Clutch Master/Slave Replacement Procedure - PeachParts Mercedes-Benz Forum

mjquillici · #1 02-10-2009, 02:15 PM

Hello,

Could somebody possibly walk me through (or point me the thread) for replacing the clutch master and slave cylinder on a 1982 240D. I looked in the DIY section, but couldn't find what I was looking for.

Thanks,
Mike

winmutt · #2 02-10-2009, 03:27 PM

Master is done one of two ways.

If you have small fingers and dont mind being upside down for extended periods of time you can replace it in place. Otherwise I recommend removing the pedal assembly.

Slave is straight forward but make sure you have some decent crows feet to get the hard line off with.

Bleeding is done by hooking the slave valve to the pass front brake and pumping the air out.

rs899 · #3 02-10-2009, 03:58 PM

You don't have to be upside down to replace the M/C. You can kneel outside the car and squeeze in and tilt your head. Not easy. Removing the pedal set is no improvement- you still need to get to those 4 bolts on the firewall- that seems like added work and pain.

Be careful on the hydraulic line on the slave. I chose to remove the slave with the line intact (disconnect just in front of the master cylinder) because there is a good union there that is harder to screw up. If you round off that hydraulic fitting on the slave it's gonna be trouble.

Rick

Stevo · #4 02-10-2009, 04:17 PM

Yet another way, I remove the seat which gives an old guy like me plenty of "twisting room" to get under there

. I have left the old push rod, which is the tough part to replace, I couldn't see any ware so I took the short cut.

winmutt · #5 02-10-2009, 04:29 PM

On a turbo engine its all but impossible to get the master off without loosening the pedals a bit. The pushrod comes off easy but dont forget to re adjust it at the top.

yellowbenz · #6 02-10-2009, 05:11 PM

I vote for removing the seat. Have done it with and without removing the seat and it was much easier on my neck and back with the seat removed. This is a really painful job. I've done it on a 240D and 190D. I would recommend removing the hard line from the master before loosening the two bolts holding it to the pedal assembly. Otherwise you'll likely bend the hell out of the hard line trying to loosen it from the master cylinder. I need to replace the slave on my 240D and I'm really dreading it. I think there is a pretty good writeup in the Haynes for this procedure.

fruitcakesa · #7 02-10-2009, 05:29 PM

I just did my clutch MC and taking out the seat helps a lot.

Stevo · #8 02-10-2009, 06:03 PM

Quote:

Originally Posted by yellowbenz

I vote for removing the seat. Have done it with and without removing the seat and it was much easier on my neck and back with the seat removed. This is a really painful job. I've done it on a 240D and 190D. I would recommend removing the hard line from the master before loosening the two bolts holding it to the pedal assembly. Otherwise you'll likely bend the hell out of the hard line trying to loosen it from the master cylinder. I need to replace the slave on my 240D and I'm really dreading it. I think there is a pretty good writeup in the Haynes for this procedure.

The slave will be a piece of cake, plenty of room.

Sometimes it easier to start the hard line threads then the two 13mm bolts

Edmund · #9 02-22-2009, 11:05 AM

Im busy replacing the rubbers on the mc on my 124 230E. Removim the seat and pedal assy worked out best for me. The problem is that I cant refit the suppy hose. Does anyone know how to do this?

chetwesley · #10 05-09-2009, 07:06 PM

I am planning to do this tomorrow and just went out and took a look - seems straight forward - why do people say it is painful or difficult? something I'm not getting about it?

Seems like you just remove the hard line from the bottom of the MC, then the two bolts, and squeeze the boot to get the push rod off with it.

I was thinking of just reusing the push rod and leaving it up there - is there any danger in that?

Anything else I should know?

yellowbenz · #11 05-09-2009, 11:09 PM

It is straightforward if you follow the steps, have hands the size of a 10 year old, are very thin and do daily yoga

I didn't reuse the push rod, but that might not be a bad idea. Mine just fell apart after it came out of the assembly and I assumed that was because of the internal seal failure, but perhaps it is designed this way. You are going to find out I suppose so a report back here would be helpful for others who go down this path.

chetwesley · #12 05-10-2009, 12:36 AM

Do you mean that the push rod came out of the MC, or do you mean that the top part where it fastens to the pedal somehow broke? I don't understand how the seal failing would cause the rod to fall apart, but it does come out of the boot and the MC pretty easily, as it isn't really held in by anything other than the rubber boot.

rs899 · #13 05-10-2009, 06:21 AM

Correct- there's nothing holding the rod to the cylinder, so removing the M/C and leaving the rod attached at the top may be useful. When you get the cyl out assess the rod and see if you can reuse it. That's the least accessable part of the M/C.

Rick

charmalu · #14 05-10-2009, 12:09 PM

Quote:

Originally Posted by Edmund

Im busy replacing the rubbers on the mc on my 124 230E. Removim the seat and pedal assy worked out best for me. The problem is that I cant refit the suppy hose. Does anyone know how to do this?

That supply hose is a pita to attache, it is only like 14 inches long. I had a 2 ft piece I pushed through the groment, and then fastened to the MC. Had my assistant pull the hose back and I positioned the mc and bolted it down.
then cut to length the hose, and pushed it on the brake reservor.

Charlie

chetwesley · #15 05-10-2009, 04:02 PM

quick question - got the old MC out - ok so far (the top of the MC popped open when I took it out - spring flung to the top parts off, which may explain my problems... we'll see)

Anyway, the plastic hose fitting/barb that connects the supply line to the MC - it is stuck in the MC. Any advice on getting it out? I don't know if it is just inserted tightly in there or if there is something else I need to know about it - I just don't want to break it trying to get it out to put into the new MC.

Thanks