An agricultural machine comprises an operating unit and a carrier assembly for the operating unit. The carrier assembly includes a carrier arm and a suspension system that suspends the operating unit from its center point and allows the operating unit to rotate about an axis that extends in the working direction. A support mechanism supports the weight of the operating unit and allows the height of the operating unit arm to change. The support mechanism includes an actuator located on the axis of the operating unit and configured to adjust the height of the operating unit.