🔍 Key Concepts

• Moisture removal vs. particle filtration – which component in a fuel system is specifically designed to separate water from fuel? • Function of coalescing filters – what does a coalescing type diesel oil filter actually do to water droplets in fuel? • Proper use of vents vs. drains – how do vent valves and drain valves each affect air, vapor, and liquid in a fuel system?

💭 Think About

• Ask yourself: Which option actually removes water that has already collected in the fuel system, rather than just trying to keep new moisture out? • Consider how a coalescing filter works: once water is collected or separated inside it, what must be done so that water does not eventually pass downstream? • Look at each choice and decide: Is this a safe, normal maintenance practice, or could it create other hazards (like tank collapse, contamination, or unnecessary component wear)?

✅ Before You Answer

• Identify which device in the choices is designed to collect and hold water until it is removed. • Verify which valve operation (vent vs. drain) will actually discharge liquid water instead of just air or vapor. • Eliminate any practice that would restrict proper venting of tanks or focuses only on filter replacement for solids, not water.