Kohler SV601

Kohler SV601The Kohler SV601 is a 597 cc, (36.4 cu·in) single-cylinder air-cooled four-stroke internal combustion gasoline engine from the Courage series, manufactured by Kohler Co.

The Kohler SV601 engine has an OHV (overhead valve) design, aluminum head and crankcase with cast iron cylinder liner, vertical PTO-shaft, and pressurized lubrication system. This engine is equipped with a carburetor with a fixed main jet and an electronic ignition system.

The cylinder bore is 94.0 mm (3.7 in) and the piston stroke is 86.0 mm (3.39 in). The compression ratio rating is 8.5:1. The SV601 engine produced 20.3 PS (14.9 KW; 20.0 HP) at 3,600 rpm of horsepower and 46.1 Nm (4.7 kg·m; 34.0 ft·lb) of torque.

The breakdown of the engine code is as follows:

  • S – Courage series
  • V – Vertical PTO shaft
  • 601 – Numerical designation

General information

Engine Specifications
Model Courage SV601
Type 4-stroke, OHV, single-cylinder
Displacement 597 cm 3 (36.4 cu-in)
Max. horsepower 20.3 PS (14.9 KW; 20.0 HP) at 3,600 rpm
Max. torque 46.1 Nm (4.7 kg·m; 34.0 ft·lb)
Fuel system Carburetor with a fixed main jet
Cooling system Forced-air
Ignition system Electronic ignition system
Lubricating system Pressurized lubrication
Starting system Electric starter
Fuel used Unleaded gasoline (octane number 86 or higher)
Fuel tank capacity

Cylinder Block and Head

Cylinder block
Compression ratio: 8.5:1
Bore x Stroke 94.0 X 86.0 mm (3.70 x 3.39 in)
Sleeve internal diameter 94.010-94.035 mm (3.7012-3.7022 in)
Number of piston rings (compression / oil): 2 / 1
Piston pin outer diameter 21.995-22.000 mm (0.8659-0.8661 in)
Main journal diameter Flywheel End Before S/N 3703200003: 44.913-44.935 mm (1.7682-1.7691 in)
After S/N 3703200013: 44.870-44.895 mm (1.7665-1.7675 in)
PTO End Before S/N 3703200003: 41.913-41.935 mm (1.6501-1.6510 in)
After S/N 3703200013: 41.855-41.880 mm (1.6478-1.6488 in)
Cylinder Head
Valve Arrangement: OHV
Valves: 2 (2 per cylinder)
Valve head diameter: INTAKE 37.375-37.625 mm (1.4715-1.4813 in)
EXHAUST 32.125-32.375 mm (1.2648-1.2746 in)
Stem outer diameter: INTAKE 5.982-6.000 mm (0.2355-0.2362 in)
EXHAUST 5.970-5.988 mm (0.235-0.2357 in)

Tightening torque specs

Tightening torque specs
Cylinder head bolt Step 1: 20.5 Nm (2.1 kg·m; 15.1 ft·lb)
Step 2: 41.0 Nm (4.2 kg·m; 30.3 ft·lb)
Flywheel M12: 88.0 Nm (9.0 kg·m; 65.0 ft·lb)
M10: 66.5 Nm (6.7 kg·m; 48.7 ft·lb)
Spark plug 27 Nm (2.75 kg·m; 20.0 ft·lb)

Service Information

Valve clearance
Intake valve clearance 0.127 mm (0.005 in)
Exhaust valve clearance 0.178 mm (0.007 in)
Oil system
Oil type API SJ or higher
Recommended oil SAE 10W-30
Oil capacity 1.5 L (1.59 US. qt, 1.32 Imp. qt.)
Ignition system
Spark plug Champion RC12YC
Spark plug gap 0.76 mm (0.030 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.

ATTENTION! Dear visitors, this site is not a trading platform, an official dealer or a spare parts supplier, so we do not have any price lists or spare parts catalogs. We are an information portal and provide the technical specifications of gasoline and diesel engines.

We try to use verified sources and official documentation, however, differences between sources or errors in entering information may occur. We do not provide advice on technical issues related to the engines operation or repair. We do not recommend using provided information for engines repairing engines or spare parts ordering, use only official service manuals and spare-parts catalogs.


  1. I have have had this mower for 20+ years and am extremely satisfied with it Done normal maintenance on it. use it to mow use a drag blade to keep my rock drive level. pulled several heavy items and it never has given me any problems. Have to do some rewiring now do to mice eating the plastic wrap around the wires. No problem.

  2. My 20 hp Kohler Courage manual states the oil capacity is 1.5 liters or about 50 oz. 39 oz will make the oil level at the full mark. Am I missing something, did it come with the wrong dipstick or is the manual wrong? Does anyone have an answer or idea why this is.

    • I’m no mechanic, but I don’t see an answer yet so I’m going to throw this out there. The way the oil filter mounts the oil filter retains oil, so 39oz may indeed fill the engine but what about oil that is retained by the oil filter. 39oz with the oil filter empty will result in a low oil level situation once the engine is ran and the oil filter fills with oil. Always fill a new oil filter before installing the new oil filter, then fill the engine to the correct level on the dipstick. Start the engine and allow oil to circulate. Turn the engine back from and allow the oil to settle, then check the oil level on the dipstick and top off as needed to bring the oil level to the proper level on the dipstick.

  3. Whole mowing my koler 20 hp lost power and will not take a load. Compression is 45 lbs I changed the fuel filter and cleaned out the carb bowl cleared out the jet with air, anybody had this problem?

Leave a Reply

Your email address will not be published.