Hitachi ZAXIS 120-6 class Operator's Manual page 86

 Do not modify the machine without authorization.
Never attempt to modify the air inlet and exhaust
parts such as the air duct, aftertreatment device
and the exhaust piping. Also never attempt to
disassemble the aftertreatment device. Avoid giving
shocks on the aftertreatment device by striking
elements with other objects or dropping the device.
Failure to do so may affect the aftertreatment device,
possibly damaging it or lowering its performance.
 White smoke may be generated during the
aftertreatment device regeneration. Do not attempt
to perform a manual regeneration in a poorly
ventilated area.
 Consult your authorized dealer for checking or
repairing the aftertreatment device.
f
NOTE:
 White deposits may accumulate inside the aftertreatment
device. The aftertreatment device is automatically
regenerated to remove accumulated white deposits at
regular intervals. It is called auto-regeneration. The auto-
regeneration may start during operation of the machine;
you can continue to operate the machine. (Refer to the
page 1-25)
 Do not stop the engine during regeneration unless
absolutely necessary.
 The auto-regeneration may be terminated depending on
the machine operating condition.
 Usually, auto-regeneration starts 30 hours after the
previous regeneration (either auto or manual).
OPERATOR'S STATION
1-4