Removal and Installation
First drain the brake fluid out of the master cylinder reservoir. To do this, attach a bleed tube to the bleed valve on the nearest front brake, open the bleed valve and operate the brake pedal until the master cylinder reservoir is empty.
Retighten the bleed valve.
Where applicable, disconnect the heater air intake flexible tube from the heater and from the wheel arch.
From inside the car, remove the split pin and withdraw the clevis pin securing the master cylinder push rod to the brake pedal .
Disconnect the hydraulic pipe union from the master cylinder.
Remove the two nuts and spring washers securing the master cylinder to the bulkhead and lift off the master cylinder.
Installation is a simple reversal of the removal procedure.
When installation is completed, bleed the braking system as detailed later in this section.

Seal Replacement

Remove the filler cap and drain out any remaining fluid from the reservoir. Detach the rubber boot from the end of the cylinder and slide it down the push rod. Extract the retaining circlip from the cylinder bore and remove the internal components, as shown in , from the cylinder. Remove the secondary cup from the piston.
Clean and inspect the components of the master cylinder as described in 'HYDRAULIC SYSTEM OVERHAUL. at the beginning of this section.
If the piston and bore are in good condition, lubricate the piston with clean brake fluid and assemble the secondary cup to the piston. The flat face of the seal must abut the end flange of the piston.
Fit the spring retainer into the small diameter end of the piston spring and insert the spring into the bore, large diameter first. Fit the main cup seal and the cup washer over the spring retainer. The main cup must be fitted carefully, lip edge first. Insert the piston assembly, then refit the push rod assembly and secure with the circlip. Refit the rubber boot on the end of the cylinder.