Operation and maintenance manual

DX140R/DX140LCROperation
3-36
To activate breaker
1. Set breaker selector switch to "II"
(BREAKER) position.
2. Press lower button on top of right-hand work lever
(joy
stick) to activate hydraulic breaker.
3. Release lower button on top of right-hand work lever
(joy
stick) to deactivate hydraulic breaker.
Relief Valve Adjustment
1. Cap pipe on arm end, using a cap capable of handling
350.0
kg/cm
2
(5,000 psi) under the condition of
disconnecting hose to hydraulic breaker.
2. Adjust pump pressure using activating the breaker, and
watch
ing the pressure displayed on the instrument panel.
Press the display selector button to show digital pressure
reading. (A separate pressure gauge is not required.)
3. Adjust the relief valve pr
essure by turning the adjustment
screw of breaker relief valve. The relief valve is installed on
the left side of the upper structure behind the boom. (Do
not use the overload relief valve on the lower part of control
valve for the breaker relief valve.)
FG000117
O
II
I
Figure 83 Right-hand Work Lever (Joystick)
FG014414
Figure 84
WARNING
AVOID DEATH OR SERIOUS INJURY
If the relief valve pressure is adjusted while the
hydraulic br
eaker is connected, there is possibility
that a high-pressure spike or setting could break a
hose or pipe. Personal injury or death could result
from a hydraulic hose or pipe failure.