TM 10-7310-241-12&P Change 1 4-12 4-12.  REPAIR OF COVER ASSEMBLY FOR MODEL RAK-15 (Continued) d.  Testing of Pressure Relief Valve.            (1)  Place the pressure relief valve (5) on a clean, flat  surface with the flange (8) uppermost and verify             that the valve stem (9) is level with the inward gauze filter (10).        (2)  Using a suitable tool (e.g., ballpoint pen top), carefully depress the valve stem (9) to its full extent and      verify that it moves freely with no binding of the internal spring.      (3)  Release the valve stem (9) and verify that it returns to a position level with the inward gauze filter (10).      (4)  Hand-hold the pressure relief valve (5) and place the base (11) firmly against the mouth.         (5)  Blow sharply through the outward gauze filter (12) and verify that the valve operates with a clearly              audible sound.      (6)  Verify that the valve stem (9) has returned to a position level with the inward gauze filter (10). e.  Installation of Pressure Relief Valve.          (1)  Check valve recess (6) is clean and the small steam hole at the bottom is not blocked.      (2)  Install preformed packing (7) in the valve recess (6) and ensure that it is correctly positioned.      (3)  Install pressure relief valve (5) in the valve recess (6) and rotate with downwards pressure to ensure               that it is correctly positioned.      (4)  Install the valve retaining plate (3) in the cover (4) and ensure that it is correctly positioned. CAUTION DAMAGE TO SCREW.  In step (5), use standard hand tools to install the screw (1) and only tighten with sufficient torque to ensure that the valve retaining plate (3) is held firmly in position.  The application of excessive torque can result in damage to the screw (1).       (5)  Ensure that the screw hole is correctly aligned then install lock washers (2) and install and tighten               screws (1).       (6)  Install the cover (Subparagraph 2-9a, steps (8) and (9)). 4-12.1  REPLACEMENT OF THE COVER ASSEMBLY FOR MODEL 471012 This task covers:     a.    Removing the Lid. b.    Installing the Lid. c.    Testing the Pressure Relief Valve. d.    Serving the Pressure Relief Valve. e.    Replacing the Pressure Relief Valve. f.     Installing the Pressure Relief Valve. g.    Removing the Lid Gasket. h. Installing the Lid Gasket. i.    Servicing the Lid.