in one of the ships Aux Engine Man B&W 8328 LH/2 series when started went to over speed and was tripped by over speed device. The engine was tried out two three times and all the time it went to over speed and tripped at over speed. First all the fuel and related systems checked all found OK. Later it was suspected may be the pneumatic spool valve in over speed device might have gone wrong and thus actuating the stop cylinder but it was also wrong as there was no problem in to the pneumatic device.

Later it was thought, may be the Governor might have went wrong thus a governor from other running generator was tried out with this engine and still this AE went over speed on starting and tripped. All connections checked and found ok. All Crankcase doors opened and sump cleaned and checked for any abnormally but all found ok. Later when engine was continuously turned manually, a minute abnormal noise was heard around the gear case. Hence the gear case was completely removed on the rear side and was found of the drive gear to the governor was damaged and hence governor could not sense the speed of AE.
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