I've just had a wrestle after changing the clutch slave cylinder on an MGB. Couldn't get pressure and couldn't find a leak so put in a new master as well. Still no joy after a bit of web searching I found that it wasn't unknown for air to get trapped behind the piston in the slave but in front of the bleed nipple so it remained after bleeding. Solution was to wedge the clutch pedal down the open the bleed nipple and force the piston as far back as possible. Right enough air bubbles were expelled and I now have a clutch that works as intended. I'm told these are the joys of our hobby and old cars!
