20090090325 | Piston Skirt Oil Retention for an Internal Combustion Engine - An internal combustion engine is provided having a cylinder case with at least one cylinder bore wall defining at least one cylinder bore. At least one piston is reciprocally movable within the at least one cylinder bore. The at least one piston includes at least one skirt portion preferably having a barrel-shaped profile. The cylinder bore wall has an oleophobic characteristic, while the at least one skirt portion has an oleophilic characteristic. The oleophobic and oleophilic characteristic is produced by at least one of coating and machining the at least one cylinder bore wall and the at least one skirt portion, respectively. | 04-09-2009 |