What the heck is up with bleeding the clutch?!

Well I have searched here, and my skills are poor as I've found a bit but nothing conclusive!
Apparently a common problem, new cutch slave cylinder and flip me with a flipping stick, this thing doesn't want to bleed!!

Gravity bleed - fail.
Vacuum bleed (repeatedly) - fail.
Pressure bleed (thank you Gunsons..) - fail.
Wedge clutch pedal down and walk away for a day - fail.

Remove slave cylinder again (leaving it plumbed in), try to unwind the stupid plastic loop (what's that even for?), wedge the cylinder between the frame rail and engine mount at precisely the right angle to get the bleed nipple at the absolute apogee and pressure bleed again four or five times. Partial success!!!!!

Pedal doesn't do much for first half of travel, but seems to firm up for the second half. Of course I can't actually check the biting point as the engine is missing it's head right now.

Come on then now people, what's the trick with this daft thing??!!

Try taking out the slave & push the piston all the way back. Hold piston back and bleed.
Nipple at top

Yes it can be a pain, when I replace my slave and master, when my foot hit the floor, I took the mastrer outstripped it and found the spring had broken up, so I got a new on plus a slave installed them and like you no joy as it turned ou I had a split in the pipe on the plastic yub at the bottom so I replaceed the pipwork as well, as my new pipe was a flexible I was able to sit in the driver seat pump the peddle myself while bleeding the slave at the door frame,

First of all what did you replace as the clutch needed beeding?

sierrafery said:

First of all what did you replace as the clutch needed beeding?

Click to expand...

Well that is a long story.... in a nutshell it's not my vehicle. I am a marine mechanic on the Greek island of corfu, and the car belongs to a customer who also happens to own a garage in the UK. He managed to fit an incorrect slave to get him out of a bind (parts are hard to find here), and I agreed to a package of work specified by him (new head, steering box, timing belt, slave cyl) so the only part of the clutch hyd system replaced is the slave cyl. It actually worked perfectly before, but it was the wrong one.

So the only part replaced is the slave.

But......!! having messed around for hours and eventually got it half working as described above, I tried the 24hr pedal depressed trick again. And... wait for it..... perfect Case closed, thanks for your help folks.

rosssavage said:

Well that is a long story.... in a nutshell it's not my vehicle. I am a marine mechanic on the Greek island of corfu, and the car belongs to a customer who also happens to own a garage in the UK. He managed to fit an incorrect slave to get him out of a bind (parts are hard to find here), and I agreed to a package of work specified by him (new head, steering box, timing belt, slave cyl) so the only part of the clutch hyd system replaced is the slave cyl. It actually worked perfectly before, but it was the wrong one.

So the only part replaced is the slave.

But......!! having messed around for hours and eventually got it half working as described above, I tried the 24hr pedal depressed trick again. And... wait for it..... perfect Case closed, thanks for your help folks.

Click to expand...

Nice one mate!!

Its 2024 but Google brought me here whilst having a similar problem with my Discovery 3 Clutch Pedal. Eureka this gave me lots of ideas but finally resolved by a different approach and without spending a not inconsiderable fortune on a Clutch master Cylinder. After losing brake fluid due to a caliper leak I needed to bleed both brakes and clutch but after bleeding the clutch the pedal no longer returned and operated only on the final bit of pedal travel but not sufficient to disengage the clutch. Ultimately I decided that the master cylinder piston was not returning correctly although the pedal could be pulled up by hand! This was resolved by pressure bleeding in reverse through the slave cylinder bleed point at 17psi. The pressure of the reversing fluid was sufficient to return the master cylinder piston to the correct initial position allowing a full pedal stroke to then disengage the clutch. thereafter the piston is returned by the clutch acting on the slave cylinder. No 50 pedal pumps (this didn't work anyway), No parking on a hill no dismantling cylinders and no new master cylinder! Hope this helps someone some day!

This slave cylinder is also used in the Hillman Imp, 1st introduced in 1963, they are always bled with the slave cylinder off the mounting, just a small amount of air can prevent them from working as once the engine gets warm any air left in there expands meaning you have to pump the peddle to clear the clutch. In this case LandRover has proved a useful source of parts for the Imp fraternity to keep our cars on the road.