A locking device for connecting and disconnecting the top portion and tray of a cowling of an outboard motor. A locking mechanism comprising a pair of guide members each having a bore, one affixed to the top cowling and the other affixed to the cowling tray such that the guide member bores are adjacent to and aligned with one another when the top cowling is fitted onto the tray. A movable member is slidably supported within the top cowling guide member bore and has an outer portion that is biased outward by a spring for engagement with the tray guide member bore. An inner wire slidably supported within an outer sheath interconnects the movable member with a release lever that is rotatably supported on the upper surface of the top cowling. Upward movement of the lever causes the movable member to retract into the top cowling guide member bore against the force of the spring and disengage with the tray guide member bore so that the top cowling may be unlocked and detached from the tray.