Komatsu WA380-6 Operation & Maintenance Manual page 208

OPERATION
ADJUSTING BUCKET POSITIONER
1. Lower the bucket to the ground, set it to the desired digging
angle, return the bucket control lever to the HOLD position, set
the work equipment lock lever to the LOCK position, then stop
the engine.
2. Loosen 2 bolts (1), adjust the position of mounting bracket (4)
of the proximity switch so that the rear tip of bar (2) is in line with
the center of the sensing surface of proximity switch (3), then
tighten bolts to hold the bracket in position.
3. Loosen 2 bolts (5), adjust so that the clearance between bar (2)
and support (6) is 0.5 to 2 mm (0.020 to 0.079 in), then tighten
bolts (5) to hold in position.
4. Loosen 2 nuts (7), adjust so that the clearance between bar (2) and the sensing surface of proximity switch (3)
is 3 to 5 mm (0.118 to 0.197 in), then tighten the nuts to hold in position.
Tightening torque: 17.2 ± 2.5 Nm (1.75 ± 0.25 kgm, 12.7 ± 1.8 lbft)
5. After adjusting, start the engine and raise the lift arm. Operate the bucket control lever to the DUMP position,
then operate it to the TILT BACK position and check that the lever is automatically returned to the HOLD position
when the bucket reaches the desired digging angle.
BUCKET LEVEL INDICATOR
(A) and (B) at the top rear of the bucket are the level indicators.
They check the bucket angle during operations.
(A): Parallel with cutting edge
(B): 90 degrees to cutting edge
OPERATION
3 - 151