Hitachi EX20UR-2 Manual page 65

Housing Control Piston Bushing
4. Clearance between bushing bore and control pis-
ton:
(D-d) must be 0.5 mm or less.
6. Wear amount of the valve plate sliding surface
(with cylinder block):
The surface must be free from abnormal scratches,
wear or seizure.
Scratch depth or wear amount must be 0.030 mm
or less.
W509-02-04002
Valve Plate Sliding Surface
5. Wear amount of the cylinder block sliding surface
(with valve plate):
The surface must be free from abnormal scratches,
wear or seizure.
Scratch depth or wear amount must be 0.030 mm
or less.
W509-02-04-001
Cylinder Block Sliding Surface
UPPERSTRUCTURE I Pump Device
W507-02-04-011
W02-03-32