CRANKSHAFT FAILURE OF AUXILIARY ENGINE :


C P Mohanraj 2/E

Ship : M V Pearl of Dammam

On one of the voyages, one of the auxiliary engine’s unit 2 bottom end bearing wiped out.
The ship had only two auxiliary engines. This failed unit’s crank pin was already undersized. No spare on board. The standby generator (the other one) was run and after a few days that also started giving problem. Major work had to be carried out, hence it was decided that the broken down generator has to be run atleast on part load.

Manufacturer’s were consulted and as per their instructions, unit 2 was isolated physically by disconnecting the connecting rod and piston, cylinder blanked off and the engine was started, tried out on no load for 5’, 10’ etc. The ship was asked to try out the generator on part load, and when 20 kw load was given, big noise came from the crankcase and engine stopped.

Found the adjacent unit’s crank web broken into two pieces.It led to the renewal of complete crankshaft.

Lesson learnt :

immediately after breakdown, a thorough inspection to be carried out and all the defects to be noted and rectified.