An internal combustion engine with a noise-suppressing encapsulation has a drive wheel for auxiliary units which is driven by the crankshaft of the engine and arranged outside the encapsulation. The drive wheel consists of two concentric parts which are connected via at least one elastic member. The inner part of the drive wheel has cooling air ducts which extend from inlet ends on the side opposite an opening in the encapsulation wall to a exit ends on the side adjacent the opening, the exit ends being spaced a greater distance from the axis of rotation than the inlet ends, although still lying within the noted opening. Thus a blower is provided in the form of a centrifugal pump. A cover is connected to the outer part of the drive wheel which covers the inner part and has sound-isolated suction openings for the cooling air.