VERDER VERDERAIR VA 25 Instructions-Parts List Manual page 18

Service
4. Unscrew one outer plate (105) from the diaphragm
shaft (24). Remove one diaphragm (401), and the inner
plate (104). See Fig. 13.
NOTE: PTFE models include a PTFE diaphragm (403) in
addition to the backup diaphragm (401).
5. Pull the other diaphragm assembly and the diaphragm
shaft (24) out of the center housing (1). Hold the shaft
flats with a 19 mm open–end wrench, and remove the
outer plate (105) from the shaft. Disassemble the re-
maining diaphragm assembly.
6. Inspect the diaphragm shaft (24) for wear or scratches. If
it is damaged, inspect the bearings (19) in place. If the
bearings are damaged, refer to page 20.
7. 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. This can be done with the bearings (19) in
place.
8. Clean all parts and inspect for wear or damage. Replace
parts as needed.
18 819.4367
Reassembly
1. Grease the shaft u-cup packings (402*) and install them
so the lips face out of the housing (1). See Fig. 13.
2. Grease the length and ends of the diaphragm shaft (24),
and slide it through the housing (1).
3. Assemble the inner diaphragm plates (104), dia-
phragms (401*), PTFE diaphragms (403*, if present),
and outer diaphragm plates (105) exactly as shown in
Fig. 13. These parts must be assembled correctly.
4. Apply medium strength (blue) LoctiteR or equivalent to
the threads of the fluid-side plates (105). Hold one of the
outer plates (105) with a wrench, and torque the other
outer plate to 27 to 34 NSm at 100 rpm max. Do not over-
torque.
5. Align the fluid covers (101) and the center housing (1) so
the arrows (A) on the covers face the same direction as
the air valve (B). Secure the covers with the screws (106
and 112), handtight. Place the bolt caps (113*) on the
longer screws (106), and install the longer screws in the
top and bottom holes of the covers. See Fig. 12.
6. First, torque the longer screws (106) oppositely and
evenly to 14 to 17 NSm, using a 10 mm socket wrench.
Then torque the shorter screws (112). See Torque Se-
quence, page 30.
7. Reassemble the ball check valves and manifolds as ex-
plained on page 16.