62 220seb clutch pedal has a slow return

[Robert O'Brien]

After changing the slave cylinder, my clutch pedal now returns slowly.  Comes off the floor slow then pops up from the spring pressure.  The fluid was renewed when the slave went in and bled of air.   Could this be the Master Cylinder that is creating this slow return? The pressure holds when pedal is depressed and in gear.  Before, slave would leak and you had to quickly get it out of gear.

[GGR]

I would think the hose between the master and slave cylinders went bad. Like for the brakes, they decompose from the inside and let the fluid go one way thanks to pressure but then prevent it from going the other way. But I would imagine the fault would have been there also with the old slave cylinder, the the problem may be else where.

[wbain]

The hose is twisted. Loosen the hose at the chassis and then tighten the hose at the slave cyl. Tighten the hose at the chassis next, using two flare nit wrenches.

[ejboyd5]

The hose is twisted. Loosen the hose at the chassis and then tighten the hose at the slave cyl. Tighten the hose at the chassis next, using two flare nit wrenches.

This appears to be a spot-on solution based on actual experience.  I hope "obsdiner" confirms when he completes the repair.

[Robert O'Brien]

Removed Slave and checked line.  No twist, just an easy curve up to a junction where it transitions to the hard line that goes to the master cylinder of the clutch.  Still slow after re bleeding and can hear a sucking sound from the master when pedal comes up.  I feels like suction is keeping it from an easy release. 
Thanks for the help,
Bob

[Jack Jones]

I had an issue with my 5 speed 107 chassis where the clutch pedal would go to the floor on its own. After inspecting the hydraulic system I found a great deal of sludge in the master, hose and slave cylinder. Since I had already purchased a complete set of original Mercedes parts I install them and have never looked back. The pedal has never been so smooth and easy to depress. I believe you have the same if not a similar sludge present and bleeding the system is not removing it. The low cost of replacing the hydraulic fluid ever couple of years would have prevented this.

[wbain]

Then he should remove the slave cyl, take it apart, hone it and install a new seal and boot.

[Jack Jones]

The slave is new and not likely the issue unless it is a cheap Chinese part  . If there is a sludge buildup in the master and/or feed or discharge lines, this could be the problem. My car was 27 years old when the problem happened and based on the buildup in the entire clutch hydraulic system, I believe it never had the fluid replaced. 

[Robert O'Brien]

I purchased the slave from Autohauz. Pricey so I think it's German.  Did not have this pedal issue before the change. Only lose of hydrolic at the slave.  Pedal now holds pressure but slow to return.  Looks like I need to remove all the parts ie: Master, lines and slave to clear out this problem.  What is a symptom of a bad Master clutch cylinder? If after I do all this and still have pedal return problems is the Master the problem?
Thanks, Bob

[ja17]

Replace the rubber hose. It should be renewed as they become restricted inside as do the brake hoses.

[jpressick]

Need some help on this one.  The clutch master cylinder,  the slave cylinder plus the flexible hose are all new.  The problem comes when I depress the clutch pedal the clutch master cylinder slips downward  from the sleeve.  When this happens the clutch pedal goes to the floor.   Any suggestions would really be appreciated.  Help  Jim

[Jack Jones]

Jim,

There should be a lock ring that prevents the clutch master from moving once installed in the sleeve.

[ja17]

Check the free-play at the slave it should be  1/16" to 1/8". If you have too much that is the problem.