M8 Greyhound clutch problem

[Russell Boaler]

Dealing with fluid flow on a day to day basis I'd say that the size of the tubing is probably due to the amount of fluid that needs to be transferred. If the pipe is small you'd wind up with a pedal that is just slow to depress rather than a clutch that won't fully disengage. It would also mean a lot more pressure being needed at the master cylinder to push the fluid through the pipe (compared to the larger pipe) if depressing the clutch at normal speed. Maybe that increased pressure is causing some bypassing in the master cylinder?