S 117-022
 (7)  
Do steps (5) and (6) again until the compartment and/or conveyor system equipment are clean.
S 177-023
 (8)  
Flush the compartment and/or conveyor system equipment with warm, clean water.
 NOTE: Apply the water with a mop, cloth wiper, and/or sponge, as
____ necessary.
 S 147-024
 (9)  Remove the water with a vacuum cleaner, mops, cloth wipers, and/or sponges, as necessary.
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 S 147-025
 (10) Dry all the surfaces cleaned with clean, cloth wipers.
 NOTE: Use compressed air to remove water which is caught in hard
____
 to reach areas.
 S 427-026
 (11) Install the conveyor system equipment you removed, if necessary.
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747-400 
MAINTENANCE MANUAL
COUNTERBALANCE 
STRUT  
ASSEMBLY HANDRAIL  (2 LOCATIONS)  
SEE  B  SEE  A  
LATCH  LADDER  
LEVER  TRUNNION  
SEE  C 
LADDER  FLOOR LATCH  
FOOT  
EXTENDED POSITION RETRACTED POSITION  
CREW LADDER  
UPPER  
HANDRAIL  
LADDER  
ENCLOSSURE  
(REF) 
BOLT 
WASHER 
BOLT NUT 
WASHER (2 LOCATIONS) 
BUSHING 
NUT
COUNTERBALANCE
BOLT(2 LOCATIONS)LADDER
WASHER SUPPORT STRUT 
(2 LOCATIONS)  LOWER FWDBUSHING HANDRAIL NUT (REF) 
FWD  FWD 
COUNTERBALANCE STRUT  HANDRAIL ASSEMBLY LADDER TRUNNION 
A B C 
Crew Ladder Installation 
Figure 401
C31410
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747-400 MAINTENANCE MANUAL
 CREW LADDER - REMOVAL/INSTALLATION
__________________________________
 1.  General_______
 A.  This procedure contains these tasks:
 (1)  
The removal of the crew ladder.
 (2)  
The installation of the crew ladder.
 B.  It is recommended that two or more crews are needed for the
 removal/installation of the crew ladder.
 TASK 25-50-01-004-001
 2.  Remove the Crew Ladder (Fig. 401)______________________
 A.  Equipment
 (1)  Ladder tool
 B.  Access
 (1)  Location Zone
 831L No. 1 Main Door
 C.  Procedure
 S 864-002
 (1)  
Make sure the crew ladder is in the retracted position.
S 034-003
 (2)  
Disconnect the bolts, washers, and nuts to remove the counterbalance strut from the crew ladder.
 S 044-003
 WARNING: BE CAREFUL WHEN YOU LOWER THE CREW LADDER TO THE MAIN DECK.
_______ THE CREW LADDER IS VERY HEAVY AFTER YOU DISCONNECT THE COUNTERBALANCE STRUT FROM THE CREW LADDER. IF YOU ARE NOT CAREFUL THE LADDER CAN FALL AND CAUSE INJURY TO PERSONS OR DAMAGE TO EQUIPMENT.
 (3)  
Use the ladder tool to lower the crew ladder to the main deck floor.
S 034-004
 (4)  
Remove the bolts, washers, bushings, and nuts to disconnect the upper hand rails from the lower hand rails.
S 034-005
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