Oilers/Plant Tenders (HHC) Civil Service Practice Exam

For which purpose is the hand-operated choke primarily designed?

1. To increase fuel flow

2. To regulate temperature

3. To ensure consistent power

4. To provide excess air

The correct answer is: To provide excess air

The hand-operated choke is primarily designed to provide excess air, which is essential for the proper functioning of an internal combustion engine during cold starts. When the engine is cold, it needs a richer fuel-air mixture to maintain ignition and smooth operation. The choke restricts the air intake, creating a higher concentration of fuel in the mixture, helping to ensure that the engine runs effectively until it reaches its optimal operating temperature. While the other options relate to engine performance, they do not accurately describe the function of the choke. For instance, increasing fuel flow is typically managed by fuel injectors or carburetors rather than a choke. Similarly, regulating temperature is more closely associated with the thermostat or coolant system of an engine, and ensuring consistent power relies on various systems working together rather than solely on the choke's function. The choke's main role centers around adjusting the air-fuel ratio for smooth engine performance, especially in cold conditions.