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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / PW4000 SERIES /747-400 / ENGINES/MAINTENANCE MANUAL ////////////////////////
E. Procedure
 S 027-002-N00
 (1) Remove the EGT (TT4.95) thermocouple probe (AMM 77-21-01/401).
 S 117-003-N00
 WARNING: MAKE SURE YOU USE THE SOLVENT IN AN AREA THAT HAS A GOOD FLOW
_______ OF AIR. DO NOT PERMIT THE SOLVENT TO TOUCH YOUR SKIN. THE SOLVENT IS VERY FLAMMABLE.
 CAUTION:_______DO NOT USE TOO MUCH SOLVENT ON THE THERMOCOUPLE PROBE. TOO MUCH SOLVENT ON THE THERMOCOUPLE PROBE WILL PERMIT THE SOLVENT TO BE ABSORBED BY THE INSULATION IN THE PROBE. SOLVENT IN THE PROBE CAN CAUSE THE PROBE TO OPERATE INCORRECTLY.
 (2)  To remove the unwanted material from the EGT thermocouple head, do these steps:
 (a)  
Put solvent on the cloth.

 (b)  
Clean the EGT probe head with a brush and solvent.

 (c)  
Rub the EGT probe head with the cloth.

 (d)  
Dry the EGT probe with compressed air at 30 psi (200 kPa) maximum.

 S 167-004-N00
 (3)  
Remove the loose carbon material from the EGT thermocouple sheath with compressed air at approximately 100 psi (700 kPa) maximum.

 S 117-005-N00

 (4)  
To remove the hard carbon material from the EGT thermocouple sheath, do these steps:

 (a)  
Clean the EGT thermocouple sheath with a brush and solvent.

 (b)  
Put solvent on the cloth.

 (c)  
Rub the EGT thermocouple sheath with the cloth.

 (d)  
Dry the EGT thermocouple sheath with compressed air at 30 psi (200 kPa) maximum.

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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
S 427-006-N00
 (5) Install the EGT (TT4.95) thermocouple probe (AMM 77-21-01/401).
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
EXHAUST GAS TEMPERATURE (TT4.95) THERMOCOUPLE CABLE -
_____________________________________________________ REMOVAL/INSTALLATION
____________________
 1.  General_______
 A.  In this procedure, the exhaust gas temperature (EGT) (TT4.95)
 thermocouple cables are referred to as the thermocouple cables.

 B.  In this procedure, the exhaust gas temperature (EGT) (TT4.95)
 thermocouple probes are referred to as the thermocouple probes.

 C.  In this procedure, the exhaust gas temperature (EGT) (TT4.95) thermocouple cable terminal box is referred to as the terminal box.
 D.  This procedure has two tasks:
 (1)  
The first task gives instructions to remove the exhaust gas temperature (EGT) thermocouple cables.

 (2)  
The second task gives instructions to install the exhaust gas temperature (EGT) thermocouple cables.

 E.  
The left thermocouple cable connects two thermocouple probes on the left half of the turbine exhaust case to the terminal box. These thermocouple probes are installed at the 7 and 10 o'clock positions on the turbine exhaust case.

 F.  
The right thermocouple cable connects two thermocouple probes on the right half of the turbine exhaust case to the terminal box. These thermocouple probes are installed at the 1 and 4 o'clock positions on the turbine exhaust case.

 G.  
You must open the core cowl panels to get access to the thermocouple probes.

 TASK 77-21-02-004-001-N00
 2.  Remove the Exhaust Gas Temperature (TT4.95) Thermocouple Cables_______________________________________________________________
 A.  References
 (1)  
AMM 27-62-00/201, Speed Brake Control System

 (2)  
AMM 71-11-06/201, Core Cowl Panels

 (3)  
AMM 78-31-00/201, Thrust Reverser System
　
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