TM 1-1520-238-T-7
10–253
10–100. AUXILIARY FUEL SYSTEM – MAINTENANCE OPERATIONAL CHECK (cont)
10–100
Task
Result
NOTE
If result of repeating step h. as directed by paragraph 10–105 or
paragraph 10–106 is not satisfactory, refer to TM 1-1520-238-T-5 to
troubleshoot PAS. If PAS is satisfactory, refer to TM 1-1520-238-23 to
perform fuel quantity indicator system calibration.
After EXT TK switch is set ON, fuel transfer may be delayed up to 10
minutes while external fuel tanks pressurize.
i. On pilot instrument panel, check that FWD
and AFT vertical displays on pilot FUEL
quantity indicator (fig. 10–87) show
increase.
If both vertical scales on pilot FUEL quantity indicator
do not show increase with EXT TK switch to ON, go
to paragraph 10–104.
If FWD vertical display on pilot FUEL quantity
indicator does not show increase with EXT TK switch
set to ON, go to paragraph 10–105.
If AFT vertical display on pilot FUEL quantity indicator
does not show increase with EXT TK switch set to
ON, go to paragraph 10–106.
j. With fuel transferring from external tanks,
have assistant check both wings and inside
ammo bay for leaks.
If leaks are found, replace leaking components
(TM 1-1520-238-23).
k. Continue to monitor pilot FUEL quantity
indicator until TOTAL digital readout stops
increasing.
l. On pilot caution/warning panel (fig. 10–90),
check EXT EMP indicator is lighted.
If EXT EMP indicator does not light with pilot FUEL
quantity indicator TOTAL digital readout not
increasing, replace lamp (TM 1-1520-238-23). If lamp
is still not lighted, go to paragraph 10–107.
m. On pilot FUEL panel (fig. 10–91), set EXT
TK switch to OFF.
n. On pilot caution/warning panel, check EXT
EMP indicator is not lighted.
If EXT EMP indicator is lighted with EXT TK switch
set to OFF, go to paragraph 10–108.
2. Perform FUEL SYSTEM – POWER DOWN (para 10–11).
3. Install ammo storage magazine (TM 9-1090-208-23-1).
