Komatsu WA800-3E0, Operation & Maintenance Manual

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OPERATION
OPERATION
3-110
SHIFTING TRANSMISSION WHEN THRUSTING BUCKET IN
When thrusting the bucket into the facing to carry out excava-
tion, do not shift down with the accelerator pedal depressed
(with the engine speed raised). If the transmission shifts down
when the engine speed is high, there will be an excessive load
on the engine, torque converter, transmission, axles, final drive,
and the whole power train.
When shifting down to 1st and thrusting the bucket into the fac-
ing, release the accelerator pedal to reduce the engine speed
before shifting down. Then gradually depress the accelerator
pedal. If the accelerator is operated suddenly after shifting
down, there will be excessive load brought to bear on the
engine and power train.
ARTICULATING MACHINE DURING DIGGING OPERATIONS
Do not carry out operations with the machine articulated. If the
machine is articulated, the direction of force will be different for
the front wheels and rear wheels. As a result, the power when
traveling will not be transmitted fully to the front wheels, so this
will reduce the digging force and bring an excessive load to
bear on the center hinge pin. In addition, even with the front
wheels, the power will not be transmitted uniformly to the left
and right wheels. The load will be brought to bear on one
wheel, so this will reduce the service life of the tire on one side.
If digging work is carried out with the machine articulated, the
overall stability of the machine will be poor and there is danger
of the machine tipping over.
When carrying out operations, do not articulate the machine.
Drive straight forward and thrust the bucket in. If this is done,
the load on the bucket will be uniform, so this makes it possible
to avoid load on one side and makes it easier to load the
bucket.
BUCKET DUMP ANGLE WHEN DIGGING OR LOWERING ROADBED
Do not set the cutting edge of the bucket at a large angle to the
ground surface when digging or lowering the roadbed. Keep
angle (a) between the bucket and the ground surface to a max-
imum of 8°. If angle (a) between the cutting edge of the bucket
and the ground surface is more than 8° when digging or lower-
ing the roadbed, there is danger of damage to the work equip-
ment.