Hitachi ZX200-5G Workshop Manual page 230

Disassembly of Regulator
 The regulators are used for pump 1 and pump 2. The
inner structure in the regulator is fully identical, and
the difference is only in its accessories. The regulator
for pump 2 is explained here.
IMPORTANT: As the setting changes, do not
disassemble regulator adjusting screw parts
(4, 5, 16, 17, 18, and 19). When it should be
disassembled, adjust according to the procedures
of performance test after assembling.
1. Remove socket bolts (2) (2 used). Remove solenoid
valve (3) from casing (9).
l : 8 mm
IMPORTANT: Do not turn set bolt (16) and lock nuts
(17, 18, 19). If turning, the setting changes.
2. Remove socket bolts (20) (4 used) from cover (15).
Remove the cover (15) assembly from casing (9). Set
bolt (16) and stopper assembly (21) are removed
with the cover (15) assembly together at this time.
l : 6 mm
3. Remove O-ring (22) from stopper assembly (21).
IMPORTANT: Do not turn lock nuts (4, 5). If turning,
the setting changes.
4. Remove socket bolts (20) (4 used) from cover (1).
Remove the cover (1) assembly from casing (9).
Stopper assembly (6) is removed with the cover (1)
assembly together at this time.
l : 6 mm
SECTION 3 UPPERSTRUCTURE
Group 8 Pump Device
W3-8-4-2
5. Remove O-ring (7) from stopper assembly (6).
6. Remove springs (23, 24) from casing (9).
7. Insert a round bar into the hole of casing (9). Push
the spool (26) end. Remove cylinder (28), sleeve
(25), and spool (26) from casing (9). Piston (27) is
removed with cylinder (28) together at this time.
8. Remove piston (27), O-rings (29, 31), and backup
ring (30) from cylinder (28).
9. Remove spring (8) from casing (9).
10. Insert a round bar into the hole of casing (9). Push
the spool (10) end. Remove cylinder (13), sleeve
(11), and spool (10) from casing (9). Piston (12) is
removed with cylinder (13) together at this time.
11. Remove piston (12) and O-ring (14) from cylinder
(13).