Lube Oil (LO) reduces wear and dissipates heat generated throughout the —

• A. Propulsion process
• B. Electrical system
• C. Fuel system
• D. HVAC system

Answer: (A)

Lube oil’s job is to minimize metal-to-metal wear and carry away heat from moving parts. In a ship, that means the propulsion machinery—the main engine, reduction gears, and shaft bearings—where the oil forms a protective film, reduces friction, and dissipates heat generated by turning the propeller. It isn’t the primary lubricant or coolant for electrical, fuel, or HVAC systems, which have different lubrication or cooling needs. Therefore, lube oil reduces wear and dissipates heat throughout the propulsion process.