(WASHINGTON) — A U.S. Coast Guard inspected dredging vessel suffered a loss of propulsion on the starboard main diesel engine and subsequently required a tow into port. The subsequent investigation revealed that the engine’s exhaust gas recirculation (EGR) cooler was cracked and leaking, which led to a high jacket water temperature alarm and an eventual shutdown of the starboard main engine.
Coast Guard Marine investigators traced the cause to a weld seam crack on the corner of the cooler of a Wabtec Environmental Protection Agency (EPA) Tier 4/International Maritime Organization (IMO) Tier III (MDC) marine engine. After reviewing the vessel’s service history, marine investigators discovered that on six separate occasions over the previous two years, the vessel’s Wabtec engine EGR cooler had failed due to a weld seam crack. Each failed cooler was well below its designated overhaul interval.
Through further investigation, it was determined that Wabtec Corp. was aware of this problem and later issued a service notification (dated December 2024) to alert its channel partners and dealers. The service notification was not issued directly to Wabtec’s customers and end users.
Because of the safety issues that may arise in the event of engine failure, the Coast Guard strongly recommends owners and operators of vessels using Wabtec EPA Tier 4/IMO Tier III marine engines to:
• Inspect the EGR coolers on their engines to check for signs of the failure described above.
• Conduct these inspections regularly, including prior to entering or leaving port.
• Include these regular inspections in the vessel’s safety management system, if applicable. These recommendations are in place until Wabtec is able to develop a permanent solution to rectify the issue.
If a failure is found, or if the system experiences unusual or repeated high-temperature or low-pressure alarms, the Wabtec channel partner or the dealership where the system was purchased can be contacted for further guidance.
Through its channel partners and dealerships, Wabtec provided the following guidance to customers and end users:
• Make sure the cooling system water circuit pressures are set up correctly for the vessel’s expansion tank height.
• Ensure off-engine piping is designed to avoid air pockets that could later enter the water side of the EGR cooler operation. These pockets can cause localized overheating that won’t show up in water pressure readings.
• Always bleed air from the system after any work that requires draining coolant from the engine.
• Use proper cooling water treatment and corrosion inhibitors. Poor water quality can cause mineral buildup on heat transfer surfaces, reducing cooling efficiency.
• Watch for sudden drops or slow changes in EGR cooler water inlet pressure or engine water inlet pressure. Unusual pressure changes could indicate a leak allowing exhaust manifold pressure to enter the water side of the EGR cooler.
This safety alert is provided for informational purposes only and does not relieve any domestic or international safety, operational, or material requirement. This safety alert was developed by Sector Mobile and distributed by the Office of Investigations and Casualty Analysis. Questions may be sent to HQS-SMB-CG-INV@uscg.mil.
– U.S. Coast Guard
