Honda GXV340

The Honda GXV340 is a 337 cc, (20.56 cu·in) natural aspirated single-cylinder four-stroke air-cooled internal combustion gasoline engine with a vertical shaft, manufactured by Honda Motor Company for general-purpose applications.

A 82.0 mm (3.23 in) cylinder bore and 64.0 mm (2.52 in) piston stroke give the GXV340 engine a total of 337 cc of displacement. The compression ratio rating is 7.7:1.

The GXV340 engine produced 11.2 PS (8.2 kW; 11.0 HP) at 3,600 rpm of maximum horsepower and 23.0 N·m (2.3 kg·m, 17 ft·lb) at 2,500 rpm of maximum torque.

The Honda GXV340 features:

• Overhead valve (OHV) design
• Transistorized magneto ignition system
• Horizontal type carburetor with butterfly valve
• Centrifugal governor
• Splash lubrication system
• Forced air cooling system
• Recoil or electric starter

General information

Engine Specifications
Engine model	GXV340
Engine type	4-stroke, OHV, single-cylinder
Displacement	337 cm3, (20.56 cu·in)
Max. horsepower	11.2 PS (8.2 kW; 11.0 HP) at 3,600 rpm
Max. torque	23.0 N·m (2.3 kg·m, 17 ft·lb) at 2,500 rpm
Cooling system	Forced air
Air cleaner	Dual-element type
Lubricating system	Splash
Ignition system	Transistorized magneto ignition
Fuel system	Horizontal type carburetor with butterfly valve
Fuel consumption	321 g/kWh (240 g/HPh, 0.53 lb/HPh)
Fuel tank capacity	2.3 L (0.61 US. gal. 0.51 Imp. gal.)
Fuel used	Unleaded gasoline (octane number 86 or higher)
Starting system	Recoil or electric starter
Stoping system	Ignition primary circuit ground
Governor	Centrifugal governor
PTO shaft rotation	Counterclockwise (from PTO shaft side)
Dimensions (L x W X H)	430 x 385 x 410 mm (16.9 x 15.2 x 16.1 in)
Dry weight	32.0 kg (70.5 lbs)

Cylinder Block and Head

Cylinder block
Compression ratio:	7.7:1
Cylinder bore:	82.0 mm (3.23 in)
Piston stroke:	64.0 mm (2.52 in)
Cylinder internal diameter (standard):	82.000 mm (3.2283 in)
Piston skirt outer diameter (standard):	81.985 mm (3.2277 in)
Number of piston rings (compression / oil):	2/1
Connecting rod big end diameter (standard):	36.025-36.039 mm (1.4183-1.4189 in)
Connecting rod small end diameter (standard):	20.005-20.020 mm (0.7876-0.7882 in)
Piston pin diameter:	19.994-20.000 mm (0.7872-0.7874 in)
Side clearance (Top):	0.030-0.060 mm (0.0012-0.0024 in)
Side clearance (Second):	0.030-0.060 mm (0.0012-0.0024 in)
Ring end gap (Top):	0.200-0.400 mm (0.0079-0.0157 in)
Ring end gap (Second):	0.200-0.400 mm (0.0079-0.0157 in)
Ring end gap (Oil):	0.200-0.700 mm (0.0079-0.0276 in)
Ring width (Top):	1.160-1.175 mm (0.0457-0.0463 in)
Ring width (Second):	1.160-1.175 mm (0.0457-0.0463 in)
Crankpin journal diameter:	35.975-35.985 mm (1.4163-1.4167 in)
Crankshaft center distance:	32 mm (1.26 in)
Cylinder head
Valve arrangement:	OHV, gear driven
Valves:	2
Valve steam diameter (INTAKE):	6.590 mm (0.2594 in)
Valve steam diameter (EXHAUST):	6.550 mm (0.2579 in)
Camshaft lobe height (INTAKE):	33.000 mm (1.2992 in)
Camshaft lobe height (EXHAUST):	32.600 mm (1.2835 in)
Camshaft journal diameter :	15.966-15.984 mm (0.6286-0.6293 in)

Tightening torque specs

Tightening torque specs
Connecting rod bolt	14 Nm; 1.4 kg·m; 10 ft·lb
Cylinder head bolt	35 Nm; 3.5 kg·m; 25 ft·lb
Flywheel nut	115 Nm; 11.5 kg·m; 83 ft·lb
Pivot adjusting nut	10 Nm; 1.0 kg·m; 7 ft·lb
Push rod guide pivot bolt	24 Nm; 2.4 kg·m; 17 ft·lb
Oil pan bolt	24 Nm; 2.4 kg·m; 17 ft·lb
Air cleaner body cap nut	9 Nm; 0.9 kg·m; 6.5 ft·lb
Muffler mounting nut	24 Nm; 2.4 kg·m; 17 ft·lb
Exhaust pipe mounting nut	24 Nm; 2.4 kg·m; 17 ft·lb
Oil drain plug	45 Nm; 4.5 kg·m; 34 ft·lb
Cylinder head cover bolt	9 Nm; 0.9 kg·m; 6.5 ft·lb
Fuel tank bolt	24 Nm; 2.4 kg·m; 17 ft·lb
Standard torque values
Bolt, nut (5 mm)	5.5 Nm; 0.55 kg·m; 4.0 ft·lb
Bolt, nut (6 mm)	10 Nm; 1.0 kg·m; 7 ft·lb
Bolt, nut (8 mm)	24 Nm; 2.4 kg·m; 17 ft·lb
Bolt, nut (10 mm)	37.5 Nm; 3.75 kg·m; 27 ft·lb
Bolt, nut (12 mm)	55 Nm; 5.5 kg·m; 40 ft·lb

Service Data

Engine
Maximum speed:	3400 ± 150 rpm
Idle speed:	1400 ± 150 rpm
Cylinder compression:	6.0-8.5 kg/cm2 (85-151 psi) at 600 rpm
Valve clearance
Intake valve clearance:	0.15 ± 0.02 mm (0.006 ± 0.001 in)
Exhaust valve clearance:	0.20 ± 0.02 mm (0.008 ± 0.001 in)
Oil system
Lubrication system:	Splash
Oil type:	Honda 4-stroke or an equivalent (SE or SF)
Recommended oil:	SAE 10W-40
Oil capacity:	1.1 L (1.16 US. qt, 0.97 Imp. qt.)
Fuel system
Type:	Horizontal type carburetor with butterfly valve
Main jet:	#88
Float height:	11.9-14.5 mm (0.47-0.57 in)
Pilot screw opening:	2-1/2 turns out
Ignition system
Type:	Transistorized magneto ignition
Ignition timing:	20° B.T.D.C. (Fixed)
Spark plug:	NGK: BPR5ES; NIPPONDENSO: W16EPR-U
Spark plug gap:	0.7-0.8 mm (0.0276-0.0315 in)
Ignition coil air gap	0.3-0.5 mm (0.0118-0.0197 in)

Applications

Manufacturer or Brand	Models
Tractors
Honda	H1011, H3011