2...........….................…...............................1
(e)
Pull the START switch for the applicable engine to open the PRSOV.
(f)
Look at the valve position indicator and make sure that the PRSOV is in the open position (Fig. 502, view A).
NOTE: The PRSOV must be in the open position during the test.
____
S 215-014-N00
(16) Look at the valve position indicator and make sure the shutoff valve is closed.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
75-23-00
ALL ú ú N01 Page 507 ú Jun 18/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / PW4000 SERIES /747-400 / ENGINES/MAINTENANCE MANUAL ////////////////////////
S 785-015-N00
(17)
Slowly decrease the vacuum to a minimum of 20,000 feet of altitude.
(a)
Make sure that the shutoff valve opens between 23,200 and 22,000 feet of altitude.
S 785-016-N00
(18)
Increase the vacuum to a maximum of 25,000 feet of altitude.
(a)
Make sure that the shutoff valve closes between 23,300 and 24,500 feet of altitude.
S 865-017-N00
(19)
Close the PRSOV valve:
(a)
Push the START switch for the applicable engine to the "OFF" position to close the PRSOV.
(b)
Make sure that the PRSOV is in the closed position (Fig. 502, view A).
(c)
Do this task to close the applicable access door: "Nacelle and Engine-to-Wing Fairing Access Door and Panels" (AMM 06-09-09/201). Refer to the table that follows for the correct access door:
~............................................................. | Strut | Access Door | Name of the Access Door | ...............................................................
| 1 | 452FL |Mid Lower Strut Aft Access Door|
| 2 | 462FL |Mid Lower Strut Aft Access Door|
| 3 | 472FL |Mid LOwer Strut Aft Access Door|
| 4 | 482FL |Mid LOwer Strut Aft Access Door|
2...........….................…...............................1
(d)
Open the 6J18 ENG START AIR CONT circuit breaker on the P6 main power distribution panel.
(e)
Connect the electrical connector DV351 to the receptacle on the start valve.
(f)
Close the 6J18 ENG START AIR CONT circuit breaker on the P6 main power distribution panel.
S 865-018-N00
(20)
Do this task: "Release the Pressure in the Pneumatic System" (AMM 36-00-00/201).
S 085-019-N00
(21)
Disconnect the vacuum pump line from the vent port of the barometric switch.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
75-23-00
ALL ú ú N01 Page 508 ú Jun 18/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
S 415-020-N00
(22) Do this task to close the applicable access door: "Nacelle and Engine-to-Wing Fairing Access Doors and Panels" (AMM 06-09-09/201). Refer to the table that follows for the correct access door:
~............................................................ | Strut | Access Door | Name of the Access Door | ..............................................................
| 1 | 451AR | TAI Valve Access Door |
| 2 | 461AR | TAI Valve Access Door |
| 3 | 471AR | TAI Valve Access Door |
| 4 | 481AR | TAI Valve Access Door |
2...........….................…..............................1 中國航空網(wǎng) www.k6050.com 航空翻譯 www.aviation.cn 本文鏈接地址：747-400 AMM 飛機維護手冊 大氣 AIR 1(18)
