12
307962
Displacement Pump Service
WARNING
To reduce the risk of static arcing which could
result in a fire or explosion and serious injury, use
only non-sparking tools if the pump is being as-
sembled or worked on in a hazardous atmosphere.
WARNING
To reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure
on page 6.
NOTE:
A displacement pump repair kit, part no.
224902, is available. Use all the parts in the kit
for the best results.
1.
Relieve the pressure
.
2.
Lay the pump on a work table.
3.
Hammer off the upper lug nut (2). Grasp the outlet
housing (10) and pull the displacement pump down
until the pin (4) is exposed. Push out the pin.
4.
Clamp the intake housing (19) in a vise. Hammer off
the lower lug nut (21). Disassemble the intake valve.
Inspect the seat in the intake housing (19) for pitting
or gouging that would prevent the ball from seating
properly and replace the part if necessary. Replace
the ball (18) and o–ring (20*).
5.
Tap the displacement rod (3) assembly out the bot-
tom of the pump.
6.
Clamp the piston housing (13) in a padded vise. Use
a wrench on the flats to unscrew the piston seat (22).
Remove the lower u-cup packing (15*), spacer (27),
and the ball (14).
7.
Using wrenches on the flats, unscrew the piston rod
(12) from the displacement rod (5).
8.
Remove the throat packings (8* and 25*), washer
(24*) and nut (9).
9.
Inspect the cylinders (6 and 11) and the outlet hous-
ing (10) for wear or damage. Disassemble these
parts only if they are being replaced, and then re-
place the o–rings (23* and 20*), also.
10. Clean all parts thoroughly and inspect for wear or
damage. Replace parts as needed.
11. Reassemble the pump in the reverse order of disas-
sembly. Be sure the nut (9) is turned down to the bot-
tom thread of the piston rod (12), before installing the
washer and throat packings.
1
01606
17
21
1
2
6
9
23*
25*
12
16
20*
18
3
11
13
22
19
24*
10
4
14
*8
Fig 5
5
*20
15*
27
Apply Lubricant
Torque to 35–50 ft–lb.
Bottom nut on thread of rod.
Torque piston seat to housing to 15 to 20 ft-lb.
6
5
7
8
Apply Lubricant
Torque to 130–150 in–lb.
4
Torque rod to housing to 130–150 in–lb.
3
Apply thread sealant.
2
8
1
4
8
1
5
1
7
1
5
5
7
3
3
1
6
5
1
8
2
5
