Date: 201411
Location: ZZZ.Airport, US
Flight conditions: VMC
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Flight phase: Taxi
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Human factors: Situational Awareness
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew; Person Ground Personnel
When detected: Aircraft In Service At Gate
Result: Flight Crew Returned To Gate; General Flight Cancelled / Delayed; General Maintenance Action
Contributing factors: Aircraft; Human Factors; Procedure
Primary problem: Aircraft

Narrative: I had to do a gate return due to a possible fuel leak on the right engine after pushback and engine start. I entered the problem in the maintenance logbook.  There was some talk by the Maintenance (Mx) supervisor about an engine run at the gate. I advised him that we were willing to help but only after conferring with Maintenance Control and complying with the FOM. He said that he didn't think that an engine start would be necessary. I said ok. He then said he needed to get in my seat to get to the fmc. I proceeded out of the flight deck and onto the jet bridge. The First Officer (F/O) remained at his seat. Another mechanic arrived and asked the F/O to leave his seat about five minutes later. He joined me on the jet bridge.  The airplane was fully loaded with passengers and all flight attendants on board. To my dismay I heard the right engine start to turn. I ran back to the flight deck but it was locked. I knocked on the door but no one answered. I ran down the jet bridge stairs and around the nose of the aircraft. There I saw the right engine turning but not at idle. No fuel was ever introduced to the engine. There were mechanics around and under the TURNING engine. I returned to the flight deck. The Mx supervisor had stopped turning the engine and the cockpit door was now open. I asked him why he was turning the engine without compliance with the FOM? He said that they could do it as long as they didn't bring the start lever out of [cutoff]. I explained that I strongly disagreed and felt that We were misled when asked to vacate our pilot seats with passengers on board. He once again said that I was wrong and he did everything right. If I would have known that he was planning on turning or worse yet starting an engine; I would have deplaned the airplane and the handed the empty airplane over to them at that time. This was in my opinion a breakdown in communication whether intentional or not. We had had a major fuel leak on the right engine after start not twenty minutes earlier. We had fumes on the airplane for a short time thereafter. If I had thought that they were planning on doing what they did; the passengers and crew would not have remained on board! The end result was that they had a major fuel leak in the right engine stator vanes. They had to deplane everyone anyway and we got a different airplane.




Synopsis: B737 Captain reports returning to the gate for a possible fuel leak. Maintenance asks for access to the cockpit to troubleshoot while the Flight Crew stands in the Jetway. The Captain hears the starter engage and the engine begin to turn and attempts to enter the cockpit but the door is locked. Fuel is never introduce to the engine but a fuel leak in the stator control is verified. The Captain believes that the mechanics have violated company policy by starting an engine with passengers and crew on board and the mechanics do not; since fuel was never introduced.