Opening the bleed screw and trying the pedal will get you to an answer sooner, and will rule out the clutch hydraulics as the potential issue. In my case I was in no hurry with my car as it had been off the road so long the clutch wasn’t high on my to do list, so could afford to wait on the hunch the clutch plunger/arm was seized (often is the case).
The clutch pedal is mechanically connected to the clutch master cylinder which in turn is connected to the slave cylinder (the bit the clutch arm is connected to), these are connected via a metal pipe and a rubber hose. Normally as you push the clutch pedal pressure is built up in the system (via the clutch master cylinder - think of this as a pump) which forces brake fluid down the pipe and hose into the clutch slave cylinder, the slave cylinder then pushes the rod outwards which operates the clutch arm. If you have a blockage in the clutch hydraulics (eg collapsed hose etc), then the pedal could go rock hard (think of putting your thumb over a hose pipe - the pressure builds up and it has nowhere to go).
I myself in 12 years of being around/working on Minis have never come across an issue with clutch hydraulics causing a rock hard pedal (usually pedal goes soft - clutch drag), but I’m not saying it can’t happen, so would be well worth ruling this out.
There is a potential of introducing air into the clutch hydraulics, so some precautions to avoid this can be taken. This is not the end of the world however as the clutch hydraulics are easy to bleed if needed.
Either have a helper press the pedal for you, or as I do find a piece of 4x2 or similar cut to size and wedge the pedal down wedging the wooden block between the pedal and seat (or cross member)
- First open the bleed screw on the clutch slave cylinder, you only need to open this like 1/2 a turn.
- Ask you assistant (or using the piece of wood) press the clutch pedal down
- Wait a second or so while some fluid is expelled.
- Tighten the bleed screw while the pedal is still pressed down.
- Once bleed screw has been tightened release the clutch pedal
If you find after trying the above the pedal goes down, but after tighten the bleed screw on the clutch slave the pedal goes hard again and can’t be pressed you know the issue is mechanical (likely seized clutch plunger/arm). If however the clutch pedal remained hard with the bleed screw open (in this case you may not see brake fluid expelled from the bleed screw when the pedal is pressed) then you know the issue is with the hydraulics.
Thanks for the very detailed explanation written in terms I understand .
I think I will continue to try the method of not turning the bleed screw for a few more days ,then if that doesn't work I will follow the instructions with someone helping me on the pedal.
Really appreciate the time you have taken and will return when I get to the next hurdle or success, might be a week or so
many thanks