Kohler K9J Service Manual page 52

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SECONDARY
ADJUSTMENT
PRESSURE CHAMBER
(PRIMARY - 10 PSI)
CHAMBER
SECONDARY DIAPHRAGM
Figure 6-38. Two Stage Regulator.
Adjust the two stage regulator as follows.
1 . Turn the secondary adjustment counterclock-
wise as far as it will go. Then turn it clockwise
3 turns.
2. Connect a source of clean compressed air of
at least 25 psi to the regulator inlet and de-
press primer button 3 times.
3. Connect a 0 to 15 psi pressure gauge to the
fuel outlet and press and hold the primer but-
ton. The pressure gauge should read approxi-
mately 2 psi and hold steady at this reading. If
pressure rises slowly, the primary valve is
leaking and the regulator must be replaced. If
pressure remains constant, proceed.
4. Remove pressure gauge and cover outlet with
a film of soap solution. If a bubble forms, the
secondary valve is leaking.
5. Slowly turn the secondary adjustment to the
left until the bubble expands, then to the right
one complete turn to stop the leak. If leaking
persists, replace the regulator.
GOVERNOR
Engine speed governors in the K series of engines
(with the exception of the K91) are of the centrifu-
gal flyweight mechanical type. The K91 utilizes a
flyball. The governor gear and flyweight mecha-
nism are contained within the crankcase. The gov-
ernor gear is driven by a gear on the camshaft.
Operation
In operation, centrifugal force causes the fly-
weights (or flyball) to move outward with an in-
6.26
crease in speed and inward with a decrease. As
the flyweights move outward, they force the regu-
lating pin of the assembly to move outward. The
regulating pin contacts the tab on the cross shaft,
causing the shaft to rotate with changing speed.
One end of the cross shaft protrudes through the
side of the crankcase. Through external linkage
attached to the cross shaft, the rotating action is
transmitted to the throttle on the carburetor.
When the engine is not running, the governor
spring holds the throttle in the open position.
When a normal load is applied to an operating en-
gine, the speed tends to decrease. The resulting
rotation of the cross shaft acts against the gover-
nor spring, opening the throttle wider. This action
admits more fuel, restoring engine speed. As
speed again reaches the governed setting, the
shaft rotates to close the throttle valve enough to
maintain governed speed.
Governed speed may be at a fixed point as on
constant speed applications or variable as deter-
mined by a throttle control setting.
Initial Adjustment- K91, K141, K161, K181
Governors are adjusted at the factory. Further ad-
justment should not be necessary unless the gov-
ernor arm or linkage work loose or become dis-
connected. The need for governor adjustment may
be indicated by engine speed surges or hunting
with changes in load or by a considerable drop in
engine speed when a normal load is applied. The
internal governor mechanism is basically similar for
all K series engines. The external mechanism is
different on the K241 through K341 models. Be
sure to follow the adjustment procedure for the
model engine being serviced.