The Honda GX240 R2/RT2/T2/U2/UT2 is a 270 cc (16.5 cu·in) single-cylinder, air-cooled, four-stroke cycle, internal combustion small gasoline engine with horizontal shaft, manufactured by Honda Motor Company for general-purpose applications, such as: pressure washers, commercial lawn and garden equipment, tillers and cultivators, generators, construction or industrial equipment, agricultural equipment, small vehicles and water pumps.
This engine has an OHV design for increased efficiency and optimal power transfer; digital CDI (Capacitor Discharge Ignition) ignition system with variable timing; sophisticated air intake system; large capacity, multi-chamber exhaust system; heavy-duty recoil starter.
The GX240 R2/RT2/T2/U2/UT2 has few differences from GX240 UT1/T1/U1/K1: larger displacement 270 cc (GX240 K1 has 242 cc), larger piston diameter 77.0 mm (GX240 K1 has 73.0 mm), a compression ratio is increased to 8.5:1 (GX240 K1 – 8.2:1). This engine is equipped digital CDI ignition system (GX240 K1 has transistorized magneto ignition).
The second-generation Honda GX240 engine produces 8.01 PS (7.9 HP, 5.9 kW) at 3,600 rpm of max. output power and 18.3 Nm (1.86 kg·m, 13.4 lbf·ft) at 2,500 rpm of peak torque .
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 | GX240 R2/RT2/T2/U2/UT2 |
| Description code | R2 (GCBPK), RT2 (GCBJT), T2 (GCBKT), U2 (GCBPK), UT2 (GCBJT) |
| Type | 4-stroke, OVH, single cylinder, inclined by 25° |
| Displacement | 270 cm 3 (16.5 cu·in) |
| Max. horsepower | 8.01 PS (7.9 HP, 5.9 kW) at 3,600 rpm |
| Max. torque (crank PTO) | 18.3 Nm (1.86 kg·m, 13.4 lbf·ft) at 2,500 rpm |
| Carburetor | Horizontal type, butterfly valve |
| Cooling system | Forced-air |
| Ignition system | C.D.I.(Capacitor Discharge Ignition) type magneto ignition |
| Lubricating system | Forced splash |
| Starting system | Recoil, Recoil and Starter motor |
| Stoping system | Ignition exciter coil circuit open |
| Fuel used | Unleaded gasoline (octane number 86 or higher) |
| Fuel consumption | 2.2 Liters (0.58 US gal, 0.48 Imp gal) / h |
| PTO shaft rotation | Counterclockwise (from PTO shaft side) |
Dimensions and Weight
| GX240 UT2 | ||||||||
| 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) | 428 (16.9) | |||||||
| Height, mm (in) | 422 (16.6) | |||||||
| Dry weight, kg (lb) | 25.8 (56.9) | 25.8 (56.9) | 26.5 (58.4) | 30 (66.1) | 26.5 (58.4) | 25.8 (56.9) | 25.8 (56.9) | 25.8 (56.9) |
| Operating weight, kg (lb) |
30.5 (67.2) | 30.5 (67.2) | 31.5 (69.4) | 35 (77.2) | 31.5 (69.4) | 30.5 (67.2) | 30.5 (67.2) | 30.5 (67.2) |
| GX240 R2 | GX240 RT2 | GX240 T2 | GX240 U2 | |||
| Type E | Type V | Type H | Type P | Type Q | Type L | |
| Length, mm (in) | 360 (14.2) | 420 (16.5) | 425 (16.7) | 380 (15.0) | 380 (15.0) | 405 (15.9) |
| Width, mm (in) | 428 (16.9) | |||||
| Height, mm (in) | 303 (11.9) | 303 (11.9) | 410 (16.1) | 410 (16.1) | 410 (16.1) | 422 (16.6) |
| Dry weight, kg (lb) | 21.4 (47.2) | 21.4 (47.2) | 26.5 (58.4) | 25.8 (56.9) | 25.8 (56.9) | 26.5 (58.4) |
| Operating weight, kg (lb) |
26.1 (57.5) | 26.1 (57.5) | 31.5 (69.4) | 30.5 (67.2) | 30.5 (67.2) | 31.5 (69.4) |
Cylinder Block and Head
The Honda GX240 engine has a 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. The compression ratio rating is 8.5:1.
| Cylinder block | ||
| Compression ratio: | 8.5:1 | |
| Bore x Stroke | 77.0 X 58.0 mm (3.0 x 2.3 in) | |
| Sleeve internal diameter | 77.000-77.017 mm (3.0315-3.0322 in) | |
| Piston skirt outer diameter | 76.975-76.985 mm (3.0305-3.0309 in) | |
| Number of piston rings (compression / oil): | 2 / 1 | |
| Piston ring side clearance (Top): | 0.030-0.060 mm (0.0012-0.0024 in) | |
| Piston ring side clearance (Second): | 0.030-0.060 mm (0.0012-0.0024 in) | |
| Piston ring side clearance (Oil): | 0.030-0.060 mm (0.0012-0.0024 in) | |
| Piston ring end gap (Top): | 0.200-0.350 mm (0.0079-0.0138 in) | |
| Piston ring end gap (Second): | 0.350-0.500 mm (0.0138-0.0197 in) | |
| Piston ring end gap (Oil – side rail): | 0.200-0.700 mm (0.010-0.030 in) | |
| Ring width (Top): | 1.160-1.175 mm (0.0457-0.0463 in) | |
| Ring width (Second): | 1.160-1.175 mm (0.0457-0.0463 in) | |
| Piston pin outer diameter | 17.994-18.000 mm (0.7084-0.7087 in) | |
| Piston pin bore inner diameter | 18.002-18.008 mm (0.7087-0.7090 in) | |
| Conrod small end inner diameter | 18.005-18.020 mm (0.7089-0.7094 in) | |
| Conrod big end inner diameter | 33.025-33.039 mm (1.3002-1.3007 in) | |
| Crankshaft outer diameter | 32.975-32.985 mm (1.2982-1.2986 in) | |
| Cylinder Head | ||
| Warpage (limit) | 0.10 mm (0.004 in) | |
| Valve Arrangement: | OHV | |
| Valves: | 2 | |
| Valve stem outer diameter (INTAKE): | 6.575-6.590 mm (0.2589-0.2594 in) | |
| Valve stem outer diameter (EXHAUST): | 6.535-6.550 mm (0.2573-0.2579 in) | |
| Valve guide inner diameter (INTAKE): | 6.600-6.615 mm (0.2598-0.2604 in) | |
| Valve guide inner diameter (EXHAUST): | 6.600-6.615 mm (0.2598-0.2604 in) | |
| Guide-to-stem clearance (INTAKE): | 0.010-0.040 mm (0.0004-0.0016 in) | |
| Guide-to-stem clearance (EXHAUST): | 0.050-0.080 mm (0.002-0.0031 in) | |
| Camshaft cam height (INTAKE): | 31.945-32.145 mm (1.2577-1.2655 in) | |
| Camshaft cam height (EXHAUST): | 31.666-31.866 mm (1.2467-1.2546 in) | |
| Valve seat width: | 1.0-1.2 mm (0.040-0.050 in) | |
| Valve spring free length: | 39.0 mm (1.54 in) | |
| Camshaft outer diameter: | 15.966-15.984 mm (0.6286-0.6293 in) | |
Maintenance data
| Engine | |
| Maximum speed | 3,850 ± 150 rpm |
| Idle speed | 1,400 ± 150 rpm |
| Cylinder compression | 6.0-8.5 kg/cm2 (85-121 psi, 0.59 – 0.83 MPa) at 600 rpm |
| Valve clearance | |
| Intake valve | 0.15 ± 0.02 mm (0.006 ± 0.001 in) |
| Exhaust valve | 0.20 ± 0.02 mm (0.008 ± 0.001 in) |
| Carburetor | |
| Main jet | BE70R A: #85 BE71F A: #85 |
| Float height | 13.2 mm (0.52 in) |
| Pilot screw opening | 1 turns out |
| Oil system | |
| Oil type | Honda 4-stroke or an equivalent (SE or later) |
| Recommended oil | SAE 10W-30 |
| Oil capacity | 1.1 liters (1.16 US.qts, 0.97 Imp. qts) |
| Ignition system | |
| Ignition timing | B.T.D.C. 10° / 1,400 rpm |
| Spark plug | NGK: BPR6ES DENSO: W20EPR-U |
| Spark plug gap | 0.7-0.8 mm (0.028-0.031 in) |
| Ignition coil air gap | 0.2-0.6 mm (0.01-0.02 in) |
| Starter motor | |
| Brush length |
7.0 mm (0.28 in) Limit: 3.5 mm (0.14 in) |
| Mica depth |
1.0 mm (0.04 in) Limit: 0.2 (0.01) |
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 |
Author:
what is the OEM # for the muffler for this engine?