Graco Husky 1040, Instructions-Parts List Manual

Page: 21 / 36

308443 21
Reassembly – Overmolded Diaphragms
WARNING
1. Lubricate and install the shaft u-cup packings (402*)
so the lips face out of the housing (1). See Fig. 13.
2. Assemble the air side plate(104) onto the
diaphragm (403). The wide, radiused side of the
plate must face the diaphragm. Apply
medium-strength (blue) Loctite
® or equivalent to the
threads of the diaphragm assembly. Screw the
assembly into the shaft (24) hand-tight.
3. Grease the length and ends of the diaphragm shaft
(24). Insert the shaft/diaphragm assembly into one
side of the pump. Align the fluid cover (101) and the
center housing (1) so the arrow (A) faces the same
direction as the air valve. Secure the cover with the
screws (107 and 108), handtight.
4. Torque the longer screws (106) oppositely and
evenly to 130 to 150 in-lb (14 to 17 N-m), using a
13mm socket wrench. Then torque the shorter
screws (112). See
Torque Sequence , page 32.
5. Assemble the other diaphragm assembly to the
shaft as explained in step 2. This diaphragm will be
lifted off the air cover at this point.
6. Supply the pump with low pressure air (less than 7
psi [0.05 MPa, 0.5 bar]). The diaphragm will very
slowly pull onto the air cover. Find the pressure that
keeps the diaphragm close enough to the secure
with the screws, but does not let it contact the pilot
pin.
NOTE: Do not deform the diaphragm manually. The
diaphragm needs uniform pressure to deform properly
for maximum life.
7. Align the fluid cover (101) and the center housing
(1) so the arrow (A) faces the same direction as the
air valve. Secure the cover with two of the longer
screws (108), handtight.
NOTE: If the diaphragm contacts the pilot pin and is
forced away from the air cover, try Step 5 again. If
necessary, return to Step 3.
8. Torque the longer screws (106) oppositely and
evenly to 130 to 150 in-lb (14 to 17 N-m), using a
13mm socket wrench. Then torque the shorter
screws (112). See
Torque Sequence , page 32.
9. Assemble the ball check valves and manifolds as
explained on page 18
To reduce the risk of serious injury, including
amputation, do not put your fingers or hand between
the air cover and the diaphragm.