What I can’t understand is that if it was the master cylinder only pushing fluid one way and not allowing fluid to return to the cylinder, the clutch pressure plate would have been held 'open' and you would have had massive clutch slip or complete loss of drive. I’d suspect something wrong with the pressure plate and as YB has said, at 180,000kms, you really should have fitted a new one - it surely cant have much life left in it by now anyway. Why not rig up the 5th cylinder but not fit it to the 'box. Bleed it out and then depress pedal carefully and after it has expanded, see if you can push the bearing back to confirm that the master cylinder is allowing fluid to return to the reservoir. If it is, your trouble is at the other end - pressure plate or DMF. Can you post a picture of the clutch pressure plate - particularly the fingers. Past: FL2 TD4 HSE Auto
Evoque SD4 Dynamic Lux Auto
Present: Audi A3 S Line.

I'm picking up a new clutch kit tomorrow but I'm ordering the master cylinder from eBay, so I'll wait for that to come before I fit the clutch ect, just wondering will the clutch kit come with the black plastic pipe with the bleed nipple on the end?

Just picked up the clutch kit, the man who served me said he wasn't sure if it was the right one for my car has one is self adjusting and one isn't? Lol

and .........................? FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

Fitted today and I now have a few other problems if you see my latest post