Outboard motor

An outboard motor comprising:

• an engine having a vertically extending crankshaft;
• an oil pan disposed below a crankcase of said engine;
• a vertically extending drive shaft disposed to be driven by said crankshaft;
• a screw positioned at a lower end portion of said drive shaft, said screw extending perpendicularly to said drive shaft, said screw being disposed to be driven by said drive shaft through a gear transmission mechanism;
• a first case for housing therein said oil pan and an upper part of said drive shaft, said first case being disposed below said crankcase, said first case having a coupling surface coupled to said crankcase;
• a second case for housing therein a lower part of said drive shaft, said second case being disposed below said first case;
• a gear case for housing therein said gear transmission mechanism, said gear case being disposed below said second case;
• said first case having a vertical wall disposed therewithin to form an exhaust passage through which exhaust gas discharged from said engine passes, such that an outer wall of said oil pan is separated from said exhaust passage by said vertical wall;
• said second case having an upper edge portion coupled to a lower edge portion of said first case, said second case having a vertical wall disposed therewithin to form a cavity and an exhaust passage for discharging the exhaust gas into water.