| 摘要 |
<p>An internal combustion engine comprises a cylinder block (10), an upper crankcase (14), and a lower crankcase (22), which comprises an inner casing (42) including an outer wall (41) and the lower main bearing housings (46), and an outer casing (44), with a space (56) therebetween. The outer casing (44) has a sump (81) mounted on it. Oil drainage passages from the cylinder head face of the cylinder block extend down to meet a pair of longitudinal passages (34, 36) from which oil drainage ports open into the space (56) between the inner and outer casings (42, 44). These passages add significantly to the stiffness of the engine.</p> |
