Removal of the Oxygen-System Test Port

TASK 35-13-41-000-801-A
Removal of the Oxygen-System Test Port

WARNING: CLEAN THE TOOLS AND MAKE SURE YOUR HANDS ARE CLEAN TO PREVENT CONTAMINATION OF THE OXYGEN SYSTEM.

WARNING: KEEP ALL HYDROCARBONS (FUELS, LUBRICANTS, ETC.) AWAY FROM ALL SOURCE OF OXYGEN. OXYGEN BECOMES EXPLOSIVE WHEN IT TOUCHES HYDROCARBONS.

ZONE: 125
FIN: 5755HM ** ON A/C NOT FOR ALL

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 2M (6 FT)
No specific	AR	BAG - VINYL
No specific	1	PIN DRIFT
No specific	1	PLUG - BLANKING, APPROVED FOR USE WITH OXYGEN
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
125	LATERAL AVIONIC COMPARTMENT
812

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 35-00-00-860-001-A	Special Precautions When Working on a Gaseous Oxygen System
Oxygen-System Test Port

3. Job Set-up
Subtask 35-13-41-860-050-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(2) Put a WARNING NOTICE(S) in position in the cockpit to tell persons not to operate the crew oxygen system.
(3) Obey the special precautions when you do work on a gaseous oxygen system (Ref. AMM TASK 35-00-00-860-001).

Subtask 35-13-41-010-050-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Put the ACCESS PLATFORM 2M (6 FT) in position at access door 812.
(2) Open access door 812.
(3) Get access to the avionics compartment.
(4) Close the valve of the oxygen storage cylinder (5750HM).
(5) Put a WARNING NOTICE(S) to tell persons not to open the valve of the oxygen storage cylinder (5750HM).

Subtask 35-13-41-865-050-A ** ON A/C NOT FOR ALL

C. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	OXYGEN/CREW/OXY/SPLY	1HT	HA01

Subtask 35-13-41-870-050-A ** ON A/C NOT FOR ALL

D. Bleeding of the Crew Oxygen System
(1) In the cockpit, on the overhead control and indicator panel 21VU, push the OXYGEN/CREW SUPPLY pushbutton switch (the OFF legend goes off).
(2) On an oxygen-mask stowage box, push and hold the PRESS TO TEST AND RESET control button and at the same time, push and hold the PRESS TO TEST/EMERGENCY knob on the mask regulator until the system is empty.
(3) On the overhead control and indicator panel 21VU, release the OXYGEN/CREW SUPPLY pushbutton switch (the OFF legend comes on).

4. Procedure
Subtask 35-13-41-020-050-A ** ON A/C NOT FOR ALL

A. Removal of the Oxygen-System Test Port

CAUTION: PUT DRY AND CLEAN METAL OR PLASTIC PLUGS ON ALL PIPES OR UNITS THAT YOU REMOVE TEMPORARILY. THEN PUT EACH PIPE OR UNIT IN A SEALED VINYL BAG. IF YOU DO NOT OBEY THESE INSTRUCTIONS, CONTAMINATION OF THE OXYGEN SYSTEM CAN OCCUR.

(1) Loosen the nut (4) and disconnect the pipe (3).
(2) Put the PLUG - BLANKING, APPROVED FOR USE WITH OXYGEN on all the disconnected line ends.
(3) Remove the coupling (7).
(a) Turn the coupling (7) counterclockwise to remove it.
(4) Put the coupling (7) into a BAG - VINYL.
(5) Remove the filter (6) from the fitting (5) with a PIN DRIFT.
(6) Discard the filter (6).
(7) Remove the screws (1), nuts (2) and fitting (5).
(8) Put the fitting (5) into a BAG - VINYL.

[Rev.10 from 2021] 2026.04.01 01:04:40 UTC