8 307043
Air Motor Service
13. Straighten the lockwires (L*) and remove them
from the upper valve nuts (J*). Screw the upper
valve nuts off. Remove the trip rod yoke (O),
actuator (V), and trip rod (C).
14. Unscrew the bottom valve nuts (K*), and remove
the poppets (N*). Make sure the valve bar spring
clips (W) are not worn or damaged and that they
properly guide the actuator (V).
15. Remove the exhaust valve poppets (M) by cutting
them with a side cutter, then pull them out of the
actuator (V).
16. Remove piston o-ring (Z) and internal base o-ring
(15* or 19*). Inspect o-rings.
17. Clean all the parts carefully in a compatible solvent
and inspect them for wear or damage. Use all the
repair kit parts during reassembly, and replace
other parts as necessary.
18. Check the surfaces of the piston, piston rod, and
cylinder wall for scratches or wear. A scored rod
will cause premature packing wear and leaking.
Reassembly
1. Place the piston rod (A) flats in the vise with the air
motor up.
2. Pull the exhaust valve poppets (M*) into the valve
actuator (V), and clip off the top parts of the pop-
pets (shown with dotted lines in the Cutaway View
in Fig. 3).
3. Install the grommets (Y*) in the actuator (V), place
the inlet valve poppets (N*) in the piston, and
thread the bottom valve nuts (K*) onto the inlet
valve poppets until there are a few threads left
before the threads run out.
NOTE: If you thread the valve nuts too far down onto
the poppets, they will run off of the threaded part of the
poppets.
4. Place the actuator (V) in the yoke (O) and insert
the trip rod (C) through them. Thread a 5/16–18
unc nut on the trip rod to prevent it from sliding into
the piston when assembling. Grease the trip
rod/actuator/yoke assembly heavily and place into
the piston with the inlet valve poppets (N*) going
through the grommets (Y*).
5. Thread the top valve nuts (J*) onto the inlet valve
poppets (N*) until one thread of the inlet valve
poppets is exposed above the valve nuts.
Fig. 3
04118
COU L
J
X
G
F
T
T
04119
WV
G
MX
J
K
N
0.145 in.
(3.7 mm)
P
Q
S
R
Z
U
Y
Cutaway View
Cut off the tops of the poppets
as indicated by the dotted lines
Z
Insert Screw
Driver Here