Where is the main fuel strainer located in the aircraft fuel system? :: At the lowest point in the fuel system.
If carburetor heat is applied on an aircraft with a fuel injection system, what happens? :: Carburetor heat is not installed.
During idle mixture adjustments, what indicates the correct mixture has been achieved? :: Slight rise in RPM.
What can cause an engine with a float-type carburetor to run rich at full throttle? :: Fuel level in the float bowl set too high.
What happens if the idling jet becomes clogged in a float-type carburetor? :: The engine will not idle.
What fuel/air mixture ratio normally produces maximum power in a reciprocating engine? :: 12:1.
What results from excessively rich or lean idle mixtures? :: Incomplete combustion.
What is the primary function of boost pumps in a fuel system? :: Provide a positive flow of fuel to the engine pump.
What is the purpose of an engine-driven fuel pump bypass valve? :: Prevent a damaged or inoperative pump from blocking fuel flow from another pump.
Where must a fuel strainer or filter be located? :: Between the tank outlet and the fuel metering device.
Which is NOT a function of the carburetor venturi? :: Regulates the idle system.
What corrective action should be taken if a carburetor leaks fuel from the discharge nozzle? :: Replace the needle valve and seat.
How is the float level commonly adjusted in a float-type carburetor? :: Bend tab or add/remove shims under the needle valve.
When should engine idle speed and mixture settings be adjusted? :: With the engine warmed up and operating.
What is the function of the economizer system in a float-type carburetor? :: Supplies additional fuel above cruising power.
When are fuel boost pumps operated? :: To provide a positive flow of fuel to the engine.
On a carburetor without automatic mixture control, what happens to the mixture as altitude increases? :: It becomes richer.
Where is the engine fuel shutoff valve usually located? :: Aft of the firewall.
What is true regarding proper throttle rigging? :: The throttle stop on the carburetor must contact before the cockpit stop.
What decreases reciprocating engine power at all altitudes? :: Increased humidity.
When should float carburetors normally be overhauled? :: At engine overhaul.
Why should fuel lines avoid sharp curves and steep rises/falls? :: To prevent vapor lock.
How is float level measured in a float-type carburetor? :: From the fuel level to the parting surface of the carburetor.
Why are fuel lines kept away from heat and sharp bends? :: To reduce vapor lock.
At idle speed, where is fuel discharged in a float-type carburetor? :: From the idle discharge nozzle.
What carburetor component limits maximum airflow at full throttle? :: Venturi.
When an electric primer is used, fuel pressure is supplied by what? :: Boost pump.
Why does an aircraft carburetor have a mixture control? :: To prevent the mixture from becoming too rich at high altitudes.
What must all aircraft fuel systems include? :: A positive means of shutting off fuel to all engines.
What additional effect does a carburetor air scoop provide? :: Increases incoming air pressure by ram effect.
What happens when carburetor heat is applied? :: The mixture becomes richer.
What does an increase in RPM or manifold pressure after applying carburetor heat indicate? :: Carburetor ice was forming.
If an engine runs rough at high power and smooths out when leaned, what is the probable cause? :: Excessively rich mixture.
What is the function of the venturi in a carburetor? :: Creates a vacuum to draw fuel into the airstream.
What can result from an excessively rich fuel mixture? :: Carbon buildup on spark plugs.
What is the primary purpose of the mixture control lever? :: Adjust fuel flow for changes in altitude.
What typically happens to engine performance when carburetor heat is applied? :: Engine RPM decreases.
What device prevents or eliminates carburetor icing? :: Carburetor heat.
What condition is most likely to cause carburetor icing? :: High humidity and moderate temperatures.
What is the main disadvantage of a float-type carburetor compared to fuel injection? :: Increased risk of carburetor icing.
What is the most common fuel metering device used in small aircraft engines? :: Float-type carburetor.
What is the primary function of a carburetor? :: Mix fuel and air in the correct ratio for combustion.
What is the primary function of an aircraft induction system? :: Deliver air to the engine for combustion.
What are light aircraft engines usually equipped with? :: Carburetor or fuel injection system.
What does a typical induction system on a naturally aspirated engine consist of? :: All of these.
What does a turbocharger use to increase manifold pressure? :: Exhaust gases.
How does altitude affect a normally aspirated engine? :: Decreases power output.
What is a disadvantage of a carbureted induction system? :: Higher risk of icing.
How does an alternate air system function? :: Allows the engine to draw unfiltered air if the main filter is blocked.
What is a common method for checking induction leaks on a carbureted engine? :: Look for blue stains near the induction manifold and use a soapy water solution.
On small aircraft engines, how may fuel vaporization be increased? :: By circulating the fuel-air mixture through passages in the oil sump.
What additional effect can a carburetor airscoop provide? :: Increase the pressure of incoming air by ram effect.
What is true regarding volumetric efficiency? :: Supercharging can increase volumetric efficiency above 100%.
What fluid is commonly used for reciprocating engine induction system deicing? :: Alcohol.
What is the system called when the fuel-air mixture flows through passages in the oil sump? :: Hot Spot Induction.
What is the most satisfactory extinguishing agent for a tailpipe or intake fire? :: Carbon dioxide.
What effect does applying carburetor heat have during engine operation? :: Decreases the weight of the fuel-air charge.
If carburetor heat is applied and no icing is present, what happens? :: The mixture becomes richer.
What happens in some aircraft if the induction air filter becomes blocked? :: The system automatically allows warm, unfiltered air into the engine.
What should an operator do if an induction fire starts during engine starting? :: Continue cranking the engine.
What effect does carburetor heat have on the mixture? :: The mixture becomes richer.
What does an increase in RPM or manifold pressure after applying carburetor heat indicate? :: Ice was forming in the carburetor.
In what position should the carburetor heat control be during engine starting? :: Cold or Off.
Is carburetor heated air filtered? :: No.
What can result from using carburetor heat when it is not needed? :: Decrease in power and possible detonation.
What part of an aircraft will usually accumulate ice first in flight? :: Carburetor.
How may carburetor icing be eliminated? :: Alcohol spray and heated induction air.
What is the most common method of preventing carburetor icing? :: Preheating the intake air.
Where would the carburetor air heat valve be located in a fuel injection system? :: None is required.
What are the two most common types of aircraft induction air filters? :: Dry paper filters and wetted mesh filters
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