funny clutch pedal travel

[Bukowski]

'87 944 na

with engine off, when I press the clutch down its OK. when i release it, it goes ok up to a point, but feels caught on something, then further release is OK.

i am investigating this, but is there a cable that needs periodic adjustment that bears upon these symptoms?

[argiopeweb]

From "http://www.pelicanparts.com/techarticles/944_clutchcyl/944_clutchcyl.htm", " The Porsche 944 uses a hydraulic clutch engagement system - there are no cables involved with the actuation of the clutch."

Is this a new issue? Do you have this issue while the car is running?

[Bukowski]

Originally Posted by argiopeweb

From "http://www.pelicanparts.com/techarticles/944_clutchcyl/944_clutchcyl.htm", " The Porsche 944 uses a hydraulic clutch engagement system - there are no cables involved with the actuation of the clutch."

yes, that confirms what I gathered... actually I just read that today...

Originally Posted by argiopeweb

Is this a new issue? Do you have this issue while the car is running?

yes this is new. it does happen when the car is running BUT I am investigating this starting last night...

so I do have to study things a bit, but are there nuts or something to adjust the pedal? the brake pedal has that, so I thought the clutch (and accelerator ) would...

[argiopeweb]

The actual clutch travel is automatic due to the hydraulics, but you can adjust the pedal play via a nut near the top of the clutch pedal. It's a general pain to get to unless you're a gymnast. I highly recommend having the seat all the way back and the e-brake in the full down position. Clark's garage can help with the rest.

[Bukowski]

OK, thanks - I thought I saw some adjustable hardware in one of those photos. I'll try it out.

EDIT: ... this appears to be a very straightforward adjustment in the Haynes manual as well.

[Bukowski]

OK, so I took a look.

the boot on the cylinder is split. I do not see fluid leaking. brake fluid is at normal level.

the pedal travel can sometimes stick halfway and has to be pulled up with my toe.

how likely does this mean a clutch cylinder replacement? it is very old.

I have to go read about signs of a bad clutch cylinder.

[mikepellegrini]

It could also be the clutch slave cylinder - which is a whole lot easier to replace.

[Ederd]

Best bet is to just go ahead and replace master and clutch slave. flush the lines with denatured alcohol and put in new fluid. I had no documentation when these were replaced or if ever by Po's, so it made me feel better and more confident to just go ahead and replace both at the same time. If any issues come up in the next year or so it will be a lot easier to diagnose the problem. Only issue i had was making a gasket for the master cylinder. I just did some research and instead of the cork gasket, some have made one out of corrugated card board( i used the pelicanparts box that my parts came in as a gasket). so far so good and no leaks and have no issued with pedal travel. Oh yea its sooooooo much easier to take out the drivers seat

[Gawernator]

Don't forget to change the hoses if you do change the master and slave.

[Bukowski]

UPDATE 1:

after some reading ( including a superb video by Juergen (Dr944S2) on clutch hydraulics - https://www.youtube.com/watch?v=cM3w-JBMbdE ), it sounds like there are two camps: one says replace the CMC+CSC and all that, and another focuses on the two springs, in particular this thread on a 997 - is a 997 any source of guidance here?:

http://forums.rennlist.com/rennforums/997-forum/534098-does-your-clutch-pedal-pop-during-return-travel-read-on.html

one spring is in the PP catalog as 321-721-191-OEM , the other is 477 712 353 A is NLA.

what is the larger spring supposed to look like when flexing? mine seems like it is bending in the middle. there appears to be a plastic part that could be worn out - it is hard to see clearly.

can't see the top spring at all.

UPDATE 2:

also found this guy on Clark's Garage forum with precisely the same trouble, but with a new CMC and CSC:

http://www.clarks-garage.com/phpBB2/viewtopic.php?t=2844&sid=306db7295eabe9e13f17dc8e59f6b89c

that thread ends without any update or resolution, HOWEVER, user grapedog later posted this:

http://www.clarks-garage.com/phpBB2/viewtopic.php?p=47352&highlight=&sid=8a325b1363d923a38797d66bd0b04743#47352

... in which it is claimed that repeatedly bleeding the system solved the problem - nothing to do with the springs...

It is still unclear to me what the springs or plastic bumper piece on the lower spring are supposed to look like, feel like, operate like, or how they change as a consequence of the pressure from the hydraulics.

i.e. if the springs are bad but a good CMC+CSC cover it up, could this damage the cylinder?

UPDATE 3:

when car is running:
clutch pedal depresses OK - gear shifts OK.
clutch pedal returns however it feels like there is a hump it has to go past about halfway on the return.
still cannot see any brake fluid dripping or change in brake fluid level.

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original post:

OK, is this normal? - what is the motion supposed to be like - is there a missing pin - anything else