Graco EM 490 Instructions-Parts List Manual page 19

WARNING
To reduce the risk of serious bodily injury, including
fluid injection; splashing in the eyes; injury from mov-
ing parts or electric shock, follow the Pressure Re-
lief Procedure Warning on page 11 before continu-
ing.
Removing the Pump.
1 Flush the sprayer. Relieve pressure.
2 Hold the intake valve (223) steady with a wrench and
unscrew the inlet tube (29).
3 Unscrew the hose (52) from the pump nipple (10).
4 Use a screwdriver to push the retaining spring (33)
aside, and then push out the pin (34).
5 Loosen the locknut (112) and unscrew the pump (58).
A
33
36
34
224
112
TORQUE
TO
96 N.M
(70 FT–LB)
58
29
Fig 22
Reinstalling the Pump.
1 Rotate the crankshaft (A) so the pump coupling (36)
is in its lowest position. (Rotate the fan blades at the
rear of the motor with a screwdriver to rotate the
crankshaft.) The pump piston rod (224) should pro-
trude about 25 mm (1 in.) above the pump cylinder.
Insert the pump into the pump coupling (36) until the
pin holes are aligned. Insert the pin (34). Position the
spring (33) so it covers the ends of the pin. Screw the
pump into the drive housing (55) until it stops at the
locknut (112). Unscrew the pump just until the fitting
(10) faces straight back.
DISPLACEMENT PUMP
See Fig 22.
219
220
221*
204*
52
202*
10
223
TORQUE TO
64 N.M
(48 FT–LB)
See Fig 22.
Be sure the retaining spring (33) is firmly and
completely in the groove of the connecting rod to
prevent the pin (34) from working loose due to
vibration. See Fig 22.
If the pin works loose, it or other parts could break
off due to the force of the pumping action. These
parts could be projected through the air and result
in serious bodily injury or property damage, in-
cluding damage to the pump, connecting rod or
bearing housing.
2 Torque the locknut (112) to 96 N.m (70 ft–lb).
3 Reassemble the remaining parts, in the reverse order
of removal.
Disassembly
1 Remove and disassemble the intake valve (223). If no
further service is needed, reassemble the valve, us-
ing a new gasket (202*). Torque to 64 N.m (48 ft–lb).
See Fig 22.
2 Remove the packing nut (216) and plug (205).
3 Tap the piston rod (224) down with a plastic mallet.
Pull the rod out of the bottom of the cylinder (219).
4 Remove the packings and glands from the throat of
the cylinder (219).
NOTE: Whenever you disassemble the pump for clean-
ing or repair, remove the sleeve. Use the special
tool, p/n 222–585. See ACCESSORIES, page
27 to order it.
Always use the special sleeve removal tool to re-
move the sleeve. Other removal methods could
cause the pump to rupture, resulting in serious
bodily injury. If the sleeve cannot be removed easily
using the tool, return the sleeve and cylinder to your
Graco distributor for removal.
5 Screw the large nut (A) of the tool into the top of the
cylinder (219). Screw down the rod (B) to push the
sleeve out. Remove the tool. See Fig 23.
0081
Fig 23
6 Clamp the flats of the piston rod (224) in a vise. Un-
screw the retaining nut (21 1). Unscrew the piston
valve (222) from the rod. Remove all parts from the
piston. See Fig 24.
WARNING
WARNING
B
A
219
0028