Incident :

Generator Engine broke down and one of the unit piston came out with connecting rod and damaged whole engine block and crank shaft damaged.

Cause :

Found particular unit bottom end bearing bolts sheared off. The lubricating oil pressure was found satisfactory while running. Thorough inspection was carried out in the presence of surveyor. The healthy unit bottom end bearing was checked, and found the bottom end bolts were not fully tight and this unit also could have failed. On opening the bottom end bearing, it was found that the serrations were not cleaned thoroughly as per the manufacturer’s instructions and senior engineers did not check the cleaning part before boxing back. Hence the effective tightening could not be achieved and resulted in a major damage. The engine blocks, crankshaft and all bearings replaced.

Lesson Learnt :

2nd engineer or chief engineer should take the responsibility of checking the cleanliness of parts before boxing back. Also the inference from the above incident is that while trying out at low speed and on no load, after stopping the engine, the tightness were not checked. It should be checked religiously before taking it on full load.
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