Abstract: An eccentric cam locking assembly includes an elongated locking bar having a first end portion and an opposite second end portion, a first fastening arrangement defined on the first end portion of the bar for mounting the bar on a stationary member of a seed planting implement and a second fastening arrangement defined on the opposite second end portion of the bar for clamping the bar on an eccentric cam that is mounted to the implement so as to rotate relative thereto to align the position of furrow closing wheels mounted on a swing arm extending from the rear of the seed planting implement. When installed, the locking assembly inhibits misalignment of the furrow closing wheels by providing additional resistance against unintended rotation of the eccentric cam. The second fastening arrangement is releasable so that the eccentric cam may be turned when the furrow closing wheels need to be aligned.