308981 19
Service
Diaphragms (Husky 716)
NOTE:
Fluid Section Repair Kit D05XXX is available. See page 22 to order the correct kit for your pump. Parts included in
the kit are marked with a double dagger (
‡
) in
Fig. 10
and in the Parts Drawings and Lists. General purpose grease
111920 and Adhesive 113500 are supplied in the kit. Service the diaphragms as follows. See
Fig. 10
.
Disassembly
1. Relieve the pressure. See
Pressure
Relief Procedure
on page 10.
2.
Remove the manifolds (102) and fluid covers (101).
NOTE:
Make sure all the check valve parts stay in
place. See
Fig. 8
.
3.
Remove the grounding strip from the vee clamps
(109), and remove the vee clamps.
4.
Remove one of the fluid-side diaphragm plates
(133) (whichever one comes loose first when you
use a wrench on the hex of each), and pull the
diaphragm shaft out of the center housing (11).
Overmolded Diaphragms
: Grip both diaphragms
securely around the outer edge and rotate counter-
clockwise. One diaphragm assembly will come free
and the other will remain attached to the diaphragm
shaft (15). Remove the freed diaphragm and the air
side plate (6). Pull the other diaphragm assembly and
the diaphragm shaft (15) out of the center housing
(11).
5.
Use a wrench on the flats of the diaphragm shaft
(15) to remove the other fluid-side diaphragm plate
(133) from the diaphragm shaft.
Overmolded Diaphragms
: Use a wrench on the
flats of the diaphragm shaft (15) to remove the
second diaphragm from the diaphragm shaft.
6.
Remove the screws (141) and air covers (136), and
remove all old gasket (12) material from the ends of
the center housing (11) and the surfaces of the air
covers.
7.
Remove the diaphragm shaft u-cups (416) and pilot
pin o-rings (1).
8.
Inspect all parts for wear or damage, and replace as
necessary.
Reassembly
1.
Insert a diaphragm shaft u-cup (416) and a pilot pin
o-ring (1) into the end of the diaphragm shaft bore of
the center housing (11).
NOTE:
Make sure the lips of the u-cup face out of
the center housing.
2.
Line up the holes in the gasket (12) with the holes in
the end of the center housing (11), and use six
screws (141) to fasten an air cover (136) to the end
of the center housing (11). Torque the screws to 35
to 45 in-lb (4.0 to 5.1 N-m).
3.
Position the exhaust cover (13) and o-ring (4) on the
center housing (11).
4.
Repeat steps 1 and 2 for the other end of the center
housing and the remaining air cover.
5.
Apply medium-strength (blue) thread locker to the
threads of the screws (140). Install on one and of
the diaphragm shaft (15) the following parts (see
proper order in
Fig. 10
): air-side diaphragm plate
(6), backup diaphragm (402, used only on models
with PTFE diaphragms), diaphragm (401), fluid-side
diaphragm plate (133), o-ring (115), and screw
(140).
NOTE:
The words “AIR SIDE” on the diaphragm
(401), the backup diaphragm (402, used only on
models with PTFE diaphragms), and the flat side of
the air-side diaphragm plate (6) must face toward
the diaphragm shaft (15).
Overmolded Diaphragms
: Assemble the air-side
plate (6) onto the diaphragm (401). The words AIR
SIDE on the air side plate must face away from the
diaphragm. Apply medium-strength (blue) thread
locking adhesive to the threads of the diaphragm
assembly. Screw the assembly into the diaphragm
shaft (15) hand tight.
