Honda GCV135

The Honda GCV135 is a small (135 cc) single-cylinder air-cooled 4-stroke internal combustion gasoline engine with vertical shaft, manufactured by Honda Motor Company since 1997 for general-purpose applications such as: pressure washers, lawn mowers, agricultural equipment, forestry equipment.

This engine has a single-cylinder, compact combustion chamber, tough resin overhead cam for durability and quietness and uniblock construction reduce fuel consumption. The Honda GCV135 engine has transistorized magneto ignition, horizontal type carburetor, and recoil starter.

A 64 mm (2.5 in) cylinder bore and 42 mm (1.7 in) piston stroke give the engine a total of 135 cc (8.2 cu-in) of displacement. Compression ratio rating is 8.5:1. It produces 3.3 kW (4.5 HP) at 3,600 rpm and 9.7 N·m (0.99 kg·m, 7.2 ft·lb) of torque at 2,500 rpm.

General information

Engine Specifications
Model	GCV135 (vertical shaft)
Type	4-stroke, OHC, single cylinder
Displacement	135 cm 3 (8.2 cu-in)
Max. horsepower	4.5 HP (3.3 kW) at 3,600 rpm
Max. torque (crank PTO)	9.7 N·m (0.99 kg·m, 7.2 ft·lb) at 2,500 rpm
Carburetor	Horizontal type, butterfly valve
Cooling system	Forced-air
Ignition system	Transistorized magneto ignition
Lubricating system	Splash
Starting system	Recoil starter
Stoping system	Ignition primary circuit ground
Fuel used	Unleaded gasoline (octane number 86 or higher)
Fuel tank capacity	0.9 l (0.24 US. Gal, 0.20 Imp. Gal.)
Fuel consumption	230 g/HPh
PTO shaft rotation	Counterclockwise (from PTO shaft side)

Dimensions and Weight

	N1	N2	N3	N4
Length, mm (in)	351 (13.8)
Width, mm (in)	331 (13.0)
Height, mm (in)	353 (13.9)	340 (13.4)	358 (14.1)	340 (13.4)
Dry weight, kg (lb)	9.5 (20.9)
Operating weight, kg (lb)	10.8 (23.8)

Cylinder Block and Head

Cylinder block
Compression ratio:		8.5:1
Bore x Stroke		64 mm X 42 mm (2.5 x 1.7 in)
Sleeve internal diameter		64.00 mm (2.52 in)
Piston skirt outer diameter		63.969 mm (2.5185 in)
Number of piston rings (compression / oil):		2 / 1
Ring side clearance	Top/second/oil	0.015-0.045 mm (0.0006-0.0018 in)
Ring end gap	Top	0.20-0.35 mm (0.008-0.014 in)
	Second	0.30-0.45 mm (0.012-0.018 in)
	Oil	0.15-0.35 mm (0.006-0.014 in)
Ring width	Top/second	1.5 mm (0.06 in)
	Oil	2.5 mm (0.10 in)
Connecting rod small end ID		13.005 mm (0.512 in)
Connecting rod big end ID		26.02 mm (1.024 in)
Crankpin outer diameter		25.98 mm (1.023 in)
Main journal outer diameter	PTO side	27.993 mm (1.1021 in)
	Flywheel side	25.393 mm (0.9997 in)
Cylinder Head
Warpage (limit)		0.10 mm (0.004 in)
Valve Arrangement:		OHC
Valves:		2
Stem outer diameter (standard):	INTAKE	5.480 mm (0.216 in)
	EXHAUST	5.44 mm (0.214 in)
Guide internal diameter	INTAKE / EXHAUST	5.5 mm (0.2165 in)
Spring free length		34.0 mm (1.34 in)

Tightening torque specs

Tightening torque specs
Air cleaner case bolt	10 Nm; 1.0 kg·m; 7 ft·lb
Connecting rod bolt	12 Nm; 1.2 kg·m; 8.6 ft·lb
Valve adjusting lock nut	8 Nm; 0.8 kg·m; 5.8 ft·lb
Cylinder head cover bolt	12 Nm; 1.2 kg·m; 8.6 ft·lb
Oil drain plug bolt	24 Nm; 2.4 kg·m; 17 ft·lb
Flywheel nut	52 Nm; 5.3 kg·m; 38 ft·lb
Governor arm nut	10 Nm; 1.0 kg·m; 7 ft·lb
Muffler bolt	12 Nm; 1.2 kg·m; 8.6 ft·lb
Recoil starter nut	8.5 Nm; 0.85 kg·m; 6.1 ft·lb
Fan cover stud bolt	12 Nm; 1.2 kg·m; 8.6 ft·lb
Spark plug	20 Nm; 2.0 kg·m; 14 ft·lb
Others
5 mm bolts, nuts	5.5 Nm; 0.55 kg·m; 4.0 ft·lb
6 mm bolts, nuts	10 Nm; 1.0 kg·m; 7 ft·lb
8 mm bolts, nuts	24 Nm; 2.4 kg·m; 17 ft·lb
10 mm bolts, nuts	37 Nm; 3.7 kg·m; 27 ft·lb
12 mm bolts, nuts	55 Nm; 5.5 kg·m; 39.5 ft·lb

Service Information

Engine
Maximum speed	3,000 ± 150 rpm
Idle speed	1,700 ± 150 rpm
Cylinder compression	5.0 kg/cm2 (71 psi) at 600 rpm
Valve clearance
Intake valve	0.15 ± 0.04 (0.006 ± 0.002)
Exhaust valve	0.20 ± 0.04 (0.008 ± 0.002)
Oil system
Oil type	Honda 4-stroke or an equivalent (SE or SF)
Recommended oil	SAE 10W-30
Oil capacity	0.55 l (0.58 US. qt, 0.48 Imp. qt.)
Ignition system
Ignition timing	20° B.T.D.C.
Spark plug	NGK: BPR6ES
Spark plug gap	0.7-0.8 mm (0.028-0.031 in)
Spark plug tightening torque	20 Nm; 2.0 kg·m; 14 ft·lb
Primary ignition coil resistance	1.0-1.2 kΩ
Secondary ignition coil resistance	10.6-12.8 kΩ
Ignition coil air gap	0.2-0.6 mm (0.008-0.024 in)
Carburetor
Main jet	#60
Float height	9.2 mm (0.36 in)
Pilot screw opening	1-5/8 turns out