Hitachi Zaxis 33U-5A Operator's Manual page 218

Quick Coupler
1. Connecting Coupler
Always grasp the coupler by its clamp section. Push the
body straight until the dust prevention cover retracts
approx. 2 mm. Then, pull the clamp section straight to
make sure that the coupler is properly connected and
will not be disconnected.
d
CAUTION: If the coupler is grasped and pushed by
the dust prevention cover, or not pushed until the
dust prevention cover retracts, incomplete connection
of the coupler may result, causing the coupler to
disconnect when oil pressure increases. Even if the
coupler is incompletely connected, if pulling force
is diagonally applied, the coupler may be difficult
to disconnect. However, the coupler may be easily
disconnected in this case when oil pressure increases.
Take care not to diagonally push the coupler. Failure to
do so damage to the inner parts, cause oil leak, and/or
unexpected coupler disconnection may result.
2. Disconnecting Coupler
Be sure to disconnect the coupler only after removing
any foreign matter adhered such as soil adhered to the
joint with cleaning oil.
 While grasping the clamp section, push the body straight
approx. 2 mm.
 While pushing the body, pull the dust prevention cover.
 Pull the overall coupler together along with the dust
prevention cover to disconnect the coupler.
MAINTENANCE
7-50
Dust Prevention
Clamp Section
Cover
Click
Approximately 2 mm
M1LA-07-014
M1LA-07-015
M1LA-07-016
M1LA-07-017
M1LA-07-018