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747-400 MAINTENANCE MANUAL
 S 034-077
 (13) Disconnect the hydraulic hoses from the retract actuator to release the residual pressure.
 NOTE: If you do not disconnect the hoses, the retract actuator can
____ continue to extend. It can hit against the wheel well. Use a bucket to retain the fluid.
 (a)  Seal the hydraulic hoses with plugs.
 S 034-014
 (14) Disconnect the retract actuator of the nose gear from the trunnion crank arm.
 NOTE: Attach the retract actuator to the drag strut (Fig. 401).
____
 S 034-015
 (15)
 If you have to remove the trunnion bearing cap, remove the actuator bracket of the release interlock for the ground door.

 (a)  
Disconnect the release actuator of the ground door at the head and the rod ends.

 NOTE: Keep the hydraulic lines connected to the interlock
____ actuator. Attach a line to the actuator to keep the actuator away.
 (b)  Remove the 4 bolts with the washers and the nuts to remove the interlock actuator bracket.
 S 684-016
 (16)
 Deflate the shock strut of the nose landing gear.

 (a)  
Remove the air valve cap.

 WARNING: DO NOT LOOSEN THE AIR VALVE UNLESS YOU DEFLATE THE SHOCK
_______ STRUT. THE AIR PRESSURE CAN BLOW THE VALVE OUT. IT CAN CAUSE INJURY TO PERSONS.
 CAUTION: MAKE SURE THE AREA BELOW THE AIRPLANE IS CLEAR
_______ BEFORE YOU DEFLATE THE SHOCK STRUT. THIS WILL PREVENT DAMAGE TO THE EQUIPMENT WHEN THE SHOCK STRUT COMPRESSES AND THE NOSE OF THE AIRPLANE LOWERS.
 (b)  Loosen the air valve nut with two turns maximum.
 NOTE: Fluid in the shock strut will have bubbles immediately
____ while you decrease the pressure to the ambient pressure. Deflate the shock strut slowly to prevent leakage of fluid through the air valve.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
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747-400 MAINTENANCE MANUAL
 (c)  Tighten the nut and replace the cap after you deflate the shock strut.
 S 494-017
 (17)
 Install the oleo lock for the nose landing gear.

 E.
Nose Landing Gear Removal (Fig. 402)

 S 864-097
 WARNING: MAKE SURE THE STRUT IS FULLY DEPRESSURIZED BEFORE JACKING.
_______ FAILURE TO DO THIS CAN LET THE STRUT MOVE UNDER PRESSURE AND CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMENT.
 (1)  
Lift the nose of the airplane until you can put the vertical support dolly (or equivalent equipment) below the nose landing gear (AMM 07-11-02/201).

 S 494-019

 (2)  
Install special tools.

 (a)  
Align the holes on the dolly body beam with the holes on the tow lug.

 NOTE: Install the tow lug bolt.
____
 (b)
Connect the tow lug bolt with the washer and the nut.

 (c)
Tighten the nut to 180 pound-inches (20 Nm) maximum.

 CAUTION: TIGHTEN THE SPOOL A MINIMUM OF ONE AND A HALF TURNS.
_______ DO NOT USE THE RETENTION TOOL AND THE DOLLY ON A PRESSURIZED SHOCK STRUT.
 (d)  
Set the strap assembly and the retention tool.

 (e)  
Adjust the jacks to hold the gear weight equally.

 (f)  
Tighten the strap assembly and the retention tool with the ratchet buckle.

 WARNING: HOLD THE NOSE GEAR TRIPOD BEFORE YOU DISCONNECT THE DRAG
_______ STRUT FROM THE TRIPOD APEX. FAILURE TO DO THAT WILL CAUSE THE TRIPOD TO FALL WHEN YOU REMOVE THE PIN. IT WILL CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMENT.
 (g)  Hold the lower and the upper tripods for the nose landing gear.
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