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308981
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
and in the Parts Drawings and Lists. General purpose grease 111920 and Adhe-
sive 113500 are supplied in the kit. Service the diaphragms as follows. See
Disassembly
Relieve the pressure. See
1. Remove the manifolds (102) and fluid covers (101).
NOTE:
Make sure all the check valve parts stay in
.
2. Remove the grounding strip from the vee clamps
(109), and remove the vee clamps.
3. 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 counterclock-
wise. 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).
4. 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 dia-
phragm from the diaphragm shaft.
5. 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.
6. Remove the diaphragm shaft u-cups (416) and pilot
pin o-rings (1).
7. 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
): air-side diaphragm plate (6), backup
diaphragm (402, used only on models with PTFE dia-
phragms), 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 dia-
phragm 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.
6. Put grease on the diaphragm shaft (15), and carefully
(do not damage the shaft u-cups) run the diaphragm
shaft (15) through the center housing (11) bore.
7. Repeat step 5 for the other end of the diaphragm
shaft (15), and torque the diaphragm shaft screws
(140) to 80 to 90 in-lb (9 to 10 N-m) at 100 rpm
maximum.
Overmolded Diaphragms
: Repeat Step 5 for the other
end of the diaphragm shaft (15).
8. Install the muffler (3).
NOTE:
When you install the vee clamps in step 9, orient
the center housing (11) so the air inlet is approximately
45° above horizontal and the muffler (3) is
approximately horizontal.
9. Apply thin, even film of grease to inside of vee clamp
(109).
10. Position the fluid covers (101), install the vee clamps
(109) around the fluid and air covers, install the
grounding strip on the vee clamps, and torque the vee
clamp nuts to 80 to 90 in-lb (9 to 10 N-m). See
11. Make sure all the check valve parts are in place. See
12. Install the manifolds (102), and torque the manifold
bolts (105) to 80 to 90 in-lb (9 to 10 N-m). See
