Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Troubleshooting
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Other / Unknown
Flight Crew Returned To Gate; General Flight Cancelled / Delayed; General Maintenance Action
Aircraft
Operating Aircraft X ZZZ to ZZZ1 as Captain on Date. Departed Gate XX using #2 engine but aware of 5 minute warm-up for engine #1. With approximately 8 aircraft in front of us for T/O; I called for the 'Delayed Engine Start' procedure. Engine #2 starts normally and is running for at least 6-7 minutes before Tower tells us to 'Line up and wait Runway XXR/W'. During taxiing onto Runway XXR; another Company aircraft tells us that they have observed flames coming out of the tail cone of #1 engine. We ask and receive permission to taxi off Runway and ask for ARFF (airport rescue and firefighting) to come out and have a look. I make ELB write-up. During the entire time; there were no abnormal engine indications in the cockpit. Both engines shut-down; Fire Chief reports small fuel leak from engine #1. Maintenance asks us to proceed to [area] for further inspection. Maintenance says; 'There is oil leaking where it should not be'. Maintenance advises that write-up for oil leak will be accomplished by Maintenance. Maintenance advises aircraft will be towed to gate XY for further investigation. Over an hour spent at Gate XY until ops advises swap with new airplane at Gate XZ. Flight leaves 4 hours late and proceeds uneventfully to ZZZ1.
Upon being cleared onto runway another aircraft informed us of flames briefly coming from engine number 1. We coordinated with ATC; fire department; Company Maintenance; Dispatch; and Operations as well as crew and customers. Fire department said they observed a fuel leak after number 1 was shutdown but no other issues. At a hard stand Company maintenance stated they saw oil in the number 1 engine. We were tugged to a gate where we deplaned and given a new aircraft at a different gate.
B737 flight crew reported that another Company flight crew informed them of a tail pipe fire on their #1 engine during taxi for take off. Flight crew secured the engine and maintenance diagnosed the issue; which resulted in the aircraft removed from service.