Abstract: Watertight sealed type electric motor 10, with a clearance between a core wire and a cover 24 of a lead wire 20, which is a vent path between the interior of the motor 10 and the outside, which clearance is covered a vent filter 28, which permits only gas to pass therethrough, and is attached to the lead wire 20 so as to cover an opening end portion of the cover 24.

Abstract: A tilt-trim device (17) for a marine propulsion unit comprises a cylinder means 18 with a rod guide (29) is fixed to the end portion of an outer cylinder (22) a piston (23)fixed to one end portion of a piston rod (24)is freely slidably disposed within an inner cylinder (21) and a hydraulic fluid is filled within the cylinder; and the piston rod passes through the rod guide; a tank device (20) in which the hydraulic fluid can be stored; and a pump device (19) intended to supply into and discharge from the cylinder device the hydraulic fluid within the tank device, thereby causing the expansion and contraction operation of this cylinder device. In this tilt-trim device, each of the inner and outer cylinders is made of pipe material, and the end portion of the outer cylinder is bent inwardly, whereby the rod guide is fixed to the outer cylinder by bent portion(30).

Abstract: In a tilt device 20 for a marine propulsion unit, a motor 61 is secured on a valve block 65 through an end plate 72, a tank chamber 75 forms a tank housing 74 covering a yoke 70 of the motor 61, a pump chamber 67 for the pump 62 in the valve block 65 and the tank chamber 75 are inter-connected through an oil passage 76 formed in the end plate 72.

Abstract: Tilt and trim cylinders have blind-end chambers connected through a main valve to a first port of a reversible pump. The rod-end chamber of the tilt cylinder is connected through the main valve to a second port of the reversible pump. The rod-end chamber of the trim cylinder is connected to an oil tank. The second port of the pump is connected to the oil tank, and the first port may be connected to either only the main valve or the oil tank through a suction-prevention valve, an orifice, or a pressure relief valve. When the pump is actuated with the tilt cylinder locked to keep an outboard engine in an tilted-up position, the trim cylinder is automatically contracted to withdraw its piston rod. Cavitation in an oil passage from the blind-end chamber of the trim cylinder to the pump is prevented when working oil is introduced from the oil tank to the pump through the orifice or the pressure relief valve.