B3U1 Engine Systems

Question 1

What is the purpose of the engine block?

Answer 1

It houses all of the internal components of the engine.

Question 2

What are the main journals?

Answer 2

The round surfaces on which the crankshaft rotates.

Question 3

What two categories do rings fall?

Answer 3

(1) Compression.

(2) Oil.

Question 4

Why does the cylinder head contain elaborate coolant passages?

Answer 4

To help remove heat from the combustion chamber.

Question 5

Describe the movement in an engine’s stroke.

Answer 5

It can be in either direction, up or down.

Question 6

What are the events for an engine?

Answer 6

Intake, compression, ignition, power, and exhaust.

Question 7

To what does compression ratio refer?

Answer 7

The comparison in the volume of the combustion with the piston at BDC to the volume of the combustion chamber with the piston at TDC.

Question 8

What does a two stroke engine use to pressurize the air in the air box?

Answer 8

External Blower

Question 9

To what temperatures does compression causes the air in the combustion chamber to increase?

Answer 9

Above 1000 Degrees F

Question 10

When is fuel injected into the cylinder?

Answer 10

Just before TDC

Question 11

Why do four stroke engines not require an external blower?

Answer 11

A four stroke generated vacuum with the downward movement of the piston.

Question 12

What components make up the battery ignition system?

Answer 12

(1) Battery.
(2) Ignition switch.
(3) Ignition coil.
(4) Breaker points.
(5) Condenser.
(6) Distributor.
(7) High-tension wire.
(8) Spark plug.

Question 13

What does the secondary coil having more coils than the primary coil cause?

Answer 13

The secondary coil to build up much more voltage, up to about 25,000 volts, than the primary coil.

Question 14

What does the fuel filters do?

Answer 14

Removes dirt and foreign particles from the gasoline.

Question 15

What is the venturi?

Answer 15

The venturi is a restriction in the air passage.

Question 16

What does the throttle valve do?

Answer 16

Regulates the amount of air/fuel mixture entering the cylinders by restricting the passage

Question 17

Of what materials are gaskets made?

Answer 17

(1) Fiber cork.
(2) Synthetic rubber.
(3) Copper.
(4) Other soft metals.

Question 18

What conditions are inspected on vibration dampeners?

Answer 18

Chips and cracks

Question 19

What are signs of a combustion chamber leak when inspecting cylinder heads?

Answer 19

Discoloration and or rust around the combustion chamber Burned or warped valves, worn piston rings, and cylinder liners are some of the defects that cause a loss of compression.

Question 20

What do improper adjustments to a carburetor cause?

Answer 20

(1) Engine backfires through carburetor
(2) Engine overheats
(3) Engine surges
(4) Engine misses
(5) Engine stops
(6) Engine turns over but fails to start

Question 21

What are the causes of a gasoline engine to crank but not start?

Answer 21

(1) Engine flooded.
(2) Battery low.
(3) Empty fuel tank.
(4) Faulty fuel pump.
(5) Water, dirt or gum in gasoline.
(6) Faulty carburetor.
(7) Spark plug(s) fouled or wet.
(8) Spark plug(s) gap incorrect.
(9) Ignition cable disconnected or broken.
(10) Overheating shutdown switch faulty.
(11) Ignition cable wet or oil soaked.
(12) Spark timing incorrect.
(13) Vapor lock in fuel lines.
(15) Fuel solenoid fault

Question 22

What are possible cuases that would cause an engine to surge?

Answer 22

(1) Carburetor flooding.

(2) Governor spring hooked into wrong hole in lever, or governor rod incorrectly

Question 23

What is the initial adjustment you make to the low-speed air/fuel mixture?

Answer 23

Manufacturers reccomendation

Question 24

What method of air/fuel ratio adjustments gives you the best results?

Answer 24

Vacuum guage method.

Question 25

When do you make final valve adjustments?

Answer 25

After the engine reaches normal operating temperature

Question 26

What do you adjust on the breaker points to correct the gap?

Answer 26

Stationary contact

Question 27

Which engine component houses all of the internal components of the engine? a. Head. b. Block. c. Oil pan. d. Crankshaft.

Answer 27

B. Block

Question 28

Which engine component converts reciprocating motion, up and down, into rotary motion, round and round? a. Bearings. b. Camshaft. c. Crankshaft. d. Rocker arms.

Answer 28

C. Crankshaft

Question 29

Which engine component transfers the power of the piston to the crankshaft? a. Flywheel. b. Camshaft. c. Valve train. d. Connecting rod.

Answer 29

D. Connecting Rod

Question 30

The engine component that forms the top of the combustion chamber is the a. liner. b. block. c. piston. d. cylinder head.

Answer 30

D. Cylinder head

Question 31

The type of energy that the flywheel continually stores and releases to smooth the erratic operation of the engine is called a. heat. b. kinetic. c. hydraulic. d. pneumatic.

Answer 31

B. Kinetic

Question 32

Which term describes a complete series of events? a. Cycle. b. Stroke. c. Scavenging. d. Compression ratio.

Answer 32

A. cycle

Question 33

The position of the piston when it is at the highest point in its movement is best described by which term? a. Scavenging. b. Valve overlap. c. Top dead center (TDC). d. Bottom dead center (BDC).

Answer 33

C. top dead center (TDC)

Question 34

Which term describes the position of the piston when it is at the lowest point in its movement? a. Scavenging. b. Valve overlap. c. Top dead center (TDC). d. Bottom dead center (BDC)

Answer 34

D. bottom dead center (BDC)

Question 35

Which term describes the amount of time that both the intake and exhaust valves are open at the same time? a. Cycle. b. Scavenging. c. Valve overlap. d. Compression ignition.

Answer 35

Valve overlap

Question 36

In a diesel engine, how high does the compression of the air causes the temperature to rise? a. 120oF. b. 212oF. c. 500oF. d. over 1,000oF.

Answer 36

D. Over 1000 degrees F.

Question 37

On a two stroke engine, what creates the movement of intake air? a. Blower. b. Vacuum. c. Centrifugal force. d. Atmospheric pressure.

Answer 37

A. Blower

Question 38

On a four stroke engine, what is the position of the valves and how is the piston moving during the exhaust event? a. Both valves closed and the piston moving upward. b. Both valves open and the piston moving downward. c. Intake valve closed, exhaust valve open, and the piston moving upward. d. Intake valve open, exhaust valve closed, and the piston moving downward.

Answer 38

c. Intake valve closed, exhaust valve open, and the piston moving upward.

Question 39

Identify the component that provides an electrical spark in the combustion chamber at the proper time to ignite the air/fuel mixture. a. Carburetor. b. Spark plug. c. Distributor cap. d. Ignition system.

Answer 39

D. Ignition System

Question 40

Which component prevents the voltage in an ignition system from arcing across the breaker points, causing them to burn? a. Coil. b. Magnetic. c. Condenser. d. Distributor.

Answer 40

C. Condenser

Question 41

Identify a restriction in the passage of a carburetor that causes air to move faster. a. Jets. b. Nozzle. c. Venturi. d. Throttle.

Answer 41

C. Venturi

Question 42

What causes a four stroke gasoline engine to operate in a lean condition? a. An excess of fuel. b. An excess of oil. c. An excess of air. d. Not have enough oil.

Answer 42

C. An excess of air.

Question 43

Which troubleshooting choice is not a probable cause that a gasoline engine will not crank? a. Short in electrical wiring. b. Engine flooded. c. Battery is low. d. Faulty starter.

Answer 43

C. Battery is low

Question 44

Identify the type of malfunction that occurs if a gasoline engine’s ignition firing order is incorrect. a. Engine backfires through the carburetor. b. Engine will not crank. c. Engine overheating. d. Engine knock.

Answer 44

A. Engine backfires through the carburetor.

Question 45

What do you use to check the gap of breaker points to make sure it is at the specified distance? a. Ruler. b. Caliper. c. Thickness gauge. d. Inside micrometer.

Answer 45

C. Thickness Gauge

Question 46

Which item fits into irregularities that exist on surfaces as you connect two engine components during engine maintenance? a. Gaskets. b. Wedges. c. Lock tight. d. Sealing compound.

Answer 46

A. Gaskets

Question 47

Identify the reason you inspect a vibration dampener during engine maintenance. a. Security only. b. Cracks and chips only. c. Security, cracks, and chips. d. Security, paint, cracks, and chips.

Answer 47

C. Security, cracks, and chips