TM 5-4220-225-14
Table 2-2. Mission Predive Setup Procedure (Cont).
Step
Procedure
NOTE
If handle is loose, tighten the friction drag screws
until the desired action is achieved.
(12) Rotate valve handle.Motion should be firm and have some
resistance but operate smoothly through full range,
approximately three turns.
(13) Depress the chin button with finger pressure. Motion should be
smooth with spring pressure increasing steadily. Upon releasing
finger pressure, the valve should shut with spring tension.
d.
Ambient Exhaust Valve Check.
(1)
Remove the adjustable exhaust valve cover and inspect the
valve body for dirt, corrosion, and damage. Inspect the diffuser
for dirt or damage.Replace or clean parts as necessary
(2)
Remove the diaphragm retainer and inspect the diaphragm for
damage and deterioration.
(3)
Apply a light film of lubricant to the bead of the diaphragm and
install the diaphragm and ambient diaphragm retainer. Ensure
the diaphragm seats properly.
(4)
Install the ambient exhaust valve cover.
e.
Air Adapter Assembly Check.
(1)
Remove the air adapter cap and filter screen. Inspect the
adapter, screen, and cap for dirt, corrosion, and damage.
Ensure the nonreturn valve is properly installed. (Do not remove
the valve unless it is suspect.) Reinstall screen.
(2)
Visually inspect for loose or missing screws. Tighten or replace
as required.
f.
Air Supply Whip.
(1)
Remove the protective caps from the air supply whip and
inspect the air supply whip fittings for corrosion and damage.
Inspect the gasket for wear or deterioration and lubricate lightly
with an approved lubricant.
Replace the gasket if required.
(2)
Install the whip to the helmet air adapter. Ensure it is right.
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