Precautions For Using Floating Seal - Hitachi ZX200-5G Workshop Manual

Precautions for Using Floating Seal

1. In general, replace the floating seal with a new one
after disassembling.
If the floating seal is required to be reused, follow
these procedures:
 Keep seal rings together as a matched set with seal
ring (1) surfaces together. Apply oil onto sliding
surface (e) of seal ring (1).
 Check sliding surface (e) of seal ring (1) for scuffing,
scoring, corrosion, deformation, or uneven wear.
Check the step part of seal ring (1).
 Check O-ring (2) for tears, breaks, deformation, or
hardening.
2. If incorrectly assembled, oil leakage or damage
will occur. Be sure to do the following to prevent
trouble.
 Clean the floating seal and seal mounting bores with
cleaning solvent.
Use a wire brush to remove mud, rust, or dirt from
seal mounting bores. After cleaning, thoroughly dry
parts with compressed air.
 Clean seal ring (1) and O-ring (2) mounting bores.
Check the bore surface for scuffing or scoring by
touching the surface with finger.
 After installing the floating seal, check that O-ring (2)
is not twisted, and that it is installed correctly on seal
ring (1).
 After installing the floating seal, check that O-ring
(2) and seal ring sliding surface (e) is parallel with
seal mating surface (f ) by measuring the distances
(e) and (f ) at point (A) and (B), as illustrated. If these
distances differ, correct O-ring (2) seating.
SECTION 4 UNDERCARRIAGE
Group 2 Travel Device
W4-2-5-1
a
b
a - Correct
b - Incorrect
a
A
A=B
a - Correct
b - Incorrect
1
W178-02-11-001
2
c
d
W178-02-11-002
c - Twist of O-Ring
d - Bend of O-Ring
f
b
A
e
2
B
B
A≠B
W178-02-11-003
e - Sliding Surface
f - Seal Mating Surface