Abstract: In an outboard motor, a lower casing is located below an upper casing, and an engine with a vertically-arranged crankshaft is mounted above the upper casing. The rotation of the crankshaft is transmitted to a drive shaft pivotally supported in the upper casing, has its speed changed by a transmission mounted on the drive shaft, and is transmitted to a propeller shaft pivotally supported in the lower casing. The upper casing includes an upper-side casing and a lower-side casing, and mating surface portions of the upper-side casing and the lower-side casing are laterally wider than an upper section and a lower section of the upper casing.

Abstract: An outboard motor includes a lower casing provided below an upper casing, amounting plate provided above the upper casing, and an engine with a vertically-arranged crankshaft mounted on the mounting plate. The rotation of the crankshaft is transmitted to a drive shaft that is pivotally supported in the upper casing, changed in speed by a transmission mounted on the drive shaft, and transmitted to a propeller shaft that is pivotally supported in the lower casing. The outboard motor has upper mounts and lower mounts arranged to mount the outboard motor on a hull. The upper mounts are disposed on upper lateral surfaces of the upper casing, and the lower mounts are disposed on lower lateral surfaces of the upper casing. The outboard motor simplifies the upper casing for disposing a transmission therein and assembly and maintenance thereof.