10
8. Tap the air inlet plate (37) with a plastic mallet to help
align the screw holes of the plate and pump housing
(2). Install a screw (35) and washer (36) to check the
alignment; adjust as necessary . Loosely install a
screw and washer in the opposite corner. Then install
the remaining screws and washers. Using an oppo-
site and alternate pattern, torque the screws evenly
to 8.5–9.5 N.m (6.2–7 ft–lb).
Replacing a Diaphragm (See Fig. 6)
NOTE:
Diaphragm Repair Kits are available for each of
the diaphragm materials. Refer to the parts list
for your pump.
To convert a buna–N, polyester elastomer , or
EPDM diaphragm pump to a
Model, or-
der
Conversion Kit 222–373. Refer to the
parts list for your pump.
1. Remove the pump from its mounting.
2. Remove the bolts (14), washers (16) and nuts (15)
from the outlet manifold (20).
3. Tap the manifold with a plastic mallet to free it from
the pump. Remove all four o–rings (17), the valve
seat plates (18) and the balls (19, or 57 on Models
218–940 and 220–434).
4. Turn the pump over. Repeat as in steps 2 and 3 for
the inlet manifold (21).
5. Remove the bolts (14, 3, or 55), legs (12 or 13),
washers (16) and nuts (15) from the diaphragm cov-
ers (11) on each side of the pump.
6. Hold the fluid side support plate (8) on one end of the
pump and loosen and remove the plate (8) on the
other end of the pump. Remove the diaphragm (7),
backup diaphragm (53, Models 220–545 and
220–546 only), air side support plate (6) and stop (5).
NOTE:
The diaphragm shaft (1) does not have to be re-
moved from the pump housing when replacing a
diaphragm.
CAUTION
Never try to pull the diaphragm shaft (1) through
the pump unless the air director valve assembly
has been removed. If you do, the actuator pin (27)
in the air director valve assembly will be damaged.
Fig. 6
12
11
1
4
51
2
15 16
40
20
14
17*
19* or 57*
18
17*
14
13
12
15
16
6
4 5
16
15
35
36
21
14
16
17*
18
19*
17*
16
15
CHAMFERED
SIDE FACES
BALL
TORQUE TO
27 N.m
(20 ft–lb)
TORQUE TO
8.5–9.5 N.m
(6.2–7 ft–lb)
TORQUE TO
13.5–16 N.m
(9.8–12 ft–lb)
TORQUE TO
42–47 N.m
(30–35 ft–lb)
TORQUE TO
13.5–16 N.m
(9.8–12 ft–lb)
TORQUE TO
27 N.m
(20 ft–lb)
13
16
51
CHAMFERED
SIDE FACES
BALL
3 (or 55 on Models
220–545 and 220–546)
(3 on Models
220–545 and
220–546)
TORQUE TO
27 N.m
(20 ft–lb)
53 (Models
220–545 and
220–546 Only)
7
FLUID
OUTLET
FLUID
INLET
52
8
PTFE
PTFE
