An Engine Oil Goes the Distance
Inspection reveals that Mobil Delvac 1 ESP 5W-40 provides longstanding protection for Cummins marine main engine; after almost a decade of continuous use, minimal component wear and outstanding cleanliness were discovered
An inspection of one of two main engines on a U.S. inland waterways vessel revealed that ExxonMobil’s Mobil Delvac 1 ESP 5W-40 diesel engine oil provided outstanding protection and cleanliness for a Cummins KTA38 marine diesel main engine after nine years of continuous use.
The engine had accumulated 21,782 running hours with an initial fill of Mobil Delvac 1 ESP 5W-40 engine oil. Mobil SignumSM oil analysis was used to closely monitor the health of the engine throughout this period, with support from the ExxonMobil field engineering team.
ExxonMobil engineers evaluated the cleanliness of the Cummins KTA38 engine using the Coordinating Research Council (CRC) method as per Deposit Rating Manual 20. This rates component sludge contamination on a scale from one to 10, with 10 indicating a complete absence of deposit build-up.
After nearly a decade of use, Mobil Delvac 1 ESP 5W-40 synthetic diesel engine oil delivered exceptional results across a range of testing categories, including:
- Engine component cleanliness rating: 9.80
- Sump rating: 9.66
- Front of the engine block rating: 9.80
- Valve covers rating: 9.95
There was also a significant lack of wear on common wear components, such as piston skirts, piston wrist pins, cylinder liners, crankshaft and gears. All parts showed minimal signs of distress.
Oil drains were extended to a 3,000 hour interval – over 10 times longer than the engine builder’s recommendation – while maintaining Cummins’ recommended filter intervals. This can help lessen total operating costs by minimizing total lubricant consumption, thereby reducing used oil and environmental impact. Additionally, oil drain extension can help to promote productivity and safety by cutting down on human-machine interactions (HMI) and equipment downtime.
“After nine years of operation, one would expect to see deposits, scuffing and component wear,” said JR Hand, US marine chief engineer at ExxonMobil. “However, during this routine maintenance engine service overhaul, engine cleanliness levels were extremely high and wear levels were low. In fact, the marine engine could have continued to operate efficiently for longer. The results demonstrate that Mobil Delvac 1 ESP 5W-40 synthetic diesel engine oil can help enhance the performance and protection of today’s high speed marine engines.”
