clutch bleeding

[n/a]

When doing a search for the clutch bleed procedure, I only found a very brief description of the technique and a reference to a more detailed description which I was not able to find.

Can anyone direct me to the complete detailed procedure on bleeding the clutch.

Thanks,
Brian

Brian

[ja17]

Hello Brian,
The clutch hydraulic system can be bled by opening a front brake bleeder and the bleeder on the slave cylinder. Connect a hose between the two and slowly push the brake pedal a couple of times. Close both bleeders off and you should be ready to go.

I have also used a pump oiler with brake fluid in it and connected it to the bleeder on the slave cylinder with a rubber tube and forced the air out this way without disturbing the brakes.

Another method which works some times; try pumping the pedal about a hundred times. Be sure to push the pedal all the way to the floor. Gradually the pedal will begin to work. Allow some time to rest from time to time so the air will rise in the system.  Soon afterward all the air will be forced out and you will have a full pedal.

Joe Alexander
Blacklick, Ohio

[Naj ✝︎]

Another way that works for me:
Fill the resevoir 2/3 to 3/4 full.Leave cap off.
Get under the car and work the piston/rod back into the cylinder.
You will hear the air bubbling out of the resevoir and the piston will come out again sucking fluid with it. A few strokes and no more bubbling.
Now try the pedal. Top up resevoir and fit cap.
naj

65 230SL
68 280SL

[Ben]

Just digging up this old topic for some advice. My clutch pedal had started to feel quite weak and occasionally stuck half way, so thinking it needed to be bled I set myself up to bleed it at the master cylinder, since it was parked on my driveway and I had no jack or stands.

Anyway I was surprised that NO fluid came out at the pedal nipple. I had a tube on the nipple into a full jar and pumping the pedal did absolutely nothing !

Anyway my pedal was no worse, so I had obviously got even more air into the system and I decided to go get my jack and stands and witht the aid of a helper I connected the slave nipple to the left front caliper and proceeded as normal. I got a fairly good pedal and was happy so I cleared up and was about to go for a drive when I pressed the clutch and it hit the floor...........and stayed there !

So what has gone wrong or what have I done wrong.I've ordered a master cylinder repair kit anyway but I wondered if I may have "flipped" the seals somewhere, as you can do with a brake master cylinder if you are too fast pumping ? I was extremely slow pushing the clutch pedal down as I am reluctant to have to remove the master cylinder 'cos it looks original and the pipes look like they'll never come off as they are quite rusty looking at their joints.

Should I try bleeding again or has anyone any tips or thoughts ?

Regards,
Ben in Ireland.
'64 230SL 4sp.

[ja17]

Hello Ben,
Take a look at the slave cylinder on the transmission. Make sure the slave cylinder is not extended, if so the problem may be in the clutch assembly. Otherwise it sounds like you may have a damaged seal (not usually prone to sudden failure) or a completely restricted clutch hose.

Joe

Joe Alexander
Blacklick, Ohio

[Vince Canepa]

When my clutch pedal was hanging up it was the master cylinder causing the problem.  A pressure bleeder makes things fairly easy, both for bleeding the clutch and flushing/bleeding the brake system.  I bled the clutch from the bottom up with my EZ Bleed.  There are several pressure bleeders on the market now that are fairly cheap.

Vince Canepa
1967 250SL
113.043-10-001543
568H Signal Red
116 Caviar MB-Tex

[Ben]

Okay guys I got it solved !

I dunno why it wouldn't bleed from the caliper but I hooked up the master to the other caliper and pumped for a bit with not much luck!

I wa about to give up when I decided to do Naj's trick of moving the slave rod back and forth and I instantly heard the glorious sound of gurgling bubbles. Kept at it for few minutes and now I have a perfect pedal !

Still gonna install the master rebuild kit though !

Thanks Joe and Vince !

Regards,
Ben in Ireland.
'64 230SL 4sp.

[n/a]

Hello there! Newbie here, with a related problem. This seems to be a good source of knowledge so I give it a try!
My sister's 64 230 SL was suffering from decreasing response to the clutch for a period of a couple of years. Had to pump the clutch pedal several times to get the clutch to release and to get the gear shift to work properly. A few weeks ago the pedal just got stuck down in the floor, but it could be withdrawn by hand.
So I got under the car and undid the bolts of the clutch slave cylinder to check it out.
The rubber boot had a few holes in it where the fluid came out, definately the reason of the leak.
So do any of you guys know if this boot is interchangeable with other MB slaves? My guess is that MB used this same slave cylinder for other models as well. I'd appreciate it if it's possible to get one that is OG MB. Does anyone know the part number for this item?
brgds
André

[Benz Dr.]

What often happens is the bleed screws will be plugged with dirt or the hole at the bottom under the screw will be plugged.
I'm not big on rebuld kits for things like master cylinders. There can be wear inside the cylinder and it can fail when you really need it most. Due to liability, I replace ALL master cylinders with new units or have the customer sign a waiver.

Dan Caron's
 SL Barn
benzbarn@ebtech.net
 slbarn.mbz.org
  1 877 661 6061

[Naj ✝︎]

Hello Andre
 

quote:The rubber boot had a few holes in it where the fluid came out, definately the reason of the leak

If you found brake fluid in the rubber boot, its probably leaked past a worn piston seal.

The repair kit for a 230 SL clutch slave cylinder is Part # 000 586 0929.

naj

p.s:You may want to take the 'Good Doc's' advice and do the master cyl at the same time...

65 230SL
68 280SL