General Visual Inspection (GVI) of the Temperature Indicating System [PW11]

TASK 77-21-00-210-801-A
General Visual Inspection (GVI) of the Temperature Indicating System

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AND THE ADJACENT COMPONENTS AFTER ENGINE SHUTDOWN. THE ENGINE, THE ENGINE OIL AND THE ADJACENT COMPONENTS CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS INSTRUCTION, INJURY CAN OCCUR.

ZONE: 400

1. Reason for the Job
Use this procedure to do a visual inspection of the temperature indicating system for damage (nicks, dents, corrosion, pitting and scratches), correct attachment, correct clearance and leaks.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 1M(3 FT)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
400	POWER PLANT, NACELLES AND PYLONS
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR, 451AL, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR, 461AL, 462AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-00-00-860-833-A	Procedure to Prevent Engine Motoring
TASK 71-13-00-010-802-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-802-A	Closing of the Fan Cowl Doors
TASK 73-21-24-000-801-A	Removal of the T3 Probe
TASK 73-21-24-400-801-A	Installation of the T3 Probe
TASK 77-21-00-220-801-A	Detailed Visual Inspection of the Temperature Indicating System
TASK 77-21-21-000-801-A	Removal of the Exhaust Gas Temperature (EGT) Probe
TASK 77-21-21-400-801-A	Installation of the Exhaust Gas Temperature (EGT) Probe
TASK 77-21-61-000-802-A	Removal of the Exhaust Gas Temperature (EGT) (T5/T3) Wiring Harness (WC05)
TASK 77-21-61-400-802-A	Installation of the Exhaust Gas Temperature (EGT) (T5/T3) Wiring Harness (WC05)
TASK 78-30-00-040-805-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-30-00-440-805-A	Reactivation of the Thrust Reverser System after Ground Maintenance
TASK 78-36-00-010-802-A	Opening of the Thrust Reverser Cowl-Doors
TASK 78-36-00-410-802-A	Closing of the Thrust Reverser Cowl-Doors
Temperature Indicating System

3. Job Set-up
Subtask 77-21-00-941-050-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) Do the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833).

Subtask 77-21-00-010-050-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL 448AR.
(2) Put an ACCESS PLATFORM 1M(3 FT) in position.

Subtask 77-21-00-040-050-A ** ON A/C NOT FOR ALL

C. Deactivation of the Thrust Reverser for Ground Maintenance

WARNING: YOU MUST DEACTIVATE THE THRUST REVERSER BEFORE YOU DO WORK ON OR AROUND IT. IF YOU DO NOT, THE THRUST REVERSER CAN OPERATE ACCIDENTALLY AND CAUSE AN INJURY AND/OR DAMAGE.

(1) Do the deactivation of the thrust reverser system for ground maintenance (Ref. AMM TASK 78-30-00-040-805).

Subtask 77-21-00-010-051-A ** ON A/C NOT FOR ALL

D. Get Access
(1) Open the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL 462AR.

4. Procedure
Subtask 77-21-00-210-050-A ** ON A/C NOT FOR ALL

A. General Visual Inspection (GVI) of the Temperature Indicating System

CAUTION: WIPE CLEAN ALL PARTS AND TOOLS AS NECESSARY TO REMOVE UNWANTED DEBRIS AND PREVENT DAMAGE TO THE ENGINE.

(1) Removal of individual system components can be necessary to facilitate further troubleshooting of the temperature indicating system (Ref. AMM TASK 77-21-00-220-801).
(2) Do a GVI of the temperature indicating system. See the Table 601 and the figure:

Temperature Indicating System ** ON A/C NOT FOR ALL

NOTE: The T3 probe can show signs of superficial corrosion due to tarnishing of the external surfaces . This condition is normal and does not affect the form, fit or function of the probe. Cleaning and trying to remove the tarnish is not necessary.

Table 601 - Temperature Indicating System Inspection Limits

INSPECT	DAMAGE	DISPOSITION
Harness (WC05) for:
Damage or wear	All quantities	Not permitted. Replace the harness (Ref. AMM TASK 77-21-61-000-802) and (Ref. AMM TASK 77-21-61-400-802).
Harness (WC05) connector (P43) for:
Loose condition	Looseness	Tighten (Ref. AMM TASK 77-21-61-400-802).
Damage or wear	All quantities	Not permitted. Replace the harness (Ref. AMM TASK 77-21-61-000-802) and (Ref. AMM TASK 77-21-61-400-802).
Harness (WC05) Exhaust Gas Temperature (EGT) T5 probe nuts (each end) for:
Loose condition	Looseness	Tighten (Ref. AMM TASK 77-21-61-400-802).
Harness (WC05) T3 probe nuts for:
Loose condition	Looseness	Tighten (Ref. AMM TASK 77-21-61-400-802).
T3 probe for:
Corrosion	Moderate corrosion permitted
Damage or wear	All quantities	Not permitted. Replace the probe (Ref. AMM TASK 73-21-24-000-801) and (Ref. AMM TASK 73-21-24-400-801).
T3 Probe terminal for:
Damage or wear	All quantities	Not permitted. Replace the probe (Ref. AMM TASK 73-21-24-000-801) and (Ref. AMM TASK 73-21-24-400-801).
EGT T5 probe assembly for:
Damage or wear	All quantities	Not permitted. Replace the probe (Ref. AMM TASK 77-21-21-000-801) and (Ref. AMM TASK 77-21-21-400-801).
EGT T5 probe assembly terminals for:
Damage	All quantities	Not permitted. Replace the probe (Ref. AMM TASK 77-21-21-000-801) and (Ref. AMM TASK 77-21-21-400-801).

5. Close-up
Subtask 77-21-00-410-050-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL 462AR.

Subtask 77-21-00-440-050-A ** ON A/C NOT FOR ALL

B. Do the reactivation of the thrust reverser system after maintenance (Ref. AMM TASK 78-30-00-440-805).

Subtask 77-21-00-410-051-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL 448AR.
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 03:18:52 UTC