Engine cooling water passage structure and gas/liquid separator for engine cooling system

摘要

An engine cooling water passage structure includes a cooling water passage unit that is formed by integrating a water pump for supplying cooling water, a thermostat housing for housing a thermostat, a gas/liquid separation chamber for separating air from the cooling water, cooling water supply passages for supplying to water jackets, via the thermostat housing and the water pump, the cooling water that has been returned from a radiator, cooling water discharge passage for discharging into the radiator the cooling water that has passed through the water jackets, and a bypass passage for returning to the thermostat housing the cooling water that has passed through the water jackets, while bypassing the radiator. This cooling water passage unit is detachably mounted as a unit on an engine main body. Thus, the arrangement allows the engine cooling system to be made compact.