Troubleshooting guide

14
306-518
Displacement Pump Service
Disassembly
NOTE: Displacement Pump Repair Kit 237–498 in -
cludes repair parts for the pump piston and throat.
Parts included in the kit are marked with two asterisks,
for example, (6  ), in the text and drawings.
1. Flush the pump. Follow the Pressure Relief Pro -
cedure on page 9, before proceeding.
2. Disconnect the hoses, remove the pump from its
mounting, and clamp the air motor base in a vise.
3. Unscrew the intake valve body (61 or 65) from the
displacement cylinder (16). Disassemble the intake
valve (see the parts drawing for your model for
parts). Clean and inspect the parts for wear or
damage, and replace parts as needed. Be sure to
check the o-ring (60). Unless further service is
needed, reassemble and reinstall the intake valve,
using liquid sealant on the male threads. See
Fig. 6.
Fig. 6
45
31
36
34*
37*
44
52
16
15
61 or 65
15
2
11
3
19
18
12
13
6
12
18
19
10
38
46
60
9
DET AIL A
Throat Packings
DET AIL B
Piston Packings
56
04121
04122
04120
1
3
4
2
5
6
Lips must face down.
T orque to 95–105 ft-lb (129–142 N.m).
0.2 in. (5 mm) of ball travel.
See Detail A.
See Detail B.
Lips must face up.
4
2
3
5
1
6
1
CAUTION: T o avoid seal damage during installation, insert
seal at an angle as shown above, so that side A is below
hole C. Then press side B down until seal bottoms out.
C
A
B
Shows seal being installed.
04173
6
1