(2)  
Unwanted Object Removal

 (3)  
Antiseize and Antigalling Compounds

 (4)  
Sealing Compounds

 (5)  
Gasket Lubricant

 (6)  
Stainless Steel Bolts With Decreased Pitch Diameters

 TASK 70-20-00-912-010-N00
 2. Maintenance Procedures
______________________
 A. General
 CAUTION: DO NOT USE WIRE BUNDLES, TUBES, DUCTS, AND OTHER ENGINE
_______ COMPONENTS INCORRECTLY. DAMAGE TO EQUIPMENT CAN OCCUR.
 (1)  
Use the correct ladders and platforms when you do maintenance on the engine.

 (2)  
Before you remove the parts, identify their locations for a correct installation.

 (a)  If the part is scored, burned, or has other unwanted conditions, tag the parts for an inspection or repair.

 (3)  
Replace all the gaskets, packings, and rubber parts each time you remove them.

 (a)  Make sure the new parts which are not metal (such as oil seals) show no sign of deterioration.

 (4)  
If the parts have a layer of corrosion preventive compounds, remove the compound.

 (a) Before you install a part, make sure it is fully clean.
 TASK 70-20-00-002-001-N00
 3. Unwanted Object Removal
_______________________
 A. General
 CAUTION: ALWAYS INSTALL THE DUST CAPS ON THE TUBE ENDS AND NOT IN THE
_______ TUBES. WHEN YOU INSTALL THE TUBES, MAKE SURE YOU REMOVE THE DUST CAPS FROM THE TUBES. THE CAPS CAN CAUSE A BLOCKAGE IN THE LINE.
 DO NOT PUT TOOLS, FASTENERS, OR OTHER SMALL OBJECTS BY THE JOINT BETWEEN THE REAR CASE STRUTS OF THE FAN EXIT. SMALL OBJECTS CAN FALL THROUGH THIS JOINT AND DOWN THE PORT OF THE
 2.5 BLEED VALVE.
 (1)  When you do work on the engine, you must obey these very important precautions.
 (a)  Make sure no dirt, lockwire, nuts, washers, or other unwanted material go into the engine.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
(b)  Use the correct plugs or caps to seal the open ends of the tubes.
 (2)  
When items fall into the engine, stop the assembly procedure.

 (a)  Find the fallen items.

 (3)
You can find and remove the unwanted objects with a borescope.

 B.
Standard Tools and Equipment

 (1)  
Borescope - Rigid or Flexible

 (2)  
Cable - Flexible

 (3)  
Magnet - Bar, 0.375-0.50 inch (9.5-12.7 mm) width

 (4)  
Tube - Flexible Plastic, 0.375-0.50 inch (9.5-12.7 mm) diameter

 (5)  
Vacuum - Shop

 C.
Consumable Materials

 (1)  
G00836 Tape - Adhesive, Double-Sided

 D.
Access

 (1)  
Location Zone
 412 Engine No. 1
 422 Engine No. 2
 432 Engine No. 3
 442 Engine No. 4

 E.
Procedure

 S 022-002-N00
 (1)  Remove the unwanted object with the borescope, the flexible plastic tube, and the vacuum as follows:
 (a)  
Use the tape to attach the flexible plastic tube to the side of the borescope. 1) Align the ends of the flexible plastic tube and borescope. 2) When you attach the tape, make sure the borescope stays

 flexible.

 (b)  
Use the tape to attach the free end of the flexible plastic tube to the hose of a vacuum.

 (c)  
Put the borescope through an opening in the engine and find the unwanted object.

 (d)  
Hold the unwanted object against the end of the flexible plastic tube with the vacuum. 1) Remove the borescope with the unwanted object.

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

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S 022-003-N00
 (2)  Remove the unwanted object with the borescope and magnet as follows:
 NOTE: Use this procedure, when the vacuum and the flexible
　
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