A water diverter for outboard marine motors is presented. In one embodiment, the water diverter is adapted to be secured to a transom bracket which includes a portion adapted to be mounted on a boat transom. The water diverter includes a body and a bracket. The body has a horizontal deflection plate with a triangular shape. Two vertical deflection plates extend upward along the edges of the horizontal deflection plate. The bracket includes a horizontal mounting surface having a triangular shape. Two vertical attachment walls extend downward along the sides of the horizontal mounting surface. The bracket is sized to fit within the body with alignment of attachment openings of the vertical deflection plates and attachment holes of the vertical attachment walls determining a fastener-based selectively adjustable vertical displacement between the horizontal deflection plate and the horizontal mounting surface.