The 4 HP Honda Engine with gear reducer provides the power you need while offering an effective and reliable performance. The built-in 6:1 gear reducer and recoil start are designed to make it even more efficient. Common applications include pumping, operating pressure washers, and tillers or cultivators. The 4 HP Honda Engine offers a versatile array of ways it can be used.

4.0 HP gas engine with built-in 6:1 gear reduction. Honda’s GX series engines are known for superior reliability and performance, and the GX120 delivers strong output with lower noise, reduced vibration, and lower emissions.

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

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

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

Proven reliability includes Oil Alert, carburetor protective coating and filter, cast iron cylinder sleeve, dual-element air cleaner, and fuel valve, all built with high-quality materials and fit/finish.

Easy to use and maintain with simple throttle control, large fuel tank with automotive-style cap, dual oil drains/fill, and easily accessible spark plug.

Easy starting is supported by a heavy-duty recoil starter, ergonomic rope handle, and automatic mechanical decompression system.

Emissions compliant with CARB and EPA certification, delivering lower emissions without reduced power and no catalyst required.

• Engine type: Air-cooled 4-stroke OHV
• Starting sytem: Recoil starter
• Shaft: 3/4" solid keyed
• Built in 6:1 gear reduction
• 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)