Rato R180

The Rato R180 is a 179 cc (10.9 cu-in) single-cylinder air-cooled 4-stroke internal combustion general-purpose gasoline engine with horizontal shaft manufactured by Chongqing RATO Holding (Group) CO., LTD.

The Rato R180 engine has an OHV design; flat suction valve carburetor; recoil starter or electric starter, transistorized magneto ignition (TCI) system and centrifugal mechanical governor system.

A 65.0 mm (2.56 in) cylinder bore and 54.0 mm (2.13 in) piston stroke give the Rato R180 motor a total of 179 cc of displacement. Compression ratio rating is 8.5±0.3:1. It produced 6.0 HP of horsepower at 3,600 rpm and 9.0 N·m (0.92 kg·m, 6.64 ft·lb) of torque at 2,500 rpm.

General information

Engine Specifications
Model	R180
Type	4-stroke, OHV, single cylinder
Displacement	179 cm 3 (10.9 cu-in)
Max. horsepower	6.0 HP at 3,600 rpm
Max. torque (crank PTO)	9.0 N·m (0.92 kg·m, 6.64 ft·lb) at 2,500 rpm
Carburetor	Flat suction valve carburetor
Cooling system	Forced-air
Ignition system	Transistorized magneto ignition (TCI)
Lubricating system	Splash
Starting system	Recoil / electric starter
Stoping system	Ignition primary circuit ground
Fuel used	Unleaded gasoline (octane number 86 or higher)
PTO shaft rotation	Counterclockwise (from PTO shaft side)

Cylinder Block and Head

The Rato R180 engine has cast-iron cylinder liner, dual ball bearings and steel forged and hardened crankshaft.

Cylinder block
Compression ratio:		8.5:1
Bore x Stroke		65 X 54 mm (2.56 x 2.13 in)
Cylinder Head
Warpage (limit)		0.10 mm (0.004 in)
Valve Arrangement:		OHV
Valves:		2

Service Information

Engine
Maximum speed	3800 ± 200 rpm
Idle speed	1550 ± 150 rpm
Cylinder compression	12.0 kg/cm2 at 1400 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	4-stroke or an equivalent (SJ)
Recommended oil	SAE 10W-30, 15W-40
Oil capacity	0.6 L
Ignition system
Spark plug	NGK:BPR6ES
Spark plug gap	0.7-0.8 mm (0.028-0.031 in)