Question 1

What is used to cool an air-to-air charge air cooler?

Accepted Answer

A)  ram air 
B)  engine coolant 
C)  engine lubricant 
D)  engine fan 
A)  ram air 
B)  engine coolant 
C)  engine lubricant 
D)  engine fan A

Question 2

What would be a typical maximum intake restriction specification for a naturally aspirated diesel engine?

Accepted Answer

A)  15 inches H2O 
B)  15 inches Hg 
C)  25 inches H2O 
D)  25 inches Hg 
A)  15 inches H2O 
B)  15 inches Hg 
C)  25 inches H2O 
D)  25 inches Hg A

Question 3

When the unison ring in a variable nozzle (VN) type turbocharger is moved, which of the following changes?

Accepted Answer

A)  vane pitch 
B)  pulse frequency 
C)  inlet flow area 
D)  bypass flow area 
A)  vane pitch 
B)  pulse frequency 
C)  inlet flow area 
D)  bypass flow area A

Question 4

What is the functional difference between C-EGR and I-EGR?

Accepted Answer

A)  C-EGR system run warmer 
B)  I-EGR is managed within the cylinder head 
C)  I-EGR costs more 
D)  C-EGR systems must be managed by the engine ECM 
A)  C-EGR system run warmer 
B)  I-EGR is managed within the cylinder head 
C)  I-EGR costs more 
D)  C-EGR systems must be managed by the engine ECM

Question 5

What should be used to measure the radial play of a turbine shaft?

Accepted Answer

A)  micrometer 
B)  thickness gauges 
C)  digital calipers 
D)  dial indicator 
A)  micrometer 
B)  thickness gauges 
C)  digital calipers 
D)  dial indicator

Question 6

What would be a typical maximum intake restriction specification for a turbocharged diesel engine?

Accepted Answer

A)  15 inches H2O 
B)  15 inches Hg 
C)  25 inches H2O 
D)  25 inches Hg 
A)  15 inches H2O 
B)  15 inches Hg 
C)  25 inches H2O 
D)  25 inches Hg

Question 7

What happens when a wastegate actuator is in its default position?

Accepted Answer

A)  all exhaust gas bypasses the turbine housing 
B)  all exhaust gas is routed through the turbine housing 
C)  all intake air bypasses the charge air cooler 
D)  all intake air bypasses the compressor housing 
A)  all exhaust gas bypasses the turbine housing 
B)  all exhaust gas is routed through the turbine housing 
C)  all intake air bypasses the charge air cooler 
D)  all intake air bypasses the compressor housing

Question 8

Which of the following would ensure that the breathing efficiency of a pair of intake valves on one diesel engine cylinder was identical?

Accepted Answer

A)  air to air cooler 
B)  crossflow valve configuration 
C)  tune intake manifold 
D)  parallel port valve configuration 
A)  air to air cooler 
B)  crossflow valve configuration 
C)  tune intake manifold 
D)  parallel port valve configuration

Question 9

Which of the following is NOT part of the exhaust system?

Accepted Answer

A)  catalytic converter 
B)  turbocharger 
C)  pyrometer 
D)  charge air cooler 
A)  catalytic converter 
B)  turbocharger 
C)  pyrometer 
D)  charge air cooler

Question 10

Which type of valve configuration is more likely to be used with quiescent combustion technology?

Accepted Answer

A)  parallel port 
B)  series-parallel 
C)  crossflow 
D)  two valve per cylinder 
A)  parallel port 
B)  series-parallel 
C)  crossflow 
D)  two valve per cylinder

Question 11

In a sound absorption type muffler, what is sonic energy converted to?

Accepted Answer

A)  friction, then heat 
B)  mechanical vibration 
C)  pressure 
D)  noise 
A)  friction, then heat 
B)  mechanical vibration 
C)  pressure 
D)  noise

Question 12

Which of the following specs is the usual start-test spec when testing an air-to-air, boost air heat exchanger?

Accepted Answer

A)  5 psi 
B)  15 psi 
C)  30 psi 
D)  50 psi 
A)  5 psi 
B)  15 psi 
C)  30 psi 
D)  50 psi

Question 13

What is the function of the stainless steel liner used in the cylinder head exhaust tract of some diesel engine cylinder heads?

Accepted Answer

A)  insulation to maximize rejected heat discharge to the turbine housing 
B)  helps protect service personnel from serious burns 
C)  enables high sulfur fuel to be combusted in electronically controlled diesel engines 
D)  all of the above 
A)  insulation to maximize rejected heat discharge to the turbine housing 
B)  helps protect service personnel from serious burns 
C)  enables high sulfur fuel to be combusted in electronically controlled diesel engines 
D)  all of the above

Question 14

What term does Detroit Diesel use to describe their compound turbocharger on DD-series engines?

Accepted Answer

A)  variable geometry (VG) 
B)  pulsed turbocharging 
C)  direct drive turbocharging 
D)  axial power turbine (APT) 
A)  variable geometry (VG) 
B)  pulsed turbocharging 
C)  direct drive turbocharging 
D)  axial power turbine (APT)

Question 15

Which of the following is NOT an intake system component?

Accepted Answer

A)  charge air cooler 
B)  air cleaner 
C)  turbocharger 
D)  catalytic converter 
A)  charge air cooler 
B)  air cleaner 
C)  turbocharger 
D)  catalytic converter

Question 16

Which of the following is the most accurate method of checking out an air filter between service intervals?

Accepted Answer

A)  remove and test with a trouble light 
B)  test with a manometer 
C)  blow out with an air nozzle 
D)  tap on floor to loosen dust 
A)  remove and test with a trouble light 
B)  test with a manometer 
C)  blow out with an air nozzle 
D)  tap on floor to loosen dust

Question 17

Which of the following components usually makes detailed tuning of diesel engine intake manifolds unnecessary?

Accepted Answer

A)  charge air cooler 
B)  precleaner 
C)  positive air cleaner 
D)  turbocharger 
A)  charge air cooler 
B)  precleaner 
C)  positive air cleaner 
D)  turbocharger

Question 18

What is the critical flow area inside the turbine housing of a turbocharger known as?

Accepted Answer

A)  diffuser 
B)  impeller gate 
C)  volute 
D)  turbine outlet 
A)  diffuser 
B)  impeller gate 
C)  volute 
D)  turbine outlet

Question 19

Technician A says that a DD axial power turbine (APT) uses a constant geometry (CG) turbine principle. Technician B says that Detroit Diesel claim their APT can add over 100 horsepower to engine output potential. Who is correct?

Accepted Answer

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

Question 20

What is the housing containing the muffler, catalytic converters, SCR, and diesel particulate filter (DPF) known as?

Accepted Answer

A)  exhaust pipe 
B)  engine silencer 
C)  resonator housing 
D)  exhaust gas aftertreatment canister 
A)  exhaust pipe 
B)  engine silencer 
C)  resonator housing 
D)  exhaust gas aftertreatment canister

Exam 12: Engine Breathing

What is used to cool an air-to-air charge air cooler?

What would be a typical maximum intake restriction specification for a naturally aspirated diesel engine?

When the unison ring in a variable nozzle (VN) type turbocharger is moved, which of the following changes?

What is the functional difference between C-EGR and I-EGR?

What should be used to measure the radial play of a turbine shaft?

What would be a typical maximum intake restriction specification for a turbocharged diesel engine?

What happens when a wastegate actuator is in its default position?

Which of the following would ensure that the breathing efficiency of a pair of intake valves on one diesel engine cylinder was identical?

Which of the following is NOT part of the exhaust system?

Which type of valve configuration is more likely to be used with quiescent combustion technology?

In a sound absorption type muffler, what is sonic energy converted to?

Which of the following specs is the usual start-test spec when testing an air-to-air, boost air heat exchanger?

What is the function of the stainless steel liner used in the cylinder head exhaust tract of some diesel engine cylinder heads?

What term does Detroit Diesel use to describe their compound turbocharger on DD-series engines?

Which of the following is NOT an intake system component?

Which of the following is the most accurate method of checking out an air filter between service intervals?

Which of the following components usually makes detailed tuning of diesel engine intake manifolds unnecessary?

What is the critical flow area inside the turbine housing of a turbocharger known as?

Technician A says that a DD axial power turbine (APT) uses a constant geometry (CG) turbine principle. Technician B says that Detroit Diesel claim their APT can add over 100 horsepower to engine output potential. Who is correct?

What is the housing containing the muffler, catalytic converters, SCR, and diesel particulate filter (DPF) known as?

Introduction

Hand and Shop Tools, Precision Tools, and Units of Measurement

Personal and Safety Awareness

Engine Basics

History of the Heat Engine

Power

Engine Powertrain Components

Engine Feedback Assembly

Engine Housing Components

Engine Lubrication Systems

Engine Cooling Systems

Engine Retarders

Servicing and Maintenance

Engine Removal, Disassembly, Cleaning,

Diesel Engine Run- in and Performance Testing

Chemistry and Combustion

Diesel Fuel Characteristics

Fuel Subsystems

Fuel Injection Basics and Governor Principles

Injector Nozzles

Port-Helix Metering Injection Pumps

Inlet-Metering Rotary Distributor Pumps

Sleeve-Metering Rotary Distributor Pumps

Single-Actuator Eui Systems

Dual-Actuator Eui Systems

Heui Fuel Systems

Electronic Unit Pump Eup Systems

Cummins Hpi-Tp

Common Rail Systems

Amplified Common Rail Systems

Review of Electrical and Electronics Fundamentals

Vehicle Computer Systems

Ests and Siss

Electrical Wiring, Connector Terminal Repair

Multiplexing

The Connected Vehicle

Natural Gas, Propane, and Biodiesel Fuels

High Voltage Electricity

Hybrid and Hydrogen Fuel Cell Drivetrains

Electric Powertrains

Bosch Edc Systems

Caterpillar Engine Management Systems

Cummins Management Systems

Detroit Diesel Electronic Controls Ddec

Navistar Diamond Logic

Paccar Engine Management Systems

Volvo and Mack Engine Management

Emissions Management

Servicing Maintenance of Exhaust Aftertreatment Systems

Failure Analysis

Troubleshooting and Diagnostics

Filters