819.4496
23
Service
Bearing and Air Gasket Removal
Tools Required
•
Torque wrench
•
10 mm socket wrench
•
Bearing puller
•
O-ring pick
•
Press, or block and mallet
Disassembly
NOTE: Do not remove undamaged bearings.
1.
Relieve the pressure.
2.
Remove the manifolds and disassemble the ball check
valves as explained on page 18.
3.
Remove the fluid covers and diaphragm assemblies as
explained on page 19.
NOTE: If you are removing only the diaphragm shaft bearing
(19), skip step 4.
4.
Disassemble the air valve as explained on page 16.
5.
Using a 10 mm socket wrench, remove the screws (25)
holding the air covers (23) to the center housing (1). See
F
6.
Remove the air cover gaskets (22). Always replace the
gaskets with new ones.
7.
Use a bearing puller to remove the diaphragm shaft
bearings (19), air valve bearings (12) or pilot pin
bearings (15). Do not remove undamaged bearings.
8.
If you removed the diaphragm shaft bearings (19), reach
into the center housing (1) with an o-ring pick and hook
the u-cup packings (402), then pull them out of the
housing. Inspect the packings. See F
Reassembly
1.
If removed, install the shaft u-cup packings (402*) so the
lips face out of the housing (1).
2.
The bearings (19, 12, and 15) are tapered and can only
be installed one way. Insert the bearings into the center
housing (1), tapered end first. Using a press or a block
and rubber mallet, press-fit the bearing so it is flush with
the surface of the center housing.
3.
Reassemble the air valve as explained on page 17.
4.
Align the new air cover gasket (22) so the pilot pin (16)
protruding from the center housing (1) fits through the
proper hole (H) in the gasket.
5.
Align the air cover (23) so the pilot pin (16) fits in the middle
hole (M) of the three small holes near the center of the
cover. Install the screws (25), handtight. See
Fig. 14. Using
a 10 mm socket wrench, torque the screws oppositely
and evenly to 15–17 N•m.
6.
Install the diaphragm assemblies and fluid covers as
explained on page 19.
7.
Reassemble the ball check valves and manifolds as
explained on page 18.
Warning
To reduce the risk of serious injury whenever you are
instructed to relieve pressure, always follow the Pressure
Relief Procedure on page 13.
