S 016-013-N00
(3)
Open the core cowl panels (AMM 71-11-06/201).
S 016-018-N00
WARNING: OBEY THE INSTRUCTIONS IN AMM 78-31-00/201 WHEN YOU OPEN THE
_______ THRUST REVERSERS. IF YOU DO NOT OBEY THE INSTRUCTIONS, INJURIES TO PERSONS OR DAMAGE TO EQUIPMENT CAN OCCUR.
(4)
Open the thrust reversers (AMM 78-31-00/201).
E.
Do the Inspection of the Compressor Bleed Control System
S 016-003-N00
(1)
Remove the No. 5 segment of the fan exit liner (AMM 72-34-03/401) to get access to the actuator for the 2.5 bleed valve.
S 216-004-N00
(2)
Visually examine the actuator for cracks.
(a) If the cracks cause fuel leakage, replace the actuator (AMM 75-32-01/401).
S 216-005-N00
(3) Visually examine the linkage of the 2.5 bleed valve for wear, damage and correct connection through two bleed duct ports found on each side of the No. 7 case strut.
(a) Use a fluorescent white light and mirror to examine the linkage connecting pins and the general condition of the linkage. 1) If there is a loose or missing pin, install a new pin. 2) If a part is worn or damaged, replace the part.
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////////////////////////A / PW4000 SERIES /747-400 / ENGINES/MAINTENANCE MANUAL ////////////////////////
(b) Visually examine the bellcrank-to-bracket pivot pins for wear or damage (Reference PW SB A75-51).
NOTE: Make sure the 2.5 bleed valve is in the fully open
____
position.
1) Inspect for missing pivot pins (2 locations).
NOTE: A missing pivot pin in either of the two locations
____ is not permitted. A missing pivot pin would cause the 2.5 bleed to stop functioning, resulting in engine operational problems. A missing pivot pin requires immediate engine removal for repair. Continue in service with a missing pivot pin is not permitted.
2) Inspect for a fractured or partly missing center pivot pin.
NOTE: Experience shows that if this pin fractures only a
____ portion of the pin will be missing. Some of the pin will remain and permit the 2.5 bleed to function. An engine with this condition can continue in service for up to 350 hours. If the pin is completely missing or it is obvious the bellcrank is no longer attached to the bellcrank bracket, the engine should be removed immediately for repair.
(c) Any amount of wear on the bleed valve or bleed duct is permitted.
NOTE: If there is any sign of wear on the bleed valve or
____ bleed duct, the wear is permitted provided the bleed valve operates normally and there are no 2.5 bleed maintenance messages.
S 216-021-N00
(4) Visually examine the seal for the 2.5 bleed valve.
NOTE: The seal is colored orange and bonded to the aft surface of
____ the 2.5 bleed valve ring. It can be examined through the 2.5 bleed ports. You cannot see the seal all the way around. Examine the areas that you can see.
(a) Use a flashlight and examine all areas of the seal that you can see.
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(b) Cut off those parts of the seal that are loose and hang out of a bleed valve slot.
NOTE: The bleed system is serviceable after loose seal
____ material is removed. The bleed system is servicealbe with any amount of missing seal material.
(c) If parts of the seal came loose and are missing, do the steps that follow: 1) Examine the forward edge of the fan exit liner segments for
damage at every "A" check until the seal is replaced. 2) If you find damage on the fan exit liner segments, inform your local Pratt & Whitney representative.
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