B737 Undifferentiated or Other Model
Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Flight Crew Last 90 Days 166; Flight Crew Total 1039; Flight Crew Type 1039
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Weight And Balance; Inflight Event / Encounter Fuel Issue
Flight Crew Diverted; Flight Crew Landed in Emergency Condition
Aircraft
[During cruise]; crew noticed left fuel tank quantity decreasing slowly; but steadily with fuel remaining in the center tank.Monitoring during cruise with reference to the Operational Flight Plan did not indicate a fuel leak. However; the situation would eventually cause an imbalance. Additionally; the wing tanks are meant to be full with greater than 1;000 pounds in the center tank.Due to the abnormal situation and after consulting with the company; the decision was made to divert to ZZZ. [ATC was advised] due to the aircraft exceeding an operational limitation and proceeded directly to ZZZ.An overweight landing to Runway 1C was performed and the aircraft stopped once clear to allow for an external inspection to be performed by the Aircraft Rescue & Fire Fighting team.No defects were noted and the aircraft proceeded to the gate without incident.
Although wing fuel tanks were full at departure; the left fuel tank quantity decreased 400 pounds to 8;160 lbs; with more than 1;000 (approximately 8;000) pounds in the center tank. This exceed our limitation requiring wing tanks full with more than 1;000 pounds in the center tank. We ran the suspected fuel leak checklist and determined there was no leak. With support from Dispatch; [Maintenance Control]; [Flight Ops Manager] we elected to divert to ZZZ. [ATC was advised] and we landed without further incident.
B737 flight crew reported excessive fuel consumption during cruise resulting in a diversion.