The Honda GXV120 is a 118 cc (7.2 cu-in) single-cylinder air-cooled four-stroke internal combustion small gasoline engine with vertical shaft manufactured by Honda Motor Company for general-purpose applications, such as lawn mowers, commercial lawn and garden equipment, forestry equipment, construction and industrial equipment, agricultural equipment.
The Honda GXV120 engine has an OHV (overhead valve) design; horizontal type carburetor with butterfly valve; centrifugal mechanical governor; heavy-duty recoil or electric starter and transistorized magneto ignition system.
The cylinder bore is 60.0 mm (2.4 in) and the piston stroke is 42.0 mm (1.7 in), compression ratio rating is 8.0:1 or 8.7:1. The engine produced 4.0 HP (2.9 kW) of horsepower at 3,600 rpm and 8.0 Nm (0.82 kg·m, 5.92 ft·lb) of torque at 2,700 rpm.
General information
| Engine Specifications | |
| Model | GXV120 |
| Type | 4-stroke, OHV, single cylinder |
| Displacement | 118 cm 3 (7.2 cu-in) |
| Max. horsepower | 4.0 HP (2.9 kW) at 3,600 rpm |
| Max. torque (crank PTO) | 8.0 Nm (0.82 kg·m, 5.92 ft·lb) at 2,700 rpm |
| Carburetor | Horizontal type, butterfly valve |
| Cooling system | Forced-air |
| Ignition system | Transistorized magneto ignition |
| Lubricating system | Forced splash |
| Starting system | Recoil starter / Self starter |
| Stoping system | Ignition primary circuit ground |
| Fuel used | Unleaded gasoline (octane number 86 or higher) |
| Fuel tank capacity | 1.0 L (0.26 US qt) |
| Fuel consumption | 250 g/HPh |
| PTO shaft rotation | Counterclockwise (from PTO shaft side) |
Cylinder Block and Head
The Honda GXV120 motor has cast iron cylinder sleeve, ball bearing supported forged steel crankshaft. The piston has two compression rings and one oil ring. Precision camshaft design offers precise valve timing and optimal valve overlap for better fuel efficiency.
| Cylinder block | ||
| Compression ratio: |
8.7:1 for engine with S/N: 100001-1219523 8.0:1 for engine with S/N: from 1219524 |
|
| Bore x Stroke | 60 X 42 mm (2.4 x 1.7 in) | |
| Sleeve internal diameter | 60.000 mm (2.3622 in) | |
| Piston skirt outer diameter | 59.985 mm (2.3616 in) | |
| Number of piston rings (compression / oil): | 2 / 1 | |
| Ring side clearance | Top | 0.015-0.045 mm (0.0006-0.0018 in) |
| Second | 0.015-0.045 mm (0.0006-0.0018 in) | |
| Ring end gap | Top/Second | 0.20-0.40 mm (0.008-0.016 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 (0.5120 in) | |
| Connecting rod big end ID | 26.02 mm (1.024 in) | |
| Piston pin outer diameter | 13.0 mm (0.5118 in) | |
| Crankshaft crank pin outer diameter | 25.98 mm (1.023 in) | |
| Cylinder Head | ||
| Warpage (limit) | 0.10 mm (0.004 in) | |
| Valve Arrangement: | OHV | |
| Valves: | 2 | |
| Stem outer diameter (standard): | INTAKE | 5.480 mm (0.216 in) |
| EXHAUST | 5.440 mm (0.214 in) | |
| Valve spring free length: | 34.0 mm (1.339 in) | |
| Camshaft outer diameter: | 13.984 mm (0.5506 in) | |
| Cam height: | INTAKE | 27.70 mm (1.09 in) |
| EXHAUST | 27.75 mm (1.093 in) | |
Tightening torque specs
| Tightening torque specs | |
| Connecting rod lower cap | 12 Nm; 1.2 kg·m; 9 ft·lb |
| Cylinder head bolt | 24 Nm; 2.4 kg·m; 17 ft·lb |
| Flywheel nut | 75 Nm; 7.5 kg·m; 54 ft·lb |
| Pivot adjusting nut | 10 Nm; 1.0 kg·m; 7 ft·lb |
| Pivot bolt | 24 Nm; 2.4 kg·m; 17 ft·lb |
| Oil filter extension | 10 Nm; 1.0 kg·m; 7 ft·lb |
| Oil drain bolt | 18 Nm; 1.8 kg·m; 13 ft·lb |
| Oil pan | 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 Information
| Engine | |
| Maximum speed | 3,100 ± 100 rpm |
| Idle speed | 2,000 ± 150 rpm |
| Cylinder compression | 3.0-7.0 kg/cm2 (44-100 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 | |
| Oil type | Honda 4-stroke or an equivalent (SE or SF) |
| Recommended oil | SAE 10W-30 |
| Oil capacity | 0.6 L (0.63 US. qt, 0.53 Imp. qt.) |
| Carburetor | |
| Main jet | #65 |
| Float height | 12.2-15.2 mm (0.48-0.60 in) |
| Pilot screw opening | 3 turns out |
| Ignition system | |
| Ignition timing | 25° B.T.D.C. |
| Spark plug | NGK: BP5ES, BPR5ES NIPPONDENSO: W16EP-U, W16EPR-U |
| Spark plug gap | 0.7-0.8 mm (0.028-0.031 in) |
Author:
Buenos dias nesecito cotisacion de unos anillos y balbula de escape de motor hondagxv120 max.4ohp 3.0kw 118cc
Hi, I am looking for a part# for vale stem seals for this GXV120-118 engine.
Any help would be appreciated.
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