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Kohler Command CV493S

General Technical Data

Kohler CV493S Engine Specifications

Engine Model ..................... Kohler Command CV493S
Engine Type ..................... 4-cycle OHV vertical shaft air-cooled gasoline
Number of Cylinders ..................... Single
Piston Displacement, cc (cu.in) ..................... 490 (29.9)
Cylinder Bore, mm (in) ..................... 90.0 (3.60)
Piston Stroke, mm (in) ..................... 77.0 (3.03)
Engine Power, Hp (kW) ..................... 18.0 (13.4)
Maximum Torque, Nm (ft-lb) ..................... 38.1 (28.2)
Fast Idle Speed, rpm ..................... 2400
Low Idle Speed, rpm ..................... 1400
Compression Ratio ..................... 8.7:1
Cooling System ..................... Air Intake
Lubrication System ..................... Full-Pressure
Oil Pump Type ..................... Gerotor
Oil Filter Type ..................... Full-flow
Oil Capacity, L (qt) ..................... 1.9 (2.0)
Electrical System Rating, Volts ..................... 12
Ignition System Type ..................... Electronic with Spark Advance
Recommended Battery ..................... 12V-250CCA

Fuel System

Fuel System Type ..................... Carburetor
Carburetor Type ..................... Float fixed main jet
Carburetor Model ..................... Walbro or Nikki
Fuel Pump Type ..................... Diaphragm, mechanical
Fuel Filter Type ..................... In-line
Governor Type ..................... Centrifugal, mechanical
Air Cleaner Type ..................... Replaceable paper element

Dimensions and Weight

Overall Length, mm (in) ..................... 465 (18.2)
Overall Width, mm (in) ..................... 375 (14.8)
Overall Height, mm (in) ..................... 320 (12.7)
Dry Weight, kg (lbs) ..................... 42 (90)

Kohler CV493S Maintenance Data

Ignition System

Spark Plug Type ..................... Champion RC12YC
Spark Plug Thread Size, mm (in) ..................... 14 (0.55)
Spark Plug Reach, mm (in) ..................... 19.1 (0.75)
Spark Plug Gap, mm (in) ..................... 1.02 (0.040)
Module Air Gap, mm (in) ..................... 0.200-0.300 (0.008-0.012)
Spark Plug Torque, Nm ..................... 24.4-29.8

Engine Oil

Engine Oil Type (Summer) ..................... SAE 10W-30
Engine Oil Type (Winter) ..................... SAE 5W-20, 5W-30
Oil Classification (API Service) ..................... SG, SH, SJ or higher
Oil Capacity (w/o Filter), L (qts) ..................... 1.7 (1.8)
Oil Capacity (with Filter), L (qts) ..................... 1.9 (2.0)

Carburetor Adjustments

Main Fuel ..................... 2-1/4 to 2-1/2 turns
Idle Fuel ..................... 3/4 to 1 full turn
Low Idle Speed, rpm ..................... 1200±75
High Idle Speed, rpm ..................... 3600±50

Service Intervals

Service Precleaner Element ..................... Every 25 hours
Replace Air Cleaner Element ..................... Every 100 hours
Change Engine Oil ..................... Every 100 hours
Check Carburetor Adjustment ..................... Every 100 hours
Check Spark Plug Condition and Gap ..................... Every 200 hours
Replace Oil Filter ..................... Every 200 hours
Replace Spark Plug ..................... Every 300 hours
Check and Adjust Valve Clearance ..................... Every 300 hours

Kohler CV493S Service Specifications

Cylinder Block

Cylinder Bore I.D (Std) ..................... 90.000-90.025 mm (3.5433-3.5443 in.)
Cylinder Bore I.D (Wear Limit) ..................... 90.063 mm (3.5458 in.)
Cylinder Bore I.D (Max Out-of-Round) ..................... 0.12 mm (0.0047 in.)
Cylinder Bore I.D (Max Taper) ..................... 0.05 mm (0.0020 in.)
Crankshaft End Play (Free) ..................... 0.0575-0.4925 mm (0.0022-0.0193 in.)
Crankshaft Bore I.D (Crankcase, Std) ..................... 44.965-44.990 mm (1.7702-1.7712 in.)
Crankshaft Bore (Crankcase, Wear Limit) ............... 44.9758-45.0012 mm (1.7707-1.7717 in.)
Crankshaft Bore Clearance (Crankcase) ............... 0.0300-0.0770 mm (0.0011-0.0030 in.)
Crankshaft Bore I.D (Oil Pan, Std) ..................... 41.965-42.003 mm (1.6521-1.6536 in.)
Crankshaft Bore I.D (Oil Pan, Wear Limit) ............ 41.9760-42.0141 mm (1.6526-1.6541 in.)
Crankshaft Bore Clearance (Oil Pan) ................... 0.0300-0.0880 mm (0.0011-0.0034 in.)
Crankshaft Bearing Journal O.D (Flywheel, Std) ..................... 44.913-44.935 mm (1.7682-1.7691 in.)
Crankshaft Bearing Journal O.D (Flywheel, Wear Limit) ..................... 44.84 mm (1.765 in.)
Crankshaft Bearing Journal O.D (Oil Pan, Std) ..................... 41.915-41.935 mm (1.6502-1.6510 in.)
Crankshaft Bearing Journal O.D (Oil Pan, Wear Limit) ..................... 41.86 mm (1.648 in.)
Connecting Rod Journal O.D (Std) ..................... 38.958-30.970 mm (1.5338-1.5343 in.)
Connecting Rod Journal O.D (Wear Limit) ..................... 38.94 mm (1.5328 in.)
Connecting Rod to Crankpin Clearance (Std) ................... 0.030-0.055 mm (0.0012-0.0022 in.)
Connecting Rod to Crankpin Clearance (Wear Limit) ............... 0.07 mm (0.0025 in.)
Connecting Rod to Crankpin Side Clearance ..................... 0.18-0.41 mm (0.007-0.016 in.)
Connecting Rod to Piston Pin Clearance ..................... 0.015-0.028 mm (0.0006-0.0011 in.)

Cylinder Head and Valves

Cylinder Head (Max Out of Flatness) ..................... 0.076 mm (0.003 in.)
Hydraulic Valve Lifter to Crankcase Clearance .................. 0.0124-0.0501 mm (0.0005-0.0020 in.)
Intake Valve Stem to Guide Clearance ..................... 0.038-0.076 mm (0.0015-0.0030 in.)
Exhaust Valve Stem to Guide Clearance ..................... 0.050-0.088 mm (0.0020-0.0035 in.)
Intake Valve Guide I.D (Std) ..................... 7.038-7.058 mm (0.2771-0.2779 in.)
Intake Valve Guide I.D (Wear Limit) ..................... 7.134 mm (0.2809 in.)
Exhaust Valve Guide I.D (Std) ..................... 7.038-7.058 mm (0.2771-0.2779 in.)
Exhaust Valve Guide I.D (Wear Limit) ..................... 7.159 mm (0.2819 in.)
Valve Guide Reamer Size (Std) ..................... 7.048 mm (0.2775 in.)
Intake Valve Minimum Lift ..................... 8.96 mm (0.353 in.)
Exhaust Valve Minimum Lift ..................... 9.14 mm (0.360 in.)
Nominal Valve Seat Angle ..................... 45 deg
Rocker Arm I.D (Std) ..................... 15.837-16.127 mm (0.63-0.64 in.)
Rocker Arm I.D (Wear Limit) ..................... 16.13 mm (0.640 in.)
Rocker Shaft O.D (Std) ..................... 15.90-15.85 mm (0.63 in.)
Rocker Shaft O.D (Wear Limit) ..................... 15.727 mm (0.619 in.)
Camshaft End Play (Free) ..................... 0.088-0.393 mm (0.003-0.015 in.)
Camshaft Running Clearance ..................... 0.025-0.105 mm (0.0010-0.0041 in.)
Camshaft Bore I.D (Std) ..................... 20.000-20.025 mm (0.7874-0.7884 in.)
Camshaft Bore I.D (Wear Limit) ..................... 20.038 mm (0.7889 in.)
Camshaft Bearing O.D (Std) ..................... 19.962-19.975 mm (0.7859-0.7864 in.)
Camshaft Bearing O.D (Wear Limit) ..................... 19.959 mm (0.7858 in.)

Piston and Piston Rings

Piston to Piston Pin Clearance ..................... 0.006-0.017 mm (0.0002-0.0007 in.)
Piston Pin Bore I.D (Std) ..................... 19.006-19.012 mm (0.7483-0.7485 in.)
Piston Pin Bore I.D (Wear Limit) ..................... 19.025 mm (0.7490 in.)
Piston Pin O.D (Std) ..................... 18.995-19.000 mm (0.7478-0.7480 in.)
Piston Pin O.D (Wear Limit) ..................... 18.994 mm (0.74779 in.)
Piston Pin End I.D (Std) ..................... 19.015-19.023 mm (0.7486-0.7489 in.)
Piston Pin End I.D (Wear Limit) ..................... 19.036 mm (0.7495 in.)
Top Compression Ring Groove Clearance ..................... 0.060-0.105 mm (0.0023-0.0041 in.)
Middle Compression Ring Groove Clearance ..................... 0.040-0.085 mm (0.0015-0.0033 in.)
Oil Control Ring Groove Clearance ..................... 0.036-0.186 mm (0.0014-0.0073 in.)
Top Compression Ring End Gap ..................... 0.28-0.51 mm (0.011-0.020 in.)
Center Compression Ring End Gap ..................... 0.22-0.48 mm (0.008-0.018 in.)
Oil Control Ring End Gap ..................... 0.250-0.760 mm (0.0098-0.0299 in.)
Piston Thrust Face O.D (Std) ..................... 89.951-89.969 mm (3.5413-3.5420 in.)
Piston Thrust Face O.D (Wear Limit) ..................... 89.824 mm (3.5363 in.)
Piston Thrust Face to Cylinder Bore Clearance ............... 0.031-0.043 mm (0.0012-0.0016 in.)

Balance Shaft

Balance Shaft End Play ..................... 0.0575-0.3625 mm (0.0027-0.0137 in.)
Balance Shaft Running Clearance ..................... 0.0250-0.1520 mm (0.0009-0.0059 in.)
Balance Shaft Bore I.D (Std) ..................... 20.000-20.025 mm (0.7874-0.7884 in.)
Balance Shaft Bore I.D (Wear Limit) ..................... 20.038 mm (0.7889 in.)
Balance Shaft Bearing Surface O.D (Std) ..................... 19.962-19.975 mm (0.7859-0.7864 in.)
Balance Shaft Bearing Surface (Wear Limit) ..................... 19.959 mm (0.7858 in.)

Tightening Torque Specs

Cylinder Head ..................... 20, 40.7 Nm (15, 30 ft-lb)
Rocker Pedestal ..................... 11.3 Nm (8.3 ft-lb)
Fuel Bowl Retaining Screw ..................... 5.1-6.2 Nm (3.8-4.6 ft-lb)
Starter Mounting Screw ..................... 15.3 Nm (11.3 ft-lb)
Fan Mounting Screw ..................... 9.9 Nm (7.3 ft-lb)
Flywheel Retaining Screw ..................... 66.4 Nm (49 ft-lb)
Fuel Pump ..................... 9.0 Nm (6.7 ft-lb)
Spark Plug ..................... 24.4-29.8 Nm (18-22 ft-lb)
Ignition Module ..................... 6.2 Nm (4.6 ft-lb)
Muffler Retaining Nuts ..................... 24.4 Nm (18.0 ft-lb)
Oil Filter Screw ..................... 10.4-12.7 Nm (7.5-9.2 ft-lb)
Oil Pan Screw ..................... 24.4 Nm (18.0 ft-lb)
Oil Pump Cover ..................... 6.2 Nm (4.6 ft-lb)
Governor Control Lever ..................... 9.9 Nm (7.3 ft-lb)
Valve Cover Screw ..................... 10.7 Nm (7.9 ft-lb)
Rocker Arm Screw ..................... 11.3 Nm (8.4 ft-lb)
Rocker Arm Pivot Stud ..................... 11.3 Nm (8.4 ft-lb)
Connecting Rod Bolt ..................... 11.3-22.7 Nm (8.4-16.7 ft-lb)