| 摘要 |
PURPOSE:To prevent large reduction in lubricating oil pressure of an engine lubricating system by providing the oil relief ports for lifter parts in such a place as they do not communicate in conformity with lubricating oil passage so as to avoid abundant outflow of lubricating oil from the oil relief ports. CONSTITUTION:In a cylinder block 1 lifter bores 12 are formed, and in each of them a cup-shaped lifter part 13 for the mechanical valve lifter is inserted to be slidable. Further, the cylinder block 1 has a lubricating oil passage 19 opened toward the inner circumferential surfaces of the lifter bores 12 so as to be used also for that which uses hydraulic valve lifter. On the other hand, on each side circumferential wall of the lifter parts 13 a through hole 20 which is formed by the core print of a connecting core in the manufacturing process and purposed for discharging outward lubricating oil collected inside the lifter part 13 is provided. This communicating hole 20 is provided at the place where it does not communicate in conformity with lubricating oil passage 19 ranging through the total stroke at the normal operation of the lifter part 13. |
