you can have this chamfer enlarged for more clearance. Don’t use your engine as a lathe.


Here are some good links.
’70-’71 clutch
clutch cable for 70-71 901
and
'70-71 T.O. arm play?
and
http://forums.pelicanparts.com/porsche-911-technical-forum/166598-clutch-cable-70-71-901-a-post1520882.html#post1520882


The best solution is new components and undoing any previous kluge attempts at repair. The ’70-’71 clutch actuation was a Rube Goldberg at best. With all new components, the updates, and some careful workmanship it can work just fine.

Remember - - Don’t ever drive or shift a 911 with the clutch not releasing! Big $ will follow.

Best,
Grady