Place an O-ring
on the packing nut
Screw the packing nut into the pump housing
NOTE:
Lubricate the parts with
a
lightweight oil
17.
Place the packings, one
at
a
time, into the packing
nut
in the following order: the u-cup packing
with the lips of the u-cup packing facing down
in the packing nut,
and then two back-up washers
(105).
before assembling.
18.
Loosely install the wet-cup packing nut
and
the wet-cup into the pump housing
19.
Install the packings on the piston in the following
order, (see Fig
one u-cup packing
with the
lips facing down, one back-up washer
the
seal spacer
the other back-up washer
the other u-cup packing
with the lips facing
up, and the back-up washer
See
Install the piston ball
in the piston valve
ing
Apply medium grade thread sealant to the
threads of the piston valve
Screw the piston
valve into the piston valve housing, torquing to
81-102
ft-lb). Screw the piston rod
into the piston valve, aiigning the holes. Insert the
cotter pin
-
1 30
Fig
4
21.
Place the pump housing
in the vise. Install
a
the pump cylinder
and slide
it
into the pump
new O-ring
in the pump housing. Lubricate
housing. Install the other O-ring
NOTE:
In the
ratio pumps, install the pump
cylinder
so
the tapered end faces the bottom
of
the pump.
22.
Install the displacement rod assembly through the
bottom of the pump, guiding
it
carefully through
the throat packings.
23.
Install a new u-cup packing
intake
cylinder's packing housing (REF
117)
so
the lips of
the
face up. Install the packing nut
and
torque to
34-47
ft-lb). Slide the valve
packing housing assembly, nut first, onto the
piston rod
24.
Place a new O-ring
around the intake cylinder
and screw the cylinder into the pump housing
torquing to
129-149
ft-lb).
25.
Thread the nut
onto the bottom of the piston
rod. Install the valve plate
valve guide
priming piston
and the other nut
26. Holding both nuts
with a wrench, torque the
bottom nut to
54-81
ft-lb).
27.
Tighten the packing nut
Torque the wet-cup
nut
to
54-81
ft-lb).
28.
Reconnect the displacement pump
to the air
motor
Refill the wet-cup
Reconnect the
ground wire to
motor if
it
was disconnected
during service.
Packing Periodic Replacement
'CAUTION
ment of the throat packings, in addition to the
oackina
is
essential.
packings to wear
more quickly, and costly damage to the displace-
ment rod may result from scoring.
mine how
need to change the
Check the throat packings weekly until you deter-
packings to reduce' displacement rod
Good oackinas should not have any cracks,
I
Order two washers (part no.
and one pecking
(part no.
178-9571.
To
change the throat packings:
1.
Unscrew the coupling nut
Remove the cotter
pin
loosen the jam nut and unscrew
con-
necting rod
See
breaks or
spots.
I
2.
Remove the wet-cup
Unscrew the packing
nut
from the cylinder nut
Unscrew the
wet-cup nut
from the packing nut
See
3.
Remove the packings and clean
all parts. Grease
the new packing and washers. Install the u-cup
packing
(1061
with the
facing down,
end then
two back-up washers
in the packing nut
See Fig
4.
Screw the wet-cup nut
into the packing nut
sure the O-ring
is in place in the wet-cup nut
and torque
it
to
(40-60
ft-lb).
Be
then continue reassembling the pump.
See
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