The document provides instructions for disassembling the piston pump (swing) of an M315C wheeled excavator. It describes removing 22 individual parts from the pump housing including the servo valve, charge pump, gears, head, port plate, relief valves, spool, and adjustment screw. Cleanliness is important when disassembling to prevent dirt from entering the internal mechanisms. Personal injury precautions are also noted regarding hydraulic pressure and spring force.