Troubleshooting guide
Air
Motor and Throat Service
WARNING
MOVING
P
ARTS HAZARD
T
o reduce the risk of pinching or ampu
-
tating your fingers,
always
keep fingers
clear of the toggle assemblies (M).
8.
Use a screwdriver to push down on the trip rod
yoke (24) and snap the toggles down. See Fig. 5.
Remove the lockwires (32) from the adjusting nuts
(30) of the transfer valves. Screw the top nuts of
f.
Screw the stems (42) out of the grommets (28)
and bottom nuts (30). T
ake the valve poppets (49)
of
f the stems and squeeze them firmly to check for
cracks.
9.
Grip the toggle rockers (26) with a pliers. Com
-
press the springs (27) and swing the toggle as
-
sembly (M) up and away from the piston lugs (L),
and remove the parts. Check that the valve actua
-
tor (33) is supported by the spring clips (55), but
slides easily into them. See Fig. 5.
10.
Remove the trip rod yoke (24), actuator (33) and
trip rod (51). Check the exhaust valve poppets (50)
for cracks.
NOTE: T
o remove the exhaust valve poppets (50),
stretch them out and cut them with a sharp knife.
11.
Remove one of the air motor muf
fler plates (17 or
41). Pull the piston up out of the base. Remove the
throat packing nut (38) and packing (46).
Reassembly
1.
Clean all the parts carefully in a compatible solvent
and inspect for wear or damage. Use all the repair
kit parts during reassembly and replace other parts
as necessary
.
2.
Check the polished surfaces of the piston, piston
rod and cylinder wall for scratches or wear
. A
scored rod will cause premature packing wear and
leaking.
3.
Lubricate all parts with a light, waterproof grease.
4.
Install the packing (46
), with the lips facing down.
Screw the packing nut (38) into the base (52)
loosely
. See Fig. 6.
5.
Slide the piston rod (44) down through the pack
-
ings and lower the piston (56) into the base (52).
Be sure the o-rings (34*,36, 37*) are in place.
6.
Pull the exhaust valve poppets (50*) into the valve
actuator (33) and clip of
f the top part shown with
dotted lines. See Fig. 5.
7.
Install the transfer valve grommets (28*), then re
-
assemble the valve mechanism. Before installing
the lockwires (32*) in the adjusting nuts (30*), use
the special gauge 171–818 to adjust the transfer
valve so there is 0.145 in. (3.7 mm) clearance be
-
tween the poppets (49*) and the seat when it is
open. See Fig. 5. Snap the toggles (35) to the up
position.
8.
Reassemble the air motor and assemble to the
displacement pump. Before installing the air motor
plate, tighten the throat packing nut (38) just snug
–– do not overtighten.
9.
Before remounting the pump, connect an air hose
and run the pump slowly [at about 40 psi (3 bar)]
to see that it operates smoothly
.
10.
Reconnect the ground wire before regular opera
-
tion of the pump.