Kohler M12

Kohler M12The Kohler M12 is a 476.4 cc (29.07 cu·in) single-cylinder air-cooled four-stroke internal combustion gasoline engine from the Magnum-series, manufactured by Kohler Co.

The Kohler M12 engine has an L-head (side valve) design and a horizontal PTO shaft. This engine is equipped with the Kohler-build side-draft carburetor with an adjustable jet and an electronic magneto ignition system. The M12 engine used a high-density paper air cleaner.

The cylinder bore is 85.85 mm (3.38 in) and the piston stroke is 82.6 mm (3.25 in). The compression ratio rating is 6.6:1.

The Kohler M12 engine produced 12.1 PS (8.9 KW; 12.0 HP) at 3,600 rpm of horsepower.

The breakdown of the engine code is as follows:

  • M – M-series
  • 12 – 12.0 HP horsepower
  • Suffix (engine is available with the following options):
    S – Electric starter;
    T – Retractable starter;
    ST – Electric and retractable starter;
    G – Tapered crankshaft (Generator applications);
    P – Threaded crankshaft (Pump applications);
    R – Reduction gear unit;
    EP – Generator;

General information

Engine Specifications
Type4-stroke, L-head, single cylinder
Displacement476.4 cm 3 (29.07 cu-in)
Max. horsepower12.1 PS (8.9 KW; 12.0 HP) at 3,600 rpm
Max. torque (crank PTO)
Fuel systemSide-draft carburetor
Cooling systemForced-air
Ignition systemElectronic magneto ignition system
Lubricating systemSplash type
Starting systemRecoil or electric starter
Fuel usedUnleaded gasoline (octane number 86 or higher)
Fuel tank capacity5.7 liters (1.5 US gal, 1.3 Imp. gal)
Weight58.5 kg (129 lbs)

Cylinder Block and Head

Cylinder block
Compression ratio:6.6:1
Bore x Stroke85.8 X 82.6 mm (3.38 x 3.25 in)
Sleeve internal diameter85.7123-85.7377 mm (3.3745-3.3755 in)
Piston skirt outer diameter85.4710-85.5472 mm (3.3650-3.3680 in)
Number of piston rings (compression / oil):2 / 1
Ring end gapTop0.254-0.508 mm (0.010-0.020 in)
Second0.254-0.508 mm (0.010-0.020 in)
Connecting rod small end ID22.2428-2.2505 mm (0.8757-0.8760 in)
Piston pin outer diameter22.2377-22.2351 mm (0.8752-0.8754 in)
Cylinder Head
Valve Arrangement:L-head (sidevalve)
Valve minimum lift – Zero lash:INTAKE8.07 mm (0.318 in)
EXHAUST8.07 mm (0.318 in)
Stem outer diameter (standard):INTAKE7.887-7.899 mm (0.3105-0.3110 in)
EXHAUST7.833-7.851 mm (0.3084-0.3091 in)

Tightening torque specs

Tightening torque specs
Cylinder head bolt34-41 Nm; 3.5-4.2 kg·m; 25-30 ft·lb
Spark plug25-30 Nm; 2.55-3.06 kg·m; 18-22 ft·lb

Service Information

Max speed3,600 rpm
Valve clearance
Intake valve clearance0.20-0.25 mm (0.0079-0.0098 in)
Exhaust valve clearance0.43-0.48 mm (0.0169-0.0189 in)
Oil system
Oil typeAPI SF or SG
Recommended oil Summer: SAE 30W
Winter: SAE 5W-20, 5W-30
Oil capacity1.9 L (2.0 US. qt, 1.67 Imp. qt.)
Ignition system
Spark plugChampion: RH10
Spark plug gap0.65 mm (0.0256 in)
Ignition module air gap0.30-0.40 mm (0.012-0.016 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.

Be the first to comment

Leave a Reply

Your email address will not be published.