Komatsu Galeo PC138US-8 Shop Manual page 357

30 Testing and adjusting
Adjusting
a The unload valve and safety-suction valve for
lowering the boom cannot be adjusted.
1. Adjusting work equipment and travel relief
pressure
a If the relief pressure of the work equip-
ment circuit and travel circuit is abnormal,
adjust main relief valves (3) according to
the following procedure.
(3): Main relief valve
q
a When adjusting the main relief valves,
remove the side cover of the control valve.
1) Remove the control valve left side cover.
2) While fixing holder (4), loosen locknut (5).
3) Turn holder (4) to adjust the set pressure.
a If the holder is
Turned to the right, the set pres-
q
sure is increased.
Turned to the left, the set pres-
q
sure is decreased.
a Quantity of adjustment per turn of
holder:
Approx. 20.5 MPa {Approx. 209 kg/cm
4) While fixing holder (4), tighten locknut (5).
3
Locknut: 49 – 58.8 Nm {5 – 6 kgm}
5) After finishing adjustment, check again
that the oil pressure is normal according to
the above described test procedure.
PC138US, USLC-8
2. Adjusting swing relief pressure
a If the swing relief pressure is abnormal,
adjust safety valve (6) of the swing motor
according to the following procedure.
1) While fixing adjustment screw (7), loosen
locknut (8).
2) Turn adjustment screw (7) to adjust the
pressure.
a If the adjustment screw is
q
q
a Quantity of adjustment per turn of
adjustment screw:
Approx. 6.7 MPa {Approx. 68.4 kg/cm
3) While fixing adjustment screw (7), tighten
locknut (8).
3
2
}
4) After finishing adjustment, check again
that the oil pressure is normal according to
the above described test procedure.
SEN02458-01
Turned to the right, the set pres-
sure is increased.
Turned to the left, the set pres-
sure is decreased.
Locknut:
78 – 103 Nm {8 – 10.5 kgm}
2
}
29