TM 5-4220-225-14
5-8.
Viewport Assemblies (Cont).
b.
Replace (Side). (figure 5-6)
NOTE
There is a right side viewport and a left side viewport, the procedures are the same for
both.
(1)
Remove eight screws (1), viewport retainer (2), viewport (3), and preformed packing (4).
(2)
Inspect viewport retainer (2) and replace if cracked or warped.
(3)
Inspect helmet shell (5) around viewport (3) and replace if shell is cracked.
(4)
Apply a thin film of lubricant to new preformed packing (4).
(5)
Ensure preformed packing groove is clean.
(6)
Install new preformed packing (4) in groove.
(7)
Install viewport (3) and ensure new preformed packing (4) stays in groove.
(8)
Install retainer (2) and four corner screws (1) finger tight.
(9)
Install remaining four screws (1) finger tight.
(10)
Torque all screws (1) to 8-10 in.-lb (0.9-1.2 Nm) .
(11)
Ensure new preformed packing (4) has not extruded.
5-14
