clutch dead - 280SL 1971

[bourbeaue]

I have been the proud owner of a Euro 1971 280sl for 16 years. Lately, the clutch has been less and less effective. It now is almost impossible to shift gears, and very difficult to disengage from 1st. In fact, when I start it up in first with the clutch to the floor, it jolts forward as if the clutch pedal wasn't fully floored.

I have been reading plenty on rebuilding master cylinders, air bubbles and sticky clutches.  Not sure if any of this applies to me.

Can anyone suggest a course of action so I can get this fixed. I have found a list of parts online. Not sure what I need t order.

clutch pressure plate      W0133-1604906
clutch disk                      W0133-1610194
Master cylinder      W0133-1613351
Slave cylinder      W0133-1610036

Summers are really short in Montreal so I want to get this baby back on the road...

Thanks

Eric

[DaveB]

It certainly sounds like the clutch plate is not being fully separated from the flywheel. Maybe you could start by crawling under the car (chock wheels first) and having someone else operate the pedal to see if the slave cylinder is moving the clutch fork properly.

[Benz Dr.]

Sounds like you have some things to sort out. The slave cylinder is self adjusting but sometimes the master quits adding fluid into the system and you can slowly run out of pressure at the slave cylinder.
Watching what the slave does while you press on the pedal is a good idea. If it hardly moves this could be your problem. I would not try and rebuild a clutch master any more than I will consider doing that with a brake master. It's always new parts here. Too much risk for my liking.

[bourbeaue]

Assuming the slave (clutch fork) is not moving enough (how much is enough ??), how do I know if I should replace the master or the slave ?

Thanks for the advice.

Eric

[ja17]

Hello Eric,

If the problem is in the clutch hydraulics, the fluid res. will usually be low or empty.  Have you checked the fluid level?

[stickandrudderman]

Single handed method:
Clamp a hose clamp around the flexible hose at the slave cylinder. If you now have a hard pedal then you have proved your master cylinder is OK.
Next place a small block of wood in the clutch fork aperture to prevent the fork from moving and try the pedal again. If you still have a hard pedal then your slave cylinder is OK too.
There's nearly always evidence of fluid leakage with a failed slave cylinder.

[DaveB]

Hi Eric,
I get 25mm extension on the slave cylinder pin. I assume that's normal as my clutch seems to work ok.
If you're not getting that much, Stick's troubleshooting tips should isolate the problem to the master or slave cylinder (assuming the pedal set up is ok). If you are getting 25mm then I guess the problem could be broken springs in the pressure plate, though I wouldn't imagine that would be common with the diaphragm style 280sl plate.
Dave