Our 139-cc 4-hp portable outboard mirrors our OHV F6, with a couple less horses. It features the same ergonomic, easy-grip starter handle with a built-in decompression device for effortless starts. The F4 also features a built-in fuel tank with the option of switchable access to an additional external tank for amazing extended range. There’s no stopping this little brute.
Engine Type: 1 cyl.
Bore x Stroke: 62 x 46mm (2.44 x 1.81in)
Prop Shaft Horsepower: 4hp at 4500 RPM
Full Throttle RPM Range: 4000 - 5000 RPM
Alternator Output at W.O.T.: 6 Amp
Compression Ratio: 8.9:1
Fuel Induction System: Carb
Weight*: 27 kg (59 lbs) - 28 kg (61 lbs)
Recommended Fuel: Octane 87
Recommended Engine Oil: Yamalube® 4M (See owner's manual)
Recommended Fuel Filtration: N/A
Warranty: Limited 3-year Pleasure, 3-year Government, 1-Year Commercial