Water-cooled type internal combustion engine

摘要

A water-cooled type internal combustion engine includes a cylinder provided in a cylinder block of an engine body and having a piston slidably received therein, and a cooling water passageway defined in the engine body and including a cooling water portion surrounding the cylinder. In the water-cooled type internal combustion engine, a through-bore is provided at that portion of an outer wall of the engine body which faces the cooling water passageway, a vibration absorbing means is mounted to the outer wall surface of the engine body to close the through-bore. The vibration absorbing means includes a resilient membrane which is disposed so that its peripheral edge does not protrude from an inner surface of the outer wall into the cooling water passageway, and which has one surface facing the cooling water passageway and the other surface facing a space area.