Deck 18: Diesel Fuel Characteristics

Question 1

Which organization is responsible for classifying diesel fuel to a standard?

A) SAE
B) API
C) ATA
D) ASTM

Answer 1

ASTM

Question 2

Which of the following terms describes the amount of heat energy in a fuel?

A) calorific value
B) cetane number
C) fire point
D) volatility

Answer 2

calorific value

Question 3

Which of the following acronyms is commonly used to describe the actual ratio of fuel and air in a combustion reaction?

A) ASTM
B) AFR
C) SSU
D) RON

Answer 3

AFR

Question 4

Which of the following acronyms defines the ignition quality of a diesel fuel?

A) CNG
B) RON
C) MON
D) CN

Question 5

Which of the following terms is used to describe the anti-knock ability of a gasoline?

A) cetane number
B) fire point
C) oxidation stability
D) octane rating

Question 6

Which two compounds are necessary for the formation of photochemical smog?

A) nitrogen and oxygen
B) NOx and HC
C) sulfur and carbon dioxide
D) H₂O and SO₂

Question 7

What is the source of 60% of the energy consumed in North America?

A) hydro electricity
B) coal
C) petroleum
D) nuclear fusion

Question 8

Which is the most efficient method of separating the highest fractions found in crude petroleum?

A) distillation
B) vaporization
C) thermal cracking
D) catalytic cracking

Question 9

Which of the following compounds is a commonly used diesel fuel ignition accelerator?

A) cetane
B) butane
C) cyclohexanol nitrate
D) propane

Question 10

Which of the following values is used to measure the heat energy (calorific value) in a fuel?

A) BTU
B) BHP
C) CNG
D) RON

Question 11

What is the maximum sulfur content permitted in a diesel fuel approved for use on North American highways?

A) 0.335% S
B) 0.250% S
C) 0.05% S
D) 0.0015% S

Question 12

What is the maximum sulfur content in a diesel fuel classified as ultralow sulfur (ULS) in North America?

A) 300 ppm
B) 500 ppm
C) 50 ppm
D) 15 ppm

Question 13

What substance is commonly added to truck diesel fuel tanks to prevent winter freeze up?

A) ethylene glycol
B) alcohol
C) dispersants
D) antifreeze

Question 14

What is the lowest CN value that any #1D or #2D fuel formulated for highway use can be legally sold at?

A) 38
B) 40
C) 45
D) 47

Question 15

What is the main ingredient found in a diesel fuel conditioner?

A) alcohol
B) cetane improver
C) cleaning additives
D) pour point depressant

Question 16

Technician A says that ULS is now mandatory for all on-highway diesel engine applications. Technician B says that ULS is now mandatory for all off-highway mobile diesel engines. Who is correct?

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

Question 17

Which of the following diesel fuels is most commonly used to fuel highway trucks in North America?

A) #1D clear
B) #2D clear
C) #2D red
D) #2D blue

Question 18

Which of the following terms describes the tendency of a liquid to vaporize?

A) volatility
B) combustibility
C) condensivity
D) viscosity

Question 19

A substance that enables a chemical reaction without itself undergoing any change is known as a:

A) fraction
B) catalyst
C) polymer
D) reactant

Question 20

Which of the following would be a typical specific gravity rating of a #2D diesel fuel?

A) 0.557
B) 0.675
C) 0.825
D) 1.225

Question 21

What is the specific gravity at 15 degrees Celsius of a diesel fuel with an API gravity of 37 degrees?

A) 0.8398
B) 0.8137
C) 0.7988
D) 0.7890

Question 22

Technician A says that diesel fuel in a vehicle tank can degrade when exposed to high temperatures. Technician B says that the most volatile fractions in a diesel fuel are the ones that define the CN of the fuel. Who is correct?

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

Question 23

Technician A says that fuel costs are second only to tires when reviewing the operating expenses of trucks on our highways. Technician B says that as fuel costs rise, this provides a competitive advantage to large fleets over individual-owner operators. Who is correct?

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

Question 24

Technician A says that by delaying refueling of truck diesel fuel tanks until the moment of departure, engine fuel problems can be minimized by ensuring that engines are always using freshest fuel. Technician B says that refueling truck diesel tanks on return from a journey is wasteful as some fuel will boil off from tanks left overnight. Who is correct?

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

Question 25

Technician A says that biodiesel has a short shelf life compared with petroleum sourced diesel fuel. Technician B says that degraded biodiesel can result in costly fuel problems. Who is correct?

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