This compact four HP engine from Honda delivers power and responsiveness with a convenient recoil start. As an OHV commercial-grade engine, this model is ready to go to work in a wide range of common applications. This part is compliant with EPA/CARB standards and carries a three year commercial warranty. Weighing just 30 lbs., it can be effectively used in many vehicles and appliances.

Honda’s GX series engines are known for superior reliability and performance, and the GX120 continues that reputation. It delivers strong power with lower noise, reduced vibration, and lower emissions without sacrificing output.

Fuel-efficient, high-output operation is achieved through a precision camshaft design for optimal valve timing and overlap, plus an OHV design for improved efficiency and power transfer. A high compression ratio further improves fuel economy.

Smooth performance comes from precision-engineered components, a ball-bearing-supported crankshaft for stability, and reduced vibration throughout operation.

Exceptionally quiet design includes a multi-chamber exhaust system, lightweight noise-reducing materials, a rigid crankcase, forged steel crankshaft, helical-cut gears, and a refined air intake system.

Proven reliability features include Oil Alert, protective carburetor coating and filter, cast iron cylinder sleeve, dual-element air cleaner, fuel valve, and high-quality materials and construction.

Easy to use and maintain with simple throttle control, large fuel tank with automotive-style cap, dual oil drains/fill, accessible spark plug, and a heavy-duty control bo(more...)

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• Engine type: Air-cooled 4-stroke OHV
• Starting sytem: Recoil starter
• Shaft: 3/4" solid keyed
• Bore x stroke: 60 x 42 mm
• Displacement: 118 cm3
• Net power output: 3.5 HP (2.6 kW) @ 3600 rpm
• Net torque: 5.4 lb-ft (7.3 Nm) @ 2500 rpm
• PTO shaft rotation: Counterclockwise from PTO shaft side
• Compression ratio: 8.5 : 1
• Lamp/Charge coil options: 25W, 50W
• Carburetor: Butterfly
• Ignition system: Transistorized magneto
• Lubrication system: Splash
• Governor system: Mechanical
• Air cleaner: Dual element
• Oil capacity: 0.59 US qt. (0.56 L)
• Fuel tank capacity: 2.1 US qts (2.0 liters)
• Fuel: Unleaded 86 octane or higher
• Dry weight: 29 lbs (13.0 kg)
• Dimensions: 11.7 in long x 13.6 in wide x 13.0 in high (297 x 346 x 329 mm)
• Warranty: 3 year commercial warranty (limited to manufacturer defects)