🔍 Key Concepts

• viscosity of lube oil and how it changes with temperature • role of the lube oil cooler and seawater in controlling oil temperature • purpose of zinc anodes in coolers

💭 Think About

• Think about what happens to oil pressure in a pump when the oil becomes thinner versus thicker. Which direction does the pressure usually move? • Which of these options would most directly change the oil’s viscosity in a way that could reduce discharge pressure from a positive‑displacement lube oil pump? • Ask yourself whether zinc anodes in a cooler affect flow/pressure, or primarily protect against something else.

✅ Before You Answer

• Verify how increasing lube oil temperature affects oil viscosity and pump discharge pressure. • Consider whether lower seawater temperature would tend to cool the lube oil more (making it thicker) or less (making it thinner). • Confirm the main function of lube oil cooler zincs (corrosion protection vs. flow/pressure control).