![]() 737-600/700/800/900 Fault Isolation Manual 故障隔离手册 |
808.
Engine Takeoff Thrust is Low - Fault Isolation |
A. Description 描述 |
(1)
The engines takeoff thrust was too low, the other engine parameters were normal for N1. |
B.
Possible Causes |
NOTE:
Regulator is a parameter that provides information as to how the Engine Control System is governing the engine speed. The regulator is available through input monitoring. Regulator values other than 3 and 9 are possible. |
(1)
Regulator = 3 |
(a) TRA Adjustment TRA调整 |
(b)
TRA Resolver, M1819 Eng 1, M1822 Eng 2 |
(c) EEC, M1818 (c) 欧洲经济共同体,M1818 |
(2)
Regulator = 9 |
(a) PS3 system PS3系统 |
(b) Fuel Pump 燃油泵 |
(c) HMU, M1823 (c) 联系我,M1823 |
(d)
Bleed Air System |
(e) VSV (e) VSV |
(f) VBV (f) VBV |
C.
Circuit Breakers |
(1)
For Engine 1; |
(a)
These are the primary circuit breakers related to the fault: |
CAPT Electrical System Panel, P18-2 |
|
(2)
For Engine 2; |
(a)
These are the primary circuit breakers related to the fault: |
F/O Electrical System Panel, P6-2 |
|
D.
Related Data |
(1)
Component Locator, (73-05 TASK SUPPORT Figure 301) |
(2) (SSM 75-31-12) (SSM 75-31-12) |
(3) (SSM 75-31-22) (3) (SSM 75-31-22) |
(4) (WDM 73-22-11) (4)(WDM 73-22-11) |
(5) (WDM 75-31-12) (5)(WDM 75-31-12) |
(6) (WDM 75-31-22) (6)(WDM 75-31-22) |
E.
Fault Isolation Procedure |
(1)
Do this task: EEC BITE Procedure, 73-00 TASK 801. |
(a)
Do the fault isolation for the INTERNAL EEC, PS3, HMU (FMV), TRA, VSV, or VBV maintenance messages that you find. |
1)
Do the Repair Confirmation at the end of this task. |
a)
If the Repair Confirmation is not satisfactory, then continue. |
(b)
If you do not find the maintenance messages, then continue. |
(2)
OPTION 1, FOR ENGINES WITH EEC S/W 1853M78P13 and ON; |
Start the applicable engine and let it idle during the steps that follow. do this task: Start the Engine Procedure (Normal Start), AMM TASK 71-00-00-800-808-F00 |
(a)
Get access to the applicable input monitoring screen on the flight management computer/control display unit (FMCS CDU): |
1)
Push the INIT REF key two times. |
2)
Push the INDEX line select key (LSK). |
NOTE:
This causes the INIT REF INDEX to show. |
3)
Push the MAINT LSK. |
NOTE:
This causes the MAINT BITE INDEX to show. |
4)
Push the ENGINE LSK. |
NOTE:
This causes the ENGINE/EXCEED BITE INDEX to show. |
5)
Push the line select key the applicable Engine, ENGINE 1 or ENGINE 2. |
NOTE:
There will be a short delay while the screen shows INITIALIZING EEC X (X = 1 or 2). Then the ENGINE BITE TEST MAIN MENU will show. |
6)
Push the INPUT MONITORING LSK. |
NOTE:
This causes the ENGINE BITE TEST INPUT MONITORING 1/2 to show. |
7)
Push the NEXT key to get access to the ENGINE BITE TEST INPUT MONITORING 2/2 screen. |
8)
Push the DISCRETES LSK |
NOTE:
This causes the ENGINE BITE TEST INPUT MONITORING 1/3 GMM DISCRETES to show. |
(b)
Make a note of the value that is listed to the right of REGULATOR. |
NOTE:
Regulator is the first item listed on the ENGINE BITE TEST INPUT MONITORING 1/3 GMM DISCRETES page. Regulator values other than 3 and 9 are possible. |
1)
Do this task: Stop the Engine Procedure (Usual Engine Stop), AMM TASK 71-00-00-700-819-F00. |
2)
If the REGULATOR equals 3, then the engine is controlled by the requested power setting. |
a)
The most likely cause of the problem is the TRA System |
b)
Do the adjustment of the thrust lever listed below first. |
3)
If the REGULATOR equals 9, then the engine is limited by the fuel flow or the PS3. |
a)
The most likely cause of the problem is the PS3, the Fuel Pump, the Fuel Metering Valve in the HMU, the Bleed Air System, the VSV, or the VBV. |
b)
Do the corrective action PS3 and the Fuel Pump listed below first. |
4)
If the REGULATOR equals a value that is not 3 or 9, then do the corrective action for REGULATOR equals 3 and 9 listed below. |
(3)
OPTION 2, FOR ENGINES WITH ALL EEC S/W PART NUMBERS; |
Do the corrective actions for REGULATOR equals 3 and 9 listed below. |
(4)
REGULATOR EQUALS 3; |
do this task: Thrust Lever Adjustment and Thrust Reverser Position Adjustment Test, AMM TASK 73-21-00-700-806-F00 |
(a)
If you find a problem, then adjust the thrust lever, and then, do this task: Engine 1 and Engine 2 Thrust Lever Angle Resolver Alignment Test, AMM TASK 73-21-00-700-807-F00. |
1)
If it was necessary to adjust the thrust lever angle resolvers during the tests, then do the Repair Confirmation at the end of this task. |
a)
If the Repair Confirmation is not satisfactory, then continue. |
(b)
If you do not find a problem, then continue. |
(5)
REGULATOR EQUALS 9; |
Examine the PS3 line for signs of a blockage, obvious damage, and loose connections. |
(a)
If you find a problem, then repair or replace the line. |
1)
Do the Repair Confirmation at the end of this task. |
2)
If the Repair Confirmation is not satisfactory, then continue. |
(b)
If you do not find a problem, then continue. |
(6)
REGULATOR EQUALS 9; |
Examine the fuel pump: |
(a)
Do this task: The Visual Inspection of the Impeller Rotation, AMM TASK 73-11-01-200-801-F00. |
Do not operate the engine as directed in the Lubrication Flow Screen Installation Test. |
1)
Make sure that the N2 rotor turns freely and smoothly as you do the fuel pump impeller inspection. |
a)
If the N2 rotor does not turn freely and smoothly, then replace the engine. These are the tasks: |
2)
If the fuel pump impeller inspection is not satisfactory, then replace the fuel pump. These are the tasks: |
3)
If you do not find a problem, then continue. |
(b)
Replace the fuel filter. These are the tasks: |
(c)
Replace the EEC. These are the tasks: |
1)
Do the Repair Confirmation at the end of this task. |
F.
Repair Confirmation |
(1)
If it is necessary, do this task: Close the Fan Cowl Panels, AMM TASK 71-11-02-410-801-F00. |
(2)
Do this task: Test 5 - Power Assurance Check, AMM TASK 71-00-00-700-813-F00. |
(a)
If the engine operation is satisfactory, then you corrected the fault. |