If an engine oil tank must be replenished, how many minutes must elapse after shutdown before servicing the engine?

If an engine oil tank must be replenished, how many minutes must elapse after shutdown before servicing the engine?

• A. 5 minutes
• B. 10 minutes
• C. 15 minutes
• D. 20 minutes

Answer: (C)

The main idea is to allow the oil system to settle and cool before adding oil. After shutdown, oil in the engine and lines is still warm and some of it remains distributed through the pump and fittings. Waiting about 15 minutes lets the oil drain back into the tank and the system pressure drop to ambient, so you can read the true oil level and handle components safely. Servicing too soon can give an inaccurate reading and risks burns from hot oil or surfaces. After the 15-minute wait, topping up the oil gives a correct, safe replenishment.

The main idea is to allow the oil system to settle and cool before adding oil. After shutdown, oil in the engine and lines is still warm and some of it remains distributed through the pump and fittings. Waiting about 15 minutes lets the oil drain back into the tank and the system pressure drop to ambient, so you can read the true oil level and handle components safely. Servicing too soon can give an inaccurate reading and risks burns from hot oil or surfaces. After the 15-minute wait, topping up the oil gives a correct, safe replenishment.