Kohler ECH630

Kohler ECH630The Kohler ECH630 is a 694 cc (42.4 cu·in) natural aspirated V-twin four-stroke air-cooled internal combustion small gasoline engine from the Command PRO EFI series with a horizontal shaft, manufactured by Kohler Co for general-purpose applications.

A 80.0 mm (3.15 in) cylinder bore and 69.0 mm (2.72 in) piston stroke give the ECH630 engine a total of 694 cc of displacement. The compression ratio rating is 8.7:1.

The ECH630 engine produces 19.3 PS (14.2 KW; 19.0 HP) at 3,600 rpm of maximum horsepower and 46.4 Nm (4.73 kg·m; 34.24 ft·lb) at 2,200 rpm of peak torque.

The Kohler ECH630 features:

  • OHV (overhead valve) design
  • Hydraulic valve lifters
  • Aluminum cylinder block
  • Cast iron cylinder liners
  • Hardened crank journals
  • PTO thrust bearing
  • Electronic ignition system
  • Electronic fuel injection system (EFI)
  • Full pressure lubrication system
  • Oil cooler
  • Spin-on, full-flow oil filter
  • Forced air cooling system
  • Solenoid shift starter
  • 20 amp charging, regulated

General information

Engine Specifications
Engine model Command PRO EFI ECH630
Engine type 4-stroke, OHV, V-twin
Displacement 694 cm3, (42.4 cu·in)
Max. horsepower 19.3 PS (14.2 KW; 19.0 HP) at 3,600 rpm
Max. torque 46.4 Nm (4.73 kg·m; 34.24 ft·lb) at 2,200 rpm
Cooling system Forced air
Air cleaner High-efficiency, heavy-duty air filters
Lubricating system Full pressure
Ignition system Electronic ignition system
Fuel system EFI (electronic fuel injection) system
Fuel used Unleaded gasoline (octane number 86 or higher)
Starting system Electric starter
PTO shaft rotation Counterclockwise (from PTO shaft side)
Dimensions (L x W X H) 376 x 480 x 622 mm (14.8 x 18.9 x 24.5 in)
Dry weight 49.0 kg (108.0 lbs)

Cylinder Block and Head

Cylinder block
Compression ratio: 8.7:1
Cylinder bore: 80.0 mm (3.15 in)
Piston stroke: 69.0 mm (2.72 in)
Cylinder internal diameter (standard): 80.000-80.025 mm (3.1496-3.1506 in)
Number of piston rings (compression / oil): 2/1
Piston style A
Thrust face outer diameter (standard): 79.943-79.961 mm (3.1473-3.1480 in)
Piston pin diameter: 16.995-17.000 mm (0.6691-0.6693 in)
Side clearance (Top): 0.050-0.095 mm (0.0019-0.0037 in)
Side clearance (Second): 0.030-0.075 mm (0.0012-0.00307 in)
Side clearance (Oil): 0.010-0.110 mm (0.0004-0.0043 in)
Ring end gap (Top): 0.250-0.560 mm (0.0100-0.0224 in)
Ring end gap (Second): 0.250-0.560 mm (0.0100-0.0224 in)
Piston style B
Thrust face outer diameter (standard): 79.966 mm (3.1483 in)
Piston pin diameter: 16.995-17.000 mm (0.6691-0.6693 in)
Side clearance (Top): 0.030-0.070 mm (0.0010-0.0026 in)
Side clearance (Second): 0.030-0.070 mm (0.0010-0.0026 in)
Side clearance (Oil): 0.060-0.190 mm (0.0022-0.0073 in)
Ring end gap (Top): 0.100-0.279 mm (0.0039-0.0110 in)
Ring end gap (Second): 1.400-1.679 mm (0.0551-0.0661 in)
Number of main bearings: 2
Crankshaft main journal diameter: 40.913-40.935 mm (1.6107-1.6116 in)
Crankpin journal diameter: 35.955-35.973 mm (1.4155-1.4163 in)
Cylinder head
Valve arrangement: OHV, gear driven
Valves: 2 (4 valves in total)
Valve head diameter (INTAKE): 33.370-33.630 mm (1.3138-1.324 in)
Valve head diameter (EXHAUST): 29.370-29.630 mm (1.1563-1.1665 in)
Valve seat angle (INTAKE): 89°
Valve seat angle (EXHAUST): 89°
Valve seat angle (INTAKE): 45°
Valve seat angle (EXHAUST): 45°
Valve steam diameter (INTAKE): 6.982-7.000 mm (0.2749-0.2756 in)
Valve steam diameter (EXHAUST): 6.970-6.988 mm (0.2744-0.2751 in)
Valve lift minimal (INTAKE): 8.07 mm (0.3177 in)
Valve lift minimal (EXHAUST): 8.07 mm (0.3177 in)
Camshaft journal diameter : 19.962-19.975 mm (0.7859-0.7864 in)

Tightening torque specs

Tightening torque specs
Intake manifold mounting
(torque in 2 increments)
Step 1: 7.4 Nm (0.75 kg·m; 5.5 lb·ft)
Step 2: 9.9 Nm (1.00 kg·m; 7.3 lb·ft)
Connecting rod cap fastener Black Coating: 11.6 Nm (1.2 kgf·m; 8.6 lb·ft)
Gray Metallic Coating: 13.6 Nm (1.4 kgf·m; 10.0 lb·ft)
Cylinder head Nut (torque in 2 increments):
Step 1: 16.9 Nm (1.72 kg·m; 12.5 lb·ft)
Step 2: 35.5 Nm (3.62 kg·m; 26.2 lb·ft)
Bolt (torque in 2 increments)
Step 1: 22.6 Nm (2.31 kg·m; 16.7 lb·ft)
Step 2: 41.8 Nm (4.26 kg·m; 30.8 lb·ft)
Fan 9.9 Nm (1.0 kg·m; 7.3 lb·ft)
Flywheel 71.6 Nm (7.3 kgf·m; 52.8 lb·ft)
Muffler retaining nuts 27.8 Nm (2.8 kgf·m; 20.5 lb·ft)
Spark plug 27 Nm (2.75 kg·m; 20.0 lb·ft)

Service Data

Maximum speed: 3600±50 rpm
Idle speed: 1200±75 rpm
Oil system
Lubrication system: Full pressure
Oil type: API SJ, or higher
Recommended oil: SAE 10W-30, Kohler PRO 10W-50
Oil capacity: W/o oil filter: 1.7 L (1.8 US. qt, 1.5 Imp. qt.)
With oil filter: 1.9 L (2.0 US.qts, 1.7 Imp. qts)
Ignition system
Type: Electronic ignition system
Spark plug: Champion RC12YC or Champion XC12YC
Spark plug gap: 0.76 mm (0.030 in)
Ignition coil air gap 0.280-0.330 mm (0.011-0.013 in)


1. Kohler Command PRO EFI ECH630-ECH749, CH735, CH26, CH745 service manual. Kohler Co. 2023.

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 is an informational database of technical specifications, we are not a parts supplier or a marketplace.

We try to use official documentation and verify the published data, but errors may occur. In addition, specifications of machinery and equipment may vary depending on markets and modifications. We do not recommend the use of this data for spare parts or repairs. Use official service manuals or parts catalogs for your product.

Be the first to comment

Leave a Reply

Your email address will not be published.