INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To efficiently introduce blow-by gas into an intake passage during natural intake and during supercharging in an internal combustion engine which has a supercharger in the intake passage.SOLUTION: An internal combustion engine 1 having a supercharger 3 in an intake passage 30 is provided which comprises: an oil tank 60 communicating with a crank chamber 17; a scavenge pump 63 transporting fluid in the crank chamber to the oil tank; a first blow-by passage 76 providing communication between an upper space 72 above the liquid level in the oil tank and a portion downstream from the supercharger in the intake passage; a second blow-by passage 77 providing communication between the upper space and a portion upstream from the supercharger in the intake passage; and a PCV valve 82 which is provided in the first blow-by passage and allows only a flow of the fluid directed from the upper space to the intake passage.