GX340/390

Description

The Next Generation of GX Engines.
With the GX340, you’re looking at one of the best engines in the business. More power. Quieter performance. Lower fuel consumption. Lower emissions. Better features. Exceptional performance. Honda’s GX series lives up to the legend, and then some.

COMMON APPLICATIONS

Pressure washers
Commercial lawn and garden equipment
Tillers / cultivators
Generators
Forestry equipment
Construction / industrial equipment
Agricultural equipment
Small vehicles
Water pumps

GX340

GX390

Engine Type Air-cooled 4-stroke OHV Air-cooled 4-stroke OHV
Bore x Stroke 88 X 64 mm 88 X 64 mm
Displacement 389 cm3 389 cm3
Net Power Output* 10.7 HP (8.0 kW) @ 3,600 rpm 11.7 HP (8.7 kW) @ 3,600 rpm
Net Torque 19.5 lb-ft (26.4 Nm) @ 2,500 rpm 19.5 lb-ft (26.4 Nm) @ 2,500 rpm
PTO Shaft Rotation Counterclockwise (from PTO shaft side) Counterclockwise (from PTO shaft side)
Compression Ratio 8.2:1 8.2:1
Lamp/Charge coil options 25W, 50W / 1A, 3A, 10A, 18A 25W, 50W / 1A, 3A, 10A, 18A
Carburetor Butterfly Float Type Butterfly Float Type
Ignition System Digital CDI with variable timing Digital CDI with variable timing
Starting System Recoil/electric Recoil/electric
Lubrication System Splash Splash
Governor System Centrifugal Mass Type Centrifugal Mass Type
Air Cleaner Dual element Dual element
Oil Capacity 1.16 US qt (1.1 L) 1.16 US qt (1.1 L)
Fuel Tank Capacity 6.4 U.S. qts (6.1 liters) 6.4 U.S. qts (6.1 liters)
Fuel Unleaded 86 octane or higher Unleaded 86 octane or higher
Dry Weight 69 lb (31.5 kg) 69 lb (31.5 kg)
Fuel Efficient, High Output Operation
  • Digital CDI ignition system with variable timing Learn More
  • Increased compression ratio
  • Precision camshaft design offers precise valve timing and optimal valve overlap for better fuel efficency
  • OHV design for increased efficiency and optimal power transfer
Smooth Performance
  • Precision engineered components result in lower vibration
  • Ball bearing supported crankshaft for greater stability
  • Heavy duty balancer shaft
  • Improved piston design
Exceptionally Quiet
  • Large capacity, multi-chamber exhaust system
  • Improved camshaft and muffler reduce overall engine noise by up to 5 dB
  • Reduced mechanical noise due to piston design
  • Forged steel crankshaft and rigid crankcase
  • Helical cut gears
  • Sophisticated air intake system
Proven Reliability
  • Oil Alert Learn More
  • Cast iron cylinder sleeve
  • High quality materials, fit, and finish
  • Dual element air cleaner
  • Fuel Valve
  • 3-Year Limited Warranty
Easy to Use and Maintain
  • Simple throttle control
  • Large fuel tanks
  • Large automotive type fuel cap
  • Dual oil drains and fill
  • Easy, convenient, heavy duty control box
  • Easily accessible spark plug
Easy Starting
  • Heavy duty recoil starter
  • Automatic mechanical de-compression system Learn More
  • Variable ignition timing
Emissions Compliant
  • CARB and EPA certified
  • No catalyst necessary
Available Options
  • Low profile versions
  • Gear reduction options
  • Electic start
  • Spark arrester available
  • Charge and lamp coils with multiple output options available
  • Cyclone Air Cleaner available