Abstract: A balancer shaft includes a shaft body, a driven gear, a fixed member fixed to the shaft body, and an elastic member located between the driven gear and the fixed body. A projection projects from the driven gear. The fixed member includes an accommodation recess accommodating the projection. The elastic member is arranged in the accommodation recess adjacent to the projection. The projection includes an abutment side surface, which includes an outer end. The outer end and the elastic member are spaced apart in the circumferential direction by a first distance when the abutment side surface and the elastic member are in abutment without elastically deforming the elastic member. The first distance is greater than a maximum value of an elastic deformation amount of the elastic member in the circumferential direction when the elastic member is pressed between the projection and a wall of the accommodation recess.

Abstract: A balancer shaft includes a shaft body, a driven gear, a fixed member fixed to the shaft body, and an elastic member located between the driven gear and the fixed body. A projection projects from the driven gear. The fixed member includes an accommodation recess accommodating the projection. The elastic member is arranged in the accommodation recess adjacent to the projection. The projection includes an abutment side surface, which includes an outer end. The outer end and the elastic member are spaced apart in the circumferential direction by a first distance when the abutment side surface and the elastic member are in abutment without elastically deforming the elastic member. The first distance is greater than a maximum value of an elastic deformation amount of the elastic member in the circumferential direction when the elastic member is pressed between the projection and a wall of the accommodation recess.

Abstract: An internal combustion engine includes: a case; an oil pan disposed below the case; an oil filter into which oil inside the oil pan flows; and a guide that guides oil flowing out from the oil filter and flowing down along a sidewall surface of the case, the guide projecting such that an end portion of the guide is positioned outside a sidewall surface of the oil pan.

Abstract: An internal combustion engine includes: a case; an oil pan disposed below the case; an oil filter into which oil inside the oil pan flows; and a guide that guides oil flowing out from the oil filter and flowing down along a sidewall surface of the case. The guide includes a projection that is provided continuously in a transverse direction in the sidewall surface of the case and extends so as to project outside the case from the sidewall surface, a descending portion that is extended downward from an outer peripheral edge of the projection, and a collecting portion that is positioned in a lower end edge of the descending portion and collects the oil that flows along the sidewall surface of the case downwardly from the projection through the descending portion.

Abstract: An internal combustion engine includes: a case; an oil pan disposed below the case; an oil filter into which oil inside the oil pan flows; and a guide that guides oil flowing out from the oil filter and flowing down along a sidewall surface of the case, the guide projecting such that an end portion of the guide is positioned outside a sidewall surface of the oil pan.

Abstract: An internal combustion engine includes: a case; an oil pan disposed below the case; an oil filter into which oil inside the oil pan flows; and a guide that guides oil flowing out from the oil filter and flowing down along a sidewall surface of the case. The guide includes a projection that is provided continuously in a transverse direction in the sidewall surface of the case and extends so as to project outside the case from the sidewall surface, a descending portion that is extended downward from an outer peripheral edge of the projection, and a collecting portion that is positioned in a lower end edge of the descending portion and collects the oil that flows along the sidewall surface of the case downwardly from the projection through the descending portion.