FAA Powerplant Written Practice Test

How much expansion space must an oil tank with a capacity of 5 gallons have?

1. 1 quart

2. 2 quarts

3. 3 quarts

4. 4 quarts

The correct answer is: 2 quarts

The amount of expansion space needed for an oil tank is determined by the potential for expansion due to temperature changes. For a 5-gallon oil tank, it is essential to have a designated expansion space to accommodate the increase in volume as the oil temperature rises. Generally, the recommended expansion space is 10% of the tank's capacity. When calculating 10% of 5 gallons, you arrive at 0.5 gallons, which is equivalent to 2 quarts. This amount ensures that as the oil heats up, there is sufficient space to prevent overflow, maintain safe operating conditions, and protect the tank from excessive pressure. Therefore, having 2 quarts of expansion space is essential for effective operation and is in line with industry standards for oil tanks of this capacity.