Komatsu 830E-AC Shop Manual page 751

6. Remove plug (4, Figure 8-10) from end of spool
(7). Remove spring seat (2) and spring (3).
Remove poppet (5) and spool end (6).
NOTE: Pay special attention to poppets (5, 10 and
25, Figure 8-10) during removal to ensure proper
location during reassembly. Poppets may be
identified with a colored dot; red, white or green. If
poppets are not color coded, use the following chart
for identification:
POPPET
ORIFICE DIAMETER
COLOR
White 1.6 mm (0.063 in.)
Green 2.4 mm (0.093 in.)
Red 2.8 mm (0.110 in.)
7. Repeat step 6 for the opposite end of spool (7)
and the top end of spool (23).
8. Remove spool end (22), spring retainer (20)
and spring (21).
9. Remove cover (16), remove O-rings (18 & 19).
Cleaning and Inspection
1. Discard all O-rings and backup rings. Clean all
parts in solvent and blow dry with compressed
air.
2. Inspect all springs for breaks or distortion.
Inspect poppet seating surfaces for nicks or
excessive wear. All seats must be sharp and
free of nicks.
3. Inspect all bores and surfaces of sliding parts
for nicks, scores or excessive wear.
4. Inspect all poppets in their respective bore for
fit. Poppets should move freely without binding
through a complete revolution.
L08038
Assembly
1. Lubricate O-rings (18 & 19, Figure 8-10), with
clean hydraulic oil. Install O-rings in spool hous-
ing and install cover (16). Secure cover in place
with cap screws. Tighten cap screws to 81 N·m
(60 ft lbs) torque.
2. Install spring (3, Figure 8-10) in spool (7). Install
spring seat (2). Apply Loctite
spool end (6). Install spool end (6) and tighten
to 34 N·m (25 ft lbs) torque. Install poppet (5).
Apply Dri-loc #204 to the threads of plug (4).
DRILL
Install plug (4) and tighten to 20 N·m (15 ft lbs)
SIZE
torque.
#52
NOTE: Poppets 5, 10 and 25 may be color coded
#42
and must be installed in their original location.
#35
3. Repeat step 2 for the opposite end of spool (7).
Make sure spring (8) is blue in color.
4. Lubricate spool assembly (7) and carefully
install in spool housing (15). Make sure the "V"
groove in spool (7) is in the up position, or
toward cover (1).
5. Repeat step 2 for the top end of spool (23). The
bottom end of spool (23) does not contain a
poppet or plug. Install spring (21) which is blue
in color, spring seat (20) and spool end (22).
Apply Loctite to spool end threads. Install spool
end (22) and tighten to 34 N·m (25 ft lbs)
torque.
6. Lubricate the assembled spool (23) and install
in spool housing (15). Make sure the "V" groove
is in the up position, or toward cover (1).
NOTE:
interchangeable. Make sure spool (23) is installed
toward the base port of the spool housing.
7. Install new O-ring and backup ring on restrictor
poppet (1, Figure 8-8). Install restrictor poppet
in housing.
8. Install new O-rings (12 & 13, Figure 8-10).
9. Install new O-ring and backup ring on poppet
(1, Figure 8-7). Make sure the small steel ball is
installed in poppet (1). Install poppet (1) in
cover (3).
10. Install covers (1, Figure 8-10). Secure cover in
place with cap screws. Tighten cap screws to
81 N·m (60 ft lbs) torque.
Hoist Circuit Component Repair
®
Spools (7) and (23)
to the threads of
are physically
L8-9