Service manual
Table Of Contents
The governor
is
an all-speed governor operating in
response to changes in engine speed to actuate the
control rack in order to maintain engine speed at a
constant level proportional to the set position
of
the accelerator. This governor function
is
in sharp
contrast
to
that
of
a minimum-speed maximum-
speed governor, whose control action
is
to limit
the lowest and highest speeds
of
the engine, leaving
the control
of
intermediate speeds to the operator.
The construction
of
the governor
is
as
illustrated in
the figure above:
The governor consists essentially
of
governor gear
@'
flyweights
rJ],
governor sleeve:§) and speed
control spring
@.
The governor gear
is
mounted on camshaft bushing
® attached
to
the rear end
of
the injection
pump camshaft with round
nut
(§l and
is
pressed
by
slip disc
@'
so that it
is
not damaged even
when the engine
output
torque varies.
The flyweights are mounted on governor shaft.
The radial movement
of
the flyweights due to
centrifugal force
is
transmitted to arm @
to
push
governor sleeve
@ through thrust bearing.
To
this sleeve
is
attached adaptor spring
@.
This
spring opposes the force
of
control spring ®
through spring seat so
as
to
compensate for a
decrease in torque when the engine is running at
low speeds. Floating lever
®
is
hinged at its lower
end
to
supporting lever (IT) mounted on control
lever shaft
C§.:)
and
is
connected at its upper end
to
control rack through shackle
@l.
To the mid·part
of
this floating lever
is
fitted connecting pin ®
through which the movement
of
the flyweights
is
transmitted to the control rack. Damper spring,
which
is
mounted on the end
of
control rod, serves
to prevent engine hunting
as
when the engine
speed
is
suddenly decreased. Stopper lever
CD
is
provided
to
move the contro:
r~ck
to
"stop"
posi·
tion.
Engine stalling, which may often occur when the
load
is
suddenly increased,
is
prevented
by
torque
spring. The timing mark provided on the camshaft
bushing and the timing pointer on the governor
housing are conveniently utilized in determining
the beginning
of
injection in the No. 1 cylinder
during assembly job.
A-Timing
mark
Timing
mark on injection
pump
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