The Yamaha MA175 is a 174 cc (10.6 cu-in) single-cylinder air-cooled 4-stroke internal combustion general-purpose gasoline engine with vertical shaft manufactured by Yamaha Motor Co., Ltd.
The Yamaha MA175 engine has a low-profile OHC (overhead cam) system with steel chain drive for optimized engine size and durability; hemispherical head with angled intake/exhaust valves; cast-iron cylinder line; float type carburetor; transistorized ignition system (T.C.I.).
The cylinder bore is 68.0 mm (2.67 in) and the piston stroke is 49.0 mm (1.89 in), compression ratio rating is 8.5:1. The engine produced 4.5 PS (3.4 kW) at 3,600 rpm of maximum horsepower. Maximum torque is 10.0 N·m (1.02 kg·m, 7.38 ft·lb) at 2,400 rpm.
General information
| Engine Specifications | |
| Model | MA175 |
| Type | 4-stroke, OHV, single cylinder |
| Displacement | 174 cm 3 (10.6 cu-in) |
| Max. horsepower | 4.5 PS (3.4 kW) at 3,600 rpm |
| Max. torque (crank PTO) | 10.0 N·m (1.02 kg·m, 7.38 ft·lb) at 2,400 rpm |
| Carburetor | Float type |
| Cooling system | Forced-air |
| Ignition system | Transitorized (T.C.I.) |
| Lubricating system | Mechanical splashing |
| Starting system | Recoil |
| Fuel used | Unleaded gasoline (octane number 86 or higher) |
| Fuel tank capacity | 1.2 L |
| PTO shaft rotation | Counterclockwise (from PTO shaft side) |
Dimensions and Weight
| Yamaha MA175 | |
| Length, mm (in) | 415 (16.3) |
| Width, mm (in) | 360 (14.2) |
| Height, mm (in) | 270 (10.6) |
| Dry weight, kg (lb) | 12.5 (27.6) |
Service Information
| Oil system | |
| Oil type | Yamalube 4-stroke or an equivalent (SE or SF) |
| Recommended oil | SAE 10W-30, 10W-40 |
| Oil capacity | 0.5 L (0.53 US. qt) |
| Ignition system | |
| Spark plug | NGK: BPR7HS |
| Spark plug gap | 0.7-0.8 mm (0.028-0.031 in) |
| Spark plug tightening torque | 20 N·m (2.0 kg·m, 14 ft·lb) |
Hello Sergei,
Thank you, a great site and very informative too. I am looking for the specification for the crankshaft end float or free movement in the crankcase of the crankshaft. I am unable to find anything although there must be a limit.
Unfortunately I don’t have access to the service manual for this engine, so I don’t have this information..