The Honda GX270 K1/T1/UT1 is a 270 cc (16.5 cu-in) single-cylinder (inclined by 25 °), air-cooled, four-stroke cycle, internal combustion small gasoline engine manufactured by Honda Motor Company.
This engine has an OHV design with two valves; sophisticated air intake system; large capacity, multi-chamber exhaust system; heavy-duty recoil starter.
The Honda GX270 K1/T1/UT1 engine produces 9.12 PS (9.0 HP, 6.7 kW) at 3,600 rpm of max output power and 19.5 Nm (2.0 kg·m; 14.4 lbf·ft) at 2,500 rpm of peak torque. With 1/2 reduction it produces 39.0 Nm (3.9 kg·m, 28.0 lbf·ft) of torque at 1,250 rpm, with 1/6 reduction up to 117.0 Nm (11.7 kg·m, 85.0 lbf·ft) at 2,000 rpm.
From spring 2010 onwards, Honda producing the updated version of GX270 engines. This engine meets the most stringent exhaust gas emission regulation, EPA Phase III.
PTO Shaft Options
- E type – tapered shaft;
- H type – 1/6 reduction type PTO;
- L type – 1/2 reduction type PTO;
- P type – threaded type (SAE);
- Q type – straight shaft;
- R type – 1/2 reduction type PTO with centrifugal clutch;
- V type – tapered shaft;
General information
| Engine Specifications | |
| Model | GX270 |
| Type | 4-stroke, OHV, single cylinder, inclined by 25° |
| Displacement | 270 cm 3 (16.5 cu-in) |
| Max. horsepower | 9.1 PS (6.7 KW; 9.0 HP) at 3,600 rpm |
| Max. torque (crank PTO) | 19.5 Nm (2.0 kg·m; 14.4 lbf·ft) at 2,500 rpm |
| Carburetor | Horizontal type, butterfly valve |
| Cooling system | Forced-air |
| Ignition system | Transistorized magneto ignition |
| Lubricating system | Splash type |
| Starting system | Recoil or electric starter |
| Stoping system | Ignition primary circuit ground |
| Fuel used | Unleaded gasoline (octane number 86 or higher) |
| Fuel tank capacity | 6.0 liters (6.3 US.qts, 5.3 Imp. qts) |
| Fuel consumption | 313 g/kWh (230 g/HPh, 0.51 lb/HPh) |
| PTO shaft rotation | Counterclockwise (from PTO shaft side) |
Dimensions and Weight
| Type S | Type Q | Type L | Type R | Type H | Type W | Type P | Type V | |
| Length, mm (in) | 355 (14.0) | 380 (15.0) | 405 (15.9) | 440 (17.3) | 425 (16.7) | 370 (14.6) | 380 (15.0) | 400 (15.7) |
| Width, mm (in) | 430 (16.9) | |||||||
| Height, mm (in) | 410 (16.1) | |||||||
| Dry weight, kg (lb) | 25 (55.1) | 25 (55.1) | 26.5 (58.4) | 30 (66.1) | 26.5 (58.4) | 25 (55.1) | 25 (55.1) | 25 (55.1) |
| Operating weight, kg (lb) |
30 (66.1) | 30 (66.1) | 31.5 (69.4) | 35 (77.2) | 31.5 (69.4) | 30 (66.1) | 30 (66.1) | 30 (66.1) |
Cylinder Block and Head
The Honda GX270 has cast iron cylinder sleeve, ball bearing supported crankshaft, improved piston design, heavy-duty balancer shaft. 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: | 8.2 | |
| Bore x Stroke | 77.0 X 58.0 mm (3.0 x 2.3 in) | |
| Sleeve internal diameter | 77.000 mm (3.031 in) | |
| Piston skirt outer diameter | 76.985 mm (3.0309 in) | |
| Number of piston rings (compression / oil): | 2 / 1 | |
| Piston ring side clearance (Top): | 0.015-0.045 mm (0.0006-0.0018 in) | |
| Piston ring side clearance (Second): | 0.015-0.045 mm (0.0006-0.0018 in) | |
| Piston ring side clearance (Oil): | 0.015-0.045 mm (0.0006-0.0018 in) | |
| Piston ring end gap (Top): | 0.200-0.400 mm (0.01-0.02 in) | |
| Piston ring end gap (Second): | 0.200-0.400 mm (0.01-0.02 in) | |
| Piston ring end gap (Oil): | 0.200-0.700 m (0.01-0.03 in) | |
| Ring width (Top): | 2.0 mm (0.08 in) | |
| Ring width (Second): | 2.0 mm (0.08 in) | |
| Crankshaft outer diameter | 32.985 mm (1.2986 in) | |
| Cylinder Head | ||
| Warpage (limit) | 0.10 mm (0.004 in) | |
| Valve Arrangement: | Overhead valve (OHV) | |
| Valves: | 2 | |
| Valve stem outer diameter (INTAKE): | 6.590 mm (0.259 in) | |
| Valve stem outer diameter (EXHAUST): | 6.550 mm (0.258 in) | |
| Camshaft cam height (INTAKE): | 31.520-31.920 mm (1.241-1.257 in) | |
| Camshaft cam height (EXHAUST): | 31.560-31.960 mm (1.243-1.258 in) | |
| Camshaft outer diameter: | 15.984 mm (0.6293 in) | |
Maintenance data
| Engine | |
| Maximum speed | 3,850 ± 150 rpm |
| Idle speed | 1,400 ± 150 rpm |
| Cylinder compression | 6.0-8.5 kg/cm2 (85-151 psi) at 600 rpm |
| Valve clearance | |
| Intake valve | 0.15 ± 0.02 (0.006 ± 0.001) |
| Exhaust valve | 0.20 ± 0.02 (0.008 ± 0.001) |
| Carburetor | |
| Main jet | Externally vented carburetor bowl: #88 Internally vented carburetor bowl: #95 |
| Float height | 13.2 mm (0.52 in) |
| Pilot screw opening | 2 |
| Oil system | |
| Oil type | Honda 4-stroke or an equivalent (SG.SF/CC.CD) |
| Recommended oil | SAE 10W-30 |
| Oil capacity | 1.1 liters (1.16 US.qts, 0.97 Imp. qts) |
| Ignition system | |
| Ignition timing | 20° B.T.D.C (Fixed) |
| Spark plug | NGK: BP6ES, BPR6ES NIPPONDENSO: W20EP-U, W20EPR-U |
| Spark plug gap | 0.7-0.8 mm (0.028-0.031 in) |
| Spark plug cap | 7.5-12.5 kΩ |
| Primary ignition coil resistance | 0.8-1.0 Ω |
| Secondary ignition coil resistance | 5.9-7.1 kΩ |
| Ignition coil air gap | 0.4 ± 0.2 (0.016 ± 0.008) |
| Starter motor | |
| Brush length | 7.2 mm (0.28 in) limit: 3.5 mm (0.14 in) |
| Mica depth | 1.0 mm (0.04 in) limit: 0.2 mm (0.01 in) |
Tightening torque specs
| Tightening torque specs | |
| Connecting rod bolt (M8x1.25 Special) | 14 Nm; 1.4 kg·m; 10 ft·lb |
| Cylinder head bolt (M10x1.25) | 35 Nm; 3.5 kg·m; 25 ft·lb |
| Flywheel nut (M16x1.5 Special) | 115 Nm; 11.5 kg·m; 83 ft·lb |
| Rocker arm pivot lock nut (M6x0.5) | 10 Nm; 1.0 kg·m; 7 ft·lb |
| Rocker arm pivot bolt (M8x1.25 Special) | 24 Nm; 2.4 kg·m; 17 ft·lb |
| Crankcase cover bolt (M8x1.25) | 24 Nm; 2.4 kg·m; 17 ft·lb |
| Oil level switch joint nut (M10x1.25) | 10 Nm; 1.0 kg·m; 7 ft·lb |
| Fuel filter joint nut (M10x1.25) | 2 Nm; 0.2 kg·m; 1.4 ft·lb |
| Muffler mounting nut (M8x1.25) | 24 Nm; 2.4 kg·m; 17 ft·lb |
| Air cleaner wing nut (M6x1.0) | 9 Nm; 0.9 kg·m; 6.5 ft·lb |
| Oil drain bolt (M12x1.5) | 23 Nm; 2.3 kg·m; 17 ft·lb |
| Fuel tank bolt (M8x1.25) | 24 Nm; 2.4 kg·m; 17 ft·lb |
| Air cleaner mounting nut (M6x1.0) | 10 Nm; 1.0 kg·m; 7 ft·lb |
| Fuel strainer cup (M24x1.0) | 4 Nm; 0.4 kg·m; 2.9 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 |
Engine applications
- Pressure washers
- Commercial lawn and garden equipment
- Tillers / cultivators
- Generators
- Construction / industrial equipment
- Agricultural equipment
- Small vehicles
- Water pumps
Author:
The oil capacity is 1.16 quarts not gallons.