S 588-005

 (5)  
Lower the truck into the pit or lift the airplane
 (AMM 07-11-01/201).

 S 618-122
 CAUTION: BEFORE YOU DEFLATE THE STRUT MAKE SURE THAT THE AREA BELOW THE
_______ WINGS IS CLEAR. WHEN YOU DEFLATE THE STRUT THE WING CAN LOWER MANY FEET, WHICH CAN CAUSE DAMAGE TO THE EQUIPMENT.
 (6)  Deflate the shock strut.
 WARNING: DO NOT REMOVE THE VALVE BODY UNLESS YOU DEFLATE THE SHOCK
_______ STRUT FULLY. THE AIR PRESSURE CAN BLOW THE VALVE OUT AND CAUSE INJURY TO PERSONS.
 (a)  Remove the valve cap and loosen the outer nut no more than two turns.
 NOTE: The hydraulic fluid will have bubbles immediately
____ while you decrease the pressure to the ambient. Deflate the shock strut slowly to prevent the leak of fluid through the air valve.
 (b)  Put the tray below the flow fuse (drain plug).
 S 688-007
 (7)  
When you remove all the pressure on the shock strut, remove the flow fuse and drain the fluid (AMM 32-13-02/301).

 F.
Procedure (Preferred Method)

 S 038-008
 (1)  
Remove the lower bearing assembly.

 (a)  
Put a cloth around the inner cylinder for the shock strut below the gland nut (9).

 (b)  
Lift the airplane or lower the truck until the chrome surface (approximately 11.5 inches) shows on the inner cylinder for the shock strut. 1) This permits the installation of the puller for the lower

 bearing (puller tool).
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 32-13-02
 ALL  ú ú 01A Page 807 ú Oct 18/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

 CAUTION:_______ KEEP THE GLAND NUT AND THE OUTER CYLINDER TOGETHER AS A
 SET.  IF THE OUTER CYLINDER THREADS WERE REWORKED, THE
 GLAND NUT WOULD BE UNIQUE TO THE OUTER CYLINDER.  A
 DIFFERENT GLAND NUT WILL NOT FIT THE OUTER CYLINDER
 TIGHTLY AND CAN CAUSE THE LANDING GEAR FAILURE DURING THE

 OPERATION.
 (c)  
Remove the gland nut lockplate and use the wrench adapter to loosen the gland nut (9).

 (d)  
Move the gland nut (9) down to the inner cylinder yoke.

 (e)  
Move the scraper ring down to the gland nut (9).

 CAUTION: CLEAN THE HYRAULIC FLUID FROM THE TIRES IMMEDIATELY IF THE
_______ FLUID FALL ON THE TIRES. THIS WILL PREVENT THE TIRE DETERIORATION.
 (f)  
Put a tray to catch the hydraulic fluid when you remove the lower bearing (12) and the seal retainer.

 (g)  
Connect two hydraulic jacks to the hoses and the pump.

 (h)  
Put the jacks below the truck beam jack pads.

 (i)  
Turn the higher parts of the jack until they touch the pads.

 (j)  
Make sure the base of the jack are flat with the floor.

 (k)  
Attach the puller tool to the lower bearing with three screws.

 (l)  
Install the sleeve of the puller to the chrome surface of the inner cylinder (13).

 (m)  
Move the lower bearing down to stay at the gland nut at the top of the yoke.

 (n)  
Push the follower (1) back into the outer cylinder (2).

 (o)  
Keep the follower (1) and the outer cylinder (2) with the gland nut lockplate and the screw temporarily.

 (p)  
Remove the used seal (6) from the lower bearing groove.

 (q)  
Keep the backup rings (7) for future use.

 CAUTION: WHEN CUT THE SEAL, PUT A PROTECTION STRIP BETWEEN THE SEAL
_______ AND THE SURFACE OF THE INNER CYLINDER. THIS WILL PREVENT THE DAMAGE TO THE SURFACE OF THE INNER CYLINDER. THE NICKS OR THE SCRATCHES ON THE INNER CYLINDER WILL CAUSE DAMAGE TO THE INNER CYLINDER. THEY WILL ALSO CAUSE DAMAGE TO SEALS WHILE THE SEALS MOVE THROUGH THE NICKS OR SCRATCHES.
 (r)  
Remove the backup rings (11) and cut the seal (8) from around the inner cylinder (13) on the lower bearing.

 (s)  
Use the plastic tool to prevent damage to the inner cylinder surface.

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