### Commercial **Airplanes** 

# 737 Service Bulletin **ALERT Number: 737-35A1121**  Original Issue: December 14, 2009 Revision 1: November 07, 2011 ATA System: 3512 **SUBJECT:** OXYGEN - Crew Oxygen System - Crew Oxygen Mask Stowage Box Unit - Inspect/Replace Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15 CFR 730-774). An export license may be required before it is used for development, production or use by foreign persons from specific countries. The controller of this data has the individual responsibility to abide by all export laws. 9E991 ECCN: 

## BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET Copyright © 2009 The Boeing Company Unpublished Work - All Rights Reserved Boeing claims copyright in each page of this document only to the extent that the page contains copyrightable subject matter. Boeing also claims copyright in this document as a compilation and/or collective work. This document includes proprietary information owned by The Boeing Company and/or one or more third parties. Treatment of the document and the information it contains is governed by contract with Boeing. For more information, contact The Boeing Company, P.O. Box 3707, Seattle, Washington 98124. Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner, BBJ, DC-8, DC-9, DC-10, KC-10, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8A, Poseidon and the Boeing livery are all trademarks owned by The Boeing Company; and no trademark license is granted in connection with this document unless provided in writing by Boeing.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 1 of 69 6.0BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 2 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT**

BLANK PAGE**Table of Contents** Revision Transmittal Sheet............................................ 5 Summary...................................................... 7 1. PLANNING INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 A. Effectivity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1. Airplanes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2. Spares Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 B. Concurrent Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 C. Reason. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 D. Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 E. Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 F. Approval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 G. Manpower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 H. Weight and Balance Changes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 I. Electrical Load Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 J. References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 1. Existing Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2. Data supplied with this Service Bulletin. . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3. Installation Drawings Used in the Preparation of this Service Bulletin. . . . . . . . . . . . 20 K. Publications Affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 L. Interchangeability and Intermixability of Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . 20 2. MATERIAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 A. Material - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 B. Industry Support Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 C. Parts Necessary For Each Airplane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 1. Kits/Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 2. Parts and Materials Supplied by the Operator. . . . . . . . . . . . . . . . . . . . . . . . 21 3. Parts Modified and Reidentified. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 4. Parts Removed and Not Replaced. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 D. Parts Necessary to Change Spares. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 E. Special Tooling - Price and Availability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 F. Special Tooling Necessary to do this Service Bulletin. . . . . . . . . . . . . . . . . . . . . . . 26 3. ACCOMPLISHMENT INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 A. GENERAL INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 B. WORK INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 FIGURE 1: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION [Group 1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 FIGURE 2: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION [Group 2]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 FIGURE 3: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION [Group 3]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 FIGURE 4: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION [Group 4]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 FIGURE 5: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION [Group 5]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 FIGURE 6: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION [Group 6]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 3 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT**FIGURE 7: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION [Group 7] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 FIGURE 8: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION [Group 8]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 FIGURE 9: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT [Group 1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 FIGURE 10: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT [Group 2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 FIGURE 11: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT [Group 3]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 FIGURE 12: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT [Group 4] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 FIGURE 13: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT [Group 5] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 FIGURE 14: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT [Group 6]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 FIGURE 15: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT [Group 7] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 FIGURE 16: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT [Group 8]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 4 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT**

### Commercial **Airplanes** 

# 737 Service Bulletin **ALERT Revision Transmittal Sheet**  **Number: 737-35A1121** Original Issue: December 14, 2009 Revision 1: November 07, 2011 ATA System: 3512 **SUBJECT:** OXYGEN - Crew Oxygen System - Crew Oxygen Mask Stowage Box Unit - Inspect/Replace This revision includes all pages of the service bulletin. **COMPLIANCE INFORMATION RELATED TO THIS REVISION** More work is necessary on airplanes inspected in accordance with the original issue of this service bulletin that did not have affected serial numbers. Verify maintenance inspection records or re-inspect the crew oxygen mask stowage box units in accordance with Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175 R02. More work is necessary on the airplanes inspected in accordance with the original issue of this service bulletin that have changed crew oxygen mask stowage box units. Re-inspect in accordance with Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175 R02. **REASON FOR REVISION** As a part of a service bulletin validation program, the service bulletin inspection was completed on a MXP147-2 crew oxygen mask stowage box by Service Bulletin 737-35A1121 R0 and MXP1/4-35-175 R0. The validation airplane is not part of the service bulletin effectivity however it was selected to demonstrate the inspection procedure only. Revision 1 is sent to perform a General Visual Inspection for affected serial numbers in accordance with revision 02 of Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175 and change the serial number of inspected crew oxygen mask stowage box units. This revision is sent to make the changes below: 1. Replaced reference to Intertechnique (Avox-Eros Services, INC) Service Bulletin MXP1/4-35-175, Rev 0 with reference to Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175, Rev 02. 2. Summary: – Compliance: Added FAA Notice of Proposed Rule Making 2010-NM-094-AD. – Industry Support Information: Included reference to Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175, Rev 02. 3. Part 1. B., Concurrent Requirements: Updated to show current supplier service bulletin, MXP1/4-35-175 as Revision 02.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 5 of 694. Part 1. C., Reason: Added identification of the reason for revision 1. 5. Part 1. D., Description: Added information that additional work is needed for airplanes that have accomplished the original issue of this service bulletin. 6. Part 1. E., Compliance: Added FAA Notice of Proposed Rule Making 2010-NM-094-AD. 7. Part 1. J., References: Updated the revision level of the supplier service bulletin and added FAA Notice of Proposed Rule Making 2010-NM-094-AD. 8. Part 3. Accomplishment Instructions, B., Work Instructions: – Step 2, All Groups, Part (a.), changed "Go to step 7" to "Go to step 11" and added steps for all airplane Groups. – Added Step 3, Close the shutoff valve on the crew oxygen cylinder. – Step 10, All Groups, Added " If not previously accomplished". 9. Figures 1-8, changed footnotes (b) and (c). 10. Figures 9-16, added footnote (c). 11. Figure 12, changed footnote. Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity, to show the location of important changes. Pages with no vertical lines have no important changes. **REVISION HISTORY** December 14, 2009 Original Issue: November 07, 2011 Revision 1:

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 6 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT**

### Commercial **Airplanes** 

# 737 Service Bulletin **ALERT Summary**  **Number: 737-35A1121** Original Issue: December 14, 2009 Revision 1: November 07, 2011 ATA System: 3512 **SUBJECT:** OXYGEN - Crew Oxygen System - Crew Oxygen Mask Stowage Box Unit - Inspect/Replace THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OWNER. **CONCURRENT REQUIREMENTS** Refer to Paragraph 1.B., Concurrent Requirements. **BACKGROUND** Boeing has been notified by the supplier that a limited quantity of crew oxygen mask stowage box units, part number MXP147-5, MXP147-2, MXP410-1, manufactured between 12 July 2007 and 20 November 2007, were possibly delivered with a burr in the inlet fitting. This burr may break loose during test or operation and may pose an ignition source or cause an inlet valve to jam restricting the flow of oxygen. If this service bulletin is not accomplished, a burr may break loose during test or operation and pose an ignition source or cause an inlet valve to jam, restricting the flow of oxygen. Boeing Service Related Problem (SRP) 737-SRP-35-0044 is related to this service bulletin. **ACTION** Perform a General Visual Inspection of the crew oxygen mask stowage box units. The crew oxygen mask stowage box units do not need to be fully removed to do the inspection. Loosen the four quarter turn fasteners and lift the crew oxygen mask stowage box unit enough to read the serial number. Perform a General Visual Inspection for affected serial numbers identified in the Zodiac Services (Intertechnique) service bulletin, MXP1/4-35-175 Rev 02. Crew oxygen mask stowage box units that do not have affected serial numbers require no further action. Stow the crew oxygen mask stowage box unit. Tighten the four quarter turn fasteners. Crew oxygen mask stowage box units that have affected serial numbers are to be replaced. Perform functional testing on all replaced crew oxygen mask stowage box units.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 7 of 69Crew oxygen mask stowage box units that have been inspected in accordance with the original issue of this service bulletin that did not have affected serial numbers require verification of maintenance records inspection or re-inspection of the crew oxygen mask stowage box unit in accordance with Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 R02. **EFFECTIVITY** 737-700, 737-700C, 737-800, 737-900ER Airplanes. Refer to Paragraph 1.A.1., Airplanes for the list of affected airplanes. **COMPLIANCE** Federal Aviation Administration (FAA) Notice of Proposed Rule Making 2010-NM-094-AD, is related to this service bulletin. Boeing recommends that the inspection and any applicable replacement given in this service bulletin be done within 24 months after the original issue date of this service bulletin. **INDUSTRY SUPPORT INFORMATION** Boeing warranty remedies are not available for the operator action(s) given in this service bulletin. Please refer to Zodiac Services (Intertechnique), Service Bulletin MXP1/4-35-175, Rev 02 for more information. **MANPOWER** Refer to Paragraph 1.G., Manpower. **MATERIAL INFORMATION** Operator Supplied Parts/Materials. Refer to Paragraph 2.A., Material - Price and Availability

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 8 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 9 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT**BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 10 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT**

BLANK PAGE

### Commercial **Airplanes** 

# 737 Service Bulletin **ALERT Number: 737-35A1121**  Original Issue: December 14, 2009 Revision 1: November 07, 2011 ATA System: 3512 **SUBJECT:** OXYGEN - Crew Oxygen System - Crew Oxygen Mask Stowage Box Unit - Inspect/Replace THIS BULLETIN IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS SERVICE BULLETIN TO THE NEW OWNER. **1. PLANNING INFORMATION A. Effectivity**  1. Airplanes This service bulletin is for the airplanes shown below. Refer to Service Bulletin Index Document D6-19567 Part 3 for Airplane Variable Number, Line Number, and Serial Number data.
**DESCRIPTION CONFIGURATION**  **GROUP** 737-700/-700C/-800/900ER Airplanes - Part number MXP147-5 (Captain, First Officer, First Observer) - 1
737-700/-800/-900ER Airplanes - Part number MXP147-2 (Captain, First Officer) - 2
737-700/-800/-900ER Airplanes - Part number MXP410-1 (Captain, First Officer) - 3
737-700/-800 Airplanes - Part number MXP147-5 and MXP410-1 (Captain, First Officer, First Observer) - 4
737-700 Airplanes - Part number MXP147-5 (Captain, First Officer)

- 5 737-800 Airplanes - Part number MXP147-2 (Captain, First Officer, First Observer) - 6

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 11 of 69**DESCRIPTION CONFIGURATION**  **GROUP** 737-700/-800 Airplanes - Part number MXP410-1 (Captain, First Officer, First Observer, Second Observer) - 7
737-700/-700C/-800 Airplanes - Part number MXP410-1 (Captain, First Officer, First Observer) - 8

Airplane Models: 737-700, 737-700C, 737-800, 737-900ER **Group Variable Number**  4 YB969 - YB973 2 YC750 1 YF106 - YF107 7 YF111 1 YF176 1 YG114 5 YG118 - YG119 1 YG701 8 YG711 2 YH005 - YH007 2 YH009 - YH010 1 YH051 - YH052 3 YH101 - YH106 3 YJ559 - YJ561 3 YJ595 - YJ596 2 YJ873 8 YJ929 8 YJ952 1 YJ953 1 YK308 - YK309 4 YK495 2 YK515 - YK516 2 YK634 1 YK644

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 12 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT Group**  **Variable Number** 1 YK658 - YK660 1 YK709 1 YK718 - YK719 4 YK918 1 YK922 - YK924 1 YK949 - YK951 3 YK969 - YK971 8 YK983 - YK984 1 YL016 3 YL024 2 YL068 - YL069 3 YL076 - YL077 2 YL103 - YL111 4 YL203 - YL206 2 YL281 2 YL316 2 YL371 - YL373 4 YL424 - YL426 1 YL435 - YL437 4 YL504 6 YL531 7 YL561 2 YL602 - YL604 3 YL605 - YL606 1 YL901 - YL903 3 YL931 - YL932 8 YM513 - YM515 4 YM645 - YM646 8 YN012 - YN014 7 YN015 2 YN022 - YN023 1 YN078 - YN079 2 YN091 - YN092

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 13 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT Group**  **Variable Number** 2 YN121 2 YN212 - YN214 3 YN231 2. Spares Affected Examine your spares supply for the parts or components identified in Paragraph 2.C., Parts Necessary for Each Airplane. If any parts or components are found, refer to Paragraph 2.C. for the recommended use. **B. Concurrent Requirements** The service bulletin listed below must be done before or at the same time as this service bulletin: **Description Service Bulletin**  **Company** Provides inspection information and list of affected serial numbers. MXP1/4-35-175, Rev. 02 Zodiac Services (Intertechnique)

**C. Reason** Boeing has been notified by the supplier that a limited quantity of crew oxygen mask stowage box units, part number MXP147-5, MXP147-2, MXP410-1, manufactured between 12 July 2007 and 20 November 2007, were possibly delivered with a burr in the inlet fitting. This burr may break loose during test or operation and may pose an ignition source or cause an inlet valve to jam restricting the flow of oxygen. If this service bulletin is not accomplished, a burr may break loose during test or operation and pose an ignition source or cause an inlet valve to jam, restricting the flow of oxygen. Boeing Service Related Problem (SRP) 737-SRP-35-0044 is related to this service bulletin. Revision 1 is sent to add a crew oxygen mask stowage box unit inspection in accordance with revision 02 of Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175. **D. Description** Perform a General Visual Inspection of the crew oxygen mask stowage box units. The crew oxygen mask stowage box units do not need to be fully removed to do the inspection. Loosen the four quarter turn fasteners and lift the crew oxygen mask stowage box unit enough to read the serial number. Perform a General Visual Inspection for affected serial numbers identified in the Zodiac Services (Intertechnique) service bulletin, MXP1/4-35-175 Rev 02. Crew oxygen mask stowage box units that do not have affected serial numbers require no further action. Stow the crew oxygen mask stowage box unit. Tighten the four quarter turn fasteners. Crew oxygen mask stowage box units that have affected serial numbers are to be replaced. Perform functional testing on all replaced crew oxygen mask stowage box units.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 14 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT**More work is necessary on airplanes changed in accordance with the original issue of this service bulletin to inspect the crew oxygen mask stowage box unit in accordance with revision 02 of Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175. The work in this service bulletin is done in the maintenance zone(s) given below. **Group 1:**
**Affected Maintenance Zones Zone**  **Model** 211, 212 737-700, 737-700C, 737-800, 737-900ER **Group 2-3:**
**Affected Maintenance Zones Zone**  **Model** 211, 212 737-700, 737-800, 737-900ER **Group 4, 7:**
**Affected Maintenance Zones Zone**  **Model** 211, 212 737-700, 737-800 **Group 5:**
**Affected Maintenance Zones Zone**  **Model** 211, 212 737-700 **Group 6:**
**Affected Maintenance Zones Zone**  **Model** 211, 212 737-800 **Group 8:**
**Affected Maintenance Zones Zone**  **Model** 211, 212 737-700, 737-700C, 737-800

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 15 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT E. Compliance**  Federal Aviation Administration (FAA) Notice of Proposed Rule Making 2010-NM-094-AD, is related to this service bulletin. Boeing recommends that the inspection and any applicable replacement given in this service bulletin be done within 24 months after the original issue date of this service bulletin. **F. Approval** This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified in this service bulletin comply with the applicable regulations and are FAA approved, as well as European Aviation Safety Agency (EASA)/Joint Aviation Authorities (JAA) approved for all EASA/JAA approved airplanes listed in the service bulletin effectivity. This service bulletin and its approval were based on the airplane in its original Boeing delivery configuration or as modified by other approved Boeing changes. If an airplane has a non-Boeing modification or repair that affects a component or system also affected by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency approval before incorporating this service bulletin. **G. Manpower** The table below shows an estimate of the task hours necessary to do this inspection for each crew oxygen mask stowage box unit. This estimate is for direct labor only, done by an experienced crew. Adjust the estimate with operator task hour data if necessary. The estimate does not include lost time. These are some examples of lost time: • Time to adjust to the workplace • Time to schedule the work • Time to inspect the work • Time to find the tools. **Group 1: Elapsed Hours**  **Task Hours Number of Persons**  **Task** 0.25 0.25 1 Open Access 0.15 0.15 1 Figure 1 0.75 0.75 1 Figure 9 1.05 1.05 1 Test 0.25 0.25 1 Close Access 0.65 (b) 0.65 (b) INSPECTION ONLY TOTAL FOR EACH AIRPLANE 2.45 (a), (b) 2.45 (a), (b) INSPECTION AND REPLACEMENT TOTAL FOR EACH AIRPLANE

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 16 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT Group 2:**  **Elapsed Hours Task Hours**  **Number of Persons Task**  0.25 0.25 1 Open Access 0.10 0.10 1 Figure 2 0.50 0.50 1 Figure 10 0.95 0.95 1 Test 0.25 0.25 1 Close Access 0.60 (b) 0.60 (b) INSPECTION ONLY TOTAL FOR EACH AIRPLANE 2.05 (a), (b) 2.05 (a), (b) INSPECTION AND REPLACEMENT TOTAL FOR EACH AIRPLANE **Group 3: Elapsed Hours**  **Task Hours Number of Persons**  **Task** 0.25 0.25 1 Open Access 0.10 0.10 1 Figure 3 0.50 0.50 1 Figure 11 0.95 0.95 1 Test 0.25 0.25 1 Close Access 0.60 (b) 0.60 (b) INSPECTION ONLY TOTAL FOR EACH AIRPLANE 2.05 (a), (b) 2.05 (a), (b) INSPECTION AND REPLACEMENT TOTAL FOR EACH AIRPLANE **Group 4: Elapsed Hours**  **Task Hours Number of Persons**  **Task** 0.25 0.25 1 Open Access 0.15 0.15 1 Figure 4 0.75 0.75 1 Figure 12 1.05 1.05 1 Test 0.25 0.25 1 Close Access 0.65 (b) 0.65 (b) INSPECTION ONLY TOTAL FOR EACH AIRPLANE 2.45 (a), (b) 2.45 (a), (b) INSPECTION AND REPLACEMENT TOTAL FOR EACH AIRPLANE

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 17 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT Group 5:**  **Elapsed Hours Task Hours**  **Number of Persons Task**  0.25 0.25 1 Open Access 0.10 0.10 1 Figure 5 0.50 0.50 1 Figure 13 0.95 0.95 1 Test 0.25 0.25 1 Close Access 0.60 (b) 0.60 (b) INSPECTION ONLY TOTAL FOR EACH AIRPLANE 2.05 (a), (b) 2.05 (a), (b) INSPECTION AND REPLACEMENT TOTAL FOR EACH AIRPLANE **Group 6: Elapsed Hours**  **Task Hours Number of Persons**  **Task** 0.25 0.25 1 Open Access 0.15 0.15 1 Figure 6 0.75 0.75 1 Figure 14 1.05 1.05 1 Test 0.25 0.25 1 Close Access 0.65 (b) 0.65 (b) INSPECTION ONLY TOTAL FOR EACH AIRPLANE 2.45 (a), (b) 2.45 (a), (b) INSPECTION AND REPLACEMENT TOTAL FOR EACH AIRPLANE **Group 7: Elapsed Hours**  **Task Hours Number of Persons**  **Task** 0.25 0.25 1 Open Access 0.20 0.20 1 Figure 7 1.00 1.00 1 Figure 15 1.15 1.15 1 Test 0.25 0.25 1 Close Access 0.70 (b) 0.70 (b) INSPECTION ONLY TOTAL FOR EACH AIRPLANE 2.85 (a), (b) 2.85 (a), (b) INSPECTION AND REPLACEMENT TOTAL FOR EACH AIRPLANE

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 18 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT Group 8:**  **Elapsed Hours Task Hours**  **Number of Persons Task**  0.25 0.25 1 Open Access 0.15 0.15 1 Figure 8 0.75 0.75 1 Figure 16 1.05 1.05 1 Test 0.25 0.25 1 Close Access 0.65 (b) 0.65 (b) INSPECTION ONLY TOTAL FOR EACH AIRPLANE 2.45 (a), (b) 2.45 (a), (b) INSPECTION AND REPLACEMENT TOTAL FOR EACH AIRPLANE (a) The time to package and return the affected crew oxygen mask stowage box unit in accordance with Intertechnique (Avox-Eros Services INC.) Service Bulletin MXP1/4-35-175 is not included. (b) The time to perform the General Visual Inspection in accordance with Intertechnique (Avox-Eros Services INC.) Service Bulletin MXP1/4-35-175 is not included. **H. Weight and Balance Changes** None. **I. Electrical Load Data** Not changed. **J. References** 1. Existing Data a. Service Related Problem (SRP) 737-SRP-35-0044 b. 737-600/700/800/900 Aircraft Maintenance Manual (AMM) 23-51-00, 35-00-00, 35-12-00, 35-12-85, 52-51-00 c. Standard Overhaul Practices Manual (SOPM) 20-70-01 d. Zodiac Services (Intertechnique), Service Bulletin MXP1/4-35-175, Rev. 02 **NOTE:** The supplier was told to send copies of the service bulletin to each operator. e. FAA Notice of Proposed Rule Making 2010-NM-094-AD. 2. Data supplied with this Service Bulletin None.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 19 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT**3. Installation Drawings Used in the Preparation of this Service Bulletin

**Title Drawing Number**  EQUIPMENT INSTALLATION - CREW OXYGEN 232A8100 These drawings were used to prepare this service bulletin. These drawings are not necessary to make the specified changes, and are not supplied with this service bulletin. These drawings may not be applicable to all airplane configurations or operators. **K. Publications Affected** 1. Publications: None. 2. Damage Tolerance Based Structural Inspections: Boeing has evaluated this service bulletin for effects on Fatigue Critical Structure (FCS) and for changes to Damage Tolerance Inspections (DTI) required in the Maintenance Program. This service bulletin does not affect FCS, therefore DTIs are not necessary. **L. Interchangeability and Intermixability of Parts** Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 20 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT 2. MATERIAL INFORMATION**  **A. Material - Price and Availability** The operator can supply the parts and materials shown in Paragraph 2.C., Parts Necessary for Each Airplane. Refer to Zodiac Services (Intertechnique) service bulletin, MXP1/4-35-175 Rev 02. **B. Industry Support Information** Boeing warranty remedies are not available for the operator action(s) given in this service bulletin. Please refer to Zodiac Services (Intertechnique), Service Bulletin MXP1/4-35-175, Rev 02 for more information. **C. Parts Necessary For Each Airplane** 1. Kits/Parts None. 2. Parts and Materials Supplied by the Operator **Group 1:**
**Notes Name**  **QTY Part Number /**  **Specification** (a), (c), (e) Crew oxygen mask stowage box unit 3 Part number MXP147-5 (b), (d) Cap - Protective, Aluminum, Flare- less Tube 1-3 BACC14AG5 (b), (d) Plug - Protective, Aluminum, Flare- less Tube 1-3 BACP20BG5(a) Package and return affected serial number crew oxygen mask stowage box units in accordance with Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175 Rev 02.(b) The quantity can vary depending on the work sequence. The maximum is listed for concurrent accomplishment of all crew oxygen mask stowage box units. One is required if work is done in serial. (c) Intertechnique, 61 Rue Pierre Curie, Boite Postale 1, 78734 Plaisir Cedex, France, Cage Code F5341, Phone: 01 30 54 82 00. (Avox-Eros Services, INC., 6734 Valjean Avenue, Van Nuys, CA., 91406-5818, Cage Code 55912, Phone: 818-435-0945, Fax: 818-435- 0995.) (d) Caplugs LLC., DBA Mokon Div Caplugs, 2150 Elmwood Ave., Buffalo, NY., 14207-7198, Cage Code 99017, Phone: 716-876-9855, Fax: 716-874-1680.(e) Crew oxygen mask stowage box units can be ordered from Zodiac Services (Intertechnique) per service bulletin, MXP1/4-35-175 Rev 02.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 21 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT Group 2:** 
**Notes Name**  **QTY Part Number /**  **Specification** (a), (c), (e) Crew oxygen mask stowage box unit 2 Part number MXP147-2 (b), (d) Cap - Protective, Aluminum, Flare- less Tube 1-2 BACC14AG5 (b), (d) Plug - Protective, Aluminum, Flare- less Tube 1-2 BACP20BG5(a) Package and return affected serial number crew oxygen mask stowage box units in accordance with Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175 Rev 02.(b) The quantity can vary depending on the work sequence. The maximum is listed for concurrent accomplishment of all crew oxygen mask stowage box units. One is required if work is done in serial. (c) Intertechnique, 61 Rue Pierre Curie, Boite Postale 1, 78734 Plaisir Cedex, France, Cage Code F5341, Phone: 01 30 54 82 00. (Avox-Eros Services, INC., 6734 Valjean Avenue, Van Nuys, CA., 91406-5818, Cage Code 55912, Phone: 818-435-0945, Fax: 818-435- 0995.) (d) Caplugs LLC., DBA Mokon Div Caplugs, 2150 Elmwood Ave., Buffalo, NY., 14207-7198, Cage Code 99017, Phone: 716-876-9855, Fax: 716-874-1680.(e) Crew oxygen mask stowage box units can be ordered from Zodiac Services (Intertechnique) per service bulletin, MXP1/4-35-175 R02. **Group 3:**
**Notes Name**  **QTY Part Number /**  **Specification** (a), (c), (e) Crew oxygen mask stowage box unit 2 Part number MXP410-1 (b), (d) Cap - Protective, Aluminum, Flare- less Tube 1-2 BACC14AG5 (b), (d) Plug - Protective, Aluminum, Flare- less Tube 1-2 BACP20BG5(a) Package and return affected serial number crew oxygen mask stowage box units in accordance with Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175 Rev 02.(b) The quantity can vary depending on the work sequence. The maximum is listed for concurrent accomplishment of all crew oxygen mask stowage box units. One is required if work is done in serial. (c) Intertechnique, 61 Rue Pierre Curie, Boite Postale 1, 78734 Plaisir Cedex, France, Cage Code F5341, Phone: 01 30 54 82 00. (Avox-Eros Services, INC., 6734 Valjean Avenue, Van Nuys, CA., 91406-5818, Cage Code 55912, Phone: 818-435-0945, Fax: 818-435- 0995.)

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 22 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT Group 3:** 
**Notes Name**  **QTY Part Number /**  **Specification** (d) Caplugs LLC., DBA Mokon Div Caplugs, 2150 Elmwood Ave., Buffalo, NY., 14207-7198, Cage Code 99017, Phone: 716-876-9855, Fax: 716-874-1680.(e) Crew oxygen mask stowage box units can be ordered from Zodiac Services (Intertechnique) per service bulletin, MXP1/4-35-175 R02. **Group 4:**
**Notes Name**  **QTY Part Number /**  **Specification** (a), (c), (e) Crew oxygen mask stowage box unit 2 Part number MXP410-1 (a), (c) Crew oxygen mask stowage box unit 1 Part number MXP147-5 (b), (d) Cap - Protective, Aluminum, Flare- less Tube 1-3 BACC14AG5 (b), (d) Plug - Protective, Aluminum, Flare- less Tube 1-3 BACP20BG5(a) Package and return affected serial number crew oxygen mask stowage box units in accordance with Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175 Rev 02.(b) The quantity can vary depending on the work sequence. The maximum is listed for concurrent accomplishment of all crew oxygen mask stowage box units. One is required if work is done in serial. (c) Intertechnique, 61 Rue Pierre Curie, Boite Postale 1, 78734 Plaisir Cedex, France, Cage Code F5341, Phone: 01 30 54 82 00. (Avox-Eros Services, INC., 6734 Valjean Avenue, Van Nuys, CA., 91406-5818, Cage Code 55912, Phone: 818-435-0945, Fax: 818-435- 0995.) (d) Caplugs LLC., DBA Mokon Div Caplugs, 2150 Elmwood Ave., Buffalo, NY., 14207-7198, Cage Code 99017, Phone: 716-876-9855, Fax: 716-874-1680.(e) Crew oxygen mask stowage box units can be ordered from Zodiac Services (Intertechnique) per service bulletin, MXP1/4-35-175 Rev 02. **Group 5:**
**Notes Name**  **QTY Part Number /**  **Specification** (a), (c), (e) Crew oxygen mask stowage box unit 2 Part number MXP147-5 (b), (d) Cap - Protective, Aluminum, Flare- less Tube 1-2 BACC14AG5

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 23 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT Group 5:** 
**Notes Name**  **QTY Part Number /**  **Specification** (b), (d) Plug - Protective, Aluminum, Flare- less Tube 1-2 BACP20BG5(a) Package and return affected serial number crew oxygen mask stowage box units in accordance with Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175 Rev 02.(b) The quantity can vary depending on the work sequence. The maximum is listed for concurrent accomplishment of all crew oxygen mask stowage box units. One is required if work is done in serial. (c) Intertechnique, 61 Rue Pierre Curie, Boite Postale 1, 78734 Plaisir Cedex, France, Cage Code F5341, Phone: 01 30 54 82 00. (Avox-Eros Services, INC., 6734 Valjean Avenue, Van Nuys, CA., 91406-5818, Cage Code 55912, Phone: 818-435-0945, Fax: 818-435- 0995.) (d) Caplugs LLC., DBA Mokon Div Caplugs, 2150 Elmwood Ave., Buffalo, NY., 14207-7198, Cage Code 99017, Phone: 716-876-9855, Fax: 716-874-1680.(e) Crew oxygen mask stowage box units can be ordered from Zodiac Services (Intertechnique) per service bulletin, MXP1/4-35-175 Rev 02. **Group 6:**
**Notes Name**  **QTY Part Number /**  **Specification** (a), (c), (e) Crew oxygen mask stowage box unit 3 Part number MXP147-2 (b), (d) Cap - Protective, Aluminum, Flare- less Tube 1-3 BACC14AG5 (b), (d) Plug - Protective, Aluminum, Flare- less Tube 1-3 BACP20BG5(a) Package and return affected serial number crew oxygen mask stowage box units in accordance with Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175 Rev 02.(b) The quantity can vary depending on the work sequence. The maximum is listed for concurrent accomplishment of all crew oxygen mask stowage box units. One is required if work is done in serial. (c) Intertechnique, 61 Rue Pierre Curie, Boite Postale 1, 78734 Plaisir Cedex, France, Cage Code F5341, Phone: 01 30 54 82 00. (Avox-Eros Services, INC., 6734 Valjean Avenue, Van Nuys, CA., 91406-5818, Cage Code 55912, Phone: 818-435-0945, Fax: 818-435- 0995.) (d) Caplugs LLC., DBA Mokon Div Caplugs, 2150 Elmwood Ave., Buffalo, NY., 14207-7198, Cage Code 99017, Phone: 716-876-9855, Fax: 716-874-1680.(e) Crew oxygen mask stowage box units can be ordered from Zodiac Services (Intertechnique) per service bulletin, MXP1/4-35-175 Rev 02.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 24 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT Group 7:** 
**Notes Name**  **QTY Part Number /**  **Specification** (a), (c), (e) Crew oxygen mask stowage box unit 4 Part number MXP410-1 (b), (d) Cap - Protective, Aluminum, Flare- less Tube 1-4 BACC14AG5 (b), (d) Plug - Protective, Aluminum, Flare- less Tube 1-4 BACP20BG5(a) Package and return affected serial number crew oxygen mask stowage box units in accordance with Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175 Rev 02.(b) The quantity can vary depending on the work sequence. The maximum is listed for concurrent accomplishment of all crew oxygen mask stowage box units. One is required if work is done in serial. (c) Intertechnique, 61 Rue Pierre Curie, Boite Postale 1, 78734 Plaisir Cedex, France, Cage Code F5341, Phone: 01 30 54 82 00. (Avox-Eros Services, INC., 6734 Valjean Avenue, Van Nuys, CA., 91406-5818, Cage Code 55912, Phone: 818-435-0945, Fax: 818-435- 0995.) (d) Caplugs LLC., DBA Mokon Div Caplugs, 2150 Elmwood Ave., Buffalo, NY., 14207-7198, Cage Code 99017, Phone: 716-876-9855, Fax: 716-874-1680.(e) Crew oxygen mask stowage box units can be ordered from Zodiac Services (Intertechnique) per service bulletin, MXP1/4-35-175 Rev 02. **Group 8:**
**Notes Name**  **QTY Part Number /**  **Specification** (a), (c), (e) Crew oxygen mask stowage box unit 3 Part number MXP410-1 (b), (d) Cap - Protective, Aluminum, Flare- less Tube 1-3 BACC14AG5 (b), (d) Plug - Protective, Aluminum, Flare- less Tube 1-3 BACP20BG5(a) Package and return affected serial number crew oxygen mask stowage box units in accordance with Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175 Rev 02.(b) The quantity can vary depending on the work sequence. The maximum is listed for concurrent accomplishment of all crew oxygen mask stowage box units. One is required if work is done in serial. (c) Intertechnique, 61 Rue Pierre Curie, Boite Postale 1, 78734 Plaisir Cedex, France, Cage Code F5341, Phone: 01 30 54 82 00. (Avox-Eros Services, INC., 6734 Valjean Avenue, Van Nuys, CA., 91406-5818, Cage Code 55912, Phone: 818-435-0945, Fax: 818-435- 0995.)

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 25 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT Group 8:** 
**Notes Name**  **QTY Part Number /**  **Specification** (d) Caplugs LLC., DBA Mokon Div Caplugs, 2150 Elmwood Ave., Buffalo, NY., 14207-7198, Cage Code 99017, Phone: 716-876-9855, Fax: 716-874-1680.(e) Crew oxygen mask stowage box units can be ordered from Zodiac Services (Intertechnique) per service bulletin, MXP1/4-35-175 Rev 02.
3. Parts Modified and Reidentified See Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175, Rev 02. 4. Parts Removed and Not Replaced None. **D. Parts Necessary to Change Spares** Boeing has canvassed Boeing Spares and Operator Spares inventory and determined there to be none. **E. Special Tooling - Price and Availability** None. **F. Special Tooling Necessary to do this Service Bulletin** No special tools or equipment are necessary to do the change in this service bulletin. But, maintenance and overhaul tools in the manuals given in Paragraph 1.J., References, can be necessary. Examine operator tool supply to make sure all necessary tools are available.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 26 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT 3. ACCOMPLISHMENT INSTRUCTIONS**  **A. GENERAL INFORMATION CAUTION:**  KEEP THE WORK AREA, WIRES AND ELECTRICAL BUNDLES CLEAN OF METAL PARTICLES OR CONTAMINATION WHEN YOU USE TOOLS. UNWANTED MATERIAL, METAL PARTICLES OR CONTAMINATION CAUGHT IN WIRE BUNDLES CAN CAUSE DAMAGE TO THE BUNDLES. DAMAGED WIRE BUNDLES CAN CAUSE SPARKS OR OTHER ELECTRICAL DAMAGE. **NOTE:** 1. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for definition of the acronyms. 2. Obey all of the warnings and cautions given in the specified manual sections. 3. A General Visual Inspection is defined as: A visual examination of an interior or exterior area, installation or assembly to detect obvious damage, failure or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to enhance visual access to all exposed surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight or drop-light and may require removal or opening of access panels or doors. Stands, ladders or platforms may be required to gain proximity to the area being checked. 4. These work instructions refer to procedures included in other Boeing documents. When the words "refer to" are used and the operator has an accepted alternative procedure, the accepted alternative procedure can be used. When the words "in accordance with" are included in the instruction, the procedure in the Boeing document must be used.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 27 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT B. WORK INSTRUCTIONS**  **WARNING:** MAKE SURE THAT THE OXYGEN SYSTEM IS DEACTIVATED AND THE OXYGEN CYLINDERS ARE FULLY CLOSED. IF THE OXYGEN SYSTEM IS NOT DEACTIVATED AND THE OXYGEN CYLINDERS ARE NOT FULLY CLOSED, THE OXYGEN SYSTEM MAY BE PRESSURIZED. IF WORK IS DONE ON A PRESSURIZED OXYGEN SYSTEM, INJURY TO PERSONNEL OR DAMAGE TO EQUIPMENT CAN OCCUR. **WARNING:** CLOSE THE SHUTOFF VALVE ON THE CREW OXYGEN CYLINDERS SLOWLY. FIRE CAN RESULT IF VALVE IS CLOSED TOO QUICKLY. THIS CAN CAUSE INJURY TO PERSONS AND DAMAGE TO THE AIRPLANE AND EQUIPMENT. **CAUTION:** DO NOT TIGHTEN THE SHUTOFF VALVE ON THE CREW OXYGEN CYLINDERS MORE THAN 25 POUND-INCHES. THIS CAN CAUSE DAMAGE TO THE SHUTOFF VALVE. **CAUTION:** MAXIMUM PERMITTED OPEN TIME FOR OXYGEN TUBES, HOSES AND COMPONENTS IS 5 MINUTES. **CAUTION:** OXYGEN SYSTEM COMPONENTS REQUIRE SPECIAL CARE AND HANDLING PROCEDURES. REVIEW THE SAFETY AND MAINTENANCE PROCESSES SHOWN IN 737 AMM 35-00-00 PRIOR TO MAKING ANY CHANGES TO THE OXYGEN SYSTEM. 1. Open access to flight compartment, refer to 737-600/700/800/900 AMM 52-51-00 as an accepted procedure.
2. **Group 1:** Perform a General Visual Inspection of the crew oxygen mask stowage box units in accordance with Figure 1. – (a.) No more work is required for crew oxygen mask stowage box units that do not have affected serial numbers. Return the crew oxygen mask stowage box unit to its installed position and tighten the four quarter turn fasteners on the crew oxygen mask stowage box unit. Go to step 11. – (b.) Crew oxygen mask stowage box units that have affected serial numbers require replacement. Go to step 3. – (c.) Crew oxygen mask stowage box units that have affected serial numbers which were changed in accordance with the original issue of this service bulletin require additional work. Accomplish Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 R02. **Group 2:** Perform a General Visual Inspection of the crew oxygen mask stowage box units in accordance with Figure 2. – (a.) No more work is required for crew oxygen mask stowage box units that do not have affected serial numbers. Return the crew oxygen mask stowage box unit to its installed position and tighten the four quarter turn fasteners on the crew oxygen mask stowage box unit. Go to step 11. – (b.) Crew oxygen mask stowage box units that have affected serial numbers require replacement. Go to step 3. – (c.) Crew oxygen mask stowage box units that have affected serial numbers which were changed in accordance with the original issue of this service bulletin require additional work. Accomplish Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 R02.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 28 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT Group 3:**  Perform a General Visual Inspection of the crew oxygen mask stowage box units in accordance with Figure 3. – (a.) No more work is required for crew oxygen mask stowage box units that do not have affected serial numbers. Return the crew oxygen mask stowage box unit to its installed position and tighten the four quarter turn fasteners on the crew oxygen mask stowage box unit. Go to step 11. – (b.) Crew oxygen mask stowage box units that have affected serial numbers require replacement. Go to step 3. – (c.) Crew oxygen mask stowage box units that have affected serial numbers which were changed in accordance with the original issue of this service bulletin require additional work. Accomplish Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 R02. **Group 4:** Perform a General Visual Inspection of the crew oxygen mask stowage box units in accordance with Figure 4. – (a.) No more work is required for crew oxygen mask stowage box units that do not have affected serial numbers. Return the crew oxygen mask stowage box unit to its installed position and tighten the four quarter turn fasteners on the crew oxygen mask stowage box unit. Go to step 11. – (b.) Crew oxygen mask stowage box units that have affected serial numbers require replacement. Go to step 3. – (c.) Crew oxygen mask stowage box units that have affected serial numbers which were changed in accordance with the original issue of this service bulletin require additional work. Accomplish Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 R02. **Group 5:** Perform a General Visual Inspection of the crew oxygen mask stowage box units in accordance with Figure 5. – (a.) No more work is required for crew oxygen mask stowage box units that do not have affected serial numbers. Return the crew oxygen mask stowage box unit to its installed position and tighten the four quarter turn fasteners on the crew oxygen mask stowage box unit. Go to step 11. – (b.) Crew oxygen mask stowage box units that have affected serial numbers require replacement. Go to step 3. – (c.) Crew oxygen mask stowage box units that have affected serial numbers which were changed in accordance with the original issue of this service bulletin require additional work. Accomplish Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 R02. **Group 6:** Perform a General Visual Inspection of the crew oxygen mask stowage box units in accordance with Figure 6.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 29 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT**– (a.) No more work is required for crew oxygen mask stowage box units that do not have affected serial numbers. Return the crew oxygen mask stowage box unit to its installed position and tighten the four quarter turn fasteners on the crew oxygen mask stowage box unit. Go to step 11. – (b.) Crew oxygen mask stowage box units that have affected serial numbers require replacement. Go to step 3. – (c.) Crew oxygen mask stowage box units that have affected serial numbers which were changed in accordance with the original issue of this service bulletin require additional work. Accomplish Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 R02. **Group 7:** Perform a General Visual Inspection of the crew oxygen mask stowage box units in accordance with Figure 7. – (a.) No more work is required for crew oxygen mask stowage box units that do not have affected serial numbers. Return the crew oxygen mask stowage box unit to its installed position and tighten the four quarter turn fasteners on the crew oxygen mask stowage box unit. Go to step 11. – (b.) Crew oxygen mask stowage box units that have affected serial numbers require replacement. Go to step 3. – (c.) Crew oxygen mask stowage box units that have affected serial numbers which were changed in accordance with the original issue of this service bulletin require additional work. Accomplish Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 R02. **Group 8:** Perform a General Visual Inspection of the crew oxygen mask stowage box units in accordance with Figure 8. – (a.) No more work is required for crew oxygen mask stowage box units that do not have affected serial numbers. Return the crew oxygen mask stowage box unit to its installed position and tighten the four quarter turn fasteners on the crew oxygen mask stowage box unit. Go to step 11. – (b.) Crew oxygen mask stowage box units that have affected serial numbers require replacement. Go to step 3. – (c.) Crew oxygen mask stowage box units that have affected serial numbers which were changed in accordance with the original issue of this service bulletin require additional work. Accomplish Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 R02. 3. Open access to the crew oxygen cylinders. Close the shutoff valve. 4. Detach crew oxygen mask from the affected crew oxygen mask stowage box unit, retain for re-installation. Refer to 737-600/700/800/900 AMM 35-12-85 as an accepted procedure.
5. **Group 1:** Replace affected crew oxygen mask stowage box units in accordance with Figure 9. **NOTE:** The oxygen supply line hose and wire bundle length will allow pulling the crew oxygen mask stowage box unit up onto the console before the disconnections are made. **Group 2:** Replace affected crew oxygen mask stowage box units in accordance with Figure 10.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 30 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT NOTE:**  The oxygen supply line hose and wire bundle length will allow pulling the crew oxygen mask stowage box unit up onto the console before the disconnections are made. **Group 3:** Replace affected crew oxygen mask stowage box units in accordance with Figure 11. **NOTE:** The oxygen supply line hose and wire bundle length will allow pulling the crew oxygen mask stowage box unit up onto the console before the disconnections are made. **Group 4:** Replace affected crew oxygen mask stowage box units in accordance with Figure 12. **NOTE:** The oxygen supply line hose and wire bundle length will allow pulling the crew oxygen mask stowage box unit up onto the console before the disconnections are made. **Group 5:** Replace affected crew oxygen mask stowage box units in accordance with Figure 13. **NOTE:** The oxygen supply line hose and wire bundle length will allow pulling the crew oxygen mask stowage box unit up onto the console before the disconnections are made. **Group 6:** Replace affected crew oxygen mask stowage box units in accordance with Figure 14. **NOTE:** The oxygen supply line hose and wire bundle length will allow pulling the crew oxygen mask stowage box unit up onto the console before the disconnections are made. **Group 7:** Replace affected crew oxygen mask stowage box units in accordance with Figure 15. **NOTE:** The oxygen supply line hose and wire bundle length will allow pulling the crew oxygen mask stowage box unit up onto the console before the disconnections are made. **Group 8:** Replace affected crew oxygen mask stowage box units in accordance with Figure 16. **NOTE:** The oxygen supply line hose and wire bundle length will allow pulling the crew oxygen mask stowage box unit up onto the console before the disconnections are made. **WARNING:** OPEN THE SHUTOFF VALVE ON THE CREW OXYGEN CYLINDERS SLOWLY. FIRE CAN RESULT IF VALVE IS OPENED TOO QUICKLY. THIS CAN CAUSE INJURY TO PERSONS AND DAMAGE TO THE AIRPLANE AND EQUIPMENT. **CAUTION:** DO NOT TIGHTEN THE SHUTOFF VALVE ON THE CREW OXYGEN CYLINDERS MORE THAN 25 POUND-INCHES. THIS CAN CAUSE DAMAGE TO THE SHUTOFF VALVE. 6. Re-attach the crew oxygen mask to the crew oxygen mask stowage box unit and tighten the four quarter turn fasteners on the crew oxygen mask stowage box unit. Refer to 737-600/700/800/900 AMM 35-12-85 as an accepted procedure. 7. Slowly turn the crew oxygen cylinder shutoff valve until fully opened.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 31 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT**8. Close crew oxygen cylinder shutoff valve one-fourth of a turn. Install Lock wire on the shutoff valves. 9. Close access to the crew oxygen cylinders. 10. Perform oxygen system testing: – If not previously accomplished, do a leak test the crew oxygen system refer to 737-600/700/800/900 AMM 35-12-00 as an accepted procedure. – If not previously accomplished, do a crew oxygen pressure indication operational test refer to 737-600/700/800/900 AMM 35-12-00 as an accepted procedure. – If not previously accomplished, do a crew oxygen mask-regulator test refer to 737-600/700/800/900 AMM 35-12-00 as an accepted procedure. – If not previously accomplished, do an operational test the flight interphone system refer to 737-600/700/800/900 AMM 23-51-00 as an accepted procedure. 11. Close access to flight compartment, refer to 737-600/700/800/900 AMM 52-51-00 as an accepted procedure. 12. Put the airplane back to a serviceable condition.

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1: November 07, 2011 32 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 1.** 

**FIGURE 1: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 1 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 33 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT MORE DATA**  **QTY IDENTIFICATION**  **NAME TASK**  **STEP** (a) 3 MXP147-5 CREW OXYGEN MASK STOWAGE BOX UNIT Loosen 1

(b), (c) 3 MXP147-5 CREW OXYGEN MASK STOWAGE BOX UNIT Inspect 2

(a) The four quarter turn fasteners on the crew oxygen mask stowage box unit. (b) General Visual Inspection for affected part number with serial numbers in accordance with Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 Rev 02. (c) The serial number tag is on the forward side of the crew oxygen stowage box unit. The number can be read when lifting the box up to expose it. It is not necessary to detach the supply line.

**FIGURE 1: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 2 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 34 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 2.** 

**FIGURE 2: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 1 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 35 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT MORE DATA**  **QTY IDENTIFICATION**  **NAME TASK**  **STEP** (a) 2 MXP147-2 CREW OXYGEN MASK STOWAGE BOX UNIT Loosen 1

(b), (c) 2 MXP147-2 CREW OXYGEN MASK STOWAGE BOX UNIT Inspect 2

(a) The four quarter turn fasteners on the crew oxygen mask stowage box unit. (b) General Visual Inspection for affected part number with serial numbers in accordance with Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 Rev 02. (c) The serial number tag is on the forward side of the crew oxygen stowage box unit. The number can be read when lifting the box up to expose it. It is not necessary to detach the supply line.

**FIGURE 2: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 2 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 36 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 3.** 

**FIGURE 3: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 1 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 37 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT MORE DATA**  **QTY IDENTIFICATION**  **NAME TASK**  **STEP** (a) 2 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Loosen 1

(b), (c) 2 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Inspect 2

(a) The four quarter turn fasteners on the crew oxygen mask stowage box unit. (b) General Visual Inspection for affected part number with serial numbers in accordance with Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 Rev 02. (c) The serial number tag is on the forward side of the crew oxygen stowage box unit. The number can be read when lifting the box up to expose it. It is not necessary to detach the supply line.

**FIGURE 3: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 2 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 38 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 4.** 

**FIGURE 4: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 1 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 39 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT MORE DATA**  **QTY IDENTIFICATION**  **NAME TASK**  **STEP** (a) 2 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Loosen 1

(b), (c) 2 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Inspect 2

(a) 1 MXP147-5 CREW OXYGEN MASK STOWAGE BOX UNIT Loosen 3

(b), (c) 1 MXP147-5 CREW OXYGEN MASK STOWAGE BOX UNIT Inspect 4

(a) The four quarter turn fasteners on the crew oxygen mask stowage box unit. (b) General Visual Inspection for affected part number with serial numbers in accordance with Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 Rev 02. (c) The serial number tag is on the forward side of the crew oxygen stowage box unit. The number can be read when lifting the box up to expose it. It is not necessary to detach the supply line.

**FIGURE 4: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 2 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 40 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 5.** 

**FIGURE 5: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 1 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 41 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT MORE DATA**  **QTY IDENTIFICATION**  **NAME TASK**  **STEP** (a) 2 MXP147-5 CREW OXYGEN MASK STOWAGE BOX UNIT Loosen 1

(b), (c) 2 MXP147-5 CREW OXYGEN MASK STOWAGE BOX UNIT Inspect 2

(a) The four quarter turn fasteners on the crew oxygen mask stowage box unit. (b) General Visual Inspection for affected part number with serial numbers in accordance with Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 Rev 02. (c) The serial number tag is on the forward side of the crew oxygen stowage box unit. The number can be read when lifting the box up to expose it. It is not necessary to detach the supply line.

**FIGURE 5: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 2 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 42 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 6.** 

**FIGURE 6: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 1 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 43 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT MORE DATA**  **QTY IDENTIFICATION**  **NAME TASK**  **STEP** (a) 3 MXP147-2 CREW OXYGEN MASK STOWAGE BOX UNIT Loosen 1

(b), (c) 3 MXP147-2 CREW OXYGEN MASK STOWAGE BOX UNIT Inspect 2

(a) The four quarter turn fasteners on the crew oxygen mask stowage box unit. (b) General Visual Inspection for affected part number with serial numbers in accordance with Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 Rev 02. (c) The serial number tag is on the forward side of the crew oxygen stowage box unit. The number can be read when lifting the box up to expose it. It is not necessary to detach the supply line.

**FIGURE 6: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 2 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 44 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 7.** 

**FIGURE 7: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 1 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 45 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT MORE DATA**  **QTY IDENTIFICATION**  **NAME TASK**  **STEP** (a) 4 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Loosen 1

(b), (c) 4 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Inspect 2

(a) The four quarter turn fasteners on the crew oxygen mask stowage box unit. (b) General Visual Inspection for affected part number with serial numbers in accordance with Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 Rev 02. (c) The serial number tag is on the forward side of the crew oxygen stowage box unit. The number can be read when lifting the box up to expose it. It is not necessary to detach the supply line.

**FIGURE 7: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 2 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 46 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 8.** 

**FIGURE 8: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 1 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 47 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT MORE DATA**  **QTY IDENTIFICATION**  **NAME TASK**  **STEP** (a) 3 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Loosen 1

(b), (c) 3 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Inspect 2

(a) The four quarter turn fasteners on the crew oxygen mask stowage box unit. (b) General Visual Inspection for affected part number with serial numbers in accordance with Zodiac Services (Intertechnique) service bulletin MXP1/4-35-175 Rev 02. (c) The serial number tag is on the forward side of the crew oxygen stowage box unit. The number can be read when lifting the box up to expose it. It is not necessary to detach the supply line.

**FIGURE 8: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - INSPECTION (SHEET 2 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 48 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 1.** 

**FIGURE 9: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 1 OF 3)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 49 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT FIGURE 9: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT**  **(SHEET 2 OF 3)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 50 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT WARNING:**  DO NOT WORK ON THE PRESSURIZED OXYGEN SYSTEM WHEN THERE IS OIL, GREASE, FLAMMABLE SOLVENTS, LINT, METAL FILINGS, OR OTHER COMBUSTIBLE MATERIALS IN THE AREA. THESE MATERIALS CAN CAUSE A FIRE OR AN EXPLOSION WHEN THEY ARE NEAR PRESSURIZED OXYGEN. REFER TO 737 MAINTENANCE MANUAL SUBJECTS 35-00-00 AND 35-12-00 AS ACCEPTED PROCEDURES. **CAUTION:** OXYGEN SYSTEM COMPONENTS REQUIRE SPECIAL HANDLING AND PROCESSING. RETURN ANY CONTAMINATED EQUIPMENT TO VENDOR. **CAUTION:** OPEN EXPOSURE OF THE OXYGEN SYSTEM IS TO BE KEPT TO A MINIMUM. TO PROTECT THE INTEGRITY OF THE OXYGEN SYSTEM, COVER AND SEAL OPEN LINES WITH SUITABLE PLASTIC BAG, CAP, OR PLUG.

**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP**  (a), (c) 3 MXP147-5 CREW OXYGEN MASK STOWAGE BOX UNIT Remove 1

(a), (b), (c) 3 MXP147-5 CREW OXYGEN MASK STOWAGE BOX UNIT Install (Changed) 2

(a) Refer to 737-600/700/800/900 AMM 35-12-85 as an accepted procedure. (b) If the oxygen flex hose that attaches at the bottom of the crew oxygen mask stowage box unit is not to be connected to the new crew oxygen mask stowage box unit within 5 minutes, refer to 737- 600/700/800/900 AMM 35-00-00 and SOPM 20-70-01 as accepted procedures. (c) Refer to Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175, Rev 02 for detailed instructions.

**FIGURE 9: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 3 OF 3)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 51 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 2.** 

**FIGURE 10: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 1 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 52 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT WARNING:**  DO NOT WORK ON THE PRESSURIZED OXYGEN SYSTEM WHEN THERE IS OIL, GREASE, FLAMMABLE SOLVENTS, LINT, METAL FILINGS, OR OTHER COMBUSTIBLE MATERIALS IN THE AREA. THESE MATERIALS CAN CAUSE A FIRE OR AN EXPLOSION WHEN THEY ARE NEAR PRESSURIZED OXYGEN. REFER TO 737 MAINTENANCE MANUAL SUBJECTS 35-00-00 AND 35-12-00 AS ACCEPTED PROCEDURES. **CAUTION:** OXYGEN SYSTEM COMPONENTS REQUIRE SPECIAL HANDLING AND PROCESSING. RETURN ANY CONTAMINATED EQUIPMENT TO VENDOR. **CAUTION:** OPEN EXPOSURE OF THE OXYGEN SYSTEM IS TO BE KEPT TO A MINIMUM. TO PROTECT THE INTEGRITY OF THE OXYGEN SYSTEM, COVER AND SEAL OPEN LINES WITH SUITABLE PLASTIC BAG, CAP, OR PLUG.

**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP**  (a), (c) 2 MXP147-2 CREW OXYGEN MASK STOWAGE BOX UNIT Remove 1

(a), (b), (c) 2 MXP147-2 CREW OXYGEN MASK STOWAGE BOX UNIT Install (Changed) 2

(a) Refer to 737-600/700/800/900 AMM 35-12-85 as an accepted procedure. (b) If the oxygen flex hose that attaches at the bottom of the crew oxygen mask stowage box unit is not to be connected to the new crew oxygen mask stowage box unit within 5 minutes, refer to 737- 600/700/800/900 AMM 35-00-00 and SOPM 20-70-01 as accepted procedures. (c) Refer to Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175, Rev 02 for detailed instructions.

**FIGURE 10: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 2 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 53 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 3.** 

**FIGURE 11: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 1 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 54 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT WARNING:**  DO NOT WORK ON THE PRESSURIZED OXYGEN SYSTEM WHEN THERE IS OIL, GREASE, FLAMMABLE SOLVENTS, LINT, METAL FILINGS, OR OTHER COMBUSTIBLE MATERIALS IN THE AREA. THESE MATERIALS CAN CAUSE A FIRE OR AN EXPLOSION WHEN THEY ARE NEAR PRESSURIZED OXYGEN. REFER TO 737 MAINTENANCE MANUAL SUBJECTS 35-00-00 AND 35-12-00 AS ACCEPTED PROCEDURES. **CAUTION:** OXYGEN SYSTEM COMPONENTS REQUIRE SPECIAL HANDLING AND PROCESSING. RETURN ANY CONTAMINATED EQUIPMENT TO VENDOR. **CAUTION:** OPEN EXPOSURE OF THE OXYGEN SYSTEM IS TO BE KEPT TO A MINIMUM. TO PROTECT THE INTEGRITY OF THE OXYGEN SYSTEM, COVER AND SEAL OPEN LINES WITH SUITABLE PLASTIC BAG, CAP, OR PLUG.

**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP**  (a), (c) 2 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Remove 1

(a), (b), (c) 2 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Install (Changed) 2

(a) Refer to 737-600/700/800/900 AMM 35-12-85 as an accepted procedure. (b) If the oxygen flex hose that attaches at the bottom of the crew oxygen mask stowage box unit is not to be connected to the new crew oxygen mask stowage box unit within 5 minutes, refer to 737- 600/700/800/900 AMM 35-00-00 and SOPM 20-70-01 as accepted procedures. (c) Refer to Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175, Rev 02 for detailed instructions.

**FIGURE 11: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 2 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 55 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 4.** 

**FIGURE 12: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 1 OF 3)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 56 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT FIGURE 12: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT**  **(SHEET 2 OF 3)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 57 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT WARNING:**  DO NOT WORK ON THE PRESSURIZED OXYGEN SYSTEM WHEN THERE IS OIL, GREASE, FLAMMABLE SOLVENTS, LINT, METAL FILINGS, OR OTHER COMBUSTIBLE MATERIALS IN THE AREA. THESE MATERIALS CAN CAUSE A FIRE OR AN EXPLOSION WHEN THEY ARE NEAR PRESSURIZED OXYGEN. REFER TO 737 MAINTENANCE MANUAL SUBJECTS 35-00-00 AND 35-12-00 AS ACCEPTED PROCEDURES. **CAUTION:** OXYGEN SYSTEM COMPONENTS REQUIRE SPECIAL HANDLING AND PROCESSING. RETURN ANY CONTAMINATED EQUIPMENT TO VENDOR. **CAUTION:** OPEN EXPOSURE OF THE OXYGEN SYSTEM IS TO BE KEPT TO A MINIMUM. TO PROTECT THE INTEGRITY OF THE OXYGEN SYSTEM, COVER AND SEAL OPEN LINES WITH SUITABLE PLASTIC BAG, CAP, OR PLUG.

**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP**  (a), (c) 2 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Remove 1

(a), (b), (c) 2 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Install (Changed) 2

(a), (c) 1 MXP147-5 CREW OXYGEN MASK STOWAGE BOX UNIT Remove 3

(a), (b), (c) 1 MXP147-5 CREW OXYGEN MASK STOWAGE BOX UNIT Install (Changed) 4

(a) Refer to 737-600/700/800/900 AMM 35-12-85 as an accepted procedure. (b) If the oxygen flex hose that attaches at the bottom of the crew oxygen mask stowage box unit is not to be connected to the new crew oxygen mask stowage box unit within 5 minutes, refer to 737- 600/700/800/900 AMM 35-00-00 and SOPM 20-70-01 as accepted procedures. (c) Refer to Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175, Rev 02 for detailed instructions.

**FIGURE 12: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 3 OF 3)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 58 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 5.** 

**FIGURE 13: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 1 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 59 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT WARNING:**  DO NOT WORK ON THE PRESSURIZED OXYGEN SYSTEM WHEN THERE IS OIL, GREASE, FLAMMABLE SOLVENTS, LINT, METAL FILINGS, OR OTHER COMBUSTIBLE MATERIALS IN THE AREA. THESE MATERIALS CAN CAUSE A FIRE OR AN EXPLOSION WHEN THEY ARE NEAR PRESSURIZED OXYGEN. REFER TO 737 MAINTENANCE MANUAL SUBJECTS 35-00-00 AND 35-12-00 AS ACCEPTED PROCEDURES. **CAUTION:** OXYGEN SYSTEM COMPONENTS REQUIRE SPECIAL HANDLING AND PROCESSING. RETURN ANY CONTAMINATED EQUIPMENT TO VENDOR. **CAUTION:** OPEN EXPOSURE OF THE OXYGEN SYSTEM IS TO BE KEPT TO A MINIMUM. TO PROTECT THE INTEGRITY OF THE OXYGEN SYSTEM, COVER AND SEAL OPEN LINES WITH SUITABLE PLASTIC BAG, CAP, OR PLUG.

**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP**  (a), (c) 2 MXP147-5 CREW OXYGEN MASK STOWAGE BOX UNIT Remove 1

(a), (b), (c) 2 MXP147-5 CREW OXYGEN MASK STOWAGE BOX UNIT Install (Changed) 2

(a) Refer to 737-600/700/800/900 AMM 35-12-85 as an accepted procedure. (b) If the oxygen flex hose that attaches at the bottom of the crew oxygen mask stowage box unit is not to be connected to the new crew oxygen mask stowage box unit within 5 minutes, refer to 737- 600/700/800/900 AMM 35-00-00 and SOPM 20-70-01 as accepted procedures. (c) Refer to Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175, Rev 02 for detailed instructions.

**FIGURE 13: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 2 OF 2)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 60 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 6.** 

**FIGURE 14: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 1 OF 3)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 61 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT FIGURE 14: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT**  **(SHEET 2 OF 3)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 62 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT WARNING:**  DO NOT WORK ON THE PRESSURIZED OXYGEN SYSTEM WHEN THERE IS OIL, GREASE, FLAMMABLE SOLVENTS, LINT, METAL FILINGS, OR OTHER COMBUSTIBLE MATERIALS IN THE AREA. THESE MATERIALS CAN CAUSE A FIRE OR AN EXPLOSION WHEN THEY ARE NEAR PRESSURIZED OXYGEN. REFER TO 737 MAINTENANCE MANUAL SUBJECTS 35-00-00 AND 35-12-00 AS ACCEPTED PROCEDURES. **CAUTION:** OXYGEN SYSTEM COMPONENTS REQUIRE SPECIAL HANDLING AND PROCESSING. RETURN ANY CONTAMINATED EQUIPMENT TO VENDOR. **CAUTION:** OPEN EXPOSURE OF THE OXYGEN SYSTEM IS TO BE KEPT TO A MINIMUM. TO PROTECT THE INTEGRITY OF THE OXYGEN SYSTEM, COVER AND SEAL OPEN LINES WITH SUITABLE PLASTIC BAG, CAP, OR PLUG.

**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP**  (a), (c) 3 MXP147-2 CREW OXYGEN MASK STOWAGE BOX UNIT Remove 1

(a), (b), (c) 3 MXP147-2 CREW OXYGEN MASK STOWAGE BOX UNIT Install (Changed) 2

(a) Refer to 737-600/700/800/900 AMM 35-12-85 as an accepted procedure. (b) If the oxygen flex hose that attaches at the bottom of the crew oxygen mask stowage box unit is not to be connected to the new crew oxygen mask stowage box unit within 5 minutes, refer to 737- 600/700/800/900 AMM 35-00-00 and SOPM 20-70-01 as accepted procedures. (c) Refer to Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175, Rev 02 for detailed instructions.

**FIGURE 14: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 3 OF 3)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 63 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 7.** 

**FIGURE 15: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 1 OF 3)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 64 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT FIGURE 15: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT**  **(SHEET 2 OF 3)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 65 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT WARNING:**  DO NOT WORK ON THE PRESSURIZED OXYGEN SYSTEM WHEN THERE IS OIL, GREASE, FLAMMABLE SOLVENTS, LINT, METAL FILINGS, OR OTHER COMBUSTIBLE MATERIALS IN THE AREA. THESE MATERIALS CAN CAUSE A FIRE OR AN EXPLOSION WHEN THEY ARE NEAR PRESSURIZED OXYGEN. REFER TO 737 MAINTENANCE MANUAL SUBJECTS 35-00-00 AND 35-12-00 AS ACCEPTED PROCEDURES. **CAUTION:** OXYGEN SYSTEM COMPONENTS REQUIRE SPECIAL HANDLING AND PROCESSING. RETURN ANY CONTAMINATED EQUIPMENT TO VENDOR. **CAUTION:** OPEN EXPOSURE OF THE OXYGEN SYSTEM IS TO BE KEPT TO A MINIMUM. TO PROTECT THE INTEGRITY OF THE OXYGEN SYSTEM, COVER AND SEAL OPEN LINES WITH SUITABLE PLASTIC BAG, CAP, OR PLUG.

**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP**  (a), (c) 4 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Remove 1

(a), (b), (c) 4 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Install (Changed) 2

(a) Refer to 737-600/700/800/900 AMM 35-12-85 as an accepted procedure. (b) If the oxygen flex hose that attaches at the bottom of the crew oxygen mask stowage box unit is not to be connected to the new crew oxygen mask stowage box unit within 5 minutes, refer to 737- 600/700/800/900 AMM 35-00-00 and SOPM 20-70-01 as accepted procedures. (c) Refer to Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175, Rev 02 for detailed instructions.

**FIGURE 15: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 3 OF 3)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 66 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT This Figure applies only to: Group 8.** 

**FIGURE 16: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 1 OF 3)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 67 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT FIGURE 16: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT**  **(SHEET 2 OF 3)**

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 68 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT WARNING:**  DO NOT WORK ON THE PRESSURIZED OXYGEN SYSTEM WHEN THERE IS OIL, GREASE, FLAMMABLE SOLVENTS, LINT, METAL FILINGS, OR OTHER COMBUSTIBLE MATERIALS IN THE AREA. THESE MATERIALS CAN CAUSE A FIRE OR AN EXPLOSION WHEN THEY ARE NEAR PRESSURIZED OXYGEN. REFER TO 737 MAINTENANCE MANUAL SUBJECTS 35-00-00 AND 35-12-00 AS ACCEPTED PROCEDURES. **CAUTION:** OXYGEN SYSTEM COMPONENTS REQUIRE SPECIAL HANDLING AND PROCESSING. RETURN ANY CONTAMINATED EQUIPMENT TO VENDOR. **CAUTION:** OPEN EXPOSURE OF THE OXYGEN SYSTEM IS TO BE KEPT TO A MINIMUM. TO PROTECT THE INTEGRITY OF THE OXYGEN SYSTEM, COVER AND SEAL OPEN LINES WITH SUITABLE PLASTIC BAG, CAP, OR PLUG.

**MORE DATA QTY**  **IDENTIFICATION NAME**  **TASK STEP**  (a), (c) 3 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Remove 1

(a), (b), (c) 3 MXP410-1 CREW OXYGEN MASK STOWAGE BOX UNIT Install (Changed) 2

(a) Refer to 737-600/700/800/900 AMM 35-12-85 as an accepted procedure. (b) If the oxygen flex hose that attaches at the bottom of the crew oxygen mask stowage box unit is not to be connected to the new crew oxygen mask stowage box unit within 5 minutes, refer to 737- 600/700/800/900 AMM 35-00-00 and SOPM 20-70-01 as accepted procedures. (c) Refer to Zodiac Services (Intertechnique) Service Bulletin MXP1/4-35-175, Rev 02 for detailed instructions.

**FIGURE 16: FLIGHT COMPARTMENT - CREW OXYGEN MASK STOWAGE BOX UNIT - REPLACEMENT (SHEET 3 OF 3)** 

BOEING PROPRIETARY - Copyright © Unpublished Work - See page 1 for details. Original Issue: December 14, 2009 737-35A1121 Revision 1 November 07, 2011 69 of 69 **BOEING SERVICE BULLETIN 737-35A1121 ALERT**  **ALERT**