WABCO MICO ACV-SMO Operating instructions

SINGLE ACCUMULATOR
CHARGING VALVE
Product Explanation,
Operating Information
and Service Instructions
PRODUCT EXPLANATION
The accumulator charging valve is designed for installation
in an open center hydraulic system between the pump and
the downstream secondary hydraulic devices.
The accumulator charging valve supplies oil on demand to
the accumulator from the open center circuit. Accumulator
charging is accomplished at a preset rate (GPM) and is
relatively constant within the preset pressure limits.
The ow to the downstream secondary hydraulic
devices will be reduced fractionally for a short time when
the accumulator is charging. This does not noticeably affect
operation of these components. Full system pressure is
available to the downstream secondary hydraulic devices
at all times provided oil delivery and pressure from the
pump is not impeded.
This accumulator charging valve does not limit pressure
in the accumulator that is from system load downstream
of the ow through port. Over pressure protection is to
be located between the pump and accumulator charging
valve.
OPERATING INFORMATION
End user must provide proper maintenance of valve,
should it become inoperable, by replacing the valve or
servicing it with the proper repair kit. See TABLES 1, 2,
and 3 on pages 3, 5, and 7 for the proper repair kit number.
Observe Service Instruction procedures on following
pages. See Warnings A, B, and C below.
IMPORTANT INFORMATION
Due to allowable operating temperature of accumulator
charging valve avoid contact or burn injury may occur.
A
Be sure system energy is relieved from accumulator
charging valve before removing from machine. See
machine operating instructions for procedures to relieve
system energy.
B
Do not exceed the high limit pressure setting indicated in
TABLE 1, 2, and 3 or system damage or failure may occur.
C
ACV-SMO
This document is intended to provide general information about MICO Products. MICO, Inc. has attempted to present accurate information about MICO Products
in its catalogs, brochures, and other printed materials. MICO, Inc. is not responsible for errors, inaccuracies, or inconsistencies that may exist in any catalog,
brochure, or other printed materials or any damages arising from or related to reliance on information in them. Materials and specications for MICO Products set
forth in catalogs, brochures, and other printed materials are subject to change without notice or obligation. Refer to www.mico.com for the most recent versions of
our literature. If you have any questions concerning MICO Products, please contact MICO, Inc. All MICO Products and service are sold and provided subject to the
MICO Warranty at www.mico.com in effect on the date of sale or supply.
MICO is a trademark and registered trademark of MICO, Inc. MICO is registered in the U.S. Patent and Trademark Ofce as well as in Australia, Canada, Indonesia, Japan, Peoples Republic of China, South Korea, and the European Community.
MICO, Inc.
1911 Lee Boulevard / North Mankato, MN U.S.A. 56003-2507
Tel: [phone] Fax: [phone]
Form No. 81-463-003 Revised 2017-10-24 www.mico.com

MICO, Inc. (2) Form No. 81-463-003 Revised 2017-10-24
SERVICE INSTRUCTIONS
Disassembly
(Refer to Figure 1)
1. Remove plug (1) from housing (7). Remove o-ring (2) from
plug (1). NOTE: Plug (1) is under spring tension.
2. Remove spring (3) and rod (4) from housing (7).
3. Remove plug (8) from housing (7). Remove o-ring (2) from
plug (8).
4. Remove spool (6) from housing (7) through plug (1) end
ONLY. Remove quad ring (5) from spool (6).
5. Earlier Design: Loosen nut (9) on screw assembly (10) and
remove screw assembly (10) from housing (7). Remove o-ring
(11) from screw assembly (10). Remove spring (12), poppet
(13), seat (14), o-ring (15), and washer (16) from housing (7).
Later Design: Some later designs use a directional spring
(12). Directional spring (12) is attached to screw assembly
(10) by means of the small diameter end of spring (12)
being snapped into a groove on the nose end of screw
assembly (10). See Figure 1b. Remove nut (9) and remove
screw assembly (10) from housing (7). Remove o-ring (11)
from screw assembly (10) from nut (9) side of screw assembly.
Remove shim (33), spring (12), steel ball (13), seat (14), o-ring
(15), and washer (16) from housing (7).
6. Remove lter (17) and washer (18) from housing (7).
7. Remove plug (32) from housing (7). Remove o-ring (15) from
plug (32).
8. BEFORE moving screw (30), ACCURATELY MEASURE ITS
DEPTH from the end of housing (7) and record for reassembly
purposes. Remove screw (30) from housing (7).
9. Remove spring (29), retainer (28), and ball (27). Be sure to
keep ball (27) separate from ball (22) for reassembling.
10. Remove pin (31) from screw (30) using a drive pin punch.
NOTE: Be careful not to damage threads.
11. Remove plug (19) from housing (7). Remove o-ring (15) from
plug (19). NOTE: Be careful not to damage threads.
12. Remove spring (20), stop (21), and ball (22) from housing (7).
13. Place housing (7) on bench with plug (19) end down. Spool
(23) may or may not fall out at this point.
14. Using a 6.3-7.9 mm (0.25-0.31 in) diameter wood or plastic
dowel, carefully remove insert (24) and spool (23) from hous-
ing (7). Insert (24) must come out plug (19) end of housing (7).
Be careful not to scratch or mar valve seats on insert (24).
15. Remove spool (23) from insert (24). Remove o-rings (25 & 26)
from insert (24).
Assembly
(Refer to Figure 1)
WASH ALL PARTS WITH CLEAN SOLVENT AND DRY. LUBRICATE
ALL RUBBER PARTS WITH CLEAN SYSTEM FLUID PRIOR TO
ASSEMBLY. BE SURE ENTIRE ASSEMBLY PROCEDURE IS
DONE WITH CONTAMINATION FREE METHODS.
1. Install new o-ring (2) on plug (8). Install plug (8) into housing
(7) and torque 122.0-135.6 N∙m (90-100 lb∙ft).
2. Install new quad ring (5) on spool (6). Be sure quad ring (5)
does not twist in groove.
3. Lubricate spool (6) with clean system uid and insert into
housing (7) as shown in Figure 1.
4. Install spring (3) and rod (4) into housing (7).
5. Install new o-ring (2) on plug (1). Install plug (1) into housing
(7) and torque 122.0-135.6 N∙m (90-100 lb∙ft).
6. Install new o-rings (25 & 26) on insert (24) and install insert
(24) into housing (7). Note direction of assembly. Seat insert
(24) with 12.7 mm (0.50 in) diameter wood or plastic dowel.
7. Install spool (23) into insert (24) in housing (7). Note direction
of spool (23), long shoulder end is up toward end plug (19),
see Figure 1a.
8. Install ball (22) on insert (24) in housing (7). Install stop (21)
over ball (22) and spring (20) over stop (21).
9. Install new o-ring (15) on plug (19) and carefully install into
housing (7), centering spring (20). Torque plug (19)
47.5-54.2 N∙m (35-40 lb∙ft).
10. Turn housing (7) so plug (8) is vertically upward. Install ball
(27) in housing (7). Be sure ball (27) is centered in bottom of
hole. Install retainer (28) and spring (29) into housing (7).
11. Insert new pin (31) in screw (30). Be sure pin (31) is aligned
properly and is evenly driven into screw (30). NOTE: Be
careful not to damage threads.
12. Thread screw (30) in housing (7) to the depth recorded during
disassembly.
13. Install new o-ring (15) on plug (32). Install plug (32) in housing
(7) and torque 47.5-54.2 N∙m (35-40 lb∙ft).
14. Install washer (18) and new lter (17) in housing (7).
15. Earlier Design: Install new o-ring (11) on screw assembly
(10). Install washer (16), new o-ring (15), seat (14), new pop-
pet (13), spring (12), and screw assembly (10) into housing (7).
Torque screw assembly (9) 24.4-29.8 N∙m (18-22 lb∙ft). Then
install nut (9) on screw assembly (10) and torque nut
43.4-51.5 N∙m (32-38 lb∙ft).
Later Design: Some later designs use a directional spring
(12). Directional spring (12) is attached to screw assembly
(10) by means of the small diameter end of spring (12)
being snapped into a groove on the nose end of screw
assembly (10). If necessary, reattach the small diameter of
spring (12) into the groove on the nose end of screw
assembly (10) using a slight twisting motion. See Figure
1b. Install new o-ring (11) on screw assembly (10) from nut (9)
side of screw assembly. Install washer (16), new o-ring (15),
seat (14), steel ball (13), and spring (12) in housing (7). Fully
lubricate shim (33) with clean system uid and install in hous-
ing (7) on end of seat (14). Install screw assembly (10) in
housing (7). Torque screw assembly (10) 24.4-29.8 N∙m
(18-22 lb∙ft). Then install nut (9) on screw assembly (10) and
torque nut 43.4-51.5 N∙m (32-38 lb∙ft).
VALVE ADJUSTMENT
(Refer to Table 1)
1. See machine servicing instructions to properly reinstall
accumulator charging valve. Tee an accurate pressure
gauge on an accumulator line.
2. Start pump and allow approximately one minute for charging
to start (pressure in gauge will read accumulator precharge
plus). If valve does not begin to charge, stop the pump and
remove end plug (32) and turn screw (30) approximately 1/4
turn clockwise. Reinstall end plug (32). Check the high limit
specications (see TABLE 1). Repeat adjustment of screw
(30) as needed until the high limit setting is met. Pressure
limits can be checked correctly only if after each adjustment
of screw (30) the accumulator pressure is reduced below the
low limit setting and the system recharges the accumulator
pressure to its high limit. NOTE: Be sure to reinstall plug
(32) before starting pump.
3. Torque end plug (32) 47.5-54.2 N∙m (35-40 lb∙ft).
Be sure system energy is relieved from accumulator charge
valve before removing from machine. See machine service
manual for procedures to relieve system energy.
NOTE
Locate the model number on the accumulator charging valve and
compare it to the model number in TABLE 1. Be sure you have the
proper service instructions.
NOTE
Observe torque specications as indicated in assembly proce-
dures or system damage or failure may occur.
Do not exceed the high limit pressure setting indicated in TABLE
1 or system damage or failure may occur.

Form No. 81-463-003 Revised 2017-10-24 (3) MICO, Inc.
● Items included in Repair Kit
FIGURE 1
Figure 1a
Model
Number
Repair Kit
Number
Nominal
High Limit (cut out)
bar (PSI)
Nominal
Low Limit (cut in)
bar (PSI)
06-463-006
06-463-008
06-463-010
06-463-014
06-463-016
06-463-018
06-463-020
06-463-022
06-463-024
06-463-026
06-463-028
06-463-036
06-463-038
06-463-040
06-463-044
06-463-048
06-463-050
06-463-054
06-463-056
06-463-058
06-463-060
06-463-064
06-463-066
06-463-068
06-463-070
06-463-078
06-463-082
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
103.4 ± 3.5 (1500 ± 50)
94.8 ± 1.7 (1375 ± 25)
89.6 ± 1.7 (1300 ± 25)
75.8 ± 3.5 (1100 ± 50)
103.4 ± 3.5 (1500 ± 50)
189.6 ± 3.5 (2750 ± 50)
158.6 ± 3.5 (2300 ± 50)
186.2 ± 3.5 (2700 ± 50)
127.6 ± 3.5 (1850 ± 50)
137.9 ± 3.5 (2000 ± 50)
124.1 ± 3.5 (1800 ± 50)
137.9 ± 3.5 (2000 ± 50)
124.1 ± 3.5 (1800 ± 50)
137.9 ± 3.5 (2000 ± 50)
124.1 ± 3.5 (1800 ± 50)
137.9 ± 3.5 (2000 ± 50)
144.8 ± 3.5 (2100 ± 50)
103.4 ± 3.5 (1500 ± 50)
124.1 ± 3.5 (1800 ± 50)
137.9 ± 3.5 (2000 ± 50)
60.3 ± 1.7 (875 ± 25)
158.6 ± 3.5 (2300 ± 50)
89.6 ± 1.7 (1300 ± 25)
158.6 ± 3.5 (2300 ± 50)
158.6 ± 3.5 (2300 ± 50)
158.6 ± 3.5 (2300 ± 50)
137.9 ± 3.5 (2000 ± 50)
82.7 ± 3.5 (1200 ± 50)
67.2 ± 1.7 (975 ± 25)
41.4 ± 3.5 (600 ± 50)
55.2 ± 3.5 (800 ± 50)
82.7 ± 3.5 (1200 ± 50)
144.8 ± 3.5 (2100 ± 50)
127.6 ± 3.5 (1850 ± 50)
155.1 ± 1.7 (2250 ± 25)
103.4 ± 3.5 (1500 ± 50)
103.4 ± 3.5 (1500 ± 50)
93.9 ± 2.6 (1362 ± 38)
113.8 ± 3.5 (1650 ± 50)
86.2 ± 3.5 (1250 ± 50)
113.8 ± 3.5 (1650 ± 50)
86.2 ± 3.5 (1250 ± 50)
103.4 ± 3.5 (1500 ± 50)
117.2 ± 3.5 (1700 ± 50)
72.4 ± 3.5 (1050 ± 50)
93.1 ± 3.5 (1350 ± 50)
113.8 ± 3.5 (1650 ± 50)
44.8 ± 1.7 (650 ± 25)
127.6 ± 3.5 (1850 ± 50)
48.3 ± 3.5 (700 ± 50)
115.5 ± 3.5 (1675 ± 50)
115.5 ± 3.5 (1675 ± 50)
115.5 ± 3.5 (1675 ± 50)
113.8 ± 3.5 (1650 ± 50)
NOTE: If your product number is not listed, please contact MICO, Inc. for information.
TABLE 1 (Specications)
Figure 1b

MICO, Inc. (4) Form No. 81-463-003 Revised 2017-10-24
SERVICE INSTRUCTIONS
Disassembly
(Refer to Figure 2)
1. Remove plug (1) from housing (7). Remove o-ring (2) from
plug (1). NOTE: Plug (1) is under spring tension.
2. Remove spring (3) and rod (4) from housing (7).
3. Remove plug (8) from housing (7). Remove o-ring (2) from
plug (8).
4. Remove spool (6) from housing (7) through plug (1) end
ONLY. Remove quad ring (5) from spool (6).
5. Earlier Design: Loosen nut (9) on screw assembly (10) and
remove screw assembly (10) from housing (7). Remove o-ring
(11) from screw assembly (10). Remove spring (12), ball (13),
seat (14), o-ring (15), and washer (16) from housing (7).
Later Design: Some later designs use a directional spring
(12). Directional spring (12) is attached to screw assembly
(10) by means of the small diameter end of spring (12)
being snapped into a groove on the nose end of screw
assembly (10). See Figure 2b. Remove nut (9) and remove
screw assembly (10) from housing (7). Remove o-ring (11)
from screw assembly (10) from nut (9) side of screw assembly.
Remove shim (33), spring (12), steel ball (13), seat (14), o-ring
(15), and washer (16) from housing (7).
6. Remove lter (17) and washer (18) from housing (7).
7. Remove plug (32) from housing (7). Remove o-ring (15) from
plug (32).
8. BEFORE moving screw (30), ACCURATELY MEASURE ITS
DEPTH from the end of housing (7) and record for reassembly
purposes. Remove screw (30) from housing (7).
9. Remove spring (29), retainer (28), and ball (27). Be sure to
keep ball (27) separate from ball (22) for reassembling.
10. Remove pin (31) from screw (30) using a drive pin punch.
NOTE: Be careful not to damage threads.
11. Remove plug (19) from housing (7). Remove o-ring (15) from
plug (19). NOTE: Be careful not to damage threads.
12. Remove spring (20), stop (21), and ball (22) from housing (7).
13. Place housing (7) on bench with plug (19) end down. Spool
(23) may or may not fall out at this point.
14. Using a 6.3-7.9 mm (0.25-0.31 in) diameter wood or plastic
dowel, carefully remove insert (24) and spool (23) from hous-
ing (7). Insert (24) must come out plug (19) end of housing (7).
Be careful not to scratch or mar valve seats on insert (24).
15. Remove spool (23) from insert (24). Remove o-rings (25 & 26)
and back-up rings (34 & 35) from insert (24). NOTE: Back-up
rings (34 & 35) are only used in model 06-463-080.
Assembly
(Refer to Figure 2)
WASH ALL PARTS WITH CLEAN SOLVENT AND DRY. LUBRICATE
ALL RUBBER PARTS WITH CLEAN SYSTEM FLUID PRIOR TO
ASSEMBLY. BE SURE ENTIRE ASSEMBLY PROCEDURE IS
DONE WITH CONTAMINATION FREE METHODS.
1. Install new o-ring (2) on plug (8). Install plug (8) into housing
(7) and torque 122.0-135.6 N∙m (90-100 lb∙ft).
2. Install new quad ring (5) on spool (6). Be sure quad ring (5)
does not twist in groove.
3. Lubricate spool (6) with clean system uid and insert into
housing (7) as shown in Figure 2.
4. Install spring (3) and rod (4) into housing (7).
5. Install new o-ring (2) on plug (1). Install plug (1) into housing
(7) and torque 122.0-135.6 N∙m (90-100 lb∙ft).
6. Install new o-rings (25 & 26) and new back-up ring (34 & 35)
on insert (24) and install insert (24) into housing (7). Note
direction of assembly. Seat insert (24) with 12.7 mm (0.50 in)
diameter wood or plastic dowel. NOTE: Back-up rings (34 &
35) are only used in model 06-463-080 and are to be in-
stalled as shown in Figure 2a.
7. Install spool (23) into insert (24) in housing (7). Note direction
of spool (23), long shoulder end is up toward end plug (19),
see Figure 2a.
8. Install ball (22) on insert (24) in housing (7). Install stop (21)
over ball (22) and spring (20) over stop (21).
9. Install new o-ring (15) on plug (19) and carefully install into
housing (7), centering spring (20). Torque plug (19)
47.5-54.2 N∙m (35-40 lb∙ft).
10. Turn housing (7) so plug (8) is vertically upward. Install ball
(27) in housing (7). Be sure ball (27) is centered in bottom
of hole. Install retainer (28) and spring (29) into housing (7).
11. Insert new pin (31) in screw (30). Be sure pin (31) is aligned
properly and is evenly driven into screw (30). NOTE: Be
careful not to damage threads.
12. Thread screw (30) in housing (7) to the depth recorded during
disassembly.
13. Install new o-ring (15) on plug (32). Install plug (32) in housing
(7) and torque 47.5-54.2 N∙m (35-40 lb∙ft).
14. Install washer (18) and new lter (17) in housing (7).
15. Earlier Design: Install new o-ring (11) on screw assembly
(10). Install washer (16), new o-ring (15), seat (14), ball (13),
spring (12), and screw assembly (10) into housing (7). Torque
screw assembly (10) 24.4-29.8 N∙m (18-22 lb∙ft). Then install
nut (9) on screw assembly (10) and torque nut 43.4-51.5 N∙m
(32-38 lb∙ft).
Later Design: Some later designs use a directional spring
(12). Directional spring (12) is attached to screw assembly
(10) by means of the small diameter end of spring (12)
being snapped into a groove on the nose end of screw
assembly (10). If necessary, reattach the small diameter of
spring (12) into the groove on the nose end of screw
assembly (10) using a slight twisting motion. See Figure
2b. Install new o-ring (11) on screw assembly (10) from nut (9)
side of screw assembly. Install washer (16), new o-ring (15),
seat (14), steel ball (13), and spring (12) in housing (7). Fully
lubricate shim (33) with clean system uid and install in hous-
ing (7) on end of seat (14). Install screw assembly (10) in
housing (7). Torque screw assembly (10) 24.4-29.8 N∙m
(18-22 lb∙ft). Then install nut (9) on screw assembly (10) and
torque nut 43.4-51.5 N∙m (32-38 lb∙ft).
VALVE ADJUSTMENT
(Refer to Table 2)
1. See machine servicing instructions to properly reinstall accu-
mulator charging valve. Tee an accurate pressure gauge on
an accumulator line.
2. Start pump and allow approximately one minute for charging
to start (pressure in gauge will read accumulator precharge
plus). If valve does not begin to charge, stop the pump and
remove end plug (32) and turn screw (30) approximately 1/4
turn clockwise. Reinstall end plug (32). Check the high limit
specications (see TABLE 2). Repeat adjustment of screw (30)
as needed until the high limit setting is met. Pressure limits can
be checked correctly only if after each adjustment of screw
(30) the accumulator pressure is reduced below the low limit
setting and the system recharges the accumulator pressure to
its high limit. NOTE: Be sure to reinstall plug (32) before
starting pump.
3. Torque end plug (32) 47.5-54.2 N∙m (35-40 lb∙ft).
Be sure system energy is relieved from accumulator charge
valve before removing from machine. See machine service
manual for procedures to relieve system energy.
NOTE
Locate the model number on the accumulator charging valve and
compare it to the model number in TABLE 2. Be sure you have
the proper service instructions.
NOTE
Observe torque specications as indicated in assembly proce-
dures or system damage or failure may occur.
Do not exceed the high limit pressure setting indicated in TABLE
2 or system damage or failure may occur.

Form No. 81-463-003 Revised 2017-10-24 (5) MICO, Inc.
FIGURE 2
Figure 2a
Model
Number
Repair Kit
Number
Nominal
High Limit (cut out)
bar (PSI)
Nominal
Low Limit (cut in)
bar (PSI)
06-463-012
06-463-030
06-463-032
06-463-034
06-463-052
06-463-080
06-400-099
06-400-099
06-400-099
06-400-099
06-400-099
06-400-323
124.1 ± 3.5 (1800 ± 50)
75.8 ± 3.5 (1100 ± 50)
127.6 ± 3.5 (1850 ± 50)
151.7 ± 3.5 (2200 ± 50)
137.9 ± 3.5 (2000 ± 50)
170.0 ± 3.5 (2465 ± 50)
93.9 ± 2.6 (1362 ± 38)
55.2 ± 3.5 (800 ± 50)
103.4 ± 3.5 (1500 ± 50)
124.1 ± 3.5 (1800 ± 50)
113.8 ± 3.5 (1650 ± 50)
140.0 ± 3.5 (2030 ± 50)
NOTE: If your product number is not listed, please contact MICO, Inc. for information.
TABLE 2 (Specications)
Figure 2b
NOTE
Repair kit includes a plastic poppet
which is not used in these models.
Items included in Repair Kit
Included only in Repair Kit 06-400-323
●

MICO, Inc. (6) Form No. 81-463-003 Revised 2017-10-24
SERVICE INSTRUCTIONS
Disassembly
(Refer to Figure 3)
1. Remove plug (1) from housing (7). Remove o-ring (2) from
plug. NOTE: Plug is under spring tension.
2. Remove spring (3) and rod (4) from housing.
3. Remove plug (8) from housing. Remove o-ring (2) from plug
(8).
4. Remove spool (6) from housing through plug (1) end ONLY.
Remove quad ring (5) from spool (6).
5. Remove nut (9) and remove screw assembly (11) from hous-
ing (7). Remove o-ring (10) from screw assembly (11) from nut
(9) side of screw assembly. NOTE: Some later designs use a
directional spring (13). Directional spring (13) is attached
to screw assembly (11) by means of the small diameter
end of spring (13) being snapped into a groove on the
nose end of screw assembly (11). See Figure 3b.
6. Remove shim (12), spring (13), ball (14), seat (15), o-ring (16),
washer (17), lter (18), and washer (19) from housing (7).
7. Remove plug (33) from housing (7). Remove o-ring (16) from
plug (33).
8. See spring (30) note in Figure 3. Remove spacer (32), shim(s)
(31), spring (30), retainer (29), and ball (28) from housing (7).
Be sure to keep ball (28) separate from ball (23) for reassem-
bling. NOTE: Be aware of the number of shim(s) (31)
removed for reassembly purposes. See note for spring
(30).
9. Remove plug (20) from housing (7). Remove o-ring (16) from
plug (20).
10. Remove spring (21), stop (22), and ball (23) from housing (7).
11. Place housing (7) on bench with plug (20) end down. Spool
(24) may or may not fall out at this point.
12. Using a 6.3-7.9 mm (0.25-0.31 in) diameter wood or plastic
dowel, carefully remove insert (25) and spool (24) from hous-
ing (7). Insert (25) must come out plug (20) end of housing (7).
Be careful not to scratch or mar valve seats on insert (25).
13. Remove spool (24) from insert (25). Remove o-rings (26 & 27)
from insert (25).
Assembly
(Refer to Figure 3)
WASH ALL PARTS WITH CLEAN SOLVENT AND DRY. LUBRICATE
ALL RUBBER PARTS WITH CLEAN SYSTEM FLUID PRIOR TO
ASSEMBLY. BE SURE ENTIRE ASSEMBLY PROCEDURE IS
DONE WITH CONTAMINATION FREE METHODS.
1. Install new o-ring (2) on plug (8). Install plug (8) into housing
(7) and torque 122-135.6 N∙m (90-100 lb∙ft).
2. Install new quad ring (5) on spool (6). Be sure quad ring (5)
does not twist in groove.
3. Lubricate spool (6) with clean system uid and insert into
housing (7) as shown in Figure 3.
4. Install spring (3) and rod (4) into housing (7).
5. Install new o-ring (2) on plug (1). Install plug (1) into housing
(7) and torque 122.0-135.6 N∙m (90-100 lb∙ft).
6. Install new o-rings (26 & 27) on insert (25) and install insert
(25) into housing (7). Note direction of assembly. Seat insert
(25) with 12.7 mm (0.50 in) diameter wood or plastic dowel.
7. Install spool (24) into insert (25) in housing (7). Note direction
of spool (24), short shoulder end is up toward end plug (20),
see Figure 3a.
8. Install ball (23) on insert (25) in housing (7). Install stop (22)
over ball (23) and spring (21) over stop (22).
9. Install new o-ring (16) on plug (20) and carefully install into
housing (7), centering spring (21). Torque plug (20)
47.5-54.2 N∙m (35-40 lb∙ft).
10. Turn housing (7) so plug (8) is vertically upward. Install ball
(28) in housing (7). Be sure ball (28) is centered in bottom of
hole. Install retainer (29) and spring (30) into housing (7). Be
sure to install spring (30) as indicated by note in Figure 3.
11. Install shim(s) (31) on spacer (32) and install spacer (32) in
housing (7). Be sure to install the same number of shim(s)
(31) as were removed.
12. Install new o-ring (16) on plug (33). Install plug (33) in housing
(7) and torque 47.5-54.2 N∙m (35-40 lb∙ft).
13. Install new o-ring (10) on screw assembly (11). Install washer
(19), new lter (18), washer (17), new o-ring (16), seat (15),
ball (14), and spring (13) in housing (7). Fully lubricate shim
(12) with clean system type uid and install in housing (7) on
end of seat (15). Install screw assembly (11) in housing (7).
Torque screw assembly (11) 24.4-29.8 N∙m (18-22 lb∙ft). Then
install nut (9) on screw assembly (10) and torque nut
43.4-51.5 N∙m (32-38 lb∙ft). NOTE: Some later designs use a
directional spring (13). Directional spring (13) is attached
to screw assembly (11) by means of the small diameter
end of spring (13) being snapped into a groove on the
nose end of screw assembly (11). If necessary, reattach
the small diameter of spring (13) into the groove on the
nose end of screw assembly (11) using a slight twisting
motion. See Figure 3b.
14. See machine servicing instructions to properly reinstall
accumulator charging valve. Verify that the accumulator
charging valve is operating correctly. If accumulator charging
valve is inoperable, contact MICO, Inc.
Be sure system energy is relieved from accumulator charge
valve before removing from machine. See machine service
manual for procedures to relieve system energy.
NOTE
Locate the model number on the accumulator charging valve and
compare it to the model number in TABLE 3. Be sure you have
the proper service instructions.

Form No. 81-463-003 Revised 2017-10-24 (7) MICO, Inc.
FIGURE 3
Figure 3a
Model
Number
Repair Kit
Number
Nominal
High Limit (cut out)
bar (PSI)
Nominal
Low Limit (cut in)
bar (PSI)
06-463-072 06-400-099 58.6 ± 3.5 (850 ± 50) 37.9 ± 3.5 (550 ± 50)
NOTE: If your product number is not listed, please contact MICO, Inc. for information.
TABLE 3 (Specications)
Figure 3b
NOTE
Repair kit includes a plastic poppet
and plastic pin which are not used
in this model.
● Items included in Repair Kit

MICO, Inc. (8) Form No. 81-463-003 Revised 2017-10-24
SERVICE CHECKS FOR HYDRAULIC SYSTEMS
ACCUMULATOR CHARGING CYCLE
REPEATS FREQUENTLY WHEN ACCU-
MULATOR IS NOT NORMALLY BEING
DISCHARGED IN SERVICE
1. Leaking accumulator lines or ttings
1. Checklinesandttingsforleaks
and correct
2. Incorrect setting of accumulator
gas charge
2. Check accumulator gas charge
3. Line to accumulator plugged
3. Replace line
4. Inoperative charging valve
4. Replace charging valve
ACCUMULATOR STARTS TO CHARGE
BUT DOES NOT REACH HIGH LIMIT
1. No oil or low oil level in tank
1. Check oil level
2. Pump worn or inoperative and not
delivering full ow or pressure
2. Check pump
3. Inoperative system relief valve (valve
leaking or has low setting so full ow and
pressure are not available)
3. Check relief valve
4. Inoperative charging valve
4. Replace charging valve
ACCUMULATOR CHARGING TIME TOO
LONG
1. No oil or low oil level in tank
1. Check oil level
2. Relief valve setting too low
2. Check valve setting
3. Pump worn or inoperative and not
delivering full ow or pressure
3. Check pump
4. Inoperative charging valve
4. Replace charging valve
ACCUMULATOR FAILS TO START
CHARGING
1. No oil or low oil level in tank
1. Check oil level
2. Worn or defective pump
2. Checkpumppressureandow
3. Inoperative relief valve
3. Check relief valve setting
4. Air in accumulator line
4. Bleed accumulator line
5. Inoperative charging valve
5. Replace charging valve
VERY RAPID CYCLING OF CHARGING
VALVE
1. Incorrect setting of accumulator
gas charge
1. Check accumulator gas charge
2. Inoperative charging valve
2. Replace charging valve
LACK OF ADEQUATE FLOW THROUGH
VALVE
1. Inoperative pump
1. Check pump pressure and
delivery
2. Inoperative relief valve
2. Check relief valve setting
3. Blocked lines
3. Replace lines
4. Inoperative charging valve
4. Replace charging valve
SERVICE DIAGNOSIS
(Refer to Figures 1 and 2)
ACCUMULATOR CHARGING CYCLE
REPEATS FREQUENTLY WHEN ACCU-
MULATOR IS NOT NORMALLY BEING
DISCHARGED IN SERVICE
1. Poppet or ball (13) leaking.
2. O-ring (15) next to seat (14) leaking.
3. O-ring (25) leaking.
4. Ball (22) leaking.
5. Inoperative seat on insert (24).
ACCUMULATOR STARTS TO CHARGE
BUT DOES NOT REACH HIGH LIMIT
1. O-ring (26) leaking.
2. Quad ring (5) on spool (6) has
been damaged or worn.
ACCUMULATOR CHARGING TIME TOO
LONG
1. Dirt in lter (17).
2. Poppet or ball (13) stuck, partially closed.
3. Seat (14) partially plugged
ACCUMULATOR FAILS TO START
CHARGING
1. Broken spring (29).
2. Broken spring (3).
3. Quad ring (5) inoperative.
4. Spool (6) stuck.
5. Dirt in lter (17).
VERY RAPID CYCLING OF CHARGING
VALVE
1. Insert (24) worn.
SERVICE DIAGNOSIS
(Refer to Figure 3)
ACCUMULATOR CHARGING CYCLE
REPEATS FREQUENTLY WHEN ACCU-
MULATOR IS NOT NORMALLY BEING
DISCHARGED IN SERVICE
1. Ball (14) leaking.
2. O-ring (16) next to seat (15) leaking.
3. O-ring (26) leaking.
4. Ball (23) leaking.
5. Inoperative seat on insert (25).
ACCUMULATOR STARTS TO CHARGE
BUT DOES NOT REACH HIGH LIMIT
1. O-ring (27) leaking.
2. Quad ring (5) on spool (6) has been
damaged or worn.
ACCUMULATOR CHARGING TIME TOO
LONG
1. Dirt in lter (18).
2. Ball (14) stuck, partially closed.
3. Seat (15) partially plugged
ACCUMULATOR FAILS TO START
CHARGING
1. Broken spring (30).
2. Broken spring (3).
3. Quad ring (5) inoperative.
4. Spool (6) stuck.
5. Dirt in lter (18).
VERY RAPID CYCLING OF CHARGING
VALVE
1. Insert (25) worn.