TM 55-1520-240-23-8
10-27
TEST FORWARD FUEL TANK AFTER INSTALLATION
(Continued)
10-27
5.
Make sure valves (16 and 17) are closed.
Connect test setup to fitting (7).
Structural damage to aircraft may
occur if more than 4.0 psi is applied.
6.
Open valve (16) and apply 3.0 psi. Close valve.
Do not apply more than 4.0 psi.
7.
Wait 15 minutes. Check gage (18). If gage
indicates 3.0 psi, go to step 16. If gage indicates
less than 3.0 psi, go to step 8.
CHECK FOR LEAKS OUTSIDE TANK
8.
Check for leaks as follows:
a.
Check test setup upstream and downstream
of valves (16 and 17) and gage (18). Use
mixture of soap (E353) and water and
brush (E85). Allow system to remain under
measure for 15 minutes. If bubbles grow
in size, connection is leaking. Tighten
leaking connections or replace packings as
needed. Also check all joints, seams, and
cast components. If leak is found, repeat
steps 6 and 7.
b.
Check three fittings (19). Apply soap mixture
as in step 8a. Secure fittings or replace
packings if needed. If leak is found, repeat
steps 6 and 7.
c.
Check aft access door (20). Apply soap
mixture as in step 8a. Secure access door or
replace gaskets, if needed. If leak is found,
repeat steps 6 and 7.
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