Abstract: A hull mounted, steerable marine drive system having trim actuation is both steerable through 360 degrees and is trimmable. The marine drive system includes a watertight enclosure assembly for sealing the hull, which is adapted for keeping much of the marine drive system from being exposed to water. The enclosure includes a gasket flange plate, a retention plate and a folded gasket. The gasket flange plate closely follows the contour of the hull and enhances the hydrodynamic and wake performance of the present marine drive system. Further, marine drive system includes a forward-neutral-reverse (FNR) transmission assembly, a drive unit assembly having a trimmable upper unit and a steerable lower unit, a steering actuator assembly, a trim actuator assembly, and, preferably, trim foils for providing enhanced negative and positive trim and for providing enhanced positive and negative lift.

Abstract: A breakaway skeg for the lower portion of a marine propulsion unit is disclosed. The skeg is designed such that the attachment features will fail under certain load or impacts, thereby preventing damage to the lower portion of the marine propulsion unit. The breakaway skeg is attached via shear tabs that include a relief that accounts for at least a part of the volume of the base portion of the shear tab. The shear tabs are designed to fail under certain circumstances before other components of the marine propulsion.

Abstract: A hull mounted, steerable marine drive system having trim actuation is both steerable through 360 degrees and is trimmable in a range of from approximately +3 degrees to approximately ?15 degrees. The marine drive system includes a watertight enclosure assembly for sealing the hull, which is adapted for keeping much of the marine drive system from being exposed to water. The enclosure includes a gasket flange plate, a retention plate and a folded gasket. The gasket flange plate closely follows the contour of the hull and enhances the hydrodynamic and wake performance of the present marine drive system. Further, marine drive system includes a forward-neutral-reverse (FNR) transmission assembly, a drive unit assembly having a trimmable upper unit and a steerable lower unit, a steering actuator assembly, a trim actuator assembly, and, preferably, trim foils for providing enhanced negative and positive trim and for providing enhanced positive and negative lift.

Abstract: A hull mounted, steerable marine drive system having trim actuation is both steerable through 360 degrees and is trimmable in a range of from approximately +3 degrees to approximately ?15 degrees. The marine drive system includes a watertight enclosure assembly for sealing the hull, which is adapted for keeping much of the marine drive system from being exposed to water. The enclosure includes a gasket flange plate, a retention plate and a folded gasket. The gasket flange plate closely follows the contour of the hull and enhances the hydrodynamic and wake performance of the present marine drive system. Further, marine drive system includes a forward-neutral-reverse (FNR) transmission assembly, a drive unit assembly having a trimmable upper unit and a steerable lower unit, a steering actuator assembly, a trim actuator assembly, and, preferably, trim foils for enhancing lift to assist in getting the boat up on plane.

Abstract: A replaceable nose section for a marine propulsion unit is disclosed. The marine propulsion unit includes a lower gear case that extends into the water and includes a lower portion that includes a shaft section, a prop section, and a nose section. The shaft section defines a first volume. The nose section includes an intermediate section that includes an intermediate bulkhead that defines a second volume. A nose cone is threaded to the intermediate section and defines a third volume such that the first and third volumes are not in fluid communication.

Abstract: A breakaway skeg for the lower portion of a marine propulsion unit is disclosed. The skeg is designed such that the attachment features will fail under certain load or impacts, thereby preventing damage to the lower portion of the marine propulsion unit. The breakaway skeg is attached via shear tabs that include a relief that accounts for at least a part of the volume of the base portion of the shear tab. The shear tabs are designed to fail under certain circumstances before other components of the marine propulsion.

Abstract: A hull mounted, steerable marine drive system having trim actuation is both steerable through 360 degrees and is trimmable in a range of from approximately +3 degrees to approximately ?15 degrees. The marine drive system includes a watertight enclosure assembly for sealing the hull, which is adapted for keeping much of the marine drive system from being exposed to water. The enclosure includes a gasket flange plate, a retention plate and a folded gasket. The gasket flange plate closely follows the contour of the hull and enhances the hydrodynamic and wake performance of the present marine drive system. Further, marine drive system includes a forward-neutral-reverse (FNR) transmission assembly, a drive unit assembly having a trimmable upper unit and a steerable lower unit, a steering actuator assembly, a trim actuator assembly, and, preferably, trim foils for enhancing lift to assist in getting the boat up on plane.