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33 - 8
Boom Arm Anti-drift Valve
Dismantling the Boom /Dipper Anti-drift Valve
1
Loosen the plug assembly (14) and remove the O-ring.
2
Remove the piston (4), the spool (5) and the spring (7).
3
Carefully loosen the plug (3) and remove the O-ring (13).
Care must be taken to avoid components being
propelled out of the valve by the remaining inner
pressure.
4
Remove the sleeve (16) and the poppet (2). Remove the
O-rings (9, 10) on the sleeve and the back-up rings (11,
12).
5
Remove the spring seat (16) and the spring (8) from the
spring groove.
6
Loosen the socket head bolts (42) and remove the body
(51-1) from the main body. Remove the O-rings (15) on
the mating face.
7
Remove the spacer (55) from the valve housing. remove
the O-ring (56) and the back up ring (57).
8
Remove the spring (54) and the poppet (53).
Cleaning / Inspection
1
Clean the dismantled parts with a coating of clean oil.
2
Dry with compressed air. Place each part on a clean
sheet of paper or vinyl for inspection.
3
Verify that all sliding parts move easily.
4
Replace the springs if they are damaged, deformed or
worn.
5
Replace all used O-rings and back-up rings with new
before assembly.
6
Check that there is no foreign matter in any passages or
grooves.
Assembling the Boom/Dipper Anti-Drift Valve
1
Install the O-rings (9, 10) and the back-up rings (11, 12)
to the outside groove of the sleeve (6).
2
Insert the poppet (2) and the spool (5) into the sleeve
socket.
3
Apply grease to the components. Install the spring (8)
and the spring seat (16) on the smaller end of the
poppet. Compress the spring, spring seat and sleeve
into the body socket (1).
4
Install the spring (7) and the piston (4) on the plug (51-3)
5
Tighten the plug assembly (14) with the O-ring installed
on the plug (3).
Torque tighten to 69 - 78 Nm (50.8 - 57.5 lbf ft).
6
Tighten the plug assembly (51-13) with the O-ring
installed on the body (1).
Torque tighten to 69 - 78 Nm (50.8 - 57.5 lbf ft).
7
Install the O-ring (15) to the groove on the mating face
with the body.
Section E
Hydraulics
9803/6020
Section E
33 - 8
Issue 1
Control Valve
Summary of Contents for JS70
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