Refer to figure 1-26.
Loosen and remove the nut.
Pull out the valve from the hole in the base.
If the O-ring does not come off with the valve, remove the
Place the O-ring inside the collar of the valve.
Screw nut onto the valve barrel.
3-34. Optical Shroud and Window Assembly removal/replacement.
Refer to figure 1-27.
Use an orangewood stick to gently pry and lift off the
Gently scrape away any leftover rubber
Never use cleaning materials in a closed, or
poorly aired work area or near a fire or open
flame. Avoid touching skin with cleaning fluid.