The strangest little thing...

Efrain68912 · 02-28-2002, 08:43 PM

My 912's clutch was adjusted with about half an inch of free play before it disengages. I've noticed lately that when the pedal is within that half inch of free play, it shudders a lot. The clutch action isn't any different; the clutch, pressure plate, and clutch cable are less than 3000 miles old. The trans was rebuilt at that time and the flywheel resurfaced. It is leaking a bit from the flywheel seal (because I was in a hurry to put the car back together and didn't take the extra time to replace it, like any rationally thinking person would have.

Any ideas? Thanks.

912 Owners Meeting March 9th at Pelican Parts!
(I'll bring some racing footage from Phoenix).

Jeff Trask · 02-28-2002, 09:18 PM

Oil on the clutch disc?

josh912 · 02-28-2002, 10:15 PM

Your flywheel's on good, right?

My real seal leaked after the gland nut failed. Go figure. Otherwise I'm with Jeff on the oil. It can cause havoc, and it gets on everything humanly possible. Does the clutch slip at all? The oil normaly will cause it to slip. I just hope it ain't anything serious. I'm getting chills thinking about flywheels right now.

Alan.UK · 02-28-2002, 10:41 PM

Will worn gear box mounts make the car shudder when the clutch is disengaged?
Just a thought.

Alan.UK

Plato · 02-28-2002, 11:48 PM

How does one go about cleaning up a mess like that? Any one ever done it?

josh912 · 03-01-2002, 10:21 AM

Quote:

Originally posted by Plato
How does one go about cleaning up a mess like that? Any one ever done it?

Carb cleaner works great.

Seriously, if the rear seal is leaking the only way to fix it is to take the engine out. If it isn't leaking real bad then its not worth it. Plus, there is always the chance that the new seal will leak too. I've gone through 3, yes 3, in 100 miles!!!!!! First one leaked, second one the spring broke before the car reached the driveway, and third one failed with the gland nut. Shiesh.

Another option to clean the clutch is to do a 6K burn out!

Efrain68912 · 03-02-2002, 07:30 AM

There is no clutch slip; oil on the clutch disc was my initial thought as well. The car doesn't shudder unless I release the clutch at too low an rpm - the gearbox mounts are 3 years old, but they are the rubber ones. Wish I had solid.

Oh well. At least I can drop the engine in about an hour, by myself.

Green 912 · 12:36 PM

from your discreption an oil wet clutch disk would be the first thing I looked at. The clutch disk will feel like it is grabbing the flywheel and twiching at low RPMs if it has any oil on it. At low speeds a slightly oil contaminated clucth will feel "grabby". You don't tend to feel it at high rpms as there is enough energy to pop the clutch disk well away from the flywheel as the pressure plate pulls away. You could also have something binding the clutch disc splines that is keeping it pressed slightly against the flywheel. Is the shudder only felt on release? Are all the motor and trans mounting bolts tight? Are the rubber motor blocks good?

BTW. It is easy to hard mount the trany but you should also hard mount the motor if it isn't already otherwise you get bad twist energy transmitted into the cases. You can make a nice trany hard mount in about an hour from an old cheap 911 mount with only a little welding and some metal. Motor mounts can be easly made from cheap stuff too. Nice tight shifts and motor response but LOT of noise in the drivers compartment.

When a clutch disk absorbs oil it is trash in my book. You can only clean the surface and when you heat it up the imbeded oil comes out. I even spray the flywheel and the pressure plate with brake-kleen prior to asembly and never touch the clutch disk with greasy fingers. A bad gland nut bearing can cause a seal failure.