On a particular day, the 3/E checked up the ER for UMS requirements, found everything satisfactory, changed over the system to UMS mode and left the engine room.Around 0400 hrs next day morning, alarm sounded, and on reaching ER it was found that ‘high level bilge aft’ alarm had come. On inspection, 3/E found heavy oil in good quantity under the running Auxiliary Engine and the level was quite high. Standby engine was started and taken on load and this engine was stopped.

Found the mechanical seal of the booster pump had given off, thereby the heavy fuel oil was leaking.This leaking oil had first filled up the AE platform and then through the drain had gone to the bilges. AE was running on sea load, the booster pump pressure was sufficient to run the engine.

Lesson learnt :

even though the inspection was carried out before changing over the mode to UMS clause, it is advisable to have one more inspection during the night time.