Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

OTC - AD Electrical and Electronic Systems > otc_-_deisel_electrical_det-106_20171012120006 > Flashcards

otc_-_deisel_electrical_det-106_20171012120006 Flashcards

1
Q

When an incandescent light bulb is energized in an electrical circuit, what is electrical energy converted to?

A

heat and light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the function of a headlamp dimmer switch?

A

switches headlamps between separate low-and high-beam circuits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What type of headlight fires an arc through gas to produce light energy?

A

HID

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which of the following best explains the construction of a halogen headlamp element?

A

tungsten filament encased in a quartz envelope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How much voltage is required to sustain the arc in a typical HID headlamp assembly?

A

around 85 volts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which of the following best defines light energy?a. heat b. photons c. electrons d. protons

A

photons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which of the following would be used to switch turn lights on a truck chassis?a. stalk switch b. headlamp switch c. brake pressure switch d. toggle switch

A

stalk switch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How many contacts are in a typical tractor-to-trailer electrical connector?

A

seven

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What color code is used for the brake light circuit in a truck trailer electrical connector?

A

red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

When truck and trailer clearance lights and headlamps seem to burn out at a high rate, which of the following would be a required step in troubleshooting?a. voltage losses in ground circuit b. battery state of charge c. battery surface charge d. charging system voltage regulator

A

charging system voltage regulator

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What governs highway truck exterior lighting standards in North American trucks?

A

FMVSS 108

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In a standard SAE relay, which of the following is normally open (NO)?a. 7 b. 4 c. 5 d. 3

A

5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

In an older standard SAE relay, what pair of terminals energizes the coil circuit?

A

85 and 86

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

The headlights on a truck with electromechanical controls and circuit breaker protection continuously illuminates for a short period and then cut out. Technician A says that if the circuit breaker is a type 1, replacing it with a type 2 should repair the problem. Technician B says that the problem is likely caused by a malfunction in a type-2 circuit breaker. Who is correct?

A

Neither A nor B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Technician A says that on a standard SAE relay, terminal 3 is always the common terminal. Technician B says that in a standard SAE relay, the coil circuit must be energized to close the normally open 5 terminal. Who is correct?

A

Both A and B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the maximum acceptable total voltage drop across all of the terminals and cables on the insulated side of a cranking circuit?

A

0.5 volt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Technician A says that a corroded light unit terminal could result in an increased voltage drop across the terminal. Technician B says that a corroded light unit terminal could result in heat at the terminal. Who is correct?

A

Neither A nor B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Technician A says that a disadvantage of using LEDs as stoplights is that when the circuit is switched on, they illuminate at a slower speed than incandescent bulbs. Technician B says that xenon headlamps are a disadvantage in trucks because they have a shorter service life than halogen bulbs. Who is correct?

A

Neither A nor B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What type of filament is used in a halogen headlight?

A

tungsten

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Technician A says that HID headlamps consume more electrical power than equivalent halogen headlamps. Technician B says that HID headlamps are brighter and their blue light is more similar to natural sunlight than that of halogen lamps. Who is correct?

A

Technician B only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What EST is used to read flash codes?

A

dash diagnostic lights

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

The appropriate EST for performing a resistance test on a potentiometer-type TPS isolated from its circuit is what?

A

DMM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the correct means of electronically coupling a HH-EST with a truck chassis ECM?

A

chassis data connector

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

When resistance and continuity tests are made on electronic circuit components, the circuit being tested should be:a. energized b. open c. closed

A

open

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

DMM test lead resistance should never exceed:a. 100 ohms b. 10 ohms per inch c. 1.0 ohm a. 0.2 ohm

A

1.0 ohm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the output (signal) of a pulse generator rotational speed sensor measured in?

A

V-AC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Which of following cannot usually be performed by a generic HH-EST?a. proprietary data programming b. snapshot testing c. customer data programming d. erase historic fault codes

A

proprietary data programming

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Which of the following procedures cannot be performed using a PC and the OEM software?a. solenoid cycle tests b. permanently erase active fault codes c. customer data programming d. erase historic fault codes

A

permanently erase active fault codes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Which of the following methods is commonly used to upgrade the software on handheld ESTs?a. replace the RAM chip b. reprogram the software cartridge from a mainframe b. upgrade the cartridge PROM chips or cards d. Replace the docking head

A

upgrade the cartridge PROM chips or cards

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Which FMI should be displayed when reading an open TPS circuit?

A

5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

How many counts of resolution can be displayed by a 41/2-digit DMM?

A

19,999

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

The specification that indicates how fine a measurement can be made by a DMM is known as what?

A

resolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

When a DMM is set to read AC, which is the term used to describe the averaging of potential difference to produce a meter reading?

A

root mean square (rms)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Which port on an HH-EST data connector is used to connect the printer?

A

RS-232 port

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What components are inserted into terminal sockets to enable testing by KMM probes and minimize physical damage?

A

terminal dummies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Which electrical voltage value does a DMM output when in diode test mode?

A

0.6V

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Technician A states that the accuracy of an analog meter is usually no better than 3 percent. Technician B states that most DMMs have an accuracy factor that is within 0.1 percent of the reading. Who is correct?a. neither A nor B b. both A and B c. Technician A only Technician B only

A

Both A and B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is the component called that can be safely inserted into electronic circuits so that they can be tested without interrupting them?

A

breakout box

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Technician A states that using the snapshot test mode when using a handheld reader/programmer to troubleshoot an intermittently occurring fault code will help identify the conditions that produced the code. Technician B states that snapshot test mode can only analyze a historic code. Who is correct?a. neither A nor B b. Both A and B c. Technician B only d. Technician A only

A

Technician A only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

When verifying the signal produced by a potentiometer-type TPS, the DMM test mode selected should be, what?

A

V-AC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Describe the difference between an active code and a historic code

A

An ACTIVE code exists at the time of viewing: A HISTORIC code is INACTIVE at the time of viewing and is logged in memory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What is meant by the term GUI? Give some examples.

A

A GUI is a graphical user interface: its best example is in the pictorial ICONs used in Widows, and Mac software.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is meant by the term networking?

A

The term NETWORKING is used generally to refer to two or more computer systems that can communicate with each other. On a truck, the data bus or backbone is the networking medium. The Internet is one means that enable PCs to network.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Which of the following PC components would be usually described as a peripheral?a. system housing b. hard disk drive c. CPU d. Printer

A

Printer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

In a PC is to be networked to the Internet or an OEM data Hub, which of the following devices is usually required? a. a CD drive b. a digital camera c. speakers d. a modem

A

a modem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Which of the following J1587 identifiers is equivalent to a J1939 suspect parameter number (SPN)?a. SA b. FMI c. PID a MID

A

PID

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Technician A says that a J1939 SA is a module with an address on the data bus. Technician B says that J1587 FMIs are identical in number to J1939 FMIs. Who is correct?

A

Technician A only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Which of the following is the J1939 equivalent of the J1587 MID?a. SPN b. SA c. FMI d. PGN

A

SA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What color is the 2013 J1939 data connector?

A

Green

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Technician A says that the post-2013 J1939 data connector is backward compatible with pre-2013 data connectors. Technician B says the F-pin on a post-2013 J1939 data connector is smaller than that on a pre-2013 data connector. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. neither A nor B

A

Both a and B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What is the tool of choice to accurately check the inlet restriction of a dry air filter?

A

water-filled manometer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What is a typical maximum specified inlet restriction for an air filter on a turbocharged diesel?

A

25 inches H2O restriction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Which of the following types of air filters has the highest filtering efficiencies?a. Centrifugal precleaners b. Dry, positive c. Dry, non-positive d. Oil bath

A

Dry, positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Which of the following should be performed first when checking an engine that produces black smoke under load?a. Injection timing b. Air filter restriction test c. Plugged DPF d. Fuel quality by chemical lab analysis

A

Air filter restriction test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Which of the following best describes the intended function of a C-EGR system on a diesel engine?a. It assists the turbocharger in boosting intake pressure b. It increases engine breathing efficiency c. It dilutes the intake charge with cooled dead gas d,. It preheats the intake charge to the cylinder

A

It dilutes the intake charge with cooled dead gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What best describes the function of a wastegate in a current turbo-boosted diesel engine?

A

Allows exhaust gas to bypass the turbine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

When series turbocharging is used on a current diesel engine, which of the following should be true?a. Twin turbos are arranged in parallel b. Intake air must pass through the turbine housing of both turbos c. Exhaust gas must pass through the turbine housing of both turbos c. The VG actuator is in series with the EGR mixer

A

Exhaust gas must pass through the turbine housing of both turbos

58
Q

What is the critical flow area managed by a VG turbo using a variable nozzle operating principle?

A

Turbine volute

59
Q

To produce peak manifold boost from a VN-type turbocharge, which of the following should be true?a. Wastegate is fully closed b. Wastgate is fully open c. Vanes are in the nearly closed position d. Vance are in the fully open position

A

Vanes are in the nearly closed position

60
Q

The constant geometry turbocharger used in a highway diesel engine with turbo corresponding is usually designed to produce optimum efficiency at which rpm?

A

Rated speed and load

61
Q

Technician A states that a dry air filter functions at optimum entrapment efficiency when it is new and that by the time it requires replacing, it has lower filtering efficiencies. Technician B states that oil bath filters are seldom used with today’s highway diesel engines because they have low filtering efficiencies. Who is correct?a. Technician A b. Technician B c. Both A and B d. Neither A nor B

A

Technician B only

62
Q

Technician A states that turbo-compounded diesel engines such as the DDC DD15 use CG turbos to supply boost air to the intake manifold. Technician B states that turbo compounding allos the turbo to directly contribute drive torque to the engine drivetrain by means of reduction gearing. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Both A and B

63
Q

Technician A states that the term “manifold boost” is used to describe breathing on a turbocharged engine. Technician B states that turbine speeds on truck diesel engines can exceed 100,000 rpm. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Both A and B

64
Q

Technician A states that using a light bulb inside an air filter element is a reliable means of determining whether the filter is plugged. Technician B states that air filters are vest left untouched between service intervals unless the filter restriction gauge indicated an out-of-specification reading. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Technician B only

65
Q

Technician A states that the first item to be checked when an engine produces black smoke should be the air filter inlet restriction gauge. Technician B states that whenever an engine produces black smoke, the air filter should automatically be changed. Who is correct?

A

Technician A only

66
Q

Which of the following methods would identify the location of a hole or tear in an air filter element?a. Air inlet restriction gauge b. Lightbulb test c. Regulated air pressure test d. Manometer test

A

Lightbulb test

67
Q

When is a diesel engine turbocharger capable of highest rotational speeds?

A

When rejected heat is greatest

68
Q

Which of the following components would be located in a diesel exhaust gas aftertreatment canister?a. SCR b. DPF c. Oxidation converter d. Any or all of the above

A

Any or all of the above

69
Q

Which of the following best describes the function of a VG turbocharger?a. It reroutes NOx back into the engine cylinders b. It reroutes EGR gas into the DPF c. It behaves like a large turbocharger when engine load is high d. It behaves like a small turbocharger when engine load is high

A

It behaves like a large turbocharger when engine load is high

70
Q

Technician A states that the function of a turbocharger wastegate is a divert exhaust gas around the turbine directly into the exhaust system. Technician B states that a wastgated turbocharger can improve turbine efficiencies at lower loads and rpms. who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Both A and B

71
Q

Who invented the first heat engine?

A

Hero

72
Q

Which of the following properly describes the first heat engine?a. Internal combustion b. Reaction turbine c. Two-stroke cycle d. Four-stroke cycle

A

Reaction turbine

73
Q

Who invented the term horsepower?

A

Watt

74
Q

Who built the world’s first useful steam engine?

A

Savery

75
Q

Who designed the first centrifugal governor?

A

Watt

76
Q

In what year did Diesel patent his compression ignition engine?

A

1892

77
Q

Who patented the first high-pressure liquid fuel injection pump for a diesel engine?

A

Bosch

78
Q

Who is known as the “father of the highway diesel engine”?

A

Cummins

79
Q

What are the U.S. inventors Eckert and Mauchly known for?

A

The first electronic digital computer

80
Q

The world’s first automobile was built by who?

A

Cugnot

81
Q

Calculate the brake power of an engine producing 1,150 lb-ft. of torque at the flywheel when it is turning at 2,000 rpm.

A

438 BPH

82
Q

Use the PLANC formula to calculate the indicated power of a six-cylinder, fourstroke cycle engine run at 1,800 rpm using the following data:Stroke: 6.0 inchesBore: 5.5 inchesMEP: 220 psi

A

428 BHP

83
Q

Which of the following is required to produce peak torque in a diesel engine?a. Peak volumetric efficiency b. Peak mechanical efficiency c. Peak brake power d. Peak cylinder pressure

A

Peak cylinder pressure

84
Q

In most hydromechanical fuel systems, when maximum engine rpm is increased, the engine brake power potential will also increase. True or False?

A

True

85
Q

Which of the following statements helps explain why an engine develops peak brake power at a higher rpm than peak torque?a. Volumetric efficiency is better at high rpm b. There is more time for combustion c. More power strokes per second occur d. Cylinder pressures are highest

A

More power strokes per second occur

86
Q

Which of the following is true of an engine described as having high torque rise when comparing it with its standard version with the same nominal rated power?a. It will provide a wider operating rpm range b. It will be more fuel efficient c. It will produce higher brake power d. It will have a higher maximum speed

A

It will provide a wider operating rpm range

87
Q

A group of cyclists all weighing 175 lbs (80 kg) and riding on bicycles of equal weight ride a 6.4-mile (10-kilometer) race and all finish it. Which of the cyclists has performed the most work?a. The winner b. The loser c. All have performed equal work

A

All have performed equal work

88
Q

Usable power at the flywheel of an engine is know as what?

A

Brake power

89
Q

When engine power is calculated rather than tested, it is know as what?

A

Indicated power

90
Q

Which of the following expresses 1 HP correctly?a. 550 lb-ft. of work per second b. 5,252 lb-ft. of work per minute c. 33,000 lb-ft. of work per second

A

550 lb-ft. of work per second

91
Q

Convert a torque value of 25 lb-ft. into Newton-meters

A

33.9

92
Q

A Cummins ISX 11.9 liter engine, programmed to 330 HP, produces a peak torque value of 1,350 lv-ft. at 1,300 rpm. Convert the torque value to Newton-meters.

A

1,830 N.m

93
Q

A Detroit Diesel DD16 is rated at 600 HP. Express this in kilowatts.

A

448 kW

94
Q

A Navistar MaxxForce 13 produces 355 kW of power at 1,800 rpm. Convert the kW to an HP value.

A

475 HP

95
Q

When comparing truck engine brake power measured at the flywheel to that measured at the drive wheels, which one of the following should be true about brake power?a. There is no difference if the transmission and drive carrier are functioning properly.b. Power at the flywheel exceeds that at the drive wheels by 20% to 25%c. Power at the wheels exceeds that at the flywheel by 10% to 25%d. Power can only be measured at the drive wheels

A

Power at the flywheel exceeds that at the drive wheels by 20% to 25%

96
Q

Which of the following engine conditions would be the likely cause of a tensile failure of a connecting rod?a. Prolonged lug downb. Prolonged engine idlingc. Engine overspeedd. High cylinder pressures

A

Engine overspeed

97
Q

Which of the following is a disadvantage of an articulating piston assembly when compared to an aluminum alloy trunk piston?a. Piston slap controlb. Highest possible location of an upper ring groovec. Service lifed. Increased tensile loading on the connecting rods

A

Increased tensile loading on the connecting rods

98
Q

Where would a Ni-Resist insert be located?

A

Upper ring belt, aluminum trunk position

99
Q

Under which of the following conditions would a piston ring seal more effectively?a. High cylinder pressuresb. Low cylinder pressuresc. High engine temperaturesd. Low engine temperatures

A

High cylinder pressures

100
Q

A crankshaft has a fracture failure that appears to have initiated at a throw journal oil hole. Which of the following would be the most likely cause?a. A failed vibration damperb. A spun rod bearingc. A broken main capd. Excessive cylinder pressure

A

A failed vibration damper

101
Q

Which of the following journal surface hardening methods would provide the highest machinability margin?a. Induction hardeningb. Flame hardeningc. Nitriding d. Shot peening

A

Induction hardening

102
Q

Rod and main journal bearing clearances are properly measured with what?

A

Plastigage

103
Q

What type of piston is favored by diesel engine OEMs in post-2007 products?

A

Forged steel trunk

104
Q

When observing a disassembled engine, the outer crown edges of all six pistons show signs of melting and erosion. This could be cause by what?a. Fuel with high sulfur contentb. Advanced timingc. retarded timingd. a dribbling injector

A

Advanced timing

105
Q

Which of the following types of pistons use brushingless pin bosses?a. Aluminum alloyb. Crossheadc. Monothermd. Ferrotherm

A

Monotherm

106
Q

What would be the consequence of a misdirected piston oil cooling jet?a. Overheated engine lubeb. Fuel in the lubec. Low oil pressured. Torched piston

A

Torched piston

107
Q

Technician A states that keystone rings are most common in current diesel engines. Technician B states that keystone connecting rods have a wedge-shaped big end. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Technician A only

108
Q

What should be used to install piston rings onto a piston?

A

A ring expander

109
Q

Which of the following operating modes would be more likely to result in a compressional failure of a connecting rod?a. Prolonged low idle runningb. Prolonged high idle runningc. Hydraulic lock caused by head gasket failured. Overspeeding engine

A

Hydraulic lock caused by head gasket failure

110
Q

Which of the following would be the more likely outcome of running an engine with a failed vibration damper?a. Crankshaft failureb. Camshaft failurec. Increased fuel consumptiond. Increased cylinder blowby

A

Crankshaft failure

111
Q

Into what area of a Mexican hat combustion chamber are the injected droplets of fuel directed?

A

Crater

112
Q

The upper face of a piston assembly is called what?

A

Crown

113
Q

Technician A states that a cam ground piston is circular when cold and expands to an elliptical shape at operating temperature. Technician B states that the reason the cam ground piston is elliptical when cold is to accommodate the thermal expansion of the greater mass of material at the piston boss as it is raised to operating temperature. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Technician B only

114
Q

The piston crown design most commonly used by OEMs in today’s highway diesel engines is the:a. Barrel faceb. Mexican hatc. Mann typed. Dished

A

Mexican hat

115
Q

What term is used to describe the cylinder volume between the piston upper compression ring and its leading edge?

A

Headland volume

116
Q

Which of the following is true of a CFA piston?a. The ring belt operates at higher temperaturesb. It is used only on articulating pistonsc. It is type of Ni-Resist insertd. The ring belt reinforcement insert extends up into the leading edge of the piston

A

The ring belt reinforcement insert extends up into the leading edge of the piston

117
Q

When crankshaft thrust surfaces are reground, which of the following would be true?a. The thrust washers must be shimmed.b. The thrust washers must be machined to smaller dimensionc. Undersize thrust bearings are requiredd. Oversize thrust bearings are required

A

Oversize thrust bearings are required

118
Q

Technician A states that main bearing shells are usually interchangeable and may be installed in either the upper or lower position. Technician B states that the main bearing shell with an oil hole must always be installed in the main bearing cap. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Neither A nor B

119
Q

Excessive clearance at the crankshaft main bearings could result in which of the following conditions?a. High oil pressureb. Low oil pressurec. Aerated oild. Fluctuating oil pressures

A

Low oil pressure

120
Q

Technician A states that the type of vibration damper most commonly used on truck diesel engines is the viscous type. Technician B states that the inertia ring drive medium on a viscous-type vibration damper is a rubber compound. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Technician A only

121
Q

What do we call the location on a cam profile that is exactly opposite the toe?

A

Heel

122
Q

On a cam profile described as mostly inner base circle, the profiles between IBC and OBC are known as what?

A

Ramps

123
Q

Which of the following dimensions would be consistent with a typical engine timing gear backlash setting?a. 0.002” (0.05mm)b. 0.024” (0.60 mm)c. 0.008” (0.20 mm)d. 0.014” (0.36 mm)

A

0.008” (0.20 mm)

124
Q

In which direction must a camshaft be rotated on a diesel engine with a crankshaft that is rotated clockwise?a. Clockwiseb. Counterclockwisec. Either clockwise or counterclockwise depending on the engine

A

Either clockwise or Counterclockwise depending on the engine

125
Q

Which tool would be required to measure the cam lift of a cylinder block-mounted camshaft in position?

A

A dial indicator

126
Q

A camshaft gear is usually precisely positioned on the camshaft using what?

A

Key and Keyway

127
Q

When grinding a valve face to remove pitting, the critical specification to monitor during machining would be what?

A

Margin

128
Q

Which of the following operating conditions would be more likely to cause a valve float condition?a. Operating in the droop curveb. Engine overspeedc. Engine lug downd. Operating in the torque rise profile

A

Engine overspeed

129
Q

When grinding a new set of cylinder valve seats, which of the following should be performed before the machining?a. Install the valve guidesb. Adjust the valve yokesc. Install the rockersd. Install the valves

A

Install the valve guides

130
Q

What is the reason for using a pair of oppositely wound valve springs?

A

To minimize valve dynamic flutter

131
Q

Technician A states that the backlash in timing gearsets can be measured with a dial indicator. Technician B states that if the gear backlash is insufficient, the result can be gear whine. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Both A and B

132
Q

Technician A states that helical cut gears are often used in engine timing geartrains because they operate more quietly. Technician B states that shaft thrust loads are much higher when helical cut gears are used. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Both A and B

133
Q

Technician A states that when installing an interference-fit gear to a shaft, the gear should not be heated above 4008F. Technician B states that if an oxyacetylene rosebud is not available, an interference-fit gear should be pressed to the shaft using a hydraulic press. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Technician A only

134
Q

Technician A states that it is good practice to lubricate the inside bores of camshaft bushings to facilitate camshaft installation. Technician B states that if the cam bushing oil holes are not properly aligned, an immediate camshaft failure could be the result. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Both A and B

135
Q

Which of the following methods is used to transfer drive from the crankshaft to the camshaft on most commercial diesel engines?a. Fluid couplingb. Belt and pulleyc. Timing chain and sprocketd. Gears

A

Gears

136
Q

Technician A states that variable valve timing (VVT) is used on some diesel engines to delay the closing of intake valves on the compression stroke. Technician B states that VVT is used to open the intake valves early during the power stroke. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Technician A Only

137
Q

What type of cam geometry is required if the objective is to load the train that rides it for most of the cycle?a. Mostly IBC profileb. Mostly OBC profilec. Symmetrical OBC and IBC profiles

A

Mostly OBC profile

138
Q

Technician A states that camshaft on a two-stroke cycle engine turns through one complete rotation per complete engine revolution. Technician B states that the camshaft on a four-stroke cycle diesel engine rotates through one revolution per two engine revolutions. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Both A and B

139
Q

Technician A states that to check cam lift, the camshaft must be removed from the engine to obtain a valid reading. Technician B states that to check for a bent camshaft, the camshaft should be removed from the engine and runout tested in V-blocks. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Technician B Only

140
Q

Technician A states that valves machined with 45-degree seats breathe with higher efficiencies than those machined with 30-degree seats. Technician B states that valves machined with 30-degree seats run cooler than those machined with 45-degree seats. Who is correct?a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

A

Neither A nor B

OTC - AD Electrical and Electronic Systems (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions