'94 GLX - Clutch pedal goes all the way to the floor!

[fred_s]

This came on all of a sudden. I've worn out many clutches before, and I don't believe that this is a case of a worn clutch (although it may indeed be worn). One day, I get in the car to drive & I press the clutch pedal and it goes all the way to the floor, with very little resistance. If I were to compare - it felt the same when bleeding brakes, when the valve gets released and the pedal sinks to the floor. Interestingly, if I pump the pedal a few dozen times, the pressure returns, and eventually I can use the clutch again, and it performs as normal. After the car has sat parked for an extended amount of time (10-12 hrs), then I discover it has lost all pressure again. In contrast, after only an hour or two of being parked, I can return to the car and there's no apparent loss of pressure.

I know the clutch is hydraulically manipulated, but I can find no leak of fluid anywhere (it might help if I knew of some place to look other than the ground beneath the car). Besides, I've been driving the car like this now for over a week (having to pump up the clutch before taking off), so I would think that if the problem were due to loss of fluid - as in, a leak - then I would be out of fluid at this point. Further, I don't see how the pressure could build back up if I have a leak of some sort (just my best guess). I'm wondering if what I'm experiencing is possibly the slave cylinder going bad?

Any help would be appreciated, as usual. Thanks!

[boschmann]

It could be either going bad. I assume there is enough fluid in the reservoir. Try looking where the push rod goes into the master to see if there is moisture there. Similarly the push rod of the slave should be inspected. I have seen bad fluid cause similar problems, has it ever been changed or bled.

[fred_s]

Thanks Boschman, for the reply. I'm not sure about when/if it has ever been changed. I bought the car used about a year ago.
I'll take a closer look at the slave cynl, to see what I can see.
I've called around & found replacement master & slave cylinders for a reasonable price, and I was told by my mechanic that "if you're going to replace one, ya might as well replace 'em both". Is this pure 'mechanic speak' (no offense to any mechanics out there), or is there truth to his advice?
Also, should I choose to take on this task myself, how difficult is it to perform with a basic set of tools? Would I be better off letting a pro handle it?

TIA

[boschmann]

There is truth in that as far as if one dies from corrosion the other is probably corroded also, & has the potential to go out soon. When you're getting paid to repair it you tend to make sure it won't go out in a similar fashion anytime soon, as you get unhappy customers. It doesn't require special tools although the work space is fairly difficult.