Honda GX Series Engines

How to Choose a Honda GX Series Engine

The GX series spans several displacement classes, so size the engine to the load it has to drive, not just the equipment it bolts to. Confirm these specs before ordering:

• Displacement and horsepower: The model number tracks displacement — GX160 is roughly 163cc, GX240 about 270cc (4.8 HP class), GX270 about 270cc (8.5 HP class), and GX390 about 389cc (11.7 HP class). Verify the gross HP rating against the pump or pulley load it will turn.
• Shaft type and diameter: Honda offers tapered, straight keyed, and threaded shafts in common diameters such as 3/4", 20mm, and 1". Match the shaft to your coupling, clutch, or pump mount.
• Shaft length and rotation: Confirm shaft length and counterclockwise (PTO-end) rotation so the engine mates to the driven component.
• Starting and fuel options: Recoil or electric start, and standard tank versus oil-alert or low-oil shutdown features.
• Mounting pattern: Check the bolt circle and base footprint so it drops onto your existing frame or hydraulic power unit.

Which Honda GX Engine Is Right for the Job?

Move up the displacement ladder as the load grows. The Honda GX160 Series Engines suit smaller pumps, compactors, and light pressure washers. The Honda GX240 Series Engines and Honda GX270 Series Engines share a displacement class and step up torque for mid-size hydraulic power units, generators, and larger pumps. The Honda GX390 Series Engines deliver the most power in the GX lineup for heavy log splitters, high-flow pumps, and demanding continuous-duty work. When you are unsure, match the engine to the rated input HP of the driven device and leave headroom for full-load operation. Browse the full Honda Engines range for adjacent models and accessories.

Complete the System

A GX engine is the prime mover — pair it with the right driven components to build a working unit. Couple it to Hydraulic Pumps for a gas-powered power unit, drive Hydraulic Motors in the circuit, and actuate Hydraulic Cylinders on splitters, presses, and lifts. For exhaust replacement and noise control, see Mufflers sized to the GX frame.

Cross-Referencing an Obsolete Honda GX Engine

If an older GX engine, a discontinued shaft configuration, or an engine on a legacy OEM machine is no longer available, we can help you find the current equivalent. Honda has revised shaft offerings and model designations over the years, so a side-by-side spec match — displacement, shaft type and diameter, length, rotation, and mounting — is the surest way to confirm fit. Northern Hydraulics has cross-referenced engines and hydraulic components since 1963; send your old model number, the equipment it powers, and a photo of the shaft and mount, and request a cross-reference.