The Mini clutch slave cylinder is a vital link in the proper operation of the Mini clutch. The master cylinder feeds the slave cylinder to exert the mechanical pressure to disengage the clutch. The simple sounding process is complicated by a worn cylinder. As the wear continues it first will probably bypass, meaning that the clutch will not stay disengaged when holding the pedal down. The next more obvious sign is when you actually see fluid leaking! The slave cylinders are easy to replace. The cylinder bore size is 7/8" diameter.
It's easy to know if you have a Verto or the original type. The Verto slave has a tab in the casting for a return spring, and uses a "Banjo" style hose to the cylinder body. This original style unit mounts at the top of the flywheel housing, and acts on the longer (6-8 inches) throw out arm.