| 摘要 |
PURPOSE:To reduce production of the change in the axial tension of a head bolt and to maintain sealing ability of a mating face between a block and a head, by a method wherein a space is engaged with the upper part of the interior of a cylinder head bolt insertion hole, and an unloaded hole part is formed in the bolt hole of a cylinder block. CONSTITUTION:A bolt insertion hole 4 is formed in a cylinder head 3 made of an aluminum alloy, a bolt hole 2 is formed in a cylinder block 1 made of cast iron, and the cylinder head 3 and the cylinder block 1 are fastened together by means of a head bolt 5. A spacer 6 is engaged with the upper part of the bolt insertion hole 4 of the cylinder head 3, and an unloaded hole part 2a with a given depth is formed in the upper end part of the bolt hole 2 of the cylinder block 1. The spacer 6 is formed by a material having a linear expansion factor lower than that of the head bolt 5. This constitution enables reduction of the change in axial tension of the head bolt, prevention of setting of a mating face between the cylinder block and the head, and ensurance of sealing ability. |
