Kohler Courage SV710-740 Service Manual page 50

Always use new gaskets when servicing or
reinstalling carburetors. Repair kits are available
which include new gaskets and other components.
Service/repair kits available for Nikki carburetors and
affiliated components are:
Carburetor Repair Kit
Float Kit
High Altitude Kit (1219-2434 m/4,000-8,000 ft.)
Solenoid Assembly Kit
Reassembly is essentially the reverse of the
disassembly procedure. Use new gaskets, springs and
adjusting screws as provided in the carburetor repair
kit. Also use new carburetor and intake manifold
gaskets. Set the idle speed (RPM) adjusting screw (if
equipped) 2-1/4 turns open for initial adjustment and
make final adjustments as described earlier.
The engine is equipped with a centrifugal flyweight
mechanical governor. It is designed to hold the engine
speed constant under changing load conditions. The
governor gear/flyweight mechanism is mounted
inside the crankcase on the oil pan, and is driven
off the gear on the camshaft. The governor works as
follows:
• Centrifugal force acting on the rotating governor
gear assembly causes the flyweights to move
outward as speed increases. Governor spring
tension moves them inward as speed decreases.
• As the flyweights move outward, they cause the
regulating pin to move outward.
• The regulating pin contacts the tab on the cross
shaft causing the shaft to rotate. One end of the
cross shaft protrudes through the crankcase. The
rotating action of the cross shaft is transmitted to
the throttle lever of the carburetor through the
external linkage. See Figure 5-34.
• When the engine is at rest, and the throttle is
in the fast position, the tension of the governor
spring holds the throttle plate open. When the
engine is operating, the governor gear assembly
is rotating. The force applied by the regulating
pin against the cross shaft tends to close the
throttle plate. The governor spring tension and
the force applied by the regulating pin balance
each other during operation, to maintain engine
speed.
• When load is applied and the engine speed and
governor gear speed decreases, the governor
spring tension moves the governor lever to open
the throttle plate wider. This allows more fuel
into the engine, increasing engine speed. As
speed reaches the governed setting, the governor
spring tension and the force applied by the
regulating pin will again offset each other to hold
a steady engine speed.
The governed speed setting is determined by the
position of the throttle control. It can be variable or
constant, depending on the engine application.