Internal combustion engine blow-by gas ventilation system

An internal combustion engine comprising:

• an engine casing having a crankcase and a separating plane along which the engine casing can be separated;
• a shaft disposed in the engine casing and having a shaft axis;
• at least one bearing supporting the shaft in the engine casing and permitting rotation of the shaft about the shaft axis;
• a separator wheel disposed on the shaft for rotation therewith, the separator wheel having a first opening in fluid communication with the crankcase, a second opening, and a channel extending radially from the second opening to the first opening relative to the shaft axis;
• a suction tube fluidly communicating with the second opening of the separator wheel, the suction tube being permanently affixed to a portion of the engine casing, an end of the suction tube having a unitary abutment surface;
• and
• a gasket disposed between the unitary abutment surface of the suction tube and the second opening of the separator wheel, the gasket being also disposed at least in part on the separating plane of the engine casing.