The document provides instructions for disassembling and assembling the piston motor for a 303.5 Mini Hydraulic Excavator. It lists 48 steps to disassemble the various components of the motor including removing gears, seals, springs, pistons, and housing pieces. It also provides notes on cleaning parts and applying oil before assembly. The assembly procedure is listed as reversing the disassembly steps and replacing all O-rings and seals.