TM 5-3810-288-12
Section III. CONTROLS AND INSTRUMENTS
2-13.
General
To engage the ratchet type lock on this pedal, de-press
This section describes the various controls and
the toe of the pedal while releasing pressure on the
instruments, and provides the operator/crew with
pedal. To disengage the ratchet type lock, depress the
sufficient information to insure proper operation of the
heel of the pedal.
Model M320T truck crane.
Caution: Do not rely on the ratchet brake
locks on the front or rear drum brake pedals to
2-14.
Controls and Instruments
a
General. The crane operating controls and
suspend a load. The operator must remain in a
instruments are shown in figure 2-36. A description of
position of readiness, with feet on pedals, at all
each control is given below.
times that a load is suspended.
Note. The operator must study the information
(8) Front drum brake pedal. Push this pedal
in this section, and be thoroughly familiar with the
down to apply the front drum brake. Release pressure
location and function of each control, before attempting
on the pedal to release the front drum brake. To engage
to operate the machine.
the ratchet type lock on this pedal, de-press the toe of
the pedal while releasing pressure on the pedal. To
Control Identification.
b.
disengage the ratchet type lock, depress the heel of the
pedal.
(1) Swing clutch lever. Push this lever for-ward
(toward the boom point) to swing the upper to the left.
(9) Swing brake lock control. Push this handle
Pull this lever backward to swing the upper to the right.
backward to engage the mechanical swing brake lock.
(2) Front drum clutch lever. Pull this lever
backward (toward the operator) to wrap line on the front
(10) Boom hoist drum pawl control. Push this
drum. Push this lever forward (away from the operator)
handle backward to engage the safety pawl in the boom
to pay line off the front drum.
hoist drum ratchet.
(3) Rear drum clutch lever. Pull this lever
Caution: The boom hoist pawl must be engaged at all
backward (toward the operator) to wrap line on the rear
times, except when lowering the boom. Do not attempt
drum. Push this lever forward (away from the operator)
to engage the boom hoist pawl while lowering the boom.
to pay line off the rear drum.
(11) Front drum pawl control. Push this handle
(4) Boom hoist clutch and brake lever. Pull this
backward to engage the safety pawl in the front drum
lever backward (toward the operator) to wrap line on the
ratchet.
boom hoist drum and raise the boom. Push this lever
forward (away from the operator) to pay line off the boom
Caution: The front drum pawl must be
hoist drum and lower the boom. Return the lever to the
engaged while suspending a load. Do not attempt to
center (neutral) position to apply the boom hoist brake.
engage this pawl while lowering a load.
Note. The boom hoist drum pawl control (item
(12) Rear drum pawl control. Push this handle
10 of this listing) must be used in conjunction with the
backward to engage the safety pawl in the rear drum
boom hoist clutch and brake lever.
ratchet.
(5) Engine throttle control. Move this control
Caution: The rear drum pawl must be
forward to increase the engine speed. Move this control
engaged while suspending a load on the rear drum
backward (toward the operator) to decrease engine
line. Do not attempt to engage this pawl while
speed.
lowering a load.
(6) Swing brake lever. Push this lever fully
(13) Engine clutch lever. Pull this lever fully
forward to apply the swing brake. Pull this lever fully
backward to engage the engine clutch. Push this lever
backward to release the swing brake.
fully forward to disengage the engine clutch.
(7) Rear drum brake pedal. Push this pedal
(14) Horn button. Depress this button to sound
down to apply the rear drum brake. Release pressure on
the warning horn.
the pedal to release the rear drum brake.
(15) Light switches. Use these switches to
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