HELP! Clutch Problem

fc3286 · 10-22-2002, 04:09 AM

Got into my car this morning and depressed the clutch pedal-it went straight to the floorboard and stayed. I could pull the pedal back but there was no spring to it. Any Ideas.

Thanks.

Lawrence Coppari · 10-22-2002, 04:50 AM

More than likely it has gotten air in it or your master or slave cylinder has gone bye, bye.

You could have developed a leak in either so the fluid level lowered picking up air.

fc3286 · 10-22-2002, 04:56 AM

Had a new master cylinder installed a couple of months ago. I think they are connected-my brake fluid has needed refilling. Maybe 1/3 cup every 3-4 weeks. Thanks again.

mike944 · 10-22-2002, 06:16 AM

Probably about a 95% chance it is a bad slave cylinder. They should always be replaced in pairs. When you replace only one, usually the other one goes within a month or two.

Mike

turbohead7 · 01:37 PM

Yo fc3286, I know exactly whats wrong with yor pedal, Lawrence Coppari is right on the money. You do have air in the system. Get a light and crawl under the driver side dash. Look up at where the clutch master cylinder pushrod comes through the firewall, there is a black boot on it. In the bottom of the boot is a weep hole designed to let brake fluid escape the boot to indicate a leak (like an H20 pump). Usually they are soaked, and the fluid leaks down behind the carpet, sometimes on your shoe. The clutch circuit shares the brake master fluid supply via a blue fabric/rubber hose. It can be seen coming off the driver side of the resevoir. This will explain your fluid loss. A leaking clutch slave will usually leave a stain on the ground, and can easily be seen by peeking under the car at the driver side of the clutch bellhousing. Wetness will be apparent if it is leaking. Replacing the clutch master and clutch slave cylinder as a set is up to you, you will eventually have to do both. Another critical item to check is the line in between the master and slave, it has a rubber section in it which is prone to failure. I've replaced many a master only to hook up my bleeder and find fluid gushing out a split in this line, which actually closes when the pressure is released! Bottomline: go over the system thoroughly before proceeding. Also, if you plan to fix it yourself, the blue hose I spoke of earlier is usually very brittle and crumbles up when touched, it is special hose which can only be got at a dealer, in a three foot section usually! A pressure bleeder is almost always necessary to get all the air out, actuate the pedal frequently with a hose/pickup bottle at the other end (slave). !IMPORTANT!: There is a free play adjustment on the master pushrod, it must be 1/2"-3/4" at the pedal, don't assume it was correct in the first place! Too much freeplay won't disengage the clutch fully, causing premature failure of the disc. Too little or no freeplay will over-extend the throwout bearing, slowly pulling it apart, untill one day---bang-stop. I advise all 924/944/951/968 owners to do these checks, I'am sure many of you have leaking masters and don't even know. Good luck people.

AFJuvat · 10-23-2002, 07:21 PM

Yes they should be replaced in pairs.

Also, one thing to keep in mind is that many of these parts are NOS - New old stock. Some of these parts have been sitting on the shelf for many years. As a result the seals can fail quickly.

If you want piece of mind, you can always buy a new cylinder and then rebuild it with new seals.

1/2 - 3/4" free play on the clutch? Was there a supercession in a TSB since 1997? The specs we have show free play not to exceed 5mm.

Welcome to the group.

AFJuvat

turbohead7 · 10-26-2002, 01:36 PM

I may have over exaggerated the freeplay spec. Sometimes I loose my train of thought on a long post, you know? The 5mm spec. is more accurate equating to approximately 1/4", I never was that good at math. I've done so many of these adjustments that I know how the pedal is supposed to "feel", follow? 5mm can be tuff for a less expierienced person to guage, so I figured at time of the reply that 1/2" would be remembered and executed more easily. Porsche doesn't list a pedal freeplay spec. because it is a hydraulic system. They actually want you to measure the pushrod length, which would have been more difficult to explain, and even more difficult for the questioner to execute. Does your 5mm spec refer to the pedal, or the gap between the pushrod and master cylinder piston? The first few times I installed a master in a 944 I did the pushrod measurement which on average gave the pedal a freeplay amount of 1/2". I stand corrected Good Sir.