Date: 202112
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Light: Night
Aircraft: B737 Next Generation Undifferentiated
Operator: Air Carrier
Operating under: Part 121
Mission: Passenger
Flight phase: Climb
ATC / advisory: TRACON ZZZ
Aircraft component: Turbine Engine
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Result: Flight Crew Returned To Departure Airport
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: Shortly after takeoff from [Runway] XXR/W at ZZZ we had a Master Caution light illuminate with OVHT/DET annunciated. I was flying; it was at night; and this occurred around 1;500 feet during the most inappropriate time of this busy departure. It is a 'yellow warning light' after all; my intention was to fly the airplane first; get it stabilized; engage the autopilot; then assess the situation. I was busy hand flying headings with the anticipation of leveling off at 2;500 feet; we did get cleared to 6;000 feet without having to level off at 2;500 feet. My FO (First Officer) was busy with ATC instructions; retracting flaps; after takeoff checklist; MCP and FMC programming per ATC instructions; in addition to having a caution light illuminated in his face. From his field of view; it is difficult to see 'Eng 1 Overheat' with the number 1 Fire Handle in the way. Once the airplane was stabilized with the autopilot engaged and climbing out of 3;000 feet to 6;000 feet; we now devoted our attention to the issue and confirmed the emergency. My FO advised me that this is an immediate action item; we leveled off at 6;000 feet and the engine thrust began to reduce. Taking a deep breath and processing the immediate action item; the Eng 1 Overheat light extinguished before the immediate action was performed. Moments later; ATC clears us to 17;000 feet. We complied and started climbing; shortly after climb power was applied the Eng 1 Overheat light illuminated again. Fully aware of the severity of the situation now; the immediate action item was performed. The auto throttles were disconnected and the number 1 engine lever reduced to idle; the Eng 1 Overheat light extinguished. We leveled off at 9;000 feet; informed ATC of our desire to maintain 9;000 feet; advised ATC; and requested vectors back to ZZZ. We then followed up the immediate action items with the QRH. As a result; we were left with the number 1 engine at idle. I notified the FAs (Flight Attendants) of our return; 10 minutes to landing; engine indication warrants our return; no need to prep; no special instructions. I informed the passengers that an engine indication warrants our return to ZZZ; we should land in about 10 minutes; please follow your FAs instructions. We decide to fly an ILS approach using single engine procedures with the number 1 engine at idle. We ran the 'one engine inoperative landing' QRH procedure and asked ATC for vectors to an ILS [Runway] XXR approach with a turn to final about 3 miles outside of the FAF. It was VFR; but I felt better trained flying a single engine approach with the ILS since we were not on fire and could always revert to a visual if the situation deteriorated. We landed several thousand pounds overweight but we felt the severity of the engine overheat outweighed the need to loiter to burn fuel down to below maximum landing weight. Everything else was uneventful. Got to the gate where the passengers deplaned with very little delay. Completed two ELB reports; overweight landing; and Eng 1 Overheat. I was met and debriefed by a mechanic and the Flight Ops Rep and I debriefed over the phone.


Second narrative: This report describes the 'engine overheat' light which came on after takeoff during flight (ZZZ-ZZZ1)The preflight; taxi; and initial takeoff roll were all normal and uneventful.After takeoff; the number 1 engine overheat light came on during the climb; at around 1;200 feet; along with a master caution. There were no other engine indication malfunction that we could notice.As we didn't want to address the malfunction close to the ground; we continued the takeoff; retracted flaps on schedule and finished the after take-off checklist.On initial contact with Departure Control; ATC told us to go direct ZZZZZ and climb to 6;000 feet. We were about to run our memory items and run the appropriate ENG 1 OVERHEAT checklist; but when we leveled off at 6;000 feet; the thrust was reduced and the warning indication disappeared. Nevertheless; we started running the QRH procedure.ATC cleared us to climb to 17;000 feet and as we increased the thrust for the climb; the engine overheat light reappeared. We had already considered an air return back to ZZZ; so at that point; the Captain's decision to return to Newark was finalized. We then asked ATC to level off at 9;000 feet and requested vectors back to land on the longest runway in Newark: [Runway] XXR. We also advised ATC for priority handling. The Captain notified the cabin crew; made a brief PA to the passengers while I was sending an ACARS message to Dispatch to notify them of our air return. We continued the QRH Procedure and ran the ONE ENGINE INOPERATIVE LANDING checklist; since the left engine was now at idle; as per the QRH.ATC initially offered a visual approach for runway [Runway] XXR; but we requested the ILS. We landed uneventfully on runway [Runway] XXR. Emergency vehicles were waiting for us upon landing and followed us to Gate XX as a precaution; but no other assistance was needed.We had to wait a few minutes short of the gate for the Ground Personnel to arrive; so we made the appropriate PA to keep everyone seated. We parked the plane; waited again for a Gate Agent and the passengers were deplaned.A Maintenance Technician got on board and we described the event to him and we wrote up the maintenance issue. The Captain got a call from Flight Ops and updated him on the situation.A replacement airplane was available; but after a brief discussion with Flight Ops; it was agreed that we would not be fit to continue the flight to ZZZ1 since our mind was still preoccupied by the recent events.After a short wait; we were sent to the [hotel] for the night and assigned a new dead head flight home the next day which was the last day of our 4 day pairing.


Synopsis: B737 flight crew reported an engine malfunction after takeoff resulting in a return to the departure airport.