Deck 39: Fuels and Alternative Fuels

Question 1

11)While having a discussion, Technician A says that carbonaceous deposits are caused when oil and heat come together. Technician B says that carbonaceous deposits are from fuel. Who is correct?

A) A only
B) B only
C) Both A and B
D) Neither A nor B

Answer 1

B

Question 2

2)With gasoline octane ratings, the lower the octane number, the more resistant the fuel is to knocking.

Answer 2

False

Question 3

3)Water is an enemy to diesels and must not be allowed to accumulate in the fuel system.

Answer 3

True

Question 4

18)____________________ is a measure of how easy a fuel evaporates.

Question 5

14)Which of the following statements is LEAST-Likely true?

A) A major disadvantage to alcohol fuels when compared to gasoline is that they are invisible when burning.
B) Methanol is very corrosive and is poisonous.
C) LPG is mostly butane.
D) Methanol attacks aluminum, some plastics, and other materials.

Question 6

12)Gasoline can be refined so it will not knock as easily. This fuel has a high ____ value.

A) dieseling
B) LPG
C) ethanol
D) octane

Question 7

5)Unlike preignition, detonation does not produce a knocking sound, so the impending damage is not apparent until it is too late.

Question 8

10)The term MOST-Likely used to describe the event where air-fuel mixture self-ignites due to increased pressure in the cylinder is:

A) noise
B) preignition
C) detonation
D) dieseling

Question 9

20)When a gasoline engine continues to run even after the ignition key is turned off, this is called ____________________.

Question 10

7)Which of the following statements is LEAST Likely true?

A) More frequent oil changes are required with diesels.
B) Under a heavy load, a diesel makes soot, which is abrasive and is hard on engine parts.
C) While heavy trucks have transmissions with many gears and are designed to pull heavy loads, passenger cars have only the normal number of gear ranges.
D) Diesels generally have a smaller capacity oil pan.

Question 11

15)The term MOST-Likely used to describe an ideal fuel, that produces no emissions other than water and carbon dioxide is:

A) liquefied natural gas
B) hydrogen
C) liquefied petroleum gas
D) compressed natural gas

Question 12

19)A car's ____________________ on the highway is a symptom of a lean condition.

Question 13

8)When the air-fuel mixture is ignited during normal combustion, a ____ travels across the combustion chamber and pushes the piston down in the cylinder.

A) surge
B) flame front
C) spark
D) run-on

Question 14

17)The ____________________ of a diesel fuel describes how easily the fuel will ignite.

Question 15

9)While having a discussion, Technician A says that the noise from spark knock is caused by the vibration of the combustion chamber walls. Technician B says that it is caused by low volatility. Who is correct?

A) A only
B) B only
C) Both A and B
D) Neither A nor B

Question 16

13)All of the following statements are true EXCEPT:

A) LPG tends to settle out as a liquid in the intake manifold.
B) LPG has a higher octane; therefore, it can be used in engines with higher compression ratios.
C) less frequent oil change intervals are required because LPG is a dry gas so it does not create carbon in the combustion chamber.
D) LPG burns cleanly, produces fewer emissions, and lacks the objectionable exhaust odor of incompletely burned gasoline.

Question 17

6)All of the following statements are true EXCEPT:

A) diesel engines burn diesel oil as fuel.
B) a diesel has a very low-compression ratio.
C) diesel fuel is light oil that is refined as part of the same process that makes gasoline.
D) a diesel engine is called a compression ignition engine.

Question 18

1)Crude oil is a variable combination of large and small hydrocarbons together with petroleum gas, hydrogen sulfide, and water.

Question 19

4)Although biodiesel is cleaner burning than petroleum diesel, pure biodiesel (B100) requires fuel system modifications on pre-1994 diesel engines.

Question 20

16)Diesel fuels contain some paraffin (wax). In very cold weather, the paraffin can separate from the fuel. This is called the ____________________.

Question 21

22)What are the results of low volatility?

Question 22

23)What are some of the problems that can occur as a result of vapor lock?

Question 23

24)What are some of the possible causes of preignition?

Question 24

21)What is the difference between the following two grades for automotive diesel fuel: Grade number 1-D and Grade number 2-D?

Question 25

25)What are the disadvantages of LPG?