During preflight, the engine oil level should be between the __ and __ lines on the sight glass if checking within 15 minutes of shutdown.

• A. Bottom and Min
• B. Top and Max
• C. Min and Max
• D. Min and Mid

Answer: (C)

Reading the engine oil on the sight glass after shutdown is about confirming the oil has settled and is within the designated range. The sight glass has a Minimum and a Maximum mark, and the acceptable preflight reading is between those two lines if you check within 15 minutes of shutdown. Waiting a short period allows oil to drain back into the sump so you get an accurate indication of the actual oil in the system. Staying between the Min and Max lines ensures there’s enough oil for proper lubrication without overfilling, which can cause foaming or other issues. Reading below the minimum risks oil starvation and potential engine damage, while reading above the maximum risks overfill problems.