Kohler Command PRO ECH749 Service Manual

7.2
Section 7
Electrical System and Components
Normal: A plug taken from an engine operating under
normal conditions will have light tan or gray colored
deposits. If the center electrode is not worn, a plug
in this condition could be set to the proper gap and
reused.
Carbon Fouled: So , sooty, black deposits indicate
incomplete combustion caused by a restricted air
cleaner, over-rich fuel mixture, weak ignition, or poor
compression.
Worn: On a worn plug, the center electrode will be
rounded and the gap will be greater than the specifi ed
gap. Replace a worn spark plug immediately.
Wet Fouled: A wet plug is caused by excess fuel or
oil in the combustion chamber. Excess fuel could be
caused by a restricted air cleaner or rich air/fuel ratio.
Oil in the combustion chamber is usually caused by
a restricted air cleaner, a breather problem, or worn
piston rings, cylinder walls or valve guides.
Overheated: Chalky, white deposits indicate very high
combustion temperatures. This condition is usually
accompanied by excessive gap erosion. Lean air/fuel
ratio, an intake air leak, or incorrect spark timing are
normal causes for high combustion temperatures.

Kohler Command PRO ECH749 Specifications

General

Fuel System	Carburetor
Starter	Electric
Governor Type	Mechanical
Lubrication System	Full Pressure
Fuel Type	Gasoline
Crankshaft Orientation	Horizontal
Bore	3.27 in (83 mm)
Cooling System	Air
Oil Type	SAE 10W-30
Spark Plug Gap	0.030 in (0.76 mm)
Valve Clearance - Intake	0.004 - 0.006 in (0.10 - 0.15 mm)
Crankshaft Type	Varies by model
Crankshaft Thread Size	Varies by model
Crankshaft Length	Varies by model
Crankshaft Diameter	Varies by model
Type	Overhead Valve (OHV)