Service difficulty report · Tank Unit · Boeing 7377H4

Difficulty date
July 24, 2026
Submitted
July 29, 2026
Operation
Air carrier
Aircraft
N250WN
Make and model
Boeing 7377H4
Aircraft serial
34972
Aircraft time
65,186 hours, 39,629 cycles
Part
Tank Unit
Part number
202000210
Part serial
BN786420
Condition
Leaking
Location
Zn 600
Stage of operation
CL
How discovered
O
Nature of condition
K
Precautionary procedure
E

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

INFLIGHT NR 2 FUEL IMBALANCE CLIMBING THROUGH FL 250, NOTICED NR 2 FUEL QTY DECREASE BELOW NR 1 ENGINE QTY. FUEL IMBALANCE WAS GREATER THAN 3,000LBS. CREW RAN QRH & SHUTDOWN ENGINE. UPON A/C REACHING THE GATE INSPECTED A/C FOR OBVIOUS SIGNS OF A FUEL LEAK IN REFERENCE TO AMM 28-11-00. FOUND NO OBVIOUS SIGNS OF A FUEL LEAK COMING FROM THE RH ENGINE RH WING OR WHEEL WELL AREAS. CHECK FUEL QUANTITY AT THE REFUEL/DEFUEL PANEL. LH WING HAD 6260 AND THE RH WING 3910 CENTER READ ZERO. CHECK THE FUEL QUANTITY ON EICAS FOUND TO BE CONSISTENT WITH THE FUEL PANEL. TRANSFERRED LH WING TO THE RH WING TO ABOUT EVEN. PERFORMED FQIS BITE TEST IN REFERENCE TO FIM 28-41 TASK 801. FOUND NO FAULTS STORED OR CURRENT FAULTS. PERFORMED BOTH #1 AND #2 ENGINE RUNS IN REFERENCE TO AMM 72-00-00 FOR 5 MINUTES. FOUND NO ABNORMAL FUEL FLUCTUATIONS AND NO LEAKS NOTED AFTER SHUT DOWN. PERFORMED FUEL MEASURING STICK READINGS WHEN TANKS WERE ABOUT EVEN GOT STICK 4 ON THE RH TO READ ABOUT 5.4 WITHIN LIMITS. TRANSFERRED FUEL BACK TO ORIGINAL NUMBERS AT ARRIVAL TO THE GATE AND GOT STICK 3 TO READ 11.2 WHICH IS ALSO WITHIN LIMITS OF SP#28 OF MEL 28-6-01.REMOVED AND REPLACED RT WING TANK COMPENSATOR AND TANK UNITS , F2, F3, AND F5 PER AMM 28-41-21 SEE ATTACHED AEROTEAMS W/O 66-26167.

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