The Honda G65 is a 240 cc (14.6 cu-in) single-cylinder, air-cooled, four-stroke internal combustion small gasoline engine manufactured by Honda Motor Company since 1966 for general-purpose applications, such as: commercial lawn and garden equipment, tillers and cultivators, generators, construction and industrial equipment, agricultural equipment, small vehicles.
The Honda G65 engine has a slide valve (L-head) design and camshaft driven by a single row chain driven by the crankshaft. It has a recoil starter, horizontal carburetor with butterfly valve and high voltage ignition.
The G65 produced 6.8 PS (5.0 KW; 6.7 HP) at 4,000 rpm of max horsepower and 12.2 Nm (1.24 kg·m; 9.0 lbf·ft) at 3,000 rpm of peak torque. The dry weight of the Honda G65 engine was 27.6 kg (61.7 lbs). A 72 mm (2.8 in) cylinder bore and 59 mm (2.3 in) piston stroke give the engine a total of 240 cc (14.6 cu.in.) of displacement. The compression ratio is 6.1:1.
General information
Engine Specifications
Model
G65
Type
4-stroke, side valve type (L-head), single cylinder
Displacement
240 cm 3 (14.6 cu-in)
Max. horsepower
6.8 PS (5.0 KW; 6.7 HP) at 4,000 rpm
Max. torque
12.2 Nm (1.24 kg·m; 9.0 lbf·ft) at 3,000 rpm
Carburetor
Horizontal, butterfly valve
Cooling system
Forced-air
Ignition system
High voltage ignition
Lubricating system
Splash system
Starting system
Recoil starter
Stoping system
Ground switch
Fuel used
Unleaded gasoline (octane number 86 or higher)
Fuel tank capacity
6.9 liters (1.6 US gal., 1.5 Imp. gal.)
Fuel consumption
300 g/HPh (0.67 lb/HPh)
PTO shaft rotation
Counterclockwise (from PTO shaft side)
Cylinder Block and Head
Cylinder block
Compression ratio:
6.1:1
Bore x Stroke
72 X 59 mm (2.8 x 2.3 in)
Sleeve internal diameter
72.00 mm (2.835 in)
Piston skirt outer diameter
71.97 mm (2.833 in)
Piston ring side clearance (Top):
0.020 mm (0.0008 in)
Piston ring side clearance (Second):
0.010 mm (0.0004 in)
Piston ring side clearance (Oil):
0.010 mm (0.0004 in)
Ring width (Top):
2.480 mm (0.098 in)
Ring width (Second):
2.490 mm (0.098 in)
Ring width (Oil):
2.490 mm (0.098 in)
Piston pin outer diameter
19.000 mm (0.748 in)
Cylinder Head
Warpage (max)
0.2 mm (0.01 in)
Valve Arrangement:
Side valve type (L-head)
Valves:
2
Valve stem outer diameter (INTAKE):
6.970 mm (0.274 in)
Valve stem outer diameter (EXHAUST):
6.930 mm (0.273 in)
Valve guide inner diameter (INTAKE):
7.000 mm (0.276 in)
Valve guide inner diameter (EXHAUST):
7.000 mm (0.276 in)
Camshaft cam height (INTAKE):
35.18 mm (1.385 in)
Camshaft cam height (EXHAUST):
35.18 mm (1.385 in)
Maintenance data
Engine
Cylinder compression
4.0 kg/cm2 at 450-600 rpm
Tappet clearance
Intake valve
0.06-0.11 mm (0.0023-0.0043)
Exhaust valve
0.06-0.11 mm (0.0023-0.0043)
Oil system
Oil type
Honda 4-stroke or an equivalent (SG, SF)
Recommended oil
SAE 10W-30, 10W-40
Oil capacity
0.82 liters (1.7 US pt., 1.4 Imp. pt.)
Ignition system
Ignition timing
25 ° B.T.D.C (Fixed)
Spark plug
NGK: BR6HS, B6HS
Spark plug gap
0.6-0.7 mm (0.024-0.028 in)
Tightening torque specs
Tightening torque specs
Fuel tank (8 mm nut, bolt)
20-28 Nm; 2.0-2.8 kg·m; 14.5-20.2 ft·lb
Side cover (8 mm bolt)
20-25 Nm; 2.0-2.5 kg·m; 14.5-18.1 ft·lb
Cylinder Head (8 mm bolt)
20-25 Nm; 2.0-2.5 kg·m; 14.5-18.1 ft·lb
Cylinder (6 mm bolt)
8-12 Nm; 0.8-1.2 kg·m; 5.8-8.7 ft·lb
Cylinder (8 mm bolt)
20-28 Nm; 2.0-2.8 kg·m; 14.5-20.2 ft·lb
Camshaft center (6 mm bolt)
10-15 Nm; 1.0-1.5 kg·m; 7.2-10.8 ft·lb
Starter pulley (6 mm bolt)
8-12 Nm; 0.8-1.2 kg·m; 5.8-8.7 ft·lb
Flywheel (17 mm nut)
70-80 Nm; 7.0-8.0 kg·m; 50.6-57.9 ft·lb
Muffler (6 mm nut)
8-12 Nm; 0.8-1.2 kg·m; 5.8-8.7 ft·lb
Carburetor (6 mm nut)
8-12 Nm; 0.8-1.2 kg·m; 5.8-8.7 ft·lb
Author:Sergei WersAbout: Co-founder and CEO of a multi-brand auto repair shop (engine repair, chassis repair, body repair and painting) for over 15 years. I have been developing internet sites with technical specifications for more than seven years.
10 Comments
Bit more info please; bore dm., stnd. piston size etc with engine description.
How to fit new piston with rings if the con. rod big end is not a split one?
Can not get engine repair info on the internet. Can you suggest site with service manual?
The Honda G65 is a 240 cc (14.6 cu-in) single-cylinder, air-cooled, four-stroke internal combustion small gasoline engine manufactured by Honda Motor Company since 1966 for general-purpose applications, such as: commercial lawn and garden equipment, tillers and cultivators, generators, construction and industrial equipment, agricultural equipment, small vehicles.
Author:
Bit more info please; bore dm., stnd. piston size etc with engine description.
How to fit new piston with rings if the con. rod big end is not a split one?
Can not get engine repair info on the internet. Can you suggest site with service manual?
Unfortunately I also could not find the repair data for this engine
I found repair manuals on eBay for g65 honda engines. I bought one.
What is the link address for the g65 generator repair manual
I found g65 honda shop manuals on eBay cheap
What is the link address for the g65 manual
Looking for a carburettor kit for the G65 or a complete caburettor (shipping to Belgium-Europe requested). Thank you.Stefan
Bonjour je cherche un carburateur pour moteur g65 complet mais impossible de trouver
Bonjour,je recherche une pochette de joints de carburateur moteur honda G65.
Merci d’avance Michel
What about output shaft size ?