AUXILIARY ENGINE BREAKDOWN :
Vessel Crude oil tanker, 1,15,000 DWT. After berthing and finished with engines, one auxiliary engine was off loaded from control room. Within two minutes, E/R fire alarm sounded.On investigation, it was found that smoke was issuing out of the generator engine c/case relief door and through the crankcase seals. The engine was stopped immediately.After allowing for enough cooling, the crank case doors were opened up.
No sign of overheating of bearings was observed. Unit 4 liner and piston suspected to be damaged. The engine was turned manually, found easily turning. The lubricating oil pump was started and engine was kept turning manually. Oil was found coming out of the drain holes at the bottom of the connecting rod. These holes were supposed to have been plugged properly, as these holes were done to drill the passage for LO to flow through the connecting rod to gudgeon pin.The bottom end bearing was opened up and found to be in good order.
The gudgeon pin and piston rings were damaged and the liner was scored. The unit’s liner, piston and gudgeon pin were renewed from spares. The ship was under guarantee period and hence all the units were checked and found in order. This was a manufacturing fault. Even then the watch keeping should be perfect to note such failures immediately well before any major damage could take place.