Removing And Installing A Pump - Graco ULTRA 500 231-032 Instructions-Parts List Manual

PISTON
ASSEMBLY
42
224
43
41
Fig 38–2
Remove the pump
See Fig 38–2.
1. Flush the pump. Relieve pressure. Stop the pump
with the piston rod (224) in its lowest position or care-
fully rotate the blades of the fan with a screwdriver to
lower the rod.
2. While holding the pump intake valve (223) steady
with a wrench, unscrew the suction tube (61).
3. Disconnect the hose (68).
4. Push the retaining spring (42) up. Push out the pin
(43).
5. Loosen the locknut (41) and unscrew the pump from
the bearing housing (73).
Install the pump
See Fig 38–3.
1. Screw the displacement pump 3/4 of the way into the
bearing housing (73).
2. Hold the pin (43) up to the pin hole in the connecting
rod assembly (70) and continue screwing in the
pump until the pin slides easily into the hole. Back off
the pump until the top threads of the pump cylinder
are flush with the face of the bearing housing and the
outlet nipple (39) is straight back.
307–758
38
DISPLACEMENT PUMP REPAIR
219
218
TAPERED END

REMOVING AND INSTALLING A PUMP

73
216
68
39
223
61
12. Slide the sleeve/piston rod assembly INTO THE
BOTTOM OF THE CYLINDER. This is to prevent
packing damage during reassembly. See Fig 38–1.
13. Screw down the cylinder locknut (41) until it is finger
tight at the bottom of the external cylinder threads.
14. Place the flats of the intake valve (223) in a vise. In-
stall a new o-ring (202*). Screw the pump cylinder
into the valve. Torque to 67 ft-lb (90 N.m). See Fig
37–3.
15. Install the pump.
3. Push the retaining spring (42) into the groove all the
way around the connecting rod.
4. Tighten the locknut (41) very tight–about 70 ft-lb (97
N.m)–with a 2 in. open–end wrench and a light ham-
mer.
WARNING
Be sure the retaining spring (42) is firmly in the
groove of the connecting rod, all the way around, to
prevent it from working loose due to vibration. Refer
to Fig 38–3.
If the pin works loose, 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, sprayer damage or property damage.
CAUTION
If the locknut (41) loosens during operation, the
threads of the bearing housing (73) will be dam-
aged. Be sure to tighten the locknut firmly.
5. Tighten the packing nut (216) just enough to stop
leakage, but no tighter. Fill the wet-cup/packing nut
1/3 full with Graco TSL. See Fig 38–2.
70
FACE OF
BEARING
HOUSING
41
TORQUE TO
70 ft–lb
(95 N.m)
Fig 38–3
43
42
73