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 S 014-030
 (3)  Open the access panels to the oxygen cylinders.
 S 864-028
 CAUTION: DO NOT TIGHTEN THE SHUTOFF VALVE ON EACH OXYGEN CYLINDER MORE
_______ THAN 25 POUND-INCHES. THIS CAN CAUSE DAMAGE TO THE SHUTOFF VALVE.
 (4)  Close the shutoff valve on each oxygen cylinder slowly.
 NOTE: The shutoff valve can be tightened by hand which is
____
 equivalent to 25 pound-inches.

 S 034-005
 (5)  
Disconnect the electrical connector on the pressure reducer.

 S 034-006

 (6)  
Remove the coupling assembly

 WARNING:_______LOOSEN THE COUPLING NUT CAREFULLY. IF NOT, THE REMAINING OXYGEN CAN RELEASE WITH A LARGE FORCE AND CAUSE THE TEMPERATURE TO INCREASE. THIS CAN START AN IGNITION WITH THE OXYGEN AND CAUSE INJURY TO PERSONS AND DAMAGE TO THE AIRPLANE AND EQUIPMENT.
 (a)  
Slowly and continuously loosen the coupling nut between the oxygen cylinder and coupling assembly to decrease line pressure.

 (b)  
Disconnect the coupling assembly from the oxygen cylinder.

 (c)  
Disconnect the outlet B-nut on the pressure reducer.

 (d)  
Support the assembly, which includes the coupling assembly and pressure transducer (with the pressure reducer attached).

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 (e)  
Remove the assembly.

 (f)  
Remove the coupling assembly.

 S 034-007
 (7)  
Install the protective caps or plugs to the open lines, fittings or the ports to prevent contamination of the system.

 S 024-008

 (8)  
Remove the pressure reducer.

 (a)  
Remove the union from the end on the medium pressure of the pressure reducer.

 (b)  
Remove the metal seal between the fitting and the pressure reducer.

 NOTE: Save the serviceable seal and the fitting for
____
 installation.

 CAUTION: YOU MUST USE A WRENCH ON THE LEG FLATS OF THE COUPLING
_______ ASSEMBLY WHEN YOU TURN THE PRESSURE REDUCER FREE. IF YOU DO NOT THE COUPLING ASSEMBLY CAN BREAK.
 (c)  
Remove the union between the pressure reducer and the coupling assembly from the high pressure end.

 (d)  
Remove the metal seal between pressure reducer and coupling assembly.

 NOTE: Keep the serviceable seal and the fitting for
____
 installation.

 TASK 35-21-12-404-009
 3. Pressure Reducer Installation (Fig. 401)
_____________________________
 A. Consumable Materials
 (1)  
G00091 Compound - Oxygen System Leak Detection (MIL-L-25567)

 (2)  
G00713 Cloth - Clean, Dry, Lint-Free, White, Cotton

 B. References
 (1)  
AMM 24-22-00/201, Manual Control

 (2)  
AMM 35-00-00/201, Oxygen

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MAINTENANCE MANUAL

 (3)  
AMM 35-21-00/501, Oxygen System

 (4)  
IPC 35-21-12

 (5)  
SSM 35-11-01

 (6)  
WDM 35-11-13

 C. Access
 (1)  Location Zone 124 Forward Cargo Container Compartment, Aft Half Right
 D. Procedure
 S 914-023
　
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