TM 5-4310-393-14
a. Remove the tube nuts, tubes and ferrules from the tube connections (Figure 410, Item 18) to the
valve head (19)
b.
Unscrew and remove the socket head cap screws (15)
c. Lift the valve head off the piston cylinder.
d.
Unscrew the valve cover (23) from the bottom of the valve head (19) using the valve wrench
B.
Replace
1.
Reassembly of the 2nd Stage Valve Head and Valves
a. To reassemble the valve head and valves, refer to figure 4-10 and proceed as follows.
b.
Before fitting the inlet valve to the valve head, grease the Inlet valve plate (12) slightly and place it
correctly on the valve seat to make reassembly easier.
c. After having assembled the inlet valve, peen the valve head twice, once on each side of the valve, to
lock the threads in place.
d. Apply a temperature-resistant, non-age-hardening RTV sealing compound to the sealing surface of
the valve head.
e. Torque the valve head cap screws (15) to 18 ft-lb (25 Nm) in accordance with the sequence shown in
Appendix G before tightening the socket set screw (5) in order to avoid damage to the valve body (10)
f.
Tighten the socket set screw (5) with the appropriate size Hex head wrench
g.
Position the gasket (4) and plain cap nut (3) and tighten it with an open end wrench
h.
Reinstall the tube connections (18) to the valve head (19).
4-23
