Service
Repairing the Air Valve
Tools Required
DTorque wrench
DTorx (T20) screwdriver or 7 mm (9/32 in.) socket wrench
D
D
DLithium base grease
NOTE: Air Valve Repair Kits 236273 (aluminum center housing models) and 255061 (sst center housing models) are available. Refer to page 23. Parts included in the kit are marked with a symbol, for example (4{H). Use all the parts in the kit for the best results.
Disassembly
WARNING
To reduce the risk of serious injury whenever you are instructed to relieve pressure, always follow the Pressure Relief Procedure on page 10.
1. | Relieve the pressure. |
2. | With a Torx (T20) screwdriver or 7 mm (9/32 in.) |
| socket wrench, remove the six screws (3), air |
| valve cover (2), and gasket (4). See Fig. 6. |
3. | Move the valve carriage (5) to the center position |
3 2 2
4{H
1
Muffler not included on
1 Model No. 253485
Torque to
2
03268B
Fig. 6
1 | See Detail at right. | 5 |
and pull it out of the cavity. Remove the valve |
block (7{H) and |
Using a |
straight up and out of the cavity. See Fig. 7. |
4. Pull the two actuator pistons (11) out of the bear- |
ings (12). Remove the |
the pistons. Pull the pilot pins (16) out of the |
bearings (15). Remove the |
pilot pins. See Fig. 8. |
5. Inspect the valve plate (8H) in place. If damaged, |
use a Torx (T20) screwdriver or 7 mm (9/32 in.) |
socket wrench to remove the three screws (3). |
Remove the valve plate (8H) and, on aluminum |
center housing models only, remove the seal (9). |
See Fig. 9. |
6. Inspect the bearings (12, 15) in place. See Fig. 8. |
The bearings are tapered and, if damaged, must |
be removed from the outside. This requires disas- |
sembly of the fluid section. See page 20. |
7. Clean all parts and inspect for wear or damage. |
Replace as needed. Reassemble as explained on |
2Grease.
3 Grease lower face.
2 {H6
3 {H7
18{H 3 | 5 1 |
11
page 15.
14 308441
Fig. 7
03269