(c)  
Make the sealant smooth around the fastener after the installation.

 S 392-073
 (3)  Seal the fasteners that have metal covers as follows:
 (a)  
Fill the metal cover between 1/2 to 2/3 full of sealant.

 (b)  
Push the metal cover down on the fastener until the flange touches the structure.

 (c)  
Remove the unwanted sealant from the top of the metal cover.

 (d)  
Make the sealant smooth around the base of the metal cover.

 D. Fastener Sealing for Corrosion Prevention
 S 102-115
 (1)  
Clean the surface, do Prepare for Sealing.

 S 392-117

 (2)  
Procedure 1 - corrosion protection below the head area of the fastener:

 (a)  
Apply sealant to all surfaces and coutersinks below the fastener head.

 (b)  
Install the fastener.

 (c)  
A continous extrusion of sealant is necessary around the fastener.

 (d)  
Clean off unwanted sealant.

 S 392-116
 (3)  Procedure 2 - corrosion protection below the head area and shank of the fastener:
 (a)  Apply sealant to the entire shank and thread of the fastener.
 NOTE: Apply sealant to the shank only for fasteners which will
____ use self-sealing nuts or collars.
 (b)  Install fastener and nut or collar.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

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747-400 MAINTENANCE MANUAL
 (c)  Clean off unwanted sealant.
 S 392-118
 (4)  Procedure 3 - corrosion protection below the head area and shank of the fastener and the bottom attaching hardware:
 (a)  
Apply sealant to the entire shank and thread of the fastener.

 (b)  
Install fastener.

 1)  A continous extrusion of sealant is necessary around the base of the washer, if used under the fastener head.
 NOTE: More sealant can be applied to the shank of
____ the installed fastener to get the necessary sealant extrusion.
 (c)  
Install the nut or collar.

 (d)  
A continuous extrusion of sealant is necessary around the fastener head, the washer (if used), and the bottom of the nut or collar.

 S 392-119
 (5)  Apply fillet-seal to the installed fastener.
 (a)  Use class A or class B (brushable) sealants.
 NOTE: Brush marks are permitted if the fillet-seal dimensions
____
 are met.

 TASK 51-31-01-392-074
 9.  Aerodynamic Smoother Application
________________________________
 A.  Equipment
 (1)  
Sealant Removal Tool - made from wood or
 plastic 3/16 inch thick, 8 inches long in 1/4,
 1/2 and 3/4 inch widths.

 (2)  
Spatula made of wood or plastic

 (3)  
Sealing gun and nozzles

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

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MAINTENANCE MANUAL

 B. Consumable Materials
 (1)  G00138 Masking Tape - Permacel No. 70 or 85,
 American Tuck No. 210

 C. References
 (1)  AMM 51-41-00, Airframe Drainage
 D. Procedure
 S 302-075
 (1)  
Do the Prepare for Sealing task.

 S 952-076

 (2)  
Apply the masking tape to the surface that is adjacent to the damaged area.

 S 392-077
 CAUTION: DO NOT CAUSE A BLOCKAGE WHEN YOU APPLY SEALANT NEAR OR AROUND
_______ THE FUSELAGE DRAIN HOLES, TUBES, OR PATHS. THE FUNCTION OF THE DRAIN HOLES IS TO DRAIN CONDENSATION AND FLUIDS OVERBOARD. IF YOU CAUSE A BLOCKAGE, FLUIDS WILL COLLECT IN THE AIRPLANE. THE FLUIDS CAN CAUSE CORROSION TO THE STRUCTURE, OR A FIRE IF THE FLUIDS ARE FLAMMABLE.
　
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