The National Transportation Safety Board (NTSB) has issued an investigation report regarding a diesel generator engine failure on board Offshore Supply Vessel Ocean Guardian.
On May 27, 2022, about 1435, the offshore supply vessel Ocean Guardian was conducting sea trials in Shilshole Bay near Seattle, Washington, when its no. 3 main diesel generator engine suffered a mechanical failure that resulted in a fire in the engine room.
The crew extinguished the fire before it could spread throughout the vessel. There were no injuries reported for the 22 crewmembers and contractors on board, and there was no pollution reported. Damage to the Ocean Guardian totaled an estimated $1.1 million.
Probable cause
NTSB determined that the probable cause of the mechanical failure of the no. 3 main engine and resulting fire aboard the offshore supply vessel Ocean Guardian was the replacement of a crankshaft main bearing with an incorrectly sized bearing during an engine overhaul. This was due to the engine service technicians not identifying the removed bearing’s part number, which resulted in the loss of lube oil pressure in adjacent connecting rod bearings.
Lessons Learned
Ensuring Correct Replacement Parts
When maintenance is performed, correct replacement of machinery components is critical to ensuring safe and reliable vessel operation. Vessel crews and equipment manufacturer technicians should carefully identify and document part numbers of all components removed from shipboard equipment. Tracking systems are an effective form of recordkeeping that can be used to ensure proper replacement part selection for reinstallation.
