S 766-010-N00
(9) With a low voltage ohmmeter, touch one test prod on the terminal stud of the alumel circuit A and the other test prod on the terminal stud of the chromel circuit A to examine the insulation resistance between the conductors.
(a) Make a record of the insulation resistance value.
S 766-011-N00
(10)
Do the insulation resistance check for circuit B on the same EGT thermocouple cable.
S 766-012-N00
(11)
Do the insulation resistance check for circuit A and circuit B for the other EGT thermocouple cable.
(a) If an insulation resistance value goes below 50,000 ohms, replace the EGT thermocouple cable (AMM 77-21-02/401).
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S 766-026-N00
(12) To do a check for short circuits in the EGT thermocouple cable, do the steps that follow:
(a)
Set the ohmmeter range switch to the range which has a center scale value of 10 ohms.
(b)
Touch the test prods on terminal studs with the same steps before in the insulation resistance check.
(c)
If movement occurs, but do not include when you accidentally touch the other terminals, replace the EGT thermocouple cable (AMM 77-21-02/401).
S 436-014-N00
CAUTION: DO NOT PUT MORE THAN THE MAXIMUM TORQUE ON THE NUTS WHICH
_______ ATTACH THE HARNESS LEADS. IF YOU TIGHTEN THE NUTS TOO MUCH, THE NUTS CAN LOOSEN OR DAMAGE TO THE STUDS CAN OCCUR.
(13) Connect the left and right EGT thermocouple and harness leads for the EEC thermocouple cable to the applicable terminal box studs.
(a) Attach the harness leads with the applicable nuts and tighten the nuts with the steps that follow: 1) Tighten the nuts attached to the alumel (larger diameter)
studs to 18-22 pound-inches (2.0-2.5 newton-meters). 2) Tighten the nuts attached to the chromel (smaller diameter) studs to 15-18 pound-inches (1.7-2.0 newton-meters).
S 436-015-N00
(14) Install the cover on the terminal box with the steps that follow:
(a) Put the cover and the inner and outer clamp halves on the terminal box. 1) Make sure the ground lead for the EEC harness aligns
between the terminal box and cover.
NOTE: If the ground lead on the W6 cable at the EGT
____ Thermocouple Terminal Box is damaged or missing, you must repair the cable per Unison SB 420081-73-46 or replace it.
2) Make sure the left and right EGT thermocouple cable halves align between the clamp halves.
(b)
Lubricate the threads of the screws with engine oil.
(c)
Install the screws to the terminal box.
(d)
Tighten the screws to 16-22 pound-inches (1.8-2.5
newton-meters).
S 436-028-N00
(15) Connect the harness leads for the EGT thermocouple cable to the applicable probe studs with the nuts and washers.
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////////////////////////A / PW4000 SERIES /747-400 / ENGINES/MAINTENANCE MANUAL ////////////////////////
S 436-018-N00
CAUTION:_______ DO NOT PUT MORE THAN THE MAXIMUM TORQUE ON THE NUTS WHICH
ATTACH THE HARNESS LEADS. IF YOU TIGHTEN THE NUTS TOO MUCH,
THE NUTS CAN LOOSEN OR DAMAGE TO THE STUDS CAN OCCUR.
(16) Tighten the nuts with the steps that follow:
(a)
Tighten the nuts attached to the alumel (larger diameter) studs to 18-22 pound-inches (2.0-2.5 newton-meters).
(b)
Tighten the nuts attached to the chromel (smaller diameter) studs to 15-18 pound-inches (1.7-2.0 newton-meters).
S 416-021-N00
(17)
Close the core cowl panels (AMM 71-11-06/201).
S 446-029-N00
(18)
Do the activation procedure for the thrust reverser (AMM 78-31-00/201).
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本文链接地址：747-400 AMM 飞机维护手册 发动机指示 ENGINE INDICATING(44)
