AMT Engine Fuel Metering Systems 2

Question 1

What is the primary function of an accelerator pump in a float-type carburetor?

Accepted Answer

Provide extra fuel during rapid throttle opening to prevent a lean mixture

Answer

Increase idle fuel flow during warm-up

Answer

Reduce fuel pressure during high-power settings

Answer

Meter fuel during cruise flight conditions

Question 2

In a pressure-injected carburetor, the fuel control unit meters fuel based primarily on which parameter?

Accepted Answer

The differential pressure between impact air and venturi suction

Answer

Throttle position only

Answer

Manifold absolute pressure

Answer

Engine RPM as sensed by a governor

Question 3

Which component in a continuous-flow fuel injection system controls fuel distribution to individual cylinders?

Accepted Answer

Flow divider (fuel manifold valve)

Answer

Fuel control unit

Answer

Engine-driven fuel pump

Answer

Mixture control arm

Question 4

What is the purpose of the idle cut-off position on a mixture control?

Accepted Answer

Stop fuel flow to shut down the engine cleanly

Answer

Enrich the mixture for starting

Answer

Activate the primer system

Answer

Switch from main tanks to auxiliary tanks

Question 5

A carburetor's economizer system (power enrichment valve) is designed to:

Accepted Answer

Enrich the mixture at high power settings to prevent detonation and overheating

Answer

Lean the mixture at cruise power to improve fuel economy

Answer

Provide additional fuel during engine starting

Answer

Compensate for altitude changes automatically

Question 6

In an RSA fuel injection system, the fuel control unit is driven by:

Accepted Answer

Airflow through the throttle body, sensed by an air diaphragm

Answer

An electric motor independent of the engine

Answer

Engine oil pressure

Answer

A mechanical connection to the magneto

Question 7

When troubleshooting a float-type carburetor that floods excessively, the FIRST item to inspect is:

Accepted Answer

Float level and needle valve for wear or contamination

Answer

Accelerator pump check valve

Answer

Main discharge nozzle for blockage

Answer

Idle mixture adjustment screw