Graco GM 3500 Instructions-Parts List Manual page 20

Installing the pump.
22
21
FACE OF
BEARING
HOUSING
Fig 19–4
1. Screw the pump 3/4 of the way into the bearing hous-
ing (21). Hold the pin (25) up to the pin hole in the con-
necting rod (22) and continue screwing in the pump
until the pin slides easily into the hole.
WARNING
To reduce the risk of serious bodily injury, always fol-
low the Pressure Relief Procedure Warning on
page 13 before repairing the sprayer.
NOTE: Steps 1 to 13 refer to Fig 20–1.
1. Remove the pump. See page 18.
2. Remove the four screws (73) and lockwashers (74)
from the bearing housing (21).
3. While pulling the connecting rod assembly (22) with
one hand, lightly tap the lower rear of the bearing
housing (21) with a plastic mallet to loosen it from the
drive housing (20). Pull the bearing housing and the
connecting rod assembly off the drive housing.
4. Inspect the crank (A) for excessive wear and replace
parts as needed.
5. Evenly lubricate the inside of the bronze bearing (C)
in the bearing housing (21), and the inside of the con-
necting rod link (D), with high–quality motor oil. Liber-
ally pack the roller bearing (E) in the connecting rod
assembly (22) with bearing grease.
6. Assemble the connecting rod (22) and bearing hous-
ing (21).
7. Clean the mating surfaces of the bearing and drive
housings.
8. Align the connecting rod with the crank (A). Align the
locating pins (F) in the drive housing (20) with the
holes in the bearing housing (21). Push the bearing
housing onto the drive housing or tap it into place with
a plastic mallet.
CAUTION
Use only the locating pins (F) to align or seat the
bearing housing (21) with the drive housing (20).
DISPLACEMENT PUMP
25
26
27
TORQUE:
70 ft–lb
(90 N.m)
BEARING HOUSING & CONNECTING ROD
2. Align the top threads of the pump cylinder flush with
the face of the bearing housing and so the outlet nip-
ple (57) is straight back.
3. Push the retaining spring (26) into the groove of the
connecting rod, all the way around. Tighten the lock-
nut (27) very tight – 70 ft–lb (95 N.m).
WARNING
Seat the retaining spring (26) firmly in the conecting
rod groove to prevent the pin (25) from working
loose due to vibration.
If the pin works loose, it or other parts could break
off due to the force of the pump action. These parts
could be projected through the air and result in seri-
ous injury or property damage, including the con-
necting rod and bearing housing.
4. Tighten the packing nut (216) only enough to stop
leaking. Fill the nut 1/2 full with Graco TSL.
5. Assemble the remaining parts.
9. Install the screws (73) and lockwashers (74) on the
bearing housing. Tighten the screws evenly to 175 in–
lb (20 N.m).
10. Install the pump. See above.
E
D
22
C
73,74
Torque to
175 in–lb
(20 N.m)
68
26
25
27
28
30
Fig 20–1
20
11
A
F
24
21
59
57
101
102
103