TM 5-3805-280-24-2
Hydraulic System
1--Pilot Cap
18--Housing--4-Spool
33--Special Cap Screw (4
48--Spring
2--Cap Screw (14 used)
19--O-Ring (3 used)
used)
49--O-Ring
3--Boom Reduced
20--O-Ring (4 used)
34--Spring Seat (8 used)
50--Backup Ring
Leakage Valve Housing
21--Pilot Cap
35--Spring (4 used)
51--O-Ring
4--Cap Screw (2 used)
22--Boom Down Circuit
36--Arm II Spool
52--Spacer
5--O-Ring
Relief and
37--Poppet
53--Bucket Curl Circuit
6--Plug
Anti-Cavitation Valve
38--Spring
Relief and
7--Lock Nut
23--Right Propel Spool
39--O-Ring
Anti-Cavitation Valve
8--Boom Manual Lower
24--Bucket Spool
40--Backup Ring
54--Bucket Dump Circuit
Screw
25--Boom I Spool
41--Plug
Relief and
9--O-Ring
26--Backup Ring
42--Boom Reduced
Anti-Cavitation Valve
10--Plug
27--Plug
Leakage Check Valve
55--Boom Up Circuit Relief
11--Plug
28--O-Ring
Poppet
and Anti-Cavitation
12--Spool
29--Spring
43--Spring
Valve
13--Spring Seat
30--Washer
44--O-Ring
14--Spring
31--Sleeve
45--Backup Ring
15--O-Ring
32--Boom Down
46--Spacer
16--Spacer
Regenerative Valve
47--Arm Regenerative
17--O-Ring
Poppet
Check Valve Poppet
breakdown the high strength thread lock and
IMPORTANT: Spools (23--25 and 36) are select
sealer. Hold spool in a vise using wooden blocks
fitted to bores in housing and are a
to protect it.
different design for each function.
Spools must be installed into the
Apply thread lock and sealer (high strength) to
same bores from which they were
threads of plugs (27 and 41). Tighten plugs. Hold
removed for proper operation.
spool in a vise using wooden blocks to protect it.
NOTE: The letters, A--F, are used in the illustration to
Boom Regenerative Valve-to-Control Valve Spool Plug--
indicate the location of parts in housing.
Specification
15. Circuit relief and anti-cavitation valve (22, 53,
Torque.................................................................... 15 Nm (130 lb-in.)
54 and 55): Disassemble valves for cleaning and
inspection only. Valves are serviced as
17. Boom reduced leakage valve: Pull spacer (46)
assemblies.
from housing using a M5-0.8 cap screw.
Tighten valve into housing.
Tighten reduced leakage valve housing-to-housing
cap screws.
Circuit Relief and Anti-Cavitation Valve-to-Housing--
Specification
Boom Reduced Leakage Valve Housing-to-Housing Cap
Screw--Specification
Torque....................................................................... 83 Nm (62 lb-ft)
Torque....................................................................... 78 Nm (58 lb-ft)
Check and adjust pressure setting after assembly.
(See Circuit Relief Valve Test and Adjustment in
Tighten plug (11) into housing.
Group 9025-25.)
16. Boom regenerative valve: Heat plugs (27 and
33
41) in boom I spool (25) using a heat gun to
3360
109
Continued on next page
TX,33,UU4003
1921SEP9814/17
21-141
