How To Lower Boom In Case Of Emergency And When Engine Stops - Hitachi ZAXIS 135US-5B Operator's Manual

How to Lower Boom in Case of Emergency and
When Engine Stops
(Without hose-rupture safety valve)
d
WARNING: Prevent personal injury. Confirm that no
one is under the front attachment before starting the
procedure below.
In case the engine suddenly stops and the engine cannot
restart, lower the boom in the following procedures.
IMPORTANT: Never loosen screw (2) more than 2 turns.
Screw (2) may come off.
1. Loosen lock nut (1) in the control valve at the right.
Loosen screw (2) one half of a turn. The boom lowering
speed can be somewhat adjusted by loosening screw (2)
more.
IMPORTANT: Excessive leakage may result if the screw
and the lock nut are tightened insufficiently. Be sure to
retighten the screw and the lock nut to specifications.
2. After the boom is lowered, tighten screw (2) and tighten
lock nut (1) to the specifications below.
Locknut (1)
Tightening Torque: 13 N·m (1.3 kgf·m)
Bolt (2)
Tightening Torque: 7 N·m (0.7 kgf·m)
OPERATING THE MACHINE
5-44
2 1
ZX135US-5B
ZX225US-5B, 225USLC-5B
MDAA-05-008
2
1
MDAA-05-003
Emergency Valve
1
2
T1V1-03-03-038