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1
Q

Any technician that holds a valid journeyman’s certificate can certify commercial vehicles CVIP?

A

False

2
Q

An inspection mechanic can issue an inspection certificate and affix an inspection decal to a vehicle when…

A

The vehicle has been found to meet the standards set out in the Commercial Vehicle Inspection Manual

3
Q

If a vehicle fail to meet inspection standards , the inspection mechanic must/

A

A) refuse to issue an inspection certificate

B) notify the owner of the vehicle that it has failed inspection

4
Q

An inspection mechanic assumes a legal responsibility for the condition of a vehicle once he/she issued an inspection certificate and attaches the inspection decal.

A

True

5
Q

Inspection can only be carried out in…

A

An inspection station licensed by Alberta transportation

6
Q

List the 6 major areas of commercial vehicle that must be inspected:

A
Couplers and hitches
Suspension
Tires and wheels
Brakes
Lamps and electrical system
Body
7
Q

No disassembly is required when inspecting hydraulic brake system components

A

False. Brake drum removal is required to inspect brake components for wear and leaks

8
Q

In order to pass inspection, tire pressure must be…

A

Within specifications listed on the tire side wall

Within 10%on tire on the same axle

9
Q

A pointless hitch drawbar eye that has a weld repair meets inspection standards?

A

False.weld repairs structurally weakens the pintle hitch drawbar eye

10
Q

An S-cam type air brake is properly adjusted when

A

Pushrods travel is as short as possible without brake drag

The angle between the brake chamber push rod and slack adjuster is not less than 90*

11
Q

Corrosion is accelerated whenever two dissimilar metals are in contact

A

True

12
Q

A good knowledge of part/component names and trade term is

A

Important for good communication

13
Q

The most important persons in an equipment repair business are the

A

Customers

14
Q

The person(s) most responsible for good communication in a heavy equipment repair business is/are the

A

Owner and service manager

Service advisor and technicians

15
Q

To ensure that you receive the correct parts from suppliers , you must

A

Supply pertinent vehicle identification
Use correct part or components names
Confirm all communications

16
Q

We should treat our competitors

A

With respect

17
Q

The telephone should be treated as

A

An important business tool

18
Q

Income from a business comes from the

A

Customers

19
Q

Profit in a business

A

Is income minus purchases , salaries and expenses

20
Q

A wire rope right regular lay refers to a cable where

A

The strands are twisted to the right, but the wires in the strands are twisted in the opposite direction

21
Q

A rope that is underworld on a drum has the load line

A

On the bottom of the drum

22
Q

The first layer of wire rope that is wrapped on a drum must be straight and close together because

A

It forms the foundation for all other layers

23
Q

The friction of lubrication on a wire rope is to

A

Reduce the friction between the ropes internal components, as well as reducing friction between the rope and sheaves and drums

24
Q

The five guideline to follow for a safe working environment while jacking or blocking are safety , floor or ground stability, load to be lifted or supported, determining the lift points and determining the height the equipment needs to be raised

A

True

25
Q

A raised vehicle should not be worked under until supported by safety stands or blocking

A

True

26
Q

The pounds per square inch load on the ground can be reduced under a jack by

A

Placing a large piece of wood under the jack will spread the load over a larger area. Reducing the pounds per square inch load

27
Q

All jacks and stand used with heavy equipment have the same load capacity

A

False

28
Q

If a height adjustment pin for a jack stand has been lost , you can use a grade eight bolt to replace it

A

False

29
Q

Equipment can be raised to the height required by using jacks , ramps or hydraulic attachments

A

True

30
Q

Who is responsible for providing workers with WHMIS training?

A

The employer must provide the training

31
Q

Employers are responsible to:

A

Provide a MSDS for each controlled product used in the work place
Inform all workers about chemical hazards at the work site
Train workers about labels, MSDS and other identifiers

32
Q

Suppliers of controller products are responsible to:

A

Provide MSDS for controlled product they sell or import

33
Q

Employees are responsible to:

A

Apply workplace labels where and when required

34
Q

The key elements of WHMIS are

A

Employee education , MSDS and product labelling

35
Q

The goal of WHMIS is to

A

Protect the worker by providing information on hazardous materials

36
Q

An MSDS must be provided for each controlled product because they

A

Provide more detailed information than can be provided on a label

37
Q

The supplier label is attached to the

A

Container in witch the product is shipped

38
Q

Hat section of MSDS would include information on personal protective equipment

A

Section 7 preventatives measures

39
Q

What is an example of an engineering device used to protect workers from airborne contact with hazardous materials?

A

Ventilation system

40
Q

How do you identify a portable gasoline container that is approved for use ? It:

A

Is approved by aether one or both of the ULC or CSA

41
Q

What is the definition of occupational exposure limit(OEL) ?

A

The maximum concentration of a hazardous substance that a healthy person can be exposed to without suffering adverse health effects

42
Q

Minimum air circulation requirements for the work site are found in the:

A

Provincial and national building codes

43
Q

Before entering a confined workspace you should

A

Use a gas detector to determine whether the area contains any dangerous fumes or gases

44
Q

What type of fire extinguisher is versatile in fighting different types of fires?

A

Multi purpose dry chemical

45
Q

When should you fight a fire for personal safety reasons?

A

The fire could block your escape route

46
Q

What are the four steps of proper portable fire extinguisher use?

A

Pull pin, aim the extinguisher , squeeze the handle, sweep the extinguisher from side to side

47
Q

Witch of the following portable fire extinguisher ms should be used to fight a small fire burning in a pile of discarded oily rags

A

Classes ABC

48
Q

A class C fire involves

A

Electrical Equipment

49
Q

What part and section of the OHS code describes the membership of a joint work site health and safety committee?

A

Part 13 section 197

50
Q

What part and section of the OHS code describes the requirements and options for protective footwear

A

Part 18 section 233

51
Q

What part and section of OHS code describes the requirement for worker training about WHMIS

A

Part 29 section 397

52
Q

What are the fort said requirements for high hazard work at a close work site with 5 to 9 workers at the work site per shift?

A

1 emergency first aided, 1 standard first aide, #2 first aid kit

53
Q

What is an employer responsibility with regard to hazard assessment at the work site?

A

To develop a plan to eliminate or control any hazard identified at the work site

54
Q

How is the Workers compensation board of alberta funded?

A

100% of the funding for the WCB comes from employers in Alberta

55
Q

What are the four categories of workplace hazards?

A

Biological, chemical, ergonomic, physical

56
Q

What is an example of an engineering control for worker protection?

A

Isolation

57
Q

When is an administrative control put in place for worker protection?

A

When an engineering control cannot eliminate or control a hazard

58
Q

Who is responsible to have an emergency response plan in place at the work site?

A

Employers

59
Q

What part of the OHS code covers first aid requirements at the work site ?

A

Part 11

60
Q

What must your employer do if first aid supplies are stored in secure containers at the work side

A

Ensure that the containers are clearly marked to indicate their contents

61
Q

What number and type of first aiders must your employer ensure are present at an isolated work site with low hazard assessments rating and 65 workers at the work site per shift?

A

2 standard first aiders

62
Q

What is the duty To use personal protective equipment according to the Alberta OHS code?

A

What you and your employer must do if a hazard assessment identifies the need for the use if PPE

63
Q

Who is responsible to ensure work site emergency response plans remain up to date ?

A

The employer and the employees

64
Q

When a work site hazard assessment identifies that workers are required to wear PPE what is your employers responsibility?

A

Ensure all workers properly use and wear the required PPE

65
Q

What is an employee responsibility with regard to the use of PPE

A

To inspect your PPE prior to each use

66
Q

Industrial protective headwear must comply with what standard ?

A

CSA

67
Q

What is not an obligation your employer assumes when a hazard assessment indicates the need for PPE?

A

To post a duty to use PPE sign at all entrances to work site

68
Q

What is a characteristic of protective footwear with a yellow triangle on the outer side or tongue of the right shoe?

A

Sole puncture protection and the grade 2 protective toe ( will withstand impact up to 90 joules)

69
Q

In what situation is your employer obligated to provide you with proper PPE according to the OHS code?

A

When workers are exposed to respiratory hazard or excessive noise levels

70
Q

Witch of the following vehicles does not require yearly commercial vehicle inspection?

A

Farm vehicles

71
Q

Ferrous metals are metals that:

A

Have an iron base

72
Q

Threads for vast iron are usually a coarse tread ?

A

True

73
Q

Which of the following ha the lowest melting point?

A

Lead

74
Q

Choose the statement which best describes elasticity

A

Elasticity is the ability is a material to be stretched and still return to it’s original shape

75
Q

When steel is heated to a high temperature and cooled slowly, the metal will be:

A

In a softened state , easy to work

76
Q

Vulcanizing rubber refers to:

A

Heating raw rubber with sulphur to alter it’s properties

77
Q

What is the health hazard when working with asbestos and fibreglass?

A

Hazardous when inhaled

78
Q

Which of the items listed below would be best to form a gasket ?

A

Silicone

79
Q

Nylons are being used in industry as a replacement for metals?

A

True

80
Q

A cap screw with a thread pitch of 1/24 inch has:

A

14 threads per inch

81
Q

Thread series refers to the

A

Type of tread : UNC,UNF,UNEF, NPT

82
Q

Explain by short answer or sentence form , how tensile strength is indicated on imperial and metric fasteners

A
IMP lines indicate strength
MET numbers indicate class ex8.8 10.9
83
Q

What do the numbers 10-24 refer to in regards to machine screws?

A

10-diameter

24-treads per inch

84
Q

Lock washers are not suitable for use with which of the following screws ?

A

Aluminum

85
Q

A fastener with 6 radial marks on the head ha a tensile strength of:

A

Eight

86
Q

A fastener has resistance going into a threaded hole. This resistance to turning is called:

A

Run down forgive and must be added on to the full torque

87
Q

What is another name for a Woodruff key?

A

Half moon key

88
Q

Besides securing and driving components , what other function is performed by a helical spline?

A

A helical spline offsets end or axial thrust

89
Q

Applying a lubricant to the threads of a fastener and using a dry torque specification will:

A

Increase the clamp load compared to dry threads

90
Q

Split and roll pins should be installed with what kind of a tool?

A

Roll pin punch for the size of the pin

91
Q

Aerobic sealers are those that require air to enable them to cure

A

True

92
Q

Explain the function of a small ring

A

Installed in to a groove for a object to ride against

93
Q

If a fastener with thread locker or locktite is difficult to remove , you should :

A

Apply heat

94
Q

In an electric brake wheel assembly , witch components are similar to those used in hydraulic drum brake systems ?

A

Brake shoe, return springs an associated hardware
Brake drum friction surface provides a similar function
Backing plate and anchor assembly

95
Q

In an electric brake wheel assembly , which components are unique to the electric brake system?

A

Electromagnets , actuating lever and block assembly

Brake drum inner machines surface is special

96
Q

What is the function of the electric brake controller?

A

Used to synchronize or balance braking action of tow vehicle and trailer . Can be manually operated as well as by action of brake pedal

97
Q

In an emergency situation the electric trailer brakes will be able to provide the total braking requirements needed by truck and trailer combination

A

False, the trailer brakes will never be able to provide total braking required by the combined tow vehicle and trailer

98
Q

When you are using an ammeter to check the trailer brakes, a high amperage draw reading could indicate.

A

A short circuit in the electromagnet

99
Q

Explain the function of the auxiliary breakaway battery located on the trailer

A

When a trailer brakes free of the two vehicle the electrical connection to the truck battery is lost. The auxiliary breakaway battery provides full available battery power to the trailer brakes. Maximum braking should occur

100
Q

Provide reasons why electric brake systems may develop electrical problems between service intervals

A

Looseness of terminals and connectors over time
Road salt or water contamination and corrosion of electrical components and connections
Broken conductors and damaged trailer connectors
Corrosion at truck battery terminals and cables
Reduction of alternator output
Chafed and damaged conductors, insulation worn

101
Q

When testing an electric brake wheel assembly with a voltmeter, you notice a high voltage when the controller lever is moved very slightly. This indicates a normal

A

False, small movement should cause small voltage increase

102
Q

If you were testing the relationship between controlled level movement and wheel brake voltages, explain when
A low voltage reading would be normal
A high voltage reading would be normal
The highest voltage reading would be expected

A

Small lever movement-low voltage to brake
Large lever movement- higher voltage to brake
Full lever movement-maximum voltage to brake

103
Q

The truck brakes and the trailer brakes are synchronized by adjusting the brake controller during a series of road tests

A

True

104
Q

List two alberta governments acts, regulations or programs relating to vehicle safety

A

Motor transport act
Commercial vehicle inspection program
Commercial vehicle standards alliance

105
Q

A vehicle on which you did a brake job has been involved in an injury accident . The owner can sue your employer and you

A

True

106
Q

Asbestos is a health hazard. What can you do to protect yourself from this material?

A

Wear a breathing mask, as asbestos affects your lungs
Wash parts with water or a brake cleaning solution
Do not use compressed air to clean parts

107
Q

Injuries can occur around heavy equipment and components . How can you protect yourself from injury ?

A

Use hoists, jacks , lifting and moving equipment
Have your co-workers assist when lifting and moving large parts
Lift properly use your legs

108
Q

Flexible brake lines must not bulge or expand outward under high pressure applications

A

True

109
Q

What is meant by the term maxim diameter as it relates to brake drums?

A

This is the greatest diameter recommended by the vehicle manufacturer

110
Q

What is meant by the term minimum thickness as it relates to brake rotors ?

A

This is the thinnest the rotor can be as a recommended by the manufacturer

111
Q

What or who are your sources of information regarding a costumers vehicle brake problems?

A
The vehicle operator
A service advisor
A work order
Your own observation on a walk around 
A road test
112
Q

What two methods can you use to detect equipment problems once a costumer brings a vehicle to your shop ?

A

Vehicle walk around , look and touch

Vehicle road tests , listen and feel

113
Q

What safety precautions should you observe before working on or under a vehicle ?

A

Use recommended jacking points and an adequate capacity jack or hoist to lift the vehicle
Place on correct capacity axle stands
Use proper lifting and moving equipment

114
Q

Why would you only work on one brake assembly at a time on the same axle?

A

The assemble side is a reference for checking your work

115
Q

Drum diameter out of round and taper are three checks used to determine brake drum condition.

A

True

116
Q

A brake drum that has a crack in it can be welded and returned to service

A

False

117
Q

A new brake drum and a used brake drum can be used an the same axle?

A

Not normally unless the worm drum is within 0.010” (0.254mm) of the new drum diameter

118
Q

After machining , brake drums should be sanded with a 240 grit sandpaper . Why is it done?

A

This removes cutting grooves and creates a non directional finish so the show do not move sideways during applications

119
Q

If brake return springs are discoloured and slightly bent, they can be safely straightened and returned to service

A

False springs will fail in service or not provide proper tension

120
Q

Grease or oil on brake lining or on drum or disc friction surfaces can be whipped off with varsol and the parts will remain serviceable

A

False varsol itself is oil based and will contaminate lining and friction surfaces

121
Q

During inspection , brake rotors are measured for :

A

Parallelism
Lateral runout
Rotor thickness

122
Q

What two methods are used to mount brake linings to brake show and brake pads?

A

Bonding and riveting

123
Q

Prior to pad removal and calliper disassembly , what precaution should be taken before pushing the pistons back into the caliper bores ?

A

Remove about 1/2 the volume of brake fluid from the disk brake reservoir in the master cylinder

124
Q

Rotor thickness should be the same from one side of the vehicle to the other on the same axle

A

True

125
Q

When the caliper is unfastened from the anchor plate what safety precaution should be followed ?

A

Hang the caliper from a stable point to prevent damage to the flex hose

126
Q

Wheel bearings which are adjusted too loosely can have negative effect on braking

A

True

127
Q

Explain why wear indicators are used with disc brake pads

A

Wear indicators provide an audible and or visual warning of reduced pad lining thickness. This helps prevent rotor damage

128
Q

The diaphragm seal between the filler cover and the master cylinder body prevents outside air from contacting the brake fluid . This prevents water vapour from contaminating the brake fluid

A

True

129
Q

Aluminum master cylinders and aluminum wheel cylinders should not be honed as part of a repair process

A

True

130
Q

What fluid is suitable for use when honing a brake cylinder?

A

Brake fluid

131
Q

Grease or oil on rubber brake parts poses no problem for the parts of the system

A

False grease and oil can cause rubber parts to swell

132
Q

A force of 800N is applied to a master cylinder with an area of 8cm*2, the system pressure developed is

A

1000kpa

133
Q

A brake system develops 350psi on application.the force produced at a caliper piston with an area of 2.75 in/2

A

962.5lb

134
Q

A 0.5 cm diameter master cylinder is replaced with a 2.5cm diameter cylinder . The result is:

A

Less pressure in the system

135
Q

One of the reason DOT 5 brake fluid is not recommended for ABS systems is because it:

A

Is not hygroscopic

136
Q

The poly glycol-based brake fluid that has the most stable boiling point is :

A

Dot 4

137
Q

The hydraulic brake system converts kinetic energy to heat energy through:

A

Friction

138
Q

Brake fluid should be stored only in a sealed container because :

A

The fluid is hygroscopic

139
Q

Friction between two sliding surfaces depends on:

A

The amount of force pressing the two surfaces together
The temperature of surfaces in contact
The coefficient of friction of the materials in contact

140
Q

The principle of static friction is used in:

A

The park brake system

141
Q

Pressure in an enclosed liquid :

A

Acts with whisk force on equal areas

142
Q

The wheel cylinders and calipers convert pressure developed in the system into:

A

Mechanical force

143
Q

The force that tends to resist motion between objects in contact is called :

A

Friction

144
Q

Name three categories of power assist brake systems

A

Vacoom buster system
Air over hydraulic
Hydraulic over hydraulic

145
Q

Explain why vacuum type power brake boosters are not generally used on vehicles with a Diesel engine

A

Diesel engines do not create sufficient vacuum to effectively operate boosters

146
Q

To determine if a vacuum booster is vacuum suspended

A

The engine must be running

Vacuum must be on both sides of the power diaphragm

147
Q

Describe a quick test of a vacuum booster system to see of any boost exists at all

A

With engine key off, apply brakes several times to remove all vacuum. Apply brakes and hold foot down. Start engine and or turn key on. Vacuum source is activated and brakes pedal moves toward floorboard

148
Q

Vacuum boosters work because a difference exists between a low pressure are and a high pressure area

A

True

149
Q

Air over hydraulic booster systems are typically used when the vehicles has gasoline engine

A

False

150
Q

Air used in the air over hydraulic booster systems is:

A

Compressed air

151
Q

Water in the air supply system used with air over hydraulic booster systems does not have a negative effect on booster operation

A

False

152
Q

In the air over hydraulic brake booster system , a special hydraulic oil is used in the hydraulic system

A

False

153
Q

Hydraulic over hydraulic power brakes use fluid in two separate systems. This is described more accurately as:

A

Hydraulic fluid over brake fluid

154
Q

In the hydraulic over hydraulic system , pressure for the hydraulic systems is normally supplied by an

A

Power steering pump

155
Q

What type of fluid might be used in the brake system of a hydraulic over hydraulic brake system?

A

DOT 3DOT4DOT5 brake fluid
DOT 3 and 4 can be mixed
DOT 5 is used alone

156
Q

Valve bodies that have deep scores can be honed and reused

A

False

157
Q

The equalizer bracket is used between the hand brake cable and the cables leading to the rear wheels

A

True

158
Q

Park brakes may use a cable as an actuating device . The cable length is adjusted after all other adjustments

A

True

159
Q

A driveshaft type of parking brake may be rendered ineffective if

A

The driveshaft or a universal joint is broken
The driveshaft is disconnected or removed
One rear wheel is jacked up off the ground

160
Q

Brake drums used on medium duty trucks are usually made from the following material

A

Cast iron or centrefuse

161
Q

Disk brakes have both servo and self energizing action

A

False the rely on clamping force

162
Q

A horizontally mounted master cylinder has a primary and secondary piston. The primary piston is the first one activated by the brake pedal pushrod

A

True

163
Q

Double flares and ISO flares are two types of flares used on steel brake tubing

A

True

164
Q

Steel tubing with double flares can be used with fittings that are designated ISO flares

A

False double flares and fittings must never be interchanged with ISO flares and fittings

165
Q

To protect brake line fittings from damage the following tools should be used

A

Line flare nut wrenches

166
Q

Pressurized brake fluid moves the piston seal and the piston in a drum brake wheel cylinder

A

True

167
Q

Pressurized brakes fluid moves the piston seal and the piston in a disk brake caliper

A

False fluids move piston only

168
Q

Wheel cylinders are mounted on backing plates. Calipers are mounted on anchor plates

A

True

169
Q

After brake pedal release, caliper pistons return by piston seal movement. Wheel cylinder pistons return due to the action of of the brake shoe return springs

A

True

170
Q

List 4 functions of hydraulic oil

A

Transmit power
Lubricate
Seal
Cool

171
Q

Te term viscosity refers to an oils

A

Internal resistance to flow

172
Q

The two most common oil viscosity grading systems are :

A

Society of automotive engineers (SAE)

International standards organization (ISO)

173
Q

Viscosity index VI refers to

A

The amount that the oils viscosity changes with temperature

174
Q

Boundary lubrication refers to a condition where:

A

Minute imperfections on the surfaces of moving parts are in contact

175
Q

Define the term oxidation as it relates to hydraulic oil

A

Refers to the reaction of the hydraulic oil with oxygen in the air

176
Q

Three factors that will determine how quickly a hydraulic oil will oxidize are

A

The amount of air that the oil is exposed to
The oil temp
The chemical makeup of the oil

177
Q

The most important consideration when selecting a hydraulic oil is

A

Manufacturers specifications

178
Q

State three functions of the hydraulic reservoir

A

Holds the system oil supply
Cools the oil
Allows air and contamination to settle out of the oil

179
Q

The ideal capacity for a hydraulic tank is

A

Between 2to 3 times the pump flow rate

180
Q

Pressurized reservoirs are used in applications where

A

The pump inlet line may not otherwise be filled with oil

181
Q

What procedure must be done before you service a hydraulic system equipped with a pressurized reservoir

A

Depressurize the reservoir

182
Q

List three functions of the baffle plate in a hydraulic reservoir

A

Prevent rerun oil from flowing directly in to the pump inlet line
Provides time for air and contamination to settle out of the oil
Prevent slosh

183
Q

Contamination in a hydraulic system comes from the following three sources

A

Built in contamination
Ingreases contamination
Internally generated contamination

184
Q

The greatest amount of component wear is caused by contamination that is

A

The same size or smaller than component internal clearances

185
Q

Contamination that restricts the flow of lubricating oil to components

A

Larger than component internal clearance

186
Q

Coarse filters are called

A

Strainers

187
Q

Mesh or sieve number refers to

A

The numbers of openings per liners inch

188
Q

A filter having Beta Rating of B10=1 indicates that the filter removes

A

None of the 10qm contamination

189
Q

The filtering device most commonly used in the pump inlet line is a

A

100 mesh strainer

190
Q

The most common filter location on mobile heavy equipment hydraulic systems is

A

In series in the return line

191
Q

The most common filter location on mobile heavy equipment hydraulic systems is …

A

In series in the return line

192
Q

The pressure drop created by filter media is a result of:

A

Oil viscosity

Filter media permeability

193
Q

The function of the filter bypass valve is to:

A

Prevent damage to the filter caused by excess pressure

194
Q

Steel pipe sized by…

A

Nominal inside diameter and wall thickness

195
Q

The term that refers to the wall thickness of steel pipe is:

A

Schedule number

196
Q

One disadvantage of using steel pipe is a hydraulic conductor is that it:

A

Cannot be bent

197
Q

Steel tubing is sized by…

A

Outside diameter and wall thickness

198
Q

Te main advantage that tubing connectors offer over pipe connectors is that:

A

They do not use connectors threads to seal the connection

199
Q

State the flare angle of the following connectors :

A

Joint Industrial Council (JIC) 37*

Society of Automotive Engineers (SAE) 45*

200
Q

Split-flange connectors seal the connection by using:

A

An o-ring

201
Q

Hydraulic hose that is designated by a ,,-12” (dash 12) has an :

A

Inside diameter of 3/4 in

202
Q

Two common types of reusable hose connectors are:

A

Screw on socket type

Press on sleeve type

203
Q

Hydraulic oil coolers are usually connected in… In the system ….line

A

Series

Return

204
Q

A hydraulic pump with a displacement of 135 cm3 / rev is driven at 2000rpm. A flow meter installed in the pump outlet line indicates that the pump delivers 254L/min . What I the pump ‘s volumetric efficiency ?

A

94%

205
Q

As pump outlet pressure increases, the pump’s internal leakage decreases .

A

False

206
Q

Why I some internal leakage necessary within all hydraulic pumps?

A

Because lubricates moving pump parts

207
Q

The two factors that determine the amount of internal leakage in a pump are:

A

The pressure difference between the pump inlet and outlet ports
The amount of internal clearance within the pump

208
Q

Te most common cause of pitted erosion on the internal surfaces of the pump is :

A

Cavitation

209
Q

The hydraulic pump converts…..energy to…. Energy.

A

Mechanical

Hydraulic

210
Q

A hydraulic pump creates pressure

A

False

211
Q

The most important characteristic of a non-positive displacement pump is that…

A

Inlet and outlet ports are hydraulically connected

212
Q

Which of the following is a non-positive displacement pump?

A

Engine water pump

213
Q

The main advantage of a positive displacement pump over a non positive displacement pump is that…

A

Flow does not decrease significantly as pressure increases

214
Q

The two factors that affect pump flow rate are…

A

Pump displacement

Input shaft speed

215
Q

Pump displacement refers to …

A

The volume of liquid that a pump delivers in one revolution

216
Q

A 100cm3 /rev pump that is driven at 1500rpm produces a flow rate of:

A

150Lmin

217
Q

The term used to express the amount of power required to overcome a pump’s internal friction is

A

Mechanically efficiency

218
Q

The theoretical flow rate of a pump is 285L/min. What is the pump’s actual flow rate if the pump has a volumetric efficiency of 92%?

A

262.20L/min

219
Q

Cavitation occurs in a hydraulic pump when:

A

Inlet pressure falls too low

220
Q

Pump inlet pressure is affected by…

A

Pump inlet restriction

Pump drive speed

221
Q

The most common cause of hydraulic pump aeration is

A

Air leakage on the inlet side of the pump

222
Q

When a three stage telescopic hydraulic cylinder is operated the greatest force is generated when the:

A

First stage is extended

223
Q

Double acting hydraulic cylinders differ from single acting cylinders in that they …

A

Hydraulically extent and retract

224
Q

In it’s normal position , a normally closed pressure control valve blocks oil flow from it’s inlet port to it’s outlet port?

A

True

225
Q

The term that describes the pressure when a direct acting , normally closed pressure relief valve initially begins to open is:

A

Cracking pressure

226
Q

The term that describes the pressure relief valve is fully open is:

A

Full flow pressure

227
Q

Single acting hydraulic cylinders :

A

Hydraulic actuate in one direction

228
Q

Single acting hydraulic cylinders are returned by:

A

Some external force

229
Q

The definition of a fluid is…

A

A substance that flows

230
Q

The major difference between linguists and gasses Is that:

A

Liquids resist compression

231
Q

State Pascal’s Law .

A

Force exerted on a confined liquid is transmitted equally and undiminished in all directions, acting with equal force on equal areas and at right angles to them

232
Q

Pressure in a hydraulic system is created by:

A

Resistance to liquid flow

233
Q

Pressure losses in a hydraulic system are created by …

A

Resistance to flow that is created by system components

234
Q

Pressure is defined as …

A

Force per unit area

235
Q

As the force applied to a confined liquid increases , pressure :

A

Increases

236
Q

As the area that a force is acting on increases , pressure:

A

Decreases

237
Q

Match the following terms with their correct metric hydraulic units :
A) pressure 1) square meters(m2)
B)force. 2)kilograms(kg)
C)mass. 3)newtons(n)
D)area. 4)Newton metres(N•m)
Kilo pascals (kPa)

A

A4
B3
C2
D1

238
Q

The pressure resulting from 125kg acting on a circular area with a 25cm diameter is :

A

25kPa

239
Q

As the pressure acting on an area increases, the resulting force:

A

Increases

240
Q

An increase in the area that a given pressure acts upon causes the resulting force to :

A

Increases

241
Q

The pressure resulting from 450kg acting on a circular area with a 20cm diameter is:

A

140.37kPa

242
Q

Pressure created by the weight of a fluid is called …

A

Pressure head

243
Q

A pressure measurement that includes atmospheric pressure is:

A

An absolute pressure measurement

244
Q

List six safety precautions you must take when working on hydraulic equipment :

A

Recognize and heed safety information and instructions
Release hydraulic pressure prior to service
Do not use your hand to check pinhole leaks
Avoid pinch points
Avoid heating or cutting near pressurized hydraulic lines

245
Q

A resistance reading of infinity or out of limits(OL) indicates a:

A

Resistance higher than the meter is capable of reading

246
Q

A resistance reading of 2.4M ohms could be expressed as:

A

2 400 000 ohms

247
Q

The term impedance , as related to electrical test equipment , indicates:

A

The amount the test equipment will load the circuit

248
Q

The first step in operating a digital multi meter should be to :

A

Read manual

249
Q

A low resistance conductor that is connected in parallel with the ammeter’s digital display is called a:

A

Shunt

250
Q

When using the Ohm meter function of a digital multimeter , holding the two test leads together , a reading of … Is expected

A

0 Ohm

251
Q

When using a digital multimeter to measure amperage , what protects the meter from having too much current run through it?

A

Internal fuse

252
Q

A high impedance digital meter should be used when measuring electronic circuits to reduce the:

A

Possibility of circuit damage

In accuracy of meter readings due to meter loading

253
Q

Measuring the source voltage with no loads connected is known as measuring open circuit voltage?

A

True

254
Q

What digital multimeter automatically sets itself to the most accurate range within each function?

A

Auto ranging

255
Q

When using a digital multimeter to check… The meter is connected in parallel to the source of voltage

A

Voltage

256
Q

When using a digital multimeter to check… , the meter must be connected in series to allow all the circuits current to pass through the meter in order to obtain an accurate reading

A

Amperage

257
Q

Meters equipped with a …. Have an internal battery to power the meters electronics

A

Digital display

258
Q

Of the …. Is reversed on a digital multimeter , the digital display indicates a negative (-) sign

A

Polarity

259
Q

You should always use a … Digital meter when measuring sensitive electronic circuits

A

High impedance

260
Q

The use of …. Is recommended on any curch it’s especially those containing electronic components

A

Test light

261
Q

When using a digital multimeter to check … Never connect the meter to an energized circuit

A

Resistance

262
Q

To read positive amperage reading , the arrow on the ammeter’s…. Is always pointing towards the battery’s negative terminal

A

Inductive clamp

263
Q

The first step in the battery service is to:

A

Ensure that you are wearing safety glasses or a face shield

264
Q

Battery negative plates and positive plates with separatists between them are called a :

A

Element

265
Q

A battery :

A

Supplies power to operate the starter motor
Stabilizes the vehicle electrical system by absorbing voltage surges
Supplies power to accessories when the charging say stem cannot supply the demand

266
Q

A maintenance free battery :

A

Can be visually inspected and load tested for reuse

267
Q

Parallel connections within the battery result in :

A

Same voltage with increases current production

268
Q

The electrolyte in a lead-acid battery is made up of water and:

A

Sulphuric acid

269
Q

Each fully charged battery cell produces approximately :

A

2.1 volts

270
Q

When a battery is discharged :

A

All plates have changed to lead sulphate (PbSO4)

271
Q

Acid spills can be neutralized with a mixture of:

A

Baking soda and water

272
Q

When removing the battery from a vehicle for servicing , always remove the:

A

Negative (ground) cable first and install it last

273
Q

Before you perform a battery load test , the battery must be at least :

A

75% charged

274
Q

An open circuit voltage test is performed on a battery to determine:

A

The state of charge of the battery

275
Q

If a battery load test is performed on a 12 volt battery at room temperature , the final voltage should be :

A

Greater than 9.6 Volts

276
Q

When servicing a battery with tapered terminals , three necessary tools are :

A

Battery pliers, a terminal puller and a terminal spreader

277
Q

A fully charged battery is best stored:

A

In a cool or cold location

278
Q

If a battery is stored in a discharge condition , it:

A

Will freeze
Will become sulphated
May not recharge

279
Q

If a battery In a stored vehicle discharges over a period of three days

A

There might be a parasitic drain in the vehicle

280
Q

A battery will supply the most power when it is:

A

At room temperature

281
Q

Prior to charging a battery , it is most important that:

A

The plates are submerged in electrolyte

282
Q

The time required to recharge a battery depends upon:

A

The charger amperage output
The battery’s state of charge when charging begins
The battery’s rated capacity

283
Q

When boost charging a vehicle , the:

A

Ground cable should be connected the the boosted vehicle engine block or frame last

284
Q

The total current carrying capacity of multiple series battery groups :

A

Remain the same with the addition of every battery

285
Q

When replacing batteries in groups , you should:

A

Plan ahead

Replace with batteries of the same age , type , capacity and manufacturer

286
Q

Magnetic flux lines :

A

Cannot be insulated

287
Q

Like magnetic poles :

A

Repel

288
Q

A permeable material means that:

A

Flux lines concentrate in it

289
Q

The following listed material with lowest permeability is :

A

Aluminium

290
Q

Three characteristics of the direction of magnetic flux lines are :

A

Have direction from North to South Pole
Take the shortest path
Repel one another when they have the same direction

291
Q

A permanent magnet loses magnetic strength when:

A

Exposed to shock

292
Q

The three factors that affect the strength of an electromagnet are:

A

Number of turns of wire within the coil
Voltage applied to the coil
Type of core material

293
Q

An electromagnetic device that draws an iron core to it’s centre is called a…

A

Solenoid

294
Q

The right hand rule for conductors determines the:

A

Direction of the magnetic flux lines around the conductor

295
Q

When using the right hand rule for coils , the :

A

Thumb points to the North pole

296
Q

The magnetic principle used in electric motor operation is called … And states that…

A

Motor principle and states that current carrying conductor within a magnetic field will move to an area of the weaker magnetic field

297
Q

Voltage is generated in a conductor when a magnetic field:

A

Moves at an angle around a conductor

298
Q

The four factors that determine the amount of voltage produces in a conductor are:

A

The speed at which the magnetic lines of force are cut
The angle of intersection between the magnetic field and the conductor
The magnetic fields strength
The number of conductors moving through the magnetic field

299
Q

When current flowing in a coil of wire is stopped :

A

The air rounding magnetic field collapses

300
Q

Self induction can be stated as:

A

The process of producing voltage in a coil as the magnetic field collapses when current flow stops results in self induction

301
Q

Mutual induction occurs :

A

Between two coils or conductors

302
Q

Which of the following systems have movable electrical contacts that carry the systems current flow?

A

Electrical system

303
Q

Which of the following devices have no moving parts?

A

Solid state electronic devices

304
Q

Electrical systems can make very fast multiple decisions, remember past events and self diagnose problems

A

False , electronic systems can do these things

305
Q

In the technology of the semiconductor , the word semi means:

A

That something is half way between two limits

306
Q

In the technology of the semiconductor , the word conductor means:

A

That the material allows electric current to flow freely through the substance

307
Q

The base material for manufacture of semiconductors is most often :

A

Silicon

308
Q

An N type semiconductor is produced when a covalently bonded silicon crystal is doped with:

A

Antimony

309
Q

A P type semiconductor is produced when a covalently bonded silicone crystal is doped with :

A

Boron

310
Q

As the temperature of a wound resistance wire resistor rises, it’s resistance value:

A

Increases

311
Q

Resistors are specially constructed devices that can be used to:

A

Produce heat
Produce light
Limit current flows in electrical circuits

312
Q

Fixed value resistors can have:

A

Only one resistance value

313
Q

When a resistor’s resistance value is checked with an ohmmeter , it must be:

A

Isolated from any electrical voltage source

314
Q

A diode results when a P type semiconductor is bonded to an N type semiconductor material

A

True

315
Q

A diode is being tested in a reverse bias connection and an audible signal is heard , the diode is serviceable

A

False it means the diode is defected and cannot be used

316
Q

A diode testing function can be used to test diodes when using a DMM

A

True

317
Q

When a diode is being tested in a forward bias connection and an audible signal is heard , the diode is serviceable.

A

True

318
Q

Electronic control modules need to be protected from vibration

A

True

319
Q

Excess voltage in an electrical circuit may cause electronic device failure

A

True

320
Q

Excess current flow through electronic equipment onboard a unit of heavy equipment can be caused by improper:

A

Welding procedures
Use of a low impedance test equipment
Battery boosting procedures

321
Q

A signal that voltage value is on and the off is:

A

A digital signal

322
Q

A signal whose voltage value is constantly variable is called a:

A

Analog signal

323
Q

Signals from ON/OFF switches are

A

Digital signals

324
Q

Signals from a thermistor sensor are

A

Analog signals

325
Q

Before they can be used by the central processing unit, analog input signals must be processed in the

A

ADC

326
Q

All of the components in an ECM are kept at the same pace by the:

A

Internal clock

327
Q

The device that prepares the output data in a form that can be used outside the ECM is called the:

A

DAC

328
Q

A combination of eight binary code bits is called

A

A binary word

329
Q

Input data ca be stored in the

A

RAM

330
Q

Which type of RAM is connected directly to the battery rather than powered through the ignition switch?

A

Volatile

Keep alive

331
Q

The brain of the ECM is called a :

A

Microprocessor

332
Q

What part of the ECM receives information from the systems inputs?

A

Microprocessor

333
Q

What kind of memory is used for peahens storage of data?

A

PROM and ROM

334
Q

Random access memory is

A

Volatile

Nonvolatile

335
Q

Which type of memory can you take out of the ECM to write new program information to it?

A

PROM

336
Q

Which type of voltage sensor uses a predetermined voltage signal that is sent from the ECM?

A

Reference voltage sensor

337
Q

Which type of voltage sensor produces it’s own voltage signal?

A

Voltage generating sensor

338
Q

The output actuators of electronically controlled systems are :

A

Electrical motors
Solenoids
Relays

339
Q

On board fault codes can be read directly from the ECM through :

A

Blinking lights

340
Q

Off board diagnostics are accessed through the use of

A

Scanning tools
Data link connectors
Scanning tool programs

341
Q

When measuring sensitive electronic circuits , you can prevent meter loading from damaging circuits damage , causing inaccurate readings and producing high current flow through sensitive electronic components by using:

A

High impedance digital meters

342
Q

A break in the normal path of an electric circuit causes a

A

Open circuit

343
Q

The amount of current in a circuit is determined by:

A

Source voltage

Resistance of the circuit

344
Q

If an open occurs in a circuit , current:

A

Decreases

345
Q

As applied voltage increases

A

Current increases

346
Q

Voltage is :

A

Potential difference

347
Q

Resistance is:

A

Determined by circuits construction

348
Q

Amperage is :

A

Measurement of current flow

349
Q

Resistance of a circuit decreases is a

A

Short occurs in a parallel or series circuit

350
Q

As resistance of a circuit increases

A

Voltage decreases

351
Q

If a resistor in a circuit is shorted , an ammeter in the circuit would indicate :

A

More current than normal

352
Q

In heavy equipment ‘s electrical system, a resistor could be:

A

A light bulb
A two way radio
A starter motor

353
Q

Reduced current flow in a series circuit can be caused by:

A

Corroded terminals on the battery

354
Q

An element consists of

A

One kind of atom

355
Q

Electrons have a

A

Negative charge

356
Q

The nucleus of an atom has

A

Protons and neutrons

357
Q

A conductor of electricity is a material that

A

Allows electrons to move through it

358
Q

Atom consists of three still smaller particles called

A

Proton
Electron
Neutron

359
Q

Of these three particles , the positively charged particles is the …
The negative charges particles is the…
The particles found in the nucleus of the Atom are the …

A

Proton
Electron
Proton and neutron

360
Q

An atom that has gained a surplus of electrons is said to be a … ion and if the atom has lost a number of electrons, it is called a …ion

A

Negative charged

Positive charged

361
Q

The electrons found in the outermost orbit of the atom are known as

A

Valence electrons

362
Q

Most insulators are

A

Compound of two or more elements

363
Q

Voltage is electrical

A

Force

364
Q

The opposition to electron flow is:

A

Resistance

365
Q

Resistance of a conductor is determined by :

A

Length , cross-sectional area, temperature and type of material

366
Q

Current is electrical

A

Flow

367
Q

Which of the following forms of voltage sources require polarity markings?

A

Direct voltage

368
Q

Technicians should wear static straps when working on any electronic components to prevent discharges of damaging voltages that are produced by

A

Friction

369
Q

List two advantages when braking a vehicle equipped with antilock brakes

A

Directional stability control

Decrease stopping distances

370
Q

Braking is most effective when the rotation of the wheel an tire is slowed

A

Without overcoming friction between the tire and the road

371
Q

The antilock air brake system modulates … To slow the vehicle effectively and under control

A

Brake application pressure

372
Q

Antilock brake systems can modulate the brake application pressure up to… times per second

A

100

373
Q

List the basic components of an antilock system

A
Tone wheel
Speed sensor
ECU
ABS lamp indicator
Brake modulation valve
374
Q

A modulator valve is in the air lines to each front wheel an to right driving tandems and the left driving tandems. What type of ABS system is this?

A

4S4M

375
Q

The purpose of the tone ring is to

A

Induce electrical pulses in the speed sensor

376
Q

The antilock systems ECU is a computer that:

A

Analyzes and processes speed sensor signals

Controls the brake modulator valves

377
Q

A vehicle is being driven with ABS indicator light illuminated . This indicates to the driver that

A

There is an antilock system malfunction

378
Q

If the antilock system fails during vehicle operation, the standard brake system will

A

Function normally

379
Q

The tone rings are most commonly mounted to the

A

Wheel hubs

380
Q

In tandem drive axle truck chassis with one modulator valve for each side , the modulator valve controls

A

Two brake chambers

381
Q

Of arc welding must be performed on a vehicle with antilock , the ECU should be

A

Unplugged or disconnected

382
Q

When removing the hub assembly from an antilock equipped vehicle , a technician must

A

Take care not to damage the tone ring and sensor

Support and block the vehicle safely

383
Q

A wheel speed sensor is positioned by

A

Pushing the sensor in until it touches the tone wheel

384
Q

Most antilock systems specify that all tire sizes must be kept within … Circumference of each other

A

3/4”

385
Q

Spring brake chambers apply and him a parking brake application

A

Without air pressure

386
Q

Caution must be exercised when working around spring brake equipped vehicles because

A

Spring brakes contain large, powerful springs

387
Q

Air supply for parking/emergency brake operation flows through a double check valve so that the emergency brake will

A

Not apply of either service reservoir air pressure lost

388
Q

The function of the park control valve is to provide manual

A

And automatic control of all the parking /emergency brakes on the unit

389
Q

A quick release valve is often used in parking /emergency brake circuits to provide quick

A

Application of the spring brakes

390
Q

An anti-compounding double check valve is often used in parking / emergency brake circuits to

A

Release the parking / emergency brakes when the service brakes are applied

391
Q

Some truck / tractor units are equipped with a spring brake valve that

A

Allows the spring brakes to modulate application if primary service reservoir air pressure is lost

392
Q

A relay valve is used in parking/emergency brakes circuits that use spring brake valves to ensure that the spring brakes

A

Apply and release quickly

393
Q

The purpose of the trailer service line is to transmit air pressure

A

To apply and release trailer service brakes

394
Q

The purpose of the trailer supply line is to transmit air pressure

A

To charge the trailer reservoirs

395
Q

The trailer supply valve supplies air pressure to the trailer from

A

Both primary and secondary reservoirs

396
Q

In the event that pressure in both primary and secondary reservoirs falls bellow 50 Psi (345 kPa) the

A

Trailer supply valve will close off supply air pressure to the trailer
Trailer emergency brakes will apply
Tractor protection valve will close the trailer service line

397
Q

The purpose of the trailer brake control valve is to allow the operator to

A

Independently control trailer service brakes

398
Q

If the operator makes a 20 psi (138kpa) application with trailer brake control valve while making a 10 psi (69kpa) application with the dual-circuit brake valve

A

Tractor brakes will be applied with 10 psi and trailer brakes applied with 20psi

399
Q

Tractor equipped with a bobtail pro portioning relay valve will reduce

A

Primary application pressure when tractor is not towing a trailer

400
Q

The brake light switch is a normally

A

Open switch that is closed by primary or secondary service pressure

401
Q

List nine safety precautions that must be observed when working around air brake equipped vehicles

A

Park vehicle on a level surface with wheels blocked
Always wear safety glasses
Exercise are when working around a running engine
Drain air from the system prior to service
Never adjust system pressure above manufacturer specifications
Use caution when working around spring brakes
Understand the air brake system you are working on
Avoid inhaling dust from brake linings

402
Q

When visually inspecting the compressor mounting security look for

A

Cracked or damaged mounting brackets

Loose missing fasteners

403
Q

A properly adjusted compressor drive belt will have a maximum deflection of

A

1/2 to 3/4 inch

404
Q

Of you discover excessive oil when draining the air reservoirs, the problem is likely

A

Worn air compressor piston rings and cylinders

405
Q

CVIP specifications state that a vehicle could be put out of service of the brakes chamber pushrod travel does not fall between

A

3/4 to 1 1/2 inch

406
Q

When performing the air brake system governor cut-off , pressure warning and pressure buildup test, you found that the low-pressure warning device went off at 70psi. This means that the operation of the device is

A

Acceptable

407
Q

The Alberta CVIP states that the vehicle compressor should build up from …. To … Within 3 minutes

A

50psi to 90psi

408
Q

You are testing a vehicle with a governor cut-out pressure of 120psi a find that the governor cut-in pressure is 90 psi . The problem is

A

Faulty governor

409
Q

You are checking for supply circuit leakage in a tandem gravel truck that is towing a pup trailer . The primary service reservoir pressure drops 4 psi and the secondary reservoir drops 10 psi over 2 min period. You conclude that

A

Primary leakage is acceptable but secondary leakage is excessive

410
Q

A body-loaded truck showed a pressure drop of 6 psi in the primary reservoir and 2 psi in the secondary reservoir when the service delivery circuit was tested for leakage . You conclude that

A

Primary leakage is excessive but secondary leakage is acceptable

411
Q

Pushrod travel for a properly adjusted cam-operated foundation brake should be

A

As short as possible without drag between the brake linings and drum

412
Q

The angle formed between the brake chamber pushrod and the slack adjuster arm when the brakes are applied should be

A

Never less than 90*

413
Q

When performing an automatic emergency brake circuit test, you found that the primary air reservoir pressure dropped when secondary air reservoir was drained. The most probable cause of this fault would be a leak in the

A

Check valve in the primary reservoir

414
Q

Dented or kinked air lines in the parking/emergency brake circuit could cause the springs to

A

Be sluggish when applied and released

415
Q

Opening the supply line of a fully charged tractor/trailer combination with the parking brakes released should cause
The trailer spring brakes to
The trailer supply valve to

A

Immediately apply

Shut off air to the supply line between 60psi and 20 psi

416
Q

Before you attempt to mechanically cage spring brakes , you should

A

Inspect the spring brake chamber for damage

417
Q

Before you back off the brake on units that have automatic slack adjusters , you must be sure to

A

Remove or disengage the adjustment pawl

418
Q

Alberta CVIP states that a vehicle will fail inspection if the radial clearance between the camshaft and bushings is

A

0.085inch

419
Q

Removing material from the inside diameter of a brake drum results in

A

Reduce strength

Reduced ability to dissipate heat

420
Q

Camshaft axial play should not exceed

A

0.030 inch

421
Q

Alberta CVIP states that an air-brake equipped vehicle will be put out of service if the brake linings are worn below

A

5/16 inch

422
Q

Camshaft axial play is adjusted by

A

Adding or removing shims between the slack adjuster and it’s retaining snap ring

423
Q

If the angle between the brake chamber pushrod and slack adjuster arm is incorrect , you must:

A

Adjust the brake chamber clevis

424
Q

It is important to closely watch brake adjustment following a brake reline because

A

Brake chamber pushrod travel will increase more rapidly than normal as the brake lining wear in to the brake drums

425
Q

Friction

A

Refers to the resistance between two moving bodies

426
Q

In order to stop a moving vehicle , the braking system must convert moving vehicle energy into

A

Heat energy

427
Q

A vehicle requires 200hp to accelerate from 0 to 100km/h in 60 seconds . If the same vehicle is brought to a complete stop in 6 sec, the braking system must develop

A

2000hp

428
Q

Of the weight of a vehicle is doubled , the power requires to stop the vehicle will

A

BE increased 4 times

429
Q

If both speed and weight of moving vehicles are doubled , the power required to stop the vehicle will

A

Be increased to 8 times

430
Q

One advantage that air brake systems have is that

A

The system does not have to bled when connecting or disconnecting trailers like hydraulic braking systems do

431
Q

One disadvantage air brake systems have is that

A

There is always some brake lag

432
Q

When a given volume of air is compressed to 1/2 it’s original volume , it’s pressure will

A

Double

433
Q

When a give volume of air is compressed to 1/2 it’s original vole , theoretically it’s temp will

A

Double

434
Q

A driver makes a 40 psi air brake application. If the vehicle is equipped with brake chambers that are 30in2 in area , each brake chamber will generate

A

1200lb of force

435
Q

If the brake chamber in a truck and a driver makes 40psi air brake polo cation. If the vehicle is equipped with bake chambers are 30in2 in area, each brake chamber will generate 1200lb of force was acting on a 6 in slack adjuster , the brake shaft would feel:

A

7200in lb of torque

436
Q

The term lag time refers to the time required

A

For the air system to apply the brakes

437
Q

The component of the basic air brake system that connects the air system to the foundation brakes is the

A

Brake chamber

438
Q

The component of the basic air brake system that allows the operator to regulate brake application pressure is the

A

Brake valve

439
Q

The function of the governor is to

A

Limit maximum air system pressure

440
Q

The slack adjusters

A

Convert linear motion to rotary motion
Multiply the braking force from the brake chamber
Provide a place for brake adjustment

441
Q

Connecting lines and fittings are important to air brake system operation because they affect

A

The speed of air flow through the system

442
Q

When an air brake compressor piston is in it’s compression stroke , the inlet valve

A

Is closed and the discharge valve is open

443
Q

When the compressor is in it’s unloaded cycle

A

The inlet valves are held open

444
Q

The governor controls maximum air system pressure by

A

Putting the compressor in the unloaded cycle

445
Q

The automatic drain valve drains moisture and contamination from the reservoir when

A

Any drop in reservoir pressure

446
Q

Air brake antifreeze is used in the air brake system to

A

Prevent moisture in the system from freezing

447
Q

Desiccant type air dryers rely on

A

Beads that absorb moisture vapour from the air stream

448
Q

Single check valves are installed in the inlet line to both the primary and the secondary service reservoirs because they

A

Prevent air loss in the event of a failure in the other reservoirs

449
Q

The function of the safety valve is to

A

Limit air pressure buildup in the event of a governor failure

450
Q

CMVSS121 states the minimum pressure at which the low pressure warning devices must warn the operator is

A

60psi

451
Q

Nylon air brakes tubing should not be used where it may be exposed to

A

Hight temp
Abrasive and wear
Excessive movement

452
Q

In the released position , the inlet/exhaust valves of the dual-circuit brake valve are in the following condition

A

Inlet are closed and the exhaust are open

453
Q

The dual -circuit brake valve holds it’s inlet and exhaust valve closed

A

When the valve is in it’s balanced position

454
Q

The function of the relay valve in the primary brake circuit is to speed up the

A

Application and release of the primary service brakes

455
Q

When the dual circuit brake valve delivers 20 psi of primary service application pressure , a relay valve with cracking pressure of 2.5psi reacts by sending

A

17.5 psi to the primary brake chamber

456
Q

A type 24 brake chamber has an

A

Area of 24in2

457
Q

During normal brake applications, the secondary section of the dual circuit brake valve is applied by

A

Primary service air pressure

458
Q

The function of the quick release valve in the secondary brake circuit is to

A

Speed up the release of the secondary service brakes

459
Q

Properly adjusted cam operated foundation brakes

A

Keep the brake linings as close to the brake drum as possible without dragging when the brakes are released

460
Q

When a cam operated foundation brake is in the released position , the brake shoe rollers are

A

In contact with the low cam area

461
Q

The linear motion of the brake chamber pushrod is converted to twisting force at the brake camshaft by the

A

Slack adjuster

462
Q

Brake drums must be able to

A

Provide an acceptable braking surface
Withstand hight temp
Resist distortion

463
Q

Brake drum thickness

A

Affects the drums ability to dissipate heat

464
Q

Cam operated foundation brakes are called

A

Non servo brakes

465
Q

The term brake fade occurs at excessively high brake temp because the

A

Brake lining coefficient of friction is reduced

466
Q

Brake lining edge code identifies the lining by

A

The initials of the manufacturer
The normal coefficient of friction
The hot coefficient of friction

467
Q

Using brake lining with a GAWR that is too low can result in

A

Brake fade

468
Q

During braking, the brake spider transfers torque from the

A

Brake shoe to the axle housing

469
Q

Flat brake cams are often used in steer axle foundation brakes because they

A

Have a slower rate of application than S-cams

470
Q

The foundation brake component that provides a place to adjust brake lining to drum clearance is the

A

Slack adjuster

471
Q

During application , the angle formed between the brake chamber pushrod and the slack adjuster arm should NEVER be

A

Less than 90*

472
Q

One of the most frequent causes of brake failure is

A

Improper brake adjustment

473
Q

The automatic slack adjuster automatically makes a brake adjustment when

A

The brakes are released

474
Q

The advantage that air disc brake configuration provide over cam operated drum brake configuration is that they

A

Are not prone to brake fade

475
Q

The caliper of an air disc brake must be able to slide on it’s mounting pins so that the

A

Outboard brake pad contacts the brake rotor

476
Q

The most significant difference tween a pre-CMVSS 121 trailer and a CMVSS 121 trailer is that:

A

Pre-CMVSS 121 trailers are equipped with air-applied parking and emergency brakes

477
Q

The function of the trailer service line is to

A

Carry service air pressure from tractor to the trailer

478
Q

One of the functions of the trailer supply line is to

A

Carry supply air to charge the trailer reservoirs

479
Q

The one-way check valve in the relay emergency valve on a pre-CMVSS 121 trailer prevents

A

Trailer reservoir pressure from falling I air pressure falls in the trailer supply line

480
Q

One way of releasing the brakes after an emergency brake application on a pre-CMVSS 121 trailer is to

A

Drain the trailer air reservoir

481
Q

One safety precaution you must observe when parking a pre-CMVSS 121 trailer is

A

The trailer wheels must be blocked

482
Q

Loss of air pressure in trailer supply line on a CMVSS 121 trailer results in

A

Applying the trailer spring brakes

483
Q

When charging a CMVSS121 trailer equipped with SR 5 trailer spring brake control valve, the trailer :

A

Spring brakes release before the trailer air reservoirs are charged

484
Q

In order for a towing trailer to be towed as a single unit , the

A

Shut off valves in the service and supply lines must be closed

485
Q

The component on a towing trailer that vents the supply line to the towed trailer is

A

The quick release valve

486
Q

The term cracking pressure refers to the

A

Pressure required to overcome internal friction in an air brake valve

487
Q

The advantage of a pilot relay valve over a standard relay valve is that it

A

Has no difference between incoming signal pressure am delivery pressure

488
Q

The delivery pressure from the pilot relay valve on a towing trailer is sent to the

A

Service line to the towed trailer and the service relay valve

489
Q

The purpose of the spring acting on the upper surface of the pilot relay valve is to

A

Reduce the time required to apply the trailer brakes

490
Q

The function of the pressure protection valve installed in the supply line to the converter dolly air reservoir is to

A

Ensure that dolly parking/emergency brakes release before the dolly reservoir is charged

491
Q

The one way check valve in the pressure protection valve on a converter dolly prevents

A

Reservoir air pressure from falling if dolly supply line pressure is lost

492
Q

The trailer release valve is installed on a converter dolly to

A

Ensure that air pressure is allowed to build up in the towing trailer and converter dolly before it flows to the following trailer
Prevents tractor supply circuit pressure from falling too low when trailers and dollies are charged
Keep the operator from manually holding the trailer supply valve in for a long period while the trailers am dollies are charged

493
Q

The pilot relay valve on the converter dolly relays

A

Service air pressure to the relay emergency valve on the dolly and the service line to the following trailer

494
Q

Hammer are selected for size by the

A

Weight Of the head

495
Q

The screwdriver blade that has an hourglass shape is the

A

Clutch and is sized by diameter of the blade or tip

496
Q

The punch recommended for removing or installing split or roll pins is the

A

Roll pin punch

497
Q

Describe how a prick punch or centre punch is selected for it’s size

A

Sized by diameter of the stock

498
Q

The chisel that may be beat suited to clean up square keyways is a

A

Cape chisel

499
Q

What is the general cutting edge angle of a flat chisel?

A

60* to 70*

500
Q

Open end wrenches are designed to fit a bolt head

A

Across the flats of the head

501
Q

Name the wrench beat suited for loosening or tightening nuts on steel lines

A

A flare nut or line wrench

502
Q

Dowel removers work well with dowels that are broken off at the work surface

A

False ,a portion of the dowel must be above the work surface

503
Q

A bearing separator is also referred to as a bearing splitter and is used to remove the balls of a bearing from within the race area

A

False , a split puller is used to Accra bearings on a shaft

504
Q

When using a hacksaw , the recommended number Of teeth that should be on the material is

A

No less than two

505
Q

The direction the teeth on an adjustable frame hacksaw blade should face when mounts in an adjustable frame is

A

Forward

506
Q

The small pieces of material or pins that lodge in the teeth of a file can be removed easily with a tool referred to as a

A

Scorer

507
Q

What distinguishes a safe edge file?

A

Has no teeth on the edge

508
Q

List four angles of importance and the amounts of each, on the sharpened portion of a drill bit

A

Cutting edge or point angle 59*
Included angle is 118*
Lip clearance angle is 12* to 15*
Dead centre angle is 120* to130*

509
Q

The direction reamers must be rotated when going into the hole and coming back out of the hole are

A

Going in clockwise

Coming out clockwise

510
Q

List three standard threads taps in the order they should be used

A

Taper
Plug
Bottoming

511
Q

The tap best suited to tap a tapered hole for sealing of pressure would be a

A

National Pipe Thread (NPT) tap

512
Q

When performing a double flare on a piece of tubing :

A

Install the tubing so it protrudes the height of the shoulder of the adapter

513
Q

How should the rest of a floor or bench grinder be positioned

A

As close to the stone as possible

514
Q

The speed of a certain grinder is 3450rpm. Te wheel you wish to install reads 3600rpm. It is safe to install the wheel on the grinder ?

A

True

515
Q

When installing a heli-coil in a hole , the tap in the kit :

A

Is a special tap for each particular coil

516
Q

A carbon steel drill bit should be rotated at what speed compares to a high-speed steel drill bit ?

A

One half the speed of high-speed steel

517
Q

What is the purpose of the paper on the side of grinding stone ?

A

Protects the stone , contains information about the stone size and speed

518
Q

Combination pliers must be used to remove spring hose clamps

A

False

519
Q

Googles are worn when using oxyacetylene equipment to protect the eyes from

A

Light
Heat
Sparks and slag

520
Q

Technician A says it is acceptable to carry a disposable lighter in your pocket when using oxyacetylene equipment . Technician B says nylon clothing is much better to wear than cotton when using oxyacetylene equipment . Which technician is correct ?

A

Neither technicians

521
Q

To check for leaks in oxyacetylene equipment , you should use

A

Approved leak detection solution

522
Q

Of grease is exposed to pure oxygen , the grease can explode :

A

Whit out ignition

523
Q

When using oxygen from a cylinder , you should open the valve :

A

Fully

524
Q

Fusible plugs in acetylene cylinders are located

A

In the too , bottom and neck of the cylinder

In the valve of the cylinder

525
Q

Acetylene should only be drawn from an acetylene cylinder when the cylinder is

A

Upright

526
Q

The specific gravity for propane vapour is

A

1.55

527
Q

When liquid propane is released to the atmosphere , it

A

Changes to vapour and accumulates in low areas

528
Q

The colour of an oxygen hose used with oxyacetylene equipment is

A

Green

529
Q

The colour of an acetylene hose with oxyacetylene equipment is

A

Red

530
Q

Check valves used with oxyacetylene equipment are installed in

A

The oxygen hose

The acetylene hose

531
Q

When you are finished using oxyacetylene equipment , the oxygen an acetylene should be shut off at the

A

Cylinders , pressures bled off and the regulators should be backed out to the free position

532
Q

The most suitable flame to use when heating with oxyacetylene equipment is

A

A neutral flame

533
Q

When you purge oxyacetylene equipment prior to lighting the torch , you adjust the acetylene regulator to

A

5 psi

534
Q

Of a backfire occurs when using an oxyacetylene hearing tip , it may be caused by

A

Both gases set too low

535
Q

The material that can be easily cut using an oxyacetylene touch with a cutting attachment is

A

Carbon steel

536
Q

When an oxyacetylene torch is used for cutting , the torch is

A

Inclined more for thin material

537
Q

What standards must a full body harness meet if manufactured on or after July 1 2009?

A

CSA

538
Q

How often must your inspect your fall arrest equipment ?

A

Before use on each shift

539
Q

What is the minimum distance a ladder must protrude above the intended landing point?

A

1m (3ft)

540
Q

What is the safety factor for scaffold systems ?

A

Four times the load that may be imposed on it

541
Q

At what height must an employer have a guardrail erected for a temporary work area?

A

3m (10ft)

542
Q

When conducting a hazard assessment relates to lifting and handling a load, your employer must consider the

A

Weight , size and shape of the load

543
Q

What is not an example of a recorded lifting technique ?

A

Lift no higher than eye level

544
Q

What is the goal of proper lifting technique ?

A

To eliminate loading stresses on the soft tissue of your lower back

545
Q

How is safe working load (SWL) defined ?

A

Breaking strength divided by the safety factor

546
Q

What does the term shock loading mean when applied to rigging equipment ?

A

The along is exposed to stress by having the load suddenly started or sroppedb

547
Q

What rigging factor of safety is to be used when lifting and transporting workers?

A

10:1

548
Q

How often must rigging be inspected ?

A

At the beginning of each work shift

549
Q

What is recommended when attaching the hook to an eyebolt ?

A

Always use a shackle when attaching the hook to a load

550
Q

What is the recommended sling angle when rigging a load ?

A

The sling angle must never be less than 60*

551
Q

Which of the following is not a method of protecting a conductor from corrosion ?

A

Flux

552
Q

There is a discussion between two technicians about wiring harness and terminal repairs. Technician A thinks that rosin paste and rosin core solder would work best for electrical repairs. Technician B thinks that when a conductor needs to be replaced, it should never be replaced with a smaller gauge wire . Who is right?

A

Both A and B technicians

553
Q

All wiring harness connectors have:

A

Locking mechanism
Mating guides
Removable pins and sockets

554
Q

The purpose of a ….. …… Is to pass electrical current from one set of wires to another .

A

Conductor connector

555
Q

….. ….. must are the large current flows required to start a high compression Diesel engine

A

Cranking circuits

556
Q

…….. ……. on heavy equipment is used to transfer visual, audio or digital information

A

Communication wiring

557
Q

To open a wiring harness that is taped , a ……. ……. can be used without damaging the conductor.

A

Seam ripper

558
Q

Always install hold-down brackets, clamps and wire ties to prevent wiring harness vibration or movement that could cause ….

A

Chafing

559
Q

If conductor wires are not damaged , but the conductor insulation is damaged , it can be repaired by using …. ….. …..

A

Heat shrink tubing

560
Q

An approved method of repairing copper conductors is ….. ……

A

Crimp splicing

561
Q

All electrical schematics are drawn in a …… condition

A

De-energized

562
Q

The components of an electrical switch that conducts the electrical current are called ……

A

Contacts

563
Q

In a trailer clearance light circuit, the non-cycling circuit breaker keeps overrating and has to be manually reset. Technician A says that installing a cycling circuit breaker with higher amperage than specification will correct the problem. Technician B says installing a higher amperage cycling circuit breaker may cause damage to the wiring harness and components . Who is right ?

A

Technician B

564
Q

A new set of conductors must be connected to screw-secure trailer plug terminals . Technician A says that the conductor wires ends must be tinned with solder before they are inserted . Technician B says that before the plug is put into service , the conductor wires and screw -secured-connectors should be covered with dielectric grease to prevent corrosion . Who is right?

A

Technician A and B

565
Q

When a fuse in an electrical lighting circuit overheats and burns out quickly , the probable cause is :

A

A ground fault

566
Q

When two or more electrical lighting circuits operate abnormally at the same time , the probable cause is

A

A short

567
Q

When one lamp in an electrical lighting circuit burns dimly when compared to the other Lamps in the same circuit the probable cause is:

A

An unwanted high resistance

568
Q

When current stops flowing in part of an electrical lighting circuit , the probable cause is :

A

An open circuit

569
Q

When testing a relay a cross the coil you receive a reading of OL what is the most likely cause of failure?

A

An open circuit

570
Q

What are the four factors a technician must consider when repairing broken conductors or replacing damaged conductors ?

A

Mechanical Strength- connections must be physically strong
Electrical Integrity - conductor repair must allow required current flow
Insulation- the repair must insulate the conductor to prevent corrosion or short circuits
Security- the repair must be secure to prevent chaffing and vibration damage

571
Q

The number of millimetres in one centimetre is

A

Ten

572
Q

The term witch beat describes the tendency of a body to remain in motion is

A

Inertia

573
Q

Force may be best described as a

A

Push or pull

574
Q

Area of a circle is calculated by multiplying the

A

Constant 0.7854 by the radius square

575
Q

Convert 21/64 to a decimal rounded to three decal places

A

0.328

576
Q

Convert 0.484375 to an exact fraction

A

31/64

577
Q

Convert 0.280 to a practical fraction to the nearest 1/32

A

9/32

578
Q

Calipers can be used to measure

A

Inside or outside diameters

579
Q

A stepped feeler gauge for measuring a clear emcee of 0.015 inch will be marked on the blade

A

0.014 inch to 0.016

580
Q

A typical telescoping gauge set has a typical range of

A

5/16 inch to 6 inches

581
Q

A standard 0-1 inch outside imperial micrometer shows 3 large division, 3 small division and 3 on the thimble . The amount being measured is

A

0.378 inch

582
Q

A standard outside imperial micrometer measures 5.671 inch . The divisions showing on the scale would be

A

6 large 2 small and 21 on the thimble

583
Q

An inside micrometer with 2 late divisions , 3 small divisions and 15 on the thimble is measuring :

A

2.290 inch

584
Q

An inside imperial micrometer measuring 4.678 inch will have which of the following scale readings showing ?

A

1 large 3 small 3 on the thimble

585
Q

A 0 to 1 inch vernier outside imperial micrometer is showing 8 large divisions, 3 small divisions 22 on the thimble and 6 on the vernier scale. The micrometer is

A

0.8976 inch

586
Q

A depth micrometer will measure protrusion accurately

A

False ,erasures a recession

587
Q

A dial indicator plunger should be set to move

A

At mid range of travel

588
Q

Precision measuring tools should be stored

A

In a special drawer or cabinet

589
Q

Torque wrenches measure

A

Rotation force

590
Q

If a force of 220N was applied on a wrench which is 600 mm long , the resulting torque would be

A

132N • m

591
Q

To torque a head bolt to 100 lb-ft using a torque wrench 2 feet long , you would have to pull on the wrench with … lb of force

A

50

592
Q

List three functions of a vehicle frame

A

Provide a platform on which the major vehicle components are attached
Support the load that the vehicle is intended to carry
Resist shock an torsion loads when the vehicle is in operation

593
Q

The point at which the maximum force is concentrated on a frame is called the

A

Maximum bending moment

594
Q

A ladder type frame is made up of

A

Crossmembers

Parallel frame rails

595
Q

The function of frame crossmembers is to

A

Provide strength and rigidity to the frame assembly

596
Q

Which one of the following is not a common frame rail shape

A

Trapezoid

597
Q

The surface between the flanges of an I-beam frame rail is called the

A

Web

598
Q

What is the function of a gusset that is attached to a frame crossmember ?

A

Provide resistance to the frame weaving

599
Q

The size and shape of the frame components affect the strength of the frame ?

A

True

600
Q

Define the term yield strength as it applies to the strength of frame materials

A

The amount of stress that the material can withstand before becoming permanently deformed

601
Q

Which of the following frame materials should have the highest yield strength?

A

Heat treated alloy steel

602
Q

The term section modulus refers to the strength of frame components based on

A

Height
Width
Thickness
Shape

603
Q

A frame with a high resisting bending moment RBM has less strength than a frame with low RBM

A

False , the greater the RBM the greater the strength of the frame

604
Q

List four functions of a vehicle suspension system

A

Secure the axle to the frame while maintaining proper alignment
Support the weight of the vehicle and is cargo while maintaining lateral stability
Cushion shock loads
Allow axle movement so that the tires follow the contour of the road

605
Q

The term unsprung weight refers to the weight of the vehicle and it’s load

A

False , the combined weight of the components below the connection point is called unsprung weight because it is located below the suspension system

606
Q

The suspension system must hold the axles in alignment with the frame . This means that the:

A

Wheels are held parallel to the frame rails

607
Q

Three of the most common types of energy-absorbing devices used in suspension systems are

A

Leaf springs
Rubber Cushing
Air springs

608
Q

The energy-absorbing device of a is pension system is released when it rebounds .

A

True

609
Q

Solid mount suspension systems are beat suited to applications that:

A

Operate on rugged terrain

610
Q

Equalizer beams reduce the effect of chick loads to the vehicle frame by

A

50%

611
Q

Axles are stabilized against braking and acceleration force by ….

A

Longitudinal torque rods

612
Q

The function of transverse torque rods is to ….

A

Provide improved side to side stability by distributing side loads more evenly across the entire length of the axle

613
Q

Progressive lead springs provide a low spring rate when the vehicle is unloaded and a high spring rate under load

A

True

614
Q

Auxiliary springs help to support the vehicle when it is

A

Loaded

615
Q

Spring shackles accommodate changes in the spring length as the suspension jounces and rebounds

A

True

616
Q

The main function of a shock absorber is to….

A

Dampen spring oscillation

617
Q

The function of vertical drive pins on a rubber cushion type suspension is to…..

A

Allow the saddles to move up and down as the load cushions deflects , thus maintaining alignment of the saddles with the frame rails

618
Q

An advantage that air spring suspensions have over other suspension types is that they provide superior

A

Ride quality

619
Q

State the function of the pressure protection valve in an air spring suspension

A

Ensures that a minimum safe pressure is maintained in the air reservoir for air brakes operation if a leak occurs in the suspension air system

620
Q

The ride height control valve supplies air to the air spring when:

A

Additional load is added to the vehicle

621
Q

The function p the two way control valve and dump valves is to

A

Allow the driver to exhaust the air springs so that the suspension will lower when connecting or disconnecting a trailer

622
Q

All bearings are designated to provide support to moving parts , keep parts in alignment , increase friction an provide a replaceable wear surface

A

False , bearings are designed to decrease friction

623
Q

Axial loads may be offset by

A

Needle bearings

624
Q

Crush is a term used to describe the

A

Force on a preloaded bearing

625
Q

Choose the answer that does not describe an anti friction bearing

A

High contact area between moving parts

626
Q

Plain roller bearings are designed to support radial loads only

A

True

627
Q

Needle bearings are

A

Most often used where space is limited

628
Q

Choose the term that beat describes static seals

A

They seal between non moving parts

629
Q

O-rings may be replaced with silicone of needed

A

False , silicone is only used used a a sealant in place of a gasket

630
Q

Choose from the following the sentence that best describes gaskets

A

Metal gaskets can usually withstand higher pressures and temp

631
Q

Silicone may be used with cork or paper gaskets

A

False , so not use silicone with cork or paper gaskets as the gasket may slip out or become too thick

632
Q

Choose the term that beat describes face seals

A

There is a little or no wear on the moving shaft

633
Q

Choose the answer that best relates to preload

A

Preload is set by shims , spacers or a threaded ring

634
Q

Brinelling is

A

Indentation from shock loading

635
Q

With regard to bearings, arcing is a term used to describe :

A

Marks on the bearing due to discharges of electricity within the bearing

636
Q

List three contributing factors that lead to abnormal bearing fatigue

A

Speeds that are more than bearing rating is
Shock loads
Vibration

637
Q

Bearing failure is most often attributed to

A

Contamination ingested from external sources

638
Q

When removing bearing from a shaft using the non destructive method

A

Ensure the bearing is supported as close to the shaft as possible

639
Q

Explain the procedure to Han pack a bearing

A

Clean and inspect the bearing . Using clean hands , place grease in palm of one hand , push larger bearing opening down onto grease papers on opposite side . Rotate bearing and keep repeating procedure

640
Q

When heating bearings , so not use

A

Flame

641
Q

Bearings should not be heated above

A

250F (120*C)

642
Q

Fifth wheel couplings are used to connect a semi-trailer to

A

A tractor
Converter dolly
The lead trailer of a B train combination

643
Q

The fifth wheel component that provides the bearing surfaces for the weight o the front of the semi-trailer is the

A

Top plate

644
Q

The purpose of the coupling jaws in a fifth wheel is to engage and secure the trailer

A

True

645
Q

Fifth wheel assemblies are rated on four considerations. What are they?

A

Towed vehicle weight TVW
Maximum expected drawbar load
Vertical load to be carried by the fifth wheel
Type of operation

646
Q

Four advantages of sliding over stationary fifth wheels are

A

Weight can be transferred between tractor axles
Trailers with different kingpin settings can be accommodated
Vehicle length can be varied
Additional manoeuvrability can be gained

647
Q

Which of the following fifth wheels is the most commonly used fifth wheel?

A

Semi-oscillating type

648
Q

Pintle hooks designed to remove the clearance between the hook and the drawbar eye are called …

A

No slack pintle hooks

649
Q

The function of the safety restraint on a trailer unit coupled with a pintle hitch is to …..

A

Ensure that the trailer remains attached to the towing unit in the event of a trailer hitch separation

650
Q

List four fault that can be identified by visually inspecting a fifth wheel

A

Cracked, bent , broken or damaged components
Missing parts
Loose or missing fasteners
Condition of locking devices as cotter pins
Tip plate wear or warpage
Rusting or corrosion

651
Q

Excessive clear wine between the fifth wheel jaws am the lock tester kingpin is a result of …

A

Improper jaw adjustment

Excessive jaw wear

652
Q

The amount of wear in fifth wheel oscillating pins an bushings can be checked by

A

Barring the top plate up and down as well as back and forth

653
Q

A distorted or cracked fifth wheel too plates at be straightened or welded before it can be rebuilt

A

False . A top plate must not be welded or straightened because it will weaken

654
Q

The contact surface of the fifth wheel too plate is lubricates with

A

Water resistant lithium based grease

655
Q

What two fifth wheel components should be lubricates with a light lubricating oil?

A

Cam track path and pivot point

Rack and slide path on sliding fifth wheels

656
Q

A trailer kingpin must be replaced if it is bent more than 1*

A

True

657
Q

A trailer king pin must be replaced if it’s diameter is worn more than:

A

3mm 0.125in

658
Q

Before backing a tractor into a semitrailer you must:

A

Inspect the fight wheel for damage
Ensure the slider plungers are engaged
Check that the lick jaws are open

659
Q

Trailer air and electrical connections can be made after the trailer is securely coupled to the fifth wheel

A

False ,the connection must be done before coupling in order to set the trailer brakes

660
Q

Why test must be performed after the trailer is coupled to the fifth wheel?

A

A pull test must be performed by gently pulling against the trailer parking brakes

661
Q

The first step in uncoupling a tractor semi trailer combination is to

A

Position the unit on dorm , level ground

662
Q

When operating the landing gear to disconnect a semitrailer , use high speed until the skid pads contact the ground and then shift to low speed for 4 to 8 additional turns.

A

True

663
Q

Two common types of landing gear are

A

Drop leg

Gear operated landing gear

664
Q

The condition where gear set input speed is reduced and torque is decreased. Is called:

A

An underdrive

665
Q

A gear set has an input hear with 22 teeth and an output gear with 83 teeth.
The resulting gear ratio is ….
The ratio is called….

A

3.77:1

An under drive or gear reduction

666
Q

When a gear-operated landing gear is operated in low speed , crankshaft speed is …. Though gears before being applied to the lift screw

A

Reduced

667
Q

During high speed operation, the gear box in the landing gear provides a gear ratio of 0.62:1. This ratio is an

A

Overdrive

668
Q

Lifting and lowering the trailer must be done with the landing get in hight speed

A

False, lifting and lowering must be some in low speed to prevent damage to the gear set

669
Q

If the landing gear will not stay in hear while cranking , a possible cause could be:

A

Faulty shift ball and spring

670
Q

The gears in the landing gear are lubricates with

A

Grease

671
Q

One possible cause for frame sideway is :

A

An accident , collision or rollover

672
Q

The difference between frame sag an bow is ….

A

One is bent up and the other is bent down

673
Q

Corrosion of frame material can be a result of:

A

Climatic conditions(rain, snow, ambient temp)
Exposure to certain cargo materials
Contact between two dissimilar metals such as aluminum and steel

674
Q

Four factors that accelerate frame stress and therefore the possibility of frame cracking are:

A

Overloading
Unevenly distributed load
Operating on rough terrain
Loose or worn crossmember attaching bolts

675
Q

Improper frame alignment can be a source of tracking and alignment problems?

A

True

676
Q

When marking a frame rail, you should use :

A

Chalk or soapstone

677
Q

Two reasons for using hardened washers in bolted frame connections are:

A

To prevent the was of the bolt and nut from embedding into the attached part or frame rail
To help distribute the load preventing localized over stressing of frame parts

678
Q

One advantage of using Huck fasteners for attaching frame components is they:

A

Do not allow flexing of frame components

679
Q

Heat treated frame rails must be heated in order to straighten them?

A

False

680
Q

A vehicle equipped with a leaf spring suspension is leaning to one side . A possible cause of this fault is:

A

Broken leaf springs

681
Q

List three possible causes for an air spring suspension to bottom

A
Low system air pressure 
Excessive ride system air leakage 
Air spring cut or punctured
Maladjusted ride height control valve 
Faulty ride height control or dump valve
682
Q

State the procedure for checking shock absorber operation

A

Remove the lower shock mount and then pull the shock piston rod out and push it in 4 or 5 times . You should feel resistance to shock absorber movement in both directions but greater resistance when the piston rod is pulled out

683
Q

It is acceptable to replace a single leaf in a leaf spring assembly if an individual leaf is damaged

A

False

684
Q

A compound like Alumilastic is used on the surfaces of aluminum suspension components that contact other metals because it :

A

Prevents corrosion reactions

685
Q

The trust from a properly aligned drive axle will act ….

A

Along the frame centreline

686
Q

Equalizer beam end bushing clearance can be checked by ….

A

Jacking the beam end up with a hydraulic jack and checking beam end movement

687
Q

The beat way to remove equalizer beam end and centre bushings is to:

A

Use appropriate presses and pullers

688
Q

The difference between bar pin and other types of equalizer beam end bushings is …

A

They provide a point of axle alignment adjustment

689
Q

Rubber load cushions have a due omelet number that indicates …

A

The hardness of the rubber cushion which determines it’s load capacity

690
Q

Drivers must drain air reservoirs at least daily in order to ensure that the:

A

Moisture and contamination in the reservoir a will be removed

691
Q

The driver will have difficulty connecting a tractor to a trailer if the ride height on the air spring suspension is adjusted too high .

A

True

692
Q

When the load is removed from a vehicle equipped with an air spring suspension, the ride height control valve will:

A

Exhaust air from the air springs until the correct ride height is reached

693
Q

Adjusting the ride height on an air spring suspension that is equipped with an adjustable valve mounting is accomplished by making a linkage adjustment

A

False

694
Q

Breakdown maintenance is a system of maintaining a machine whereby components are replaced on a regularly scheduled service interval.?

A

False .breakdown maintenance refers to the policy of running a component machine until something breaks . At that time replacement occurs

695
Q

Identify three hidden costs that can occur of a system of breakdown maintenance is followed :

A
Unexpected equipment downtime
Secondary component damage
Reduced equipment life 
Higher overall costs 
High operator and technician turnover
696
Q

Component failure and damage can be classes as primary and secondary . Explain what effect secondary damage may have on a machine

A

Secondary damage could raise the cost of the primary component failure considerably . Numerous sub-assemblies may be damaged because of the primary failure . The extensive damage could increase the amount of time the machine is down for repair

697
Q

Preventive and predictive maintenance systems attempt to reuse the number of unexpected breakdowns . Identify five purposes of a predictive maintenance systems

A

Maintain component reliability at a like new standard
Reduce the possibility of unexpected component failures
Increase component operating service life while reducing operating costs
Meet the service requirements necessary to maintain a manufacturers parts warranty or any extended warranty
Increase the value of a machine on trade in or re sale

698
Q

A preventive or predictive maintenance system requires information about the machine . This can include such things as machine identification and the service work done on a various components . The information could be recorded on an:

A

Computers ages maintenance system
Parts department card system
Service department card system
Accounting department card system

699
Q

Off road machines are often shit down for maintenance after so many hours of operation ?

A

True

700
Q

A system of predictive maintenance attempts to predict or anticipate when a component may fail. This prediction is based in part on a manufacturers suggested recommendations regarding component life span. Identify three other information collection systems that can be used to help make better predictions about component life span and failure

A

Oil analysis and oil filter contamination
Vibration analysis
Heat detection
Component life history

701
Q

A predictive maintenance system where components are replaced at regularly scheduled service intervals has several advantages . Identify four advantages of this type of predictive maintenance systems

A
Increased productivity 
Reduced maintenance costs
Reduced emergency and breakdown time
Reduced secondary damage
Aids in scheduled maintenance
702
Q

A regularly scheduled oil analysis program does not help you predict component problems, long before failure occurs .

A

False . An oil analysis program can definitely assist you in predicting component failure. Regular monitoring , and careful interpretation of the oil analysis results, helps to predict component failure far in advance of the actual failure

703
Q

A careful, conscientious , observant and alert service technician is required to make a success of any preventive maintenance program

A

True

704
Q

The main advantage of using a deck trailer to carry cargo is ….

A

Easy access for loading and unloading

705
Q

A highboy trailer has the deck located :

A

Above the tractor /trailer wheels and suspension components

706
Q

Two advantages of a lowboy deck trailer are:

A

Higher loads can be carried

The centre of gravity of the loads is lower, increasing stability

707
Q

Trailer that protect the load from environmental conditions are called

A

Van trailers

708
Q

Temperature controlled trailers

A

Keep the cargo at a constant temp

709
Q

Tank type trailers are designed to carry liquid cargo only?

A

False , can also carry granular , dry type materials

710
Q

Trailers that can be lengthened or shortened to accommodate loads of varying length are called ….

A

Extendable

711
Q

Vehicle ground pressure is a measure of:

A

The amount of force creates by the combined weight of the vehicle and it’s load divided by the area of contact between the vehicles tires and the road surface

712
Q

What type of coupling device is used to connect a pony trailer to a body loaded truck ?

A

Pintle hook

713
Q

How many points of articulation are there on a body loaded truck and pony trailer ?

A

1

714
Q

A tractor and single semitrailer are connected using a ….coupling an has ….point of articulation

A

Fifth wheel

One

715
Q

The unit that takes some of the weight off of the tractor when oversized loads are being hauled is called a:

A

Jeep

716
Q

On a A train combination with two semitrailers , the following semitrailer is connected to the lead trailer by a :

A

Converter dolly

717
Q

B train combinations are more stable during operation than A trains because ….

A

The following semitrailer is connected to the lead trailer by a fifth wheel and kingpin connection that provides only one point of articulation

718
Q

The device that connects the following trailer to the lead trailer by two or more pintle hooks, couplers and drawbars is called a :

A

C train dolly

719
Q

An axle that causes the wheels to track parallel to the trailer frame rails at all times is called a …..

A

Fixed axle

720
Q

Steering axles are used on some trailer units to….

A

Prevent tire scuffing when the tractor/trailer combination negotiates a right turn

721
Q

Name two basic styles of wheels used on heavy equipment :

A

Spoke wheels

Disc wheels

722
Q

Explain the main differences between the two wheel styles spoke and disc

A

Spoke wheels are supported by a bearings and can be considerately as a type of hub
Disc wheels are fastened to a hub

723
Q

Identify the two types of disc wheels in term of how they are piloted

A

Stud piloted-centred by the studs and nuts

Hub piloted-centred by the machined hub pads

724
Q

When dual tires and wheels or rims are used , a spacer must be also be used. Explain the purpose of the spacer:

A

The spacer ensures that the two tires are separated sufficiently to prevent contact during normal operation

725
Q

It is permissible to use any style of wheel nut when mounting stud piloted wheels ?

A

False.only use cone/ball type tapered wheels nuts

726
Q

It is permissible to use one stud piloted wheel and one hub piloted wheels as a dual wheel set?

A

False. Only use a set of stud piloted OR a set of hub piloted wheels as a dual wheel set

727
Q

Identify two main types of tires, in terms of the air retention methods.

A

Tube type

Tubeless type

728
Q

Tire tread designs can be of two general styles . Name and explain when those styles are typically used

A

Rib-non-traction , steering on-highway use , trailer

Lug or block-traction application

729
Q

Explain the two major types of tire construction in common use

A

Bias ply-angled cords (plies) built up into layers

Radial ply-steel plies at 90* to the bead , with steel reinforcing belts in the thread circumference

730
Q

Tires are matched by checking the size on the side wall of the tires

A

False . Tires must be measured for circumference and diameter and be matched whit in allowable limits

731
Q

Identify the equipment that could be used to measure tires in the process of matching them together

A

Tape measure
A matching stick , a large square (large calliper)
A tire straight edge or a length of string held tightly across all tires

732
Q

When matching tires on a tandem axle assembly , the front axle tire set can be matched , but slightly different from a matches rear axle tire set

A

False. Ideally both axles tire sets are identically matched

733
Q

Identify the two main tire inflation problems. Of these two explain which is worse and why

A

Under inflated -worse heat can destroy tire

Over inflated -faster tire wear

734
Q

As an apprentice , explain what you could do to prevent personal injury when working around tires/wheels and rims

A

Get training

735
Q

Explain what visual checks you should do before moving any tire assembly

A

Visually inspect the tire/wheel /rim for signs of overheating, damage, cracks and mismatched parts

736
Q

Describe the first thing you would do prior to removing a tire assembly from a vehicle for repair or before working on a loose tire assembly

A

Remove all air from the tire by removing the valve core. Push a wire into the valve stem to ensure no blockage exists and all air is out

737
Q

It is permissible to weld or braze I a steel wheel?

A

False. Do not weld , braze, rework or heat a wheel or wheel components.

738
Q

Describe the equipment you would use to safely inflate a tire and wheel or rim assembly

A

Place tire assembly in a safety cage. Use a length of air hose with a pressure gauge and an inflating/deflating mechanism attached. Stand clear and seat the beads with no more than 276kPa (40psi)

739
Q

It is permissible to mix wheel and rim side rings and lock rings ?

A

False . Never mix wheel/rim components . Always match the parts together

740
Q

Axle wheel hubs generally use a set of two tapered bearings. These bearings do not require adjustment ?

A

False bearings operating as sets must be adjusted

741
Q

Wheel bearings are only lubricated by grease

A

False. Oil is often used

742
Q

All wheels studs have right hand threads

A

False . Some have left hand threads

743
Q

Identify the two general types of wheel balance problems

A

Static -centralized heavy spot across a thread or rim

Dynamic- heavy spot on a side of a tire thread or wheel rim

744
Q

Which tire imbalance is identified by the word bounce ?

A

Static imbalance

745
Q

Which tire imbalance is identified by the word shimmy?

A

Dynamic imbalance

746
Q

Wheel weights used for balancing tire assemblies must be a specific shape and contour

A

True

747
Q

Cracks in steel wheels can be welded and the wheel can then be returned to service

A

False . Never weld a cracked wheel

748
Q

To prevent internal tire and wheel/rim damage air lines should be free of water and oil

A

True

749
Q

Wheel or rim chording is used to describe flat spots on the wheel/rim edges

A

True

750
Q

Long tire life is only obtained by a joint effort between the operator and the service technician

A

True