Clutch pedal doesnt spring back, even seems to go in by itself
 

1983 240D My clutch pedal won't release sometimes when I shift. Sometimes it even seems to press itself in. Obviously this isn't safe in busy traffic or the highway. I tried making the two adjustments, one on the lobed screw on the clutch pedal and the other on the spring.
I have a strange guess--is this due to a sticking throw out bearing? The slave cylinder and the attached components were replaced brand new 2 years ago.

Check the clutch master cylinder. I just replaced mine at 275k and it was leaking like a sieve upon closer examination. Mine was exceptionally bad on cold mornings. By the way, are you having to add brake fluid to your reservoir??

clutch cylinder
 

Its fine. I also bled the slave cylinder. I also use a hand pump oiler to pump fluid into the cylinder through the bleed screw. I'm thinking this must be somewhere else.
Well anyway, I'm going to by a huge spring and jury rig it to yank the clutch pedal back no matter what until I figure this out. I tied a piece of rope to the pedal so in an emergency situation, I yank on the rope to bring the clutch pedal back. Obviously thats not Mercedes-type engineering!
This is really wierd. All of a sudden the clutch pedal will freezin place or even get retracted like an invisible foot is stepping on it.

Just because the slave cylinder was replaced two years ago doesn't mean the slave hasn't gone bad, just less likely it has. Did you simply look at the return spring or did you check it to see if it hasn't weakened/stretched? Is there a zerk at the clutch fork pivot point, possible that that lever may be binding/sticking. Also possible that the hydraulic line to the slave has begun to break down like an old rubber brake line (if the supply line is rubber), the interior could collapse which would restrict the return flow of hydraulic fluid. Also check the pedal pivot point up under the dash, make sure it is moving freely.

Check out all the easy to get to things before jumping to dropping the tranny. I've driven manny trannies for many, many years, and have never had a throw out bearing stick and cause what you describe.

My vote is for the hose
 

I've had two hydrolic hoses clog and cause problems. The rubber came out of the crimp. Had a local hydrolic shop make a hose for less than OEM.

The throw up, I mean throw out bearing wouldn't cause any clutch pedal problems, it would keep the clutch spinning.

I'm always suspisious of new parts cause of infant mortality, although two years would make that toddler mortality.

Put a rebuild kit in the master cylinder and that will fix your problem. You must also hone the bore of the master cylinder.
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