E.  Ensure engine fire switch (P8) panel is in NORMAL position.
F.  Place tape on periphery of start lever detent plate at fuel shutoff valve open position 2 (1.80 inch from start lever when in cutoff detent - fuel shutoff valve closed position 1) and at fuel shutoff valve closed position 2 (0.25 inch from start lever when in cutoff detent) for engine start levers (as applicable) (Fig. 501, Detail A).
4.  Test Engine Fuel Shutoff Valve Switch
A.  Close FUEL SYSTEMS, ENG 1/ENG 2 SHUTOFF VALVE circuit breakers (P6).
B.  Position engine start lever(s) at fuel shutoff valve open position 1 (IDLE DETENT). Verify that fuel shutoff valve position indicating lights illuminate bright (valves in transit) and then extinguish (valves fully open).
C.  Position engine start lever(s) at fuel shutoff valve open position 2. Verify that fuel shutoff valve position indicating lights remain extinguished.
NOTE: On airplanes with three position start detent, the start detent is not used for this test.
D.  Position engine start lever(s) at fuel shutoff valve closed position 2. Verify that engine fuel shutoff valve position indicating lights illuminate bright (valves in transit) and then dim (valves fully closed).
5.  Return Airplane To Normal Configuration
A.  Position engine start levers in fuel shutoff valve closed position 1 (CUTOFF DETENT).
B.  Remove tape inserted along periphery of start detent plate.
C.  Remove electrical power if no longer required (Ref 24-22-0 MP).
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28-22-112 Page 504  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  Jun 20/84 

FUEL LINE AND COUPLINGS - REMOVAL/INSTALLATION
1. General
A.  This procedure provides general information for removal and installation of engine fuel feed system fuel lines and fuel line couplings. This procedure includes information for Gamah and Wiggins couplings. Three types of Wiggins couplings are used: a flexible full coupling, flexible half coupling, and a rigid coupling.
B.  If a fuel line is damaged, the replacement may require that the line be cut into sections for removal and installation due to its length. Therefore, if damage exists to a line that exceeds one rib bay in length, only the damaged section should be replaced.
C.  Start connection with a rigid coupling at some fixed point like a valve, or pump fitting and observe that last connection is a flexible coupling.
D.  Do not loosen rigid coupling to facilitate installation of other couplings in the fuel line.
2.  Equipment and Materials
A.  Petrolatum - VV-P-236 (Ref 20-30-21)
B.  Solvent - BMS 3-2, Type I (Ref 20-30-31)
C.  Bonding meter (Ref 20-22-01 I/C)
D.  Gage tool - ST8709 H (optional) - E.B. Wiggins Inc., 5000 Triggs Street, Los Angeles,  CA 90022
3.  Remove Fuel Line
A.  If required, defuel applicable tank (Ref 28-23-0 MP).
B.  Purge and enter applicable tank (Ref 28-10-0 MP).
C.  If installed, disconnect bonding jumpers and keep jumper clamps for reinstallation.
D.  Loosen coupling nuts, disconnect fuel line clamps from structure, remove fuel line and clamps, and note shims or spacers for reinstallation. Discard coupling O-rings and retaining rings.
4.  Install Fuel Line (airplanes with Gamah fittings)(Fig. 401)
A.  Clean fuel line clamp mounting areas with solvent.
B.  Support fuel line with clamps loosely connected to support brackets with bolts, washers, and nuts. Do not tighten at this time.
505 
Jun 20/89  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  28-22-141 Page 401 

Fuel Line and Couplings Installation (Gamah)  505 
28-22-141  Figure 401  Oct 20/85 
Page 402 
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 

C.  Check alignment of fuel lines.
(1)  
Slide coupling nut and coupling sleeve away from fuel line ends so that flanges are exposed, and slide fuel lines toward each other until ends of flanges touch.

(2)  
Measure maximum tapered gap. Gap must not exceed tolerance given in Fig. 401.

D.  Slide coupling nut and coupling sleeve away from fuel line ends so that flanges are exposed, and install O-rings in grooves on flanges.
E.  Lightly lubricate outside of flanges and O-rings with petrolatum taking care not to get lubricant in O-ring groove or on inside diameter of O-ring.
F.  Position fuel lines so ends of lines are 0.25 to 0.33 inch apart.
　
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