Komatsu PC138USLC Operation & Maintenance Manual page 200

OPERATION
For both normal temperatures and cold temperatures, carry out the following operation.
16. Check that fuel control dial (4) is at a point midway between low
idling (MIN) and full speed (MAX).
If it is not at the midway position, set it to the midway position
and run the engine at a mid-range speed before operating.
17. Before starting operations, repeat the following operations
slowly 3 to 5 times to circulate warm oil through the control
circuits.
Boom operation
Arm operation
Bucket operation
When carrying out swing operations, release swing lock switch
(2), check that swing lock monitor (19) goes out, then operate
the swing.
Swing operation
Travel (Lo) operation
RAISE (E) ←→ LOWER (F)
IN (B) ←→ OUT (A)
CURL (D) ←→ DUMP (C)
Left (G) ←→ Right (H)
FORWARD (A) ←→ REVERSE (B)
MACHINE OPERATIONS AND CONTROLS
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