Workshop Manual

UPPERSTRUCTURE / Pilot Valve
W2-7-23
Assemble Right and Left Pilot Valves
IMPORTANT: The pilot valve is susceptible to
contamination. Keep the parts clean
when assembling.
NOTE: Table below shows the relations between
each port and the components. Do not
confuse them when assembling.
Port
No.
Spool
(19)
Shim
(2)
Pushers A, B
(9, 10)
1
Outer grooves
(3 used)
2
Without outer
groove
3
Outer grooves
(3 used)
4
Same to the
former one
Same to the
former one
Without outer
groove
Port
No.
Return Springs
(5, 6)
Balance Springs A, B
(3, 4)
1 Short Short
2 Long Long
3 Short Short
4 Long Long
1. Insert same spools (19) (4 used) before
disassembling to the port hole (4 places) on
casing (18).
NOTE: Spool (19) and casing (18) must be
replaced as an assembly.
2. Install special tool (ST 4145) to the port hole on
casing (18).
: 6 mm
IMPORTANT: Refer to the table in left in order to
assemble them correctly.
3. Install spacers (1) (4 used), shim (2) and balance
springs (3, 4) (2 used for each) to spools (19) (4
used). Install return springs (5, 6) (2 used for
each) to casing (18).
4. Install spring guides (7) (4 used) onto return
springs (5, 6) (2 used for each) with the protrusion
facing upward.
5. Install special tool (ST 4146) to the pusher (9, 10)
hole on casing (18). Secure special tool (ST 4146)
by using the bolts (M14, Pitch 2.0 mm).
: 12 mm
W178-02-07-049
6. Install retaining ring (8) to ring holder (ST 4144).
ST 4146
ST 4144
ST 4145