Fuel Metering: Pressure Carbs, and Fuel Injection

Question 1

A pressure-injection carburetor discharges fuel into the center, or eye, of the internal ______________.

Answer 1

Supercharger Impeller

Question 2

Two components of the air metering force are ________ pressure and _________ pressure.

Answer 2

Venturi

Impact Air

Question 3

Metered fuel is held at a constant pressure by the spring-loaded _________ valve.

Answer 3

Discharge Nozzle

Question 4

The device that automatically adjusts the fuel-air mixture ratio to keep it constant as the altitude changes is the __________.

Answer 4

Automatic Mixture Control

Question 5

Fuel vapors that collect in a pressure carburetor are returned with a small flow of fuel to one of the aircraft ________.

Answer 5

Fuel Tanks

Question 6

Idling fuel pressure is produced by a _________ in chamber A which holds the poppet valve open when there is only a small amount of air flowing through the carburetor.

Answer 6

Spring

Question 7

The acceleration pump diaphragm is held against spring pressure by _________ manifold pressure.

Answer 7

Low

Question 8

The manual mixture control in a pressure carburetor is an adjustable __________ between chambers A and B.

Answer 8

Needle Valve

Question 9

The automatic mixture control _______ the fuel-air mixture as the aircraft goes up in altitude.

Answer 9

Leans

Question 10

The power-enrichment system adds additional fuel when the engine is operating at __________ power.

Answer 10

High

Question 11

The amount the idle fuel valve remains off its seat can be adjusted to change the idle __________.

Answer 11

Mixture

Question 12

When the throttle is suddenly opened, the fuel from the acceleration pump is forced out into the air stream by __________.

Answer 12

A Spring

Question 13

The automatic mixture control is ________ with the manual mixture control.

Answer 13

Parallel

Question 14

The power enrichment valve on a PS carburetor is ________ to the main metering jet.

Answer 14

Parallel

Question 15

Overhaul of a pressure carburetor is a _______ repair.

Answer 15

Major

Question 16

Before returning an engine to service after the installation of a freshly overhauled pressure carburetor and the carburetor allowed to sit with fuel in it for at least ____ hours.

Answer 16

8

Question 17

An engine equipped with a pressure carburetor is started with the mixture control in the __________ position

Answer 17

Idle Cutoff

Question 18

When adjusting the idle mixture control, pull mixture control toward IDLE CUTOFF and watch the tachometer. Before the engine dies the RPM should momentarily__________.

Answer 18

Increase

Question 19

The four subsystems for an RSA fuel injection system are:
\_\_\_\_\_\_\_\_
\_\_\_\_\_\_\_\_
\_\_\_\_\_\_\_\_
\_\_\_\_\_\_\_\_

Answer 19

Servo Regulator
Fuel Control
Flow Divider
Nozzles

Question 20

The mixture control oraface and main metering jet of an RSA fuel injection system are in ________.

Answer 20

Series

Question 21

The air metering force in an RSA fuel injection system tends to ________ the servo valve.

Answer 21

Open

Question 22

Unmetered fuel pressure acting on one side of the fuel diaphragm tends to ________ the servo valve.

Answer 22

Close

Question 23

When airflow in the engine increases, the pressure drop across the main metering jet _________.

Answer 23

Increases

Question 24

The servo valve in the RSA fuel injection system __________ meter fuel.

Answer 24

Does Not

Question 25

The RSA fuel injection system __________ have a seperate idle metering jet

Answer 25

Does Not

Question 26

The servo ball valve is held off its seat during idle conditions by the constant-_______ spring

Answer 26

Head

Question 27

The movement of the air diaphragm is assisted when transporting fuel from idle to cruise power by the constant-_________ spring.

Answer 27

Effort

Question 28

The automatic mixture control ________ the pressure difference across the air diaphragm when the aircraft goes up in altitude.

Answer 28

Decreases

Question 29

The power-enrichment jet is in ________ with the main metering jet.

Answer 29

Parallel

Question 30

Three functions of the flow divider are: __________ __________ __________

Answer 30

Aids in constant idling Distributes fuel evenly to all cylinders Provides a positive shut off when the engine s shut down

Question 31

An engine equipped with an RSA fuel injection system is started with the mixture control in the ________ position

Answer 31

Idle Cutoff

Question 32

Fuel for starting the engine is sprayed into the intake valve chamber by momentarily moving the mixture control to the __________ position with the boost pump turned on.

Answer 32

Full Rich

Question 33

Increasing the length of the rod connecting the throttle air valve with the throttle fuel valve causes idle mixture to become ________.

Answer 33

Richer

Question 34

A plugged injector nozzle will indicate on the flowmeter as a/an ________ flow.

Answer 34

Increased

Question 35

``` The four basic components of the TCM fuel injection system are: ________ ________ ________ ________ ```

Answer 35

Engine driven injector pump Fuel air control unit Fuel manifold valve Nozzles

Question 36

The devices in a TCM fuel injection system that varies pressure of fuel going to the metering jet is the ________.

Answer 36

Injector Pump

Question 37

Vapors are separated from fuel in a TCM fuel injection system in the __________.

Answer 37

Injector Pump

Question 38

Fuel from the auxiliary pump for starting the engine flows around the injector pump vanes through the __________.

Answer 38

Bypass Valve

Question 39

The low unmetered fuel pressure is set by adjusting the________ in the injector pump

Answer 39

Relief Valve

Question 40

The high unmetered fuel pressure is set by adjusting the ________ in an injector pump

Answer 40

Orifice

Question 41

The TCM fuel-air control unit __________ use a venturi to sense the amount of air flowing into the engine.

Answer 41

Does not

Question 42

The adjustable stop that controls the amount the throttle air valve remains open when the throttle is all the way back determines the idle ______.

Answer 42

RPM

Question 43

The bellows in the injection pump on a turbo charged engine controls the ________.

Answer 43

Orifice

Question 44

The opening of the orifice in series with the relief valve in a TCM fuel pump used on a turbo charged engine is controlled by a bellows that senses the _________ or __________ pressure.

Answer 44

Upper deck | Turbocharger discharge

Question 45

A stable fuel pressure downstream of the metering jets under idling conditions is provided by the ________ valve in the fuel manifold

Answer 45

Poppet

Question 46

When checking the low unmetered fuel pressure, the engine is operated at its ________ RPM.

Answer 46

Idle