9. CYLINDER/PISTON MXU 550EXi/MXU500i Piston "IN" Mark Cylinder/Piston Clean any gasket material from the cylinder mating surfaces of the crankcase and oil passage. Apply engine oil to the piston pin. Apply engine oil to the connecting rod small end and piston pin hole. Install the piston with the "IN" mark face intake side and piston pin. Piston Pin Piston Pin Clip Place a clean shop towel over the crankcase prevent the clip from falling into the crankcase. Install the new pin clip. Make sure that the piston pin clips are seated securely. Do not align the piston pin clip end gap with the piston cut-out. Piston Piston Pin Gasket Dowel Pins Install the dowel pins and gasket. 9-8