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 52-31-01
 ALL  ú ú 02 Page 409 ú Oct 18/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

 S 224-019
 (3)  Make sure the allowable wear on the structural attach fittings is in
 the limit.
 S 224-020
 (4)  If you install the used hinge bolts, make sure the allowable wear on
 the bolts is in the limit (AMM 52-31-01/601).
 S 214-021
 (5)  Do a visual check of the adjustable fairing and seal to make sure
 that there is no possible interference when the door is closed (AMM
 52-31-00/501).
 S 494-022
 (6)  Attach lift brackets to the nose cargo door.
 (a) Remove 44 countersunk screws and plugs from sling attachment
 points.
 (b) Install two loose stud pads on door with supplied bolts.
 (c) Make sure to install the inner nut and washer down to the stud
 as far as possible.
 (d) Install lift bracket (with third pad) over two stud pads.
 1) Put the bolts through the third pad and in the door.
 (e) Install the outer nut and washer on two studs.
 (f) Tighten the inner and outer nuts against the lift bracket.
 S 494-023
 (7)  Attach sling to the nose cargo door and crane as shown in Fig. 402.
 (a) Install the sling over the door.
 (b) Attach the cables from the sling to the lift brackets.
 S 864-024
 (8)  Slowly lift the door with crane to support the door weight and
 remove the cable slack.
 (a) Make sure the door weight distributes equally on each lift
 cable.
 NOTE: The door is now at the 15 degree open position for door____
 installation.

 S 164-025
 (9)  
Clean the hinge bolts and hinge bearings and all latch fittings and bearings.

 S 644-026

 (10)
 Lubricate the hinge bolts and hinge bearings and all latch fittings and bearings.

 S 034-027

 (11)
 Remove the door safety barrier, if it was installed.

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 S 864-028
 (12)
 Make sure these circuit breakers are opened:

 (a)  
On the Auxilary External 2 Power Center-Right panel P715: 1) NOSE CARGO DOOR

 (b)  
On the Power Distribution Center-Right panel P415: 1) 415F16, NOSE CARGO DOOR CONTROL

 (c)  
On the Nose Cargo Door Power panel H122:
 1) DOOR LIFT
 2) PULL UP CAM
 3) LATCHES 1-4R
 4) LATCHES 1-4L
 5) LATCHES 5-8R
 6) LATCHES 5-8L

 G.
Nose Cargo Door Installation

 S 824-005
 CAUTION: DO NOT ALLOW DOOR TO OSCILLATE THE LIFT CABLES MORE THAN | 5
_______ DEGREES FROM THE VERTICAL. THIS CAN CAUSE DAMAGE TO THE LIFT FITTINGS ON THE ATTACHMENT PADS.
 (1)  
Use crane to lift the door to align the nose cargo door hinges with the hinge bearings on the body structure.

 S 424-064

 (2)  
Install the shims on each side of the hinge bearings in the same positions they were removed from.

 S 434-030

 (3)  
Install the large hinge bolts through the hinge and hinge bearing holes.

 (a)  
Install the thread protectors on the bolts.

 (b)  
Align the hinges and the hinge bearings to make sure you can install the bolts freely.

 (c)  
Install the bolts through the hinge bushings, hinge bearings and shims.

 (d)  
Remove the thread protectors from the bolts.

 (e)  
Install the large nuts and washers on the bolts and torque the nuts to 30 - 35 pound-inches to make sure that the bolts will stay in place.

 S 494-031
 (4)  
Install the forward spreader beam on crane:
　
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