Disassembly
1. Disassemble the unit without disassembling the piston.
Examination
2. Check the inside of the cylinder body for corrosion and scoring, the piston seal for wear or deformation, and the piston for corrosion and scoring.
3. If the clearance between the cylinder and piston exceeds the limit value (0.15 mm), replace the master cylinder and/or piston assembly.
4. Apply a layer of working fluid (DOT-3 brake fluid) to the inner surface of the master cylinder body and to the outer surface of the piston.
Installation
5. Install the piston assembly into place.