Diaphragms And Center Section - Graco Husky 3300 Repair Parts

Repair

Diaphragms and Center Section

Disassembly
NOTE: Diaphragm kits are available in a range of mate-
rials and styles. See page 35 to order the correct dia-
phragms for your pump. A Center Rebuild Kit also is
available. See page 29. Parts included in the Center
Rebuild Kit are marked with an *. For best results, use
all kit parts.
1. Follow the Pressure Relief Procedure on page 10.
2. Remove the manifolds and disassemble the ball
check valves as explained on page 12.
NOTE: You may wish to remove the inner fluid cover
bolts (37) as you remove each manifold, for conve-
nience.
3. Overmolded Diaphragms
a. Orient the pump so one of the fluid covers faces
up. Use a 3/4 in. (19 mm) socket wrench to
remove the fluid cover bolts (36, 37), then pull
the fluid cover (2) up off the pump.
b. The exposed diaphragm (20) will screw off by
hand. The shaft will either release and come off
with this diaphragm, or remain attached to the
other diaphragm. If the diaphragm shaft bolt
(16) remains attached to the shaft (108),
remove it. Remove the air side diaphragm plate
(14) and washer (18).
c. Turn the pump over and remove the other fluid
cover. Remove the diaphragm (and the shaft, if
necessary).
d. If the shaft is still attached to either diaphragm,
grasp the diaphragm firmly and use a wrench
on the flats of the shaft to remove. Also remove
the air side diaphragm plate (14) and washer
(18). Continue with Step 5.
4. All Other Diaphragms
a. Orient the pump so one of the fluid covers faces
up. Use a 3/4 in. (19 mm) socket wrench to
remove the fluid cover screws (36, 37), then pull
the fluid cover (2) up off the pump. Turn the
pump over and remove the other fluid cover.
14
(PO and CO models)
b. Plastic Pumps: Hold the hex of one fluid side
diaphragm plate (15) with a 1-5/8 socket or box
end wrench. Use another wrench (same size)
on the hex of the other plate to remove. Then
remove all parts of the diaphragm assembly.
See F . 6.
IG
Metal Pumps: Turn the pump on its side. Hold
one diaphragm shaft bolt (16) with a wrench,
then use a 15/16 socket to remove the other
bolt. Remove all parts of the diaphragm assem-
bly. See F . 6, page 17.
IG
c. Disassemble the other diaphragm assembly.
5. Use an o-ring pick to remove the u-cup packings
(101) from the center housing. Bearings (109) can
remain in place.
6. If necessary, use a socket wrench to remove the
pilot valves (110).
Air Covers
Remove air covers only if a serious air leak suggests
that the gaskets need to be replaced.
1. Remove pilot valves (110).
2. Use a 3/8 allen wrench (aluminum) or a 5/8 socket
(polypropylene) to remove two bolts (103), then
remove one air cover (105). Repeat for the other air
cover.
3. Remove and replace the gasket (107).
4. Inspect the diaphragm shaft (108) for wear or
scratches. If it is damaged, inspect the bearings
(109) in place. If they are damaged, use a bearing
puller to remove them.
NOTE: Do not remove undamaged bearings.
3A0411A