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Honda GX390 389cc GX OHV Air Cooled Engine
- $368.00
- Brands Honda
- Product Code: GX390UT2QNE2
- Availability: In Stock
Honda GX390 389cc GX OHV Air-Cooled 4-Stroke Horizontal Engine Product Overview The Honda GX390 389cc OHV Air-Cooled 4-Stroke Horizontal-Shaft Engine is a heavy-duty gasoline power unit designed for demanding commercial, agricultural, construction, landscaping, and industrial applications. As part of Honda's well-established GX Series, the GX390 combines a 389cc single-cylinder engine, overhead-..
Honda GX390 Horizontal GX Series Engine Features
Honda GX390 389cc GX OHV Air-Cooled 4-Stroke Horizontal Engine
Product Overview
The Honda GX390 389cc OHV Air-Cooled 4-Stroke Horizontal-Shaft Engine is a heavy-duty gasoline power unit designed for demanding commercial, agricultural, construction, landscaping, and industrial applications. As part of Honda's well-established GX Series, the GX390 combines a 389cc single-cylinder engine, overhead-valve technology, and air-cooled operation to deliver dependable power for a wide range of equipment.
Its horizontal-shaft design makes it suitable for machinery engineered around a horizontal PTO arrangement, including pumps, pressure washers, generators, compactors, tillers, and other utility equipment.
Key Features
- 389cc GX390 engine provides substantial power for demanding equipment.
- Single-cylinder OHV configuration is designed for efficient combustion and dependable operation.
- 4-stroke gasoline design uses a separate engine-oil lubrication system.
- Air-cooled system helps maintain appropriate operating temperatures.
- Horizontal PTO shaft accommodates a wide range of compatible machinery.
- Durable GX Series construction is designed for commercial and professional applications.
- Large displacement provides strong torque for equipment operating under load.
- Straightforward mechanical design makes routine service and maintenance practical.
- Available in different configurations depending on model, including starting and shaft options.
Product Specifications
| Specification | Details |
|---|---|
| Brand | Honda |
| Engine Series | GX Series |
| Engine Model | GX390 |
| Product Type | Horizontal-Shaft Gasoline Engine |
| Displacement | 389cc |
| Cylinder Configuration | Single Cylinder |
| Engine Cycle | 4-Stroke |
| Valve Train | OHV |
| Cooling System | Air-Cooled |
| Fuel Type | Unleaded Gasoline |
| Bore × Stroke | 88 × 64 mm |
| Starting System | Configuration-dependent |
| Shaft Orientation | Horizontal |
| Rated Speed | 3,600 rpm* |
| Maximum Power | Approx. 11.7 hp at 3,600 rpm* |
| Rated Power | Approx. 10.2 hp at 3,600 rpm* |
| Application | Commercial, agricultural, construction, industrial, and utility equipment |
*Horsepower figures and ratings can vary according to the applicable testing standard and exact engine configuration.
389cc GX390 Power
The GX390's 389cc displacement provides the capacity needed for equipment that demands considerably more power and torque than smaller utility engines.
Its single-cylinder design keeps the power unit relatively straightforward, while the large displacement allows it to handle applications involving pumps, generators, compactors, and other equipment operating under significant loads.
OHV 4-Stroke Technology
Honda's overhead-valve (OHV) design positions the valves above the combustion chamber to support efficient airflow and combustion.
The 4-stroke configuration uses separate intake, compression, power, and exhaust strokes. Unlike 2-stroke engines, the GX390 does not require gasoline and engine oil to be mixed together for normal operation.
Air-Cooled Design
The GX390 uses an air-cooled system, eliminating the need for a liquid radiator and coolant circuit. Engine airflow and cooling fins help dissipate heat during operation.
For reliable cooling performance, the engine's cooling areas should be kept clean and free of accumulated grass, dust, mud, and other debris.
Horizontal-Shaft Configuration
The horizontal PTO shaft allows the GX390 to power equipment specifically designed around horizontal-output engines.
Typical applications include:
- Water pumps
- Pressure washers
- Portable generators
- Tillers and cultivators
- Plate compactors
- Construction equipment
- Agricultural machinery
- Landscaping equipment
- Industrial equipment
- Specialty utility machinery
When replacing an existing engine, compatibility should be checked using more than displacement alone. Shaft diameter, shaft length, keyway dimensions, shaft rotation, mounting pattern, and shaft-centerline height are all important.
Commercial & Utility Applications
The GX390 is designed for applications where reliable power and durability are important. Its relatively large displacement makes it suitable for equipment that may experience substantial or continuous loads.
The engine can serve as an original equipment power source or, when all specifications match, as a replacement for compatible machinery.
Maintenance-Friendly Design
Regular maintenance is important for preserving engine performance and service life. Typical maintenance tasks include:
- Checking and changing engine oil
- Servicing the air cleaner
- Inspecting the spark plug
- Cleaning cooling areas
- Maintaining the fuel system
- Inspecting the PTO shaft and mounting hardware
Maintenance intervals should always follow the instructions for the exact GX390 model.
Starting Configuration
The GX390 platform is offered in multiple configurations, so the starting system should not be assumed from the engine family name alone. Depending on the specific version, the engine may be supplied with recoil starting or electric starting.
If purchasing a replacement engine, confirm the complete model number and suffix to ensure the starting system and electrical components are compatible with the equipment.
Why Choose the Honda GX390?
The Honda GX390 provides a strong combination of 389cc displacement, OHV technology, air-cooled operation, 4-stroke efficiency, and horizontal-shaft versatility.
Its durable design makes it a practical power source for professional equipment and demanding utility applications where dependable engine performance is important.
Installation & Compatibility
Before purchasing, compare the engine's specifications with the original equipment. Pay particular attention to:
- Full engine model and suffix
- PTO shaft diameter
- PTO shaft length
- Keyway dimensions
- Shaft rotation
- Mounting-hole pattern
- Shaft height
- Governor configuration
- Throttle controls
- Exhaust arrangement
- Fuel-system configuration
- Starting and charging system
- Overall engine dimensions
Important Specification Note
Although 389cc is the standard displacement associated with the Honda GX390, exact specifications can vary between model configurations and markets. Horsepower ratings, shaft dimensions, fuel-tank configuration, starting system, and electrical equipment should therefore be verified using the complete Honda GX390 model number before publishing a detailed product listing or ordering a replacement engine.