Repair - Graco EM 490R EM 490 Instructions-Parts List Manual

Reassembly Procedure
1. Stack the backup washer (219*), U–cup seal (205*)
lips down , and female gland (220*), alternate the
polyethylene and leather v–packings (217*, 218*) lips
up, and stack the male gland (213*) one at a time onto
the piston valve (224). See Fig 15.
2. Tighten the packing retaining nut (214) onto the piston
valve (224) and torque to 3–4 in–lb (0.34 – 0.35 N.m).
See Fig 13.
NOTE: NOTE THE ALIGNMENT of the piston (224) to
the nut (214). Maintain this alignment through-
out Steps 2, 3 and 4.
214
TORQUE NUT TO
3–4 IN-LB
(0.34–0.35 N.M)
Fig 13
3. Apply 1 drop only of sealant, supplied with the repair
kit, to the piston valve threads. Place the small ball
(203*) on the valve. See Fig 13. Hand tighten the
valve into the rod (223) just until the nut contacts the
rod. Place the flats of the displacement rod in a vise.
TORQUE NUT AGAINST ROD
TO 19 FT-LB (25 N.M)
DO NOT ALLOW THIS NUT TO
MOVE RELATIVE TO THE
PISTON (224) WHEN
INSTALLING PISTON ONTO ROD
Fig 14
4. Torque the nut (214) against the rod (223) to 19 ft–lb
(25 N.m). Use two wrenches to maintain the align-
ment as mentioned in the NOTE. See Fig 14.
5. Stack the male gland (211*), alternate the polyethyl-
ene and leather v–packings (218*, 209*) lips down
and stack the female gland (212*) one at a time into
the top of the cylinder. See Fig 15.
6. Loosely install the packing nut (221) and plug (201).
7. Insert the oiled piston rod (223) into the bottom of the
cylinder.
DISPLACEMENT PUMP
203*
APPLY ONE DROP
OF SEALANT TO
THESE THREADS
NOTE AND MAINTAIN
THIS ALIGNMENT
THROUGHOUT STEPS
3,4, AND 5
224
223
214
8. Assemble the intake valve. Use a new gasket (206*).
Screw the valve into the cylinder and tighten to 80 ft–
lb (107 N.m). See Fig 15.
9. Screw down the cylinder locknut (112) until it is finger
tight at the bottom of the external cylinder threads.
See Fig 15.
10. Install the displacement pump on the sprayer. See
page 16.
223
201
221
*212
*209
Lips must
face down
216
214
*208
Lips must face up
*205
Lips of seal
must face down
224
*207
215
*204
*206
Fig 15
112
218*
Lips must
face down
211*
203*
APPLY 1 DROP
OF ADHESIVE
(in repair kit)
TO THESE
THREADS
213*
217*
Lips must
face up
220*
219*
222
TORQUE TO
80 ft–lb
(107 N.m)