Rato RV140

Rato RV140The Rato RV140 is a 140 cc (9.15 cu-in) single-cylinder air-cooled 4-stroke internal combustion general-purpose gasoline engine with vertical shaft, manufactured by Chongqing RATO Holding (Group) CO., LTD for lawn mowers and tillers.

The Rato RV140 engine has a single-cylinder with a vertical shaft; an overhead valve (OHV) design; flat suction valve carburetor; dual element air filtration system; capacitance discharge type ignition system; centrifugal mechanical governor system and recoil starter.

The Rato RV140 motor has a 65.0 mm (2.56 in) cylinder bore and 42.0 mm (1.65 in) piston stroke with a compression ratio of 8.5:1. It produced 4.0 HP at 3,600 rpm of horsepower and 6.3 N·m (0.64 kg·m, 5.75 ft·lb) at 2,500 rpm of torque.

General information

Engine Specifications
Type4-stroke, OHV, single cylinder
Displacement140 cm 3 (8.54 cu-in)
Max. horsepower4.0 HP at 3,600 rpm
Max. torque (crank PTO)6.3 N·m (0.64 kg·m, 4.6 ft·lb) at 2,500 rpm
CarburetorFlat suction valve carburetor
Cooling systemForced-air
Ignition systemCapacitance Discharge Ignition (CDI)
Lubricating systemSplash
Starting systemRecoil starter
Stoping systemIgnition primary circuit ground
Fuel usedUnleaded gasoline (octane number 86 or higher)
Fuel tank capacity1.0 L
PTO shaft rotationCounterclockwise (from PTO shaft side)

Service Information

Valve clearance (Cold)
Intake valve (COLD)0.15 mm (0.006 in)
Exhaust valve (COLD)0.20 mm (0.008 in)
Oil system
Oil type4-stroke or an equivalent (SJ)
Recommended oilSAE 10W-30, 15W-40
Oil capacity0.45 L
Ignition system
Spark plugNGK: BPR6ES
Spark plug gap0.7-0.8 mm (0.028-0.031 in)
Author: Sergei Wers
About: Co-founder and CEO of a multi-brand auto repair shop (engine repair, chassis repair, body repair and painting) for over 15 years. I have been developing internet sites with technical specifications for more than seven years.

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    • Valve clearance is:
      Intake: 0.15 mm (0.006 in)
      Exhaust: 0.20 mm (0.008 in)
      The intake is the upper valve and the exhaust lower

  1. Hello. I hope you can help me find two parts needed for a Rato RV 140 engine (OHV 550, 140cc engine). I’m seeking a throttle valve returning spring and a governor spring. Unfortunately, I don’t have part numbers for either. I hope someone can provide the part number of springs that are similar on other Rato engines or another brand like Husqvarna. Thanks so much for any advice you can provide.

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