(7)  
Solvent - Butyl carbitol (alternative to B01011, Series 91) -commerically available (AMM 20-30-91/201)

 (8)  
Solvent - B01011, Series 91 - commercially available (AMM 20-30-91/201)

 (9)  
Squeegee - commercially available

 (10)
 Wiping cloth, lint-free (commercially available)

 C. References
 (1)  AMM 36-00-00/201, Pneumatics - General
 D. Prepare for the Repair
 S 868-147
 (1)  Remove the pneumatic power (AMM 36-00-00/201).
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 (2)  S 868-148On the bleed air control module on the pilots' overhead panel, put the pack control switches in the OFF position.
 (3)  S 018-149Remove the applicable ceiling, sidewall, or floor panels to gain access to the damaged air conditioning duct.
 (4)  S 028-150If insulation is installed on the duct joint, remove the insulation.
 (5)  S 348-151Examine the inner surface of the duct for damage.
 NOTE:____ If the inner lining is damaged, do the procedure to replace a section of rigid foam duct.
 (6)  S 348-152Examine the damage to the duct.
 NOTE:____ If the damage is more than half the thickness of the foam duct material, do the procedure to replace a section of rigid foam duct.
 (7)  S 348-153Do these steps to prepare the air conditioning duct:
 WARNING:_______ DO NOT GET SOLVENTS IN YOUR MOUTH, OR IN YOUR EYES, OR ON YOUR SKIN. DO NOT BREATHE THE FUMES FROM SOLVENTS. SOLVENTS ARE HAZARDOUS MATERIALS. SOLVENTS MAY BE FLAMMABLE OR HARMFUL TO THE ENVIROMENT. REFER TO PRODUCT MATERIAL SAFETY DATA SHEETS (MSDS) AND LOCAL REQUIREMENTS FOR PROPER HANDLING PROCEDURES.
 (a)  Use the solvent and a wiping cloth to clean the damaged area.

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747-400 MAINTENANCE MANUAL
 (b)  
Sand the duct outer surface a minimum of 2-inches from the edges of the damaged area to remove any remaining adhesive and contamination.

 (c)  
Use the solvent and a wiping cloth to clean the damaged area.

 S 348-154
 (8)  Cut a piece of rigid foam to fit the area where the damaged foam was removed.
 NOTE: Put the foam in the opening to make sure it is the correct
____
 size and shape.

 S 348-155
 (9)  Prepare the Fiberglass cloth:
 (a)  
Cut two pieces of fiberglass cloth 2 inches larger on all sides than the damaged area.

 (b)  
Round the corners of the Fiberglass cloth pieces.

 S 348-156
 (10) Prepare the potting compound.
 E. Repair the Duct
 S 348-157
 (1)  
Apply potting compound to the area where the rigid foam was removed.

 S 348-158

 (2)  
Put the piece of rigid foam in the area where the damaged foam was removed.

 S 348-159

 (3)  
Put a piece of plastic sheet on the piece of rigid foam and press on it to align the surface of the piece with the surface of the duct.

 S 168-160
 WARNING: DO NOT GET SOLVENTS IN YOUR MOUTH, OR IN YOUR EYES, OR ON YOUR
_______ SKIN. DO NOT BREATHE THE FUMES FROM THE SOLVENTS. SOLVENTS ARE HAZARDOUS MATERIALS. SOLVENTS MAY BE FLAMMABLE OR HARMFUL TO THE ENVIROMENT. REFER TO PRODUCT MATERIAL SAFETY DATA SHEETS (MSDS) AND LOCAL REQUIREMENTS FOR PROPER HANDLING PROCEDURES.
 (4)  Remove any unwanted resin from the edges of the piece of rigid foam with a wiping cloth soaked with the solvent.
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