737 AMM 飞机维护手册燃油 FUEL(187)_航空信息_民用航空_通用航空

28-41-101 Sep 01/02 Page 606

5. FQIS, Center Tank - Inspection
A. References
(1)
AMM 28-10-0/201, Fuel Tanks

(2)
AMM 28-11-31/401, Integral Center Tank Access Panel

(3)
DWG 65-48411, WING CENTER SECTION STA 540 - 663.76

B. Procedure
(1) For the center fuel tank, do these steps:
(a)
Remove the access panel for the center tank (AMM 28-11-31/401).

(b)
Go into the center tank (AMM 28-10-0/201).

(c)
Do this task for all FQIS wiring and components in the center tank: FQIS Wiring and Component Visual Inspection. 1) Refer to drawing 65-48311 for wiring and component locations.

(d)
If access is not necessary for subsequent tasks, install the access panel for the center tank (AMM 28-11-31/401).

Sep 01/02 28-41-101 Page 607

FUEL TANK BULKHEAD (SPAR) RECEPTACLE WIRE HARNESS - APPROVED REPAIRS
1. General
A. This section contains a procedure for recrimping the in-tank wire harness terminal lugs. Recrimping may be required to provide a tighter lug connection to the wire to assure electrical continuity within the fuel quantity indicating system.
2. Equipment and Materials
A. AMP hand-crimping tool - P/N 59250 or 59170
3. Recrimp Fuel Tank Wire Harness Terminal Lug
A. Defuel airplane or defuel applicable fuel tank only, and drain sump fuel (Ref 28-23-0 MP).
B. Remove fuel tank access panels.
(1)
For the wing tank remove underwing access panels 1, 2, 3, 4, 5, 7, 9, and 10 (Ref 28-11-11 R/I).

(2)
For the center tank, remove the center tank access panel (Ref\28-11-31 R/I).

C. Purge applicable fuel tank (Ref 28-10-0 MP).
D. Enter applicable tank to gain access to fuel compensator.
E. Disconnect harness terminal leads from compensator.
F. Loosen or remove harness clamps as necessary to provide length of slack wire.
G. Remove the captive screw and lockwasher from terminal tongue on the HI-Z wire lead. Retain for installation.
H. Recrimp the wire harness terminal lug using the AMP hand tool and crimping dies. Verify that end of terminal lug barrel has been deformed by the tool.
I. Install the captive screw and lockwasher on the terminal tongue.
J. Repeat steps G. thru I. for recrimping for LO-Z wire lead.
K. Connect leads and tighten clamp on unit. Tighten screws/nut to following torque ranges:
HI-Z lead (COAX) 15-16 pound-inches LO-Z lead (TANK) 19-23 pound-inches Strain relief clamp 7-9 pound-inches
L. Install and/or tighten any wire harness clamps removed or loosened.
M. Repeat steps E. thru L. for each tank unit.
N. Install fuel tank access panels as applicable (Ref 28-11-11 R/I, 28-11-31\R/I).
O. Perform fuel quantity indicating system adjustment/test (Ref\28-41-0\A/T, 28-41-05\A/T).
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Jun 20/89 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 28-41-101 Page 801

CAPACITANCE TRIM UNIT - REMOVAL/INSTALLATION
EFFECTIVITY
Airplanes with Precalibrated Indicators
1. General
A. A capacitance trim unit is used to adjust the airplane empty dry capacitance to a standardized value. This adjustment allows for replacement of fuel quantity indicators without recalibrating the indicator. The unit consists of a shielded variable capacitor with a range of 2-30 pico farad (pf).
2. Remove Capacitance Trim Unit
A. Open QTY and EP GRD FUELING circuit breakers on P6 panel.
B. Remove three screws from capacitance trim unit mounting bracket located on the forward left side of the control stand above the pilots hand mike jack (Fig. 401).
C. Withdraw capacitance trim unit from control stand and locate splice.
D. Cut wires at convenient point near splice allowing sufficient wire length to make new splice.
E. Tag wires for identification and remove capacitance trim unit.
3. Install Capacitance Trim Unit
A. Connect capacitance trim unit wires to matching tagged airplane wires using multiple wire shield splices (Ref 20-30-12, Wiring Practices Manual).
B. Insert capacitance trim unit into side of control stand panel (Fig. 401).
C. Position capacitance trim unit mounting bracket and install mounting screws.
D. Close QTY and EP GRD FUELING circuit breakers on P6 panel.
E. Perform adjustments of related components (Ref 28-41-05 A/T).
5C8
Jun 20/89 28-41-121 Page 401
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.