Kohler XT-8

The Kohler XT-8 is a 173 cc (10.6 cu·in) natural aspirated single-cylinder four-stroke air-cooled internal combustion small gasoline engine from the Courage XT-series with a vertical shaft, manufactured by Kohler Co for general-purpose applications, such as log splitter, pressure washer, tiller, walk-behind mower, yard vacuum.

The cylinder bore and the piston stroke are 70.0 mm (2.75 in) and 45.0 mm (1.80 in), respectively. Compression ratio rating is 8.5:1.

The Kohler XT8 engine produces 5.3 PS (3.9 KW; 5.2 HP) at 3,600 rpm of maximum horsepower 10.8 Nm (1.1 kg·m; 8.0 ft·lb) at 2,600 rpm of peak torque.

The Kohler XT-8 features:

• OHV design
• Aluminum cylinder block
• Cast iron cylinder liners
• Dependable electronic magneto ignition system
• Flywheel ball bearing
• Carburetor with fixed main jet
• Mechanical centrifugal governor
• Spalsh type lubrication
• Forced air cooling system
• Recoil starter

General information

Engine Specifications
Engine model	XT-8
Engine type	4-stroke, OHV, single-cylinder
Displacement	173 cm 3 (10.6 cu-in)
Max. horsepower	5.3 PS (3.9 KW; 5.2 HP) at 3,600 rpm
Max. torque	10.8 Nm (1.1 kg·m; 8.0 ft·lb) at 2,600 rpm
Cooling system	Forced air
Air cleaner	Replaceable, paper element
Lubricating system	Splash type
Ignition system	Dependable electronic magneto
Fuel system	Carburetor with fixed main jet
Fuel used	Unleaded gasoline (octane number 86 or higher)
Fuel tank capacity	1.4 liters (1.48 US.qts, 1.23 Imp. qts)
Starting system	Recoil starter
Governor	Mechanical centrifugal governor
PTO shaft rotation	Counterclockwise (from PTO shaft side)
Dimensions (L x W X H)	434 x 353 x 279 mm (17.1 x 13.9 x 11.0 in)
Dry weight	13.8 kg (30.5 lbs)

Cylinder Block and Head

Cylinder block
Compression ratio:	8.5:1
Cylinder bore:	70.0 mm (2.75 in)
Piston stroke:	45.0 mm (1.80 in)
Cylinder internal diameter (standard):	70.000-70.020 mm (2.7550-2.7560 in)
Number of piston rings (compression / oil):	2/1
Piston pin diameter:	17.990-17.996 mm (0.7082-0.7085 in)
Thrust face outer diameter (standard):	69.960-69.980 mm (2.7543-2.7551 in)
Ring-to-groove side clearance (Top):	Before s/n 40244XXXXX: 0.020-0.060 mm (0.0007-0.0023 in) After s/n 40243XXXXX: 0.010-0.020 mm (0.0004-0.0008 in)
Ring-to-groove side clearance (Second):	Before s/n 40244XXXXX: 0.020-0.060 mm (0.0007-0.0023 in) After s/n 40243XXXXX: 0.010-0.020 mm (0.0004-0.0008 in)
Ring end gap (Top):	Before s/n 40244XXXXX: 0.250-0.400 mm (0.0098-0.0157 in) After s/n 40243XXXXX: 0.100-0.250 mm (0.0039-0.0098 in)
Ring end gap (Second):	Before s/n 40244XXXXX: 0.250-0.400 mm (0.0098-0.0157 in) After s/n 40243XXXXX: 0.300-0.500 mm (0.0118-0.0197 in)
Number of main bearings:	2
Crankshaft main journal diameter:	Flywheel: 24.975-24.989 mm (0.9832-0.9838 in) PTO: Early: 25.370-25.385 mm (0.9988-0.9994 in) Later: 26.950-26.970 mm (1.0610-1.0620 in)
Crankpin journal diameter:	29.985-29.995 mm (1.1805-1.1809 in)
Cylinder head
Valve arrangement:	OHV, gear driven
Valves:	2 (4 valves in total)
Valve head diameter (INTAKE):	25.875-26.125 mm (1.0187-1.0285 in)
Valve head diameter (EXHAUST):	23.875-24.125 mm (0.9399-0.9498 in)
Valve seat angle (INTAKE):	44.5°
Valve seat angle (EXHAUST):	44.5°
Valve seat angle (INTAKE):	45°
Valve seat angle (EXHAUST):	45°
Valve steam diameter (INTAKE):	5.465-5.480 mm (0.2152-0.2157 in)
Valve steam diameter (EXHAUST):	5.465-5.480 mm (0.2152-0.2157 in)

Tightening torque specs

Tightening torque specs
Connecting rod	12.5 Nm (1.3 kgf·m; 9.2 ft·lb)
Cylinder head (torque in 2 increments)	Step 1: 14.0 Nm (1.4 kgf·m; 10.3 ft·lb) Step 2: 27.8 Nm (2.8 kgf·m; 20.5 ft·lb)
Rocker arm stud	13.6 Nm (1.4 kgf·m; 10.0 ft·lb)
Rocker arm pivot jam nut	9.5 Nm (1.0 kgf·m; 7.0 ft·lb)
Flywheel	51.5 Nm (5.3 kgf·m; 38 ft·lb)
Muffler	Exhaust stud: 5.0 Nm (0.5 kgf·m; 3.7 ft·lb) Exhaust nut: 9.5 Nm (1.0 kgf·m; 7.0 ft·lb)
Spark plug	27.0 Nm (2.75 kg·m; 20.0 ft·lb)
Oil drain plug	13.6 Nm (1.4 kgf·m; 10.0 ft·lb)

Service Data

Valve clearance
Intake/Exhaust:	0.0762-0.1270 mm (0.0030-0.0050 in)
Oil system
Lubrication system:	Splash type
Oil type:	API SJ or higher
Recommended oil:	SAE 10W-30
Oil capacity:	0.6 liters (0.63 US.qts, 0.53 Imp. qts)
Fuel system
Type:	Carburetor with fixed main jet
Fuel filter:	In-line fuel filter
Ignition system
Type:	Dependable electronic magneto
Spark plug:	Kohler 141-32-11-S
Spark plug gap:	0.76 mm (0.030 in)
Ignition coil air gap	0.254 mm (0.010 in)