FAA Powerplant Written Practice Test

How does a floating control thermostat function in terms of oil temperature regulation?

1. It lowers oil viscosity

2. It controls airflow through the oil cooler

3. It stops oil flow

4. It increases oil flow rate

The correct answer is: It controls airflow through the oil cooler

A floating control thermostat plays a crucial role in managing the temperature of oil within an engine, particularly in the context of regulating the amount of airflow through the oil cooler. This component operates by responding to the temperature of the engine oil. When the oil reaches a certain temperature threshold, the thermostat adjusts a valve to either increase or decrease the airflow through the oil cooler, ensuring that the oil is maintained within a designated temperature range. This regulation is vital because maintaining the proper oil temperature is essential for optimal engine performance and longevity. If the oil is too cool, it could cause increased viscosity, leading to inadequate lubrication and potential engine wear. Conversely, if the oil is too hot, it could lead to a reduction in its lubricating properties and increased risk of component damage. In this scenario, controlling airflow through the oil cooler allows the floating control thermostat to effectively manage these temperature extremes, ensuring that the oil remains at a temperature that is conducive to efficient engine operation.