20-10-31
ALL ú ú 01 Page 201 ú Jun 20/93
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
757 MAINTENANCE MANUAL
C. Procedure
S 112-002
(1)
Remove all dirt and grease for a minimum of one inch adjacent to the area you will seal. Use a cloth made moist with Naphtha.
S 872-003
(2)
Apply primer to the area you will seal. Use the primer specified in Table 1 for the sealant you will use.
S 392-004
CAUTION: DO NOT SEAL THE SHANK OF LAMP TERMINALS THAT ARE A
_______ SPRING-LOADED PART OF THE BAYONET LAMP SOCKET BASE. SEAL ONLY THE TERMINAL END AND ATTACHED HARDWARE. SEALANT ON THE SHANK LIMITS MOVEMENT OF THE LAMP CONTACT WHICH CAN CAUSE THE LIGHT ASSEMBLY TO BECOME TOO HOT. IF IT BECOMES TOO HOT, A FAILURE CAN OCCUR.
(3)
Use a brush to apply one layer of sealant to the open areas. Make sure you seal all the open areas.
S 392-005
(4)
On ring torque terminals, apply sealant as follows:
(a)
Apply sealant to the side of the terminal which a metal object can hit if it falls (Fig. 202).
NOTE:____Seal each terminal as far as the attached hardware. You can fully seal the attached hardware. If there are barriers between phases or between components, the seal must extend into the space given protection by the barriers.
(b)
If the edges of the terminals are less than 0.5 inch from each other, apply sealant to the edges.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
20-10-31
ALL ú ú 01 Page 202 ú Jun 20/93
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
757 MAINTENANCE MANUAL
WHEEL WELL PRESSURE BULKHEAD
NOSE WHEEL WELL
LEADING EDGE AREA TRAILING EDGE AREA
ENGINE COWL ENGINE STRUT
FUEL VAPOR AREAS:
Fuel Vapor Areas Figure 201
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
20-10-31
ALL ú ú 01 Page 203 ú Jun 20/93
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
757
MAINTENANCE MANUAL
SEAL ALL OPEN METAL ON THIS SIDE
Sealant Installation on Ring Tongue Terminals
Figure 202
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
20-10-31
ALL ú ú 01 Page 204 ú Jun 20/93
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
757 MAINTENANCE MANUAL
COAXIAL CABLE - MAINTENANCE PRACTICES
_____________________________________
1. General_______
A. The maintenance procedures that follow are applicable to all of the antenna coaxial cable trouble-shooting in Chapters 23 and 34. A Time Domain Reflectometer (TDR) is used. (The ADF system uses a shielded pair wire for each sense and loop antenna. Use the same trouble-shooting procedures for these wires as used for the coaxial cables.) Do the applicable tests and problem analysis procedures to make sure a line replaceable unit (LRU) is not defective. Also, do the necessary tests to make sure the system problem is in the antenna system.
B. The TDR uses pulses to do a test of the cables and gives a visual display of cable failures. The test pulses are transmitted through the CABLE output jack. The same jack receives the reflections and shows them on the Cathode-Ray Tube (CRT).
C. With calibrated distance controls, you can examine up to 100 feet of a cable. You can show cable lengths as short as 1 foot horizontally across the 10-division CRT display. You can examine low-loss cables up to 2000 feet (500 meters) long at 100 or 200 feet for each division. The horizontal CRT scale is calibrated directly in distance units from 0.1-200 feet for each division in a 1-2-5 sequence.
D. A 3-number display shows the distance to a cable failure when you use the display to horizontally set the failure's reflection to a CRT reference line.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：757 AMM 飞机维护手册 STANDARD PRACTICES - AIRFRAME(78)
