Cylinder head cover with oil separator

A cylinder head cover for covering a cylinder head of a combustion engine, the cylinder head cover defining a plane adapted to extend over the cylinder head, the cylinder head cover including a housing defining a first chamber and a second chamber and an oil separator providing fluid communication between the first chamber and the second chamber of the housing, the oil separator comprising:

• at least one flow-through tube having an inlet and an outlet, the at least one flow-through tube defining a longitudinal axis that is not perpendicular to the plane defined by the cylinder head cover;
• and
• at least one spiral segment disposed within the at least one flow-through tube, the at least one spiral segment comprised of thread surfaces that, together with an inner surface of the at least one flow-through tube, define at least one spiral flow path between the inlet and the outlet of the at least one flow-through tube.