Water jet propulsion unit

Abstract

A water jet propelled watercraft having a hull defining a downwardly facing water inlet opening and a jet propulsion unit contained within the hull and having a water inlet opening portion through which water is drawn, an impeller portion containing an impeller for drawing the water and a discharge nozzle portion through which the water pumped by the impeller is discharged for powering the watercraft. The jet propulsion unit is supported for pivotal movement within the hull about a transversely extending horizontal axis. The water inlet opening of the jet propulsion unit water inlet portion and a corresponding portion of the hull water inlet opening are defined by mating flanges that lie in a plane that contains the horizontal pivotal axis to minimize sealing pressure variations on the seal therebetween. A screen is positioned over the water inlet opening of the jet propulsion unit and tapers and curves downwardly to end at the undersurface of the lower side of the hull so that foreign material separated from the incoming water by the screen can easily flow backwardly along the bottom of the hull for removal during movement of the watercraft. The jet propulsion unit is also rotatable about a longitudinally extending axis and the defining flange of the water inlet portion is narrower at the front than the rear to permit rotational movement with a minimum of clearances.