Clutch problem 1973 350SL

[Shiraz1965]

Newbie here. Recently purchased a 1973 350SL with 4-speed manual transmission.
As I was driving today, my clutch pedal wouldn't come back up. Pulling up on the pedal springs it back up in position and doesn't drop to the floor. If I press it down again, it stays depressed and clutch does not engage.
Haven't had a chance to investigate too much but where should I start looking?

Thanks for your help

[Sugar Bear]

Check the fluid in the brake master cylinder. Look at it very closely as there is a hard to see divider/wall that makes it difficult to see the rear section fluid level.

Look for leaks above the clutch pedal (clutch master cylinder) and on the side of the transmission (clutch slave cylinder).

It could also be a worn thru clutch fork at the pivot ball.

My guess is it is time for a new clutch slave and clutch master cylinder, the cloth hose between the brake master cylinder and the clutch master cylinder and the line between the clutch master and the slave cylinder. This would be an overhaul of the hydraulic clutch application system; but, look for leaks first and a worn clutch fork.

Good luck!!!

[Shiraz1965]

Not seeing any leaks anywhere and the failure seems more mechanical than hydrolic. Again, once the pedal is depressed and stuck to the floor, I just need to give it a small tug and it springs back to the upward position.

[Frank Reiner]

Originally Posted by Shiraz1965

Not seeing any leaks anywhere and the failure seems more mechanical than hydrolic. Again, once the pedal is depressed and stuck to the floor, I just need to give it a small tug and it springs back to the upward position.

Does the clutch disengage when the pedal is down, and engage when the pedal is up?

[Shiraz1965]

Not seeing any leaks anywhere and the failure seems more mechanical than hydrolic. Again, once the pedal is depressed and stuck to the floor, I just need to give it a small tug and it springs back to the upward position.

[Shiraz1965]

No, the pedal has no impact on the clutch engaging or disengaging. The car is always in gear.

[Sugar Bear]

Try to have someone watch the fork/slave cylinder junction while moving the clutch pedal to see if the slave moves the fork.

[Frank Reiner]

Originally Posted by Shiraz1965

Not seeing any leaks anywhere and the failure seems more mechanical than hydrolic. Again, once the pedal is depressed and stuck to the floor, I just need to give it a small tug and it springs back to the upward position.

Originally Posted by Frank Reiner

Does the clutch disengage when the pedal is down, and engage when the pedal is up?

Originally Posted by Shiraz1965

No, the pedal has no impact on the clutch engaging or disengaging. The car is always in gear.

Originally Posted by Sugar Bear

Try to have someone watch the fork/slave cylinder junction while moving the clutch pedal to see if the slave moves the fork.

SB: The slave cylinder push rod and the release lever are entirely within the bell housing, and are not visible.

S1965: Suggest as a first step that the cover(s) under the steering column be removed so that the motion of the clutch pedal & the clutch master cylinder push rod can be confirmed. Steps after that point involve the motion of the hydraulics.

[Shiraz1965]

Think I found the problem. Looks like I'm looking at a bad slave cylinder. Hopefully not too bad a job. Might need to loose so weight to make things easier.

[fonzi]

I believe I was successful in using a 240d slave cylinder bc the one for a 350sl is so expensive or NLA or something. The original pushrod is required though (I believe).

Somewhere on Benzworld I documented replacing the slave cylinder on my 1973 350slc. https://www.benzworld.org/threads/1973-350slc-4-speed-11-2019-purchase.3040336/

[fonzi]

Originally Posted by krishay.baxter

It could be a worn thru clutch fork at the pivot ball.

Or a very old thread. :-)