Question 378General Subjects - 1st Asst/Chief70% to pass
With a machinery lubricating oil analysis program, it is important to monitor trends over time. What would be indicated by elevated copper levels associated with a recent sample of used diesel engine crankcase lubricating oil?
AI Explanation
The correct answer is C) Wear of various lead-bronze alloy bearings.
Elevated copper levels in used diesel engine crankcase lubricating oil indicate wear of lead-bronze alloy bearings. Lead-bronze alloy bearings are commonly used in diesel engine crankshafts and connecting rods. As these bearings wear, they release copper particles into the lubricating oil, leading to elevated copper concentrations detected during oil analysis.
The other options are incorrect because:
A) Aluminum-alloy bearings would not be a source of elevated copper.
B) Piston ring wear would not typically result in elevated copper.
D) White metal alloy bearings, which are tin-based, would not be a source of copper contamination.
Related Questions
#376 In accordance with the international MARPOL Annex VI regulations, the nitrous oxide (NOx) emissions associated with certain diesel engines are required to operate under certain acceptable limits. To which of the listed engine applications would the NOx emission regulations apply? #377 Which of the following fire extinguishing agents which may be found aboard ship is designated as an ozone-depleting substance as defined in the Montreal Protocol on Substances that Deplete the Ozone Layer and is controlled as a result? #379 With a machinery lubricating oil analysis program, it is important to monitor trends over time. What would be indicated by a sudden increase in metallic content of a recent sample of used diesel engine crankcase lubricating oil? #380 Elevated metal levels present in a recent sample of used diesel engine crankcase lubricating oil is indicative of a condition. What would high iron levels indicate? #381 On a vessel classed for a periodically unmanned engine room, which of the below listed events will trigger the annunciation of the engineer's assistance needed alarm?