4-20. Port Retainer Maintenance - continued.
Repair is limited to the replacement of damaged parts.
(1) Lubricate new preformed packing (9) with silicone lubricant and install in the helmet shell.
(2) Place face port (7) into helmet shell. Ensure packing (9) is properly seated under the face port.
(3) Lubricate new preformed packing (8) with silicone lubricant and install on the rear of port retainer (6).
(4) Align port retainer holes with holes in helmet shell.
(5) Install whisker exhaust (para 4-18). Do not tighten screws.
(6) Place a liberal amount of sealing compound on the rear mount surface of the handle (2) and in the
mount screw hole of the helmet. Set the handle in place and run in the front mount screws (1) until
snug, but not tight. Hold the handle to avoid leverage on the front screws while starting the rear
mount washer (4) and screw (3) in place. Make the screw snug but not tight.
(7) Install retaining screws (5). Do not tighten.
(8) Slightly tighten center screw at top of port retainer, followed by screws on each side of nose clearing
device. Slightly tighten screw next to side block assembly and then the screw opposite it. Slightly
tighten remaining screw.
(9) Starting with top screw and working in a clockwise direction around the retainer, slightly tighten
screws with torque wrench until screws are torqued to 12 in.-lb.
(10) Tighten the rear handle mount screw and immediately wipe up any excess sealing compound.
(11) Install nose clearing device (para 4-17).