16
308443
Service
Repairing the Air Valve
Tools Required
•
Torque wrench
•
Torx (T20) screwdriver or 7 mm (9/32”) socket
wrench
•
Needle-nose pliers
•
O-ring pick
•
Lithium base grease
NOTE:
Air Valve Repair Kit 236273 (aluminum center
housing models) and 255061 (sst center housing
models) are available. Refer to page 29. Parts included
in the kit are marked with a symbol, for example (4
).
Use all the parts in the kit for the best results.
Disassembly
WARNING
1. Relieve the pressure.
2. With a Torx (T20) screwdriver or 7 mm (9/32”)
socket wrench, remove the six screws (3), air valve
cover (2), and gasket (4). See Fig. 7.
3. Move the valve carriage (5) to the center position
and pull it out of the cavity. Remove the valve block
(7
) and o-ring (6
) from the carriage. Using a
needle-nose pliers, pull the pilot block (18) straight
up and out of the cavity. See Fig. 8.
4. Pull the two actuator pistons (11) out of the bearings
(12). Remove the u-cup packings (10) from the
pistons. Pull the pilot pins (16) out of the bearings
(15). Remove the o-rings (17) from the push pins.
See Fig. 9.
5. Inspect the valve plate (8) in place. If damaged, use
a Torx (T20) screwdriver or 7 mm (9/32”) socket
wrench to remove the three screws (3). Remove the
valve plate (8) and on aluminum center housing
models only, remove the seal (9). See Fig. 10.
6. Inspect the bearings (12, 15) in place. See Fig. 9.
The bearings are tapered and, if damaged, must be
removed from the outside. This requires
disassembly of the fluid section. See page 23.
7. Clean all parts and inspect for wear or damage.
Replace as needed. Reassemble as explained on
page 17.
Torque to 50–60 in-lb
(5.6–6.8 N-m).
2
3
2
4
2
See Detail at right.
1
Grease.
2
Grease lower face.
3
18
5
11
1
3
2
5
6
7
3
Fig. 7
Fig. 8
To reduce the risk of serious injury whenever you are
instructed to relieve pressure, always follow the
