Abstract: A deaerator device has a tubular casing and an internal helical blade defines an axial opening through the center thereof toward which entrained gas bubbles will converge as a fluid travels through the casing. A vent pipe collects the gas bubbles at the opening and communicates them away from the casing.

Abstract: A means for separating gases from coolant fluid in an engine cooling system is provided. The gas-liquid separator means utilizes a double chamber design, with the double chamber symmetrically placed on opposite sides of a flow access from the inlet to the outlet. Curved walls within the chambers of the gas-liquid separator create a centrifugal action which causes entrained gas to separate from the coolant fluid and flow to the center of curvature of the curved walls. In the first embodiment, the gas bubbles are then siphoned directly from the center of curvature to a radiator top tank of the cooling system by means of a conduit. In the second embodiment, a passage in the body of the gas-liquid separator intercommunicates the centers of curvature in each of the chambers whereby the gas bubbles are then drawn off from the passage through a conduit connected to the radiator top tank of the engine cooling system.