Het1 Flashcards
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
A raised vehicle should not be worked under until supported by safety stands or blocking
True
26
The pounds per square inch load on the ground can be reduced under a jack by
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
All jacks and stand used with heavy equipment have the same load capacity
False
28
If a height adjustment pin for a jack stand has been lost , you can use a grade eight bolt to replace it
False
29
Equipment can be raised to the height required by using jacks , ramps or hydraulic attachments
True
30
Who is responsible for providing workers with WHMIS training?
The employer must provide the training
31
Employers are responsible to:
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
Suppliers of controller products are responsible to:
Provide MSDS for controlled product they sell or import
33
Employees are responsible to:
Apply workplace labels where and when required
34
The key elements of WHMIS are
Employee education , MSDS and product labelling
35
The goal of WHMIS is to
Protect the worker by providing information on hazardous materials
36
An MSDS must be provided for each controlled product because they
Provide more detailed information than can be provided on a label
37
The supplier label is attached to the
Container in witch the product is shipped
38
Hat section of MSDS would include information on personal protective equipment
Section 7 preventatives measures
39
What is an example of an engineering device used to protect workers from airborne contact with hazardous materials?
Ventilation system
40
How do you identify a portable gasoline container that is approved for use ? It:
Is approved by aether one or both of the ULC or CSA
41
What is the definition of occupational exposure limit(OEL) ?
The maximum concentration of a hazardous substance that a healthy person can be exposed to without suffering adverse health effects
42
Minimum air circulation requirements for the work site are found in the:
Provincial and national building codes
43
Before entering a confined workspace you should
Use a gas detector to determine whether the area contains any dangerous fumes or gases
44
What type of fire extinguisher is versatile in fighting different types of fires?
Multi purpose dry chemical
45
When should you fight a fire for personal safety reasons?
The fire could block your escape route
46
What are the four steps of proper portable fire extinguisher use?
Pull pin, aim the extinguisher , squeeze the handle, sweep the extinguisher from side to side
47
Witch of the following portable fire extinguisher ms should be used to fight a small fire burning in a pile of discarded oily rags
Classes ABC
48
A class C fire involves
Electrical Equipment
49
What part and section of the OHS code describes the membership of a joint work site health and safety committee?
Part 13 section 197
50
What part and section of the OHS code describes the requirements and options for protective footwear
Part 18 section 233
51
What part and section of OHS code describes the requirement for worker training about WHMIS
Part 29 section 397
52
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?
1 emergency first aided, 1 standard first aide, #2 first aid kit
53
What is an employer responsibility with regard to hazard assessment at the work site?
To develop a plan to eliminate or control any hazard identified at the work site
54
How is the Workers compensation board of alberta funded?
100% of the funding for the WCB comes from employers in Alberta
55
What are the four categories of workplace hazards?
Biological, chemical, ergonomic, physical
56
What is an example of an engineering control for worker protection?
Isolation
57
When is an administrative control put in place for worker protection?
When an engineering control cannot eliminate or control a hazard
58
Who is responsible to have an emergency response plan in place at the work site?
Employers
59
What part of the OHS code covers first aid requirements at the work site ?
Part 11
60
What must your employer do if first aid supplies are stored in secure containers at the work side
Ensure that the containers are clearly marked to indicate their contents
61
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?
2 standard first aiders
62
What is the duty To use personal protective equipment according to the Alberta OHS code?
What you and your employer must do if a hazard assessment identifies the need for the use if PPE
63
Who is responsible to ensure work site emergency response plans remain up to date ?
The employer and the employees
64
When a work site hazard assessment identifies that workers are required to wear PPE what is your employers responsibility?
Ensure all workers properly use and wear the required PPE
65
What is an employee responsibility with regard to the use of PPE
To inspect your PPE prior to each use
66
Industrial protective headwear must comply with what standard ?
CSA
67
What is not an obligation your employer assumes when a hazard assessment indicates the need for PPE?
To post a duty to use PPE sign at all entrances to work site
68
What is a characteristic of protective footwear with a yellow triangle on the outer side or tongue of the right shoe?
Sole puncture protection and the grade 2 protective toe ( will withstand impact up to 90 joules)
69
In what situation is your employer obligated to provide you with proper PPE according to the OHS code?
When workers are exposed to respiratory hazard or excessive noise levels
70
Witch of the following vehicles does not require yearly commercial vehicle inspection?
Farm vehicles
71
Ferrous metals are metals that:
Have an iron base
72
Threads for vast iron are usually a coarse tread ?
True
73
Which of the following ha the lowest melting point?
Lead
74
Choose the statement which best describes elasticity
Elasticity is the ability is a material to be stretched and still return to it's original shape
75
When steel is heated to a high temperature and cooled slowly, the metal will be:
In a softened state , easy to work
76
Vulcanizing rubber refers to:
Heating raw rubber with sulphur to alter it's properties
77
What is the health hazard when working with asbestos and fibreglass?
Hazardous when inhaled
78
Which of the items listed below would be best to form a gasket ?
Silicone
79
Nylons are being used in industry as a replacement for metals?
True
80
A cap screw with a thread pitch of 1/24 inch has:
14 threads per inch
81
Thread series refers to the
Type of tread : UNC,UNF,UNEF, NPT
82
Explain by short answer or sentence form , how tensile strength is indicated on imperial and metric fasteners
```
IMP lines indicate strength
MET numbers indicate class ex8.8 10.9
```
83
What do the numbers 10-24 refer to in regards to machine screws?
10-diameter
| 24-treads per inch
84
Lock washers are not suitable for use with which of the following screws ?
Aluminum
85
A fastener with 6 radial marks on the head ha a tensile strength of:
Eight
86
A fastener has resistance going into a threaded hole. This resistance to turning is called:
Run down forgive and must be added on to the full torque
87
What is another name for a Woodruff key?
Half moon key
88
Besides securing and driving components , what other function is performed by a helical spline?
A helical spline offsets end or axial thrust
89
Applying a lubricant to the threads of a fastener and using a dry torque specification will:
Increase the clamp load compared to dry threads
90
Split and roll pins should be installed with what kind of a tool?
Roll pin punch for the size of the pin
91
Aerobic sealers are those that require air to enable them to cure
True
92
Explain the function of a small ring
Installed in to a groove for a object to ride against
93
If a fastener with thread locker or locktite is difficult to remove , you should :
Apply heat
94
In an electric brake wheel assembly , witch components are similar to those used in hydraulic drum brake systems ?
Brake shoe, return springs an associated hardware
Brake drum friction surface provides a similar function
Backing plate and anchor assembly
95
In an electric brake wheel assembly , which components are unique to the electric brake system?
Electromagnets , actuating lever and block assembly
| Brake drum inner machines surface is special
96
What is the function of the electric brake controller?
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
In an emergency situation the electric trailer brakes will be able to provide the total braking requirements needed by truck and trailer combination
False, the trailer brakes will never be able to provide total braking required by the combined tow vehicle and trailer
98
When you are using an ammeter to check the trailer brakes, a high amperage draw reading could indicate.
A short circuit in the electromagnet
99
Explain the function of the auxiliary breakaway battery located on the trailer
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
Provide reasons why electric brake systems may develop electrical problems between service intervals
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
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
False, small movement should cause small voltage increase
102
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
Small lever movement-low voltage to brake
Large lever movement- higher voltage to brake
Full lever movement-maximum voltage to brake
103
The truck brakes and the trailer brakes are synchronized by adjusting the brake controller during a series of road tests
True
104
List two alberta governments acts, regulations or programs relating to vehicle safety
Motor transport act
Commercial vehicle inspection program
Commercial vehicle standards alliance
105
A vehicle on which you did a brake job has been involved in an injury accident . The owner can sue your employer and you
True
106
Asbestos is a health hazard. What can you do to protect yourself from this material?
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
Injuries can occur around heavy equipment and components . How can you protect yourself from injury ?
Use hoists, jacks , lifting and moving equipment
Have your co-workers assist when lifting and moving large parts
Lift properly use your legs
108
Flexible brake lines must not bulge or expand outward under high pressure applications
True
109
What is meant by the term maxim diameter as it relates to brake drums?
This is the greatest diameter recommended by the vehicle manufacturer
110
What is meant by the term minimum thickness as it relates to brake rotors ?
This is the thinnest the rotor can be as a recommended by the manufacturer
111
What or who are your sources of information regarding a costumers vehicle brake problems?
```
The vehicle operator
A service advisor
A work order
Your own observation on a walk around
A road test
```
112
What two methods can you use to detect equipment problems once a costumer brings a vehicle to your shop ?
Vehicle walk around , look and touch
| Vehicle road tests , listen and feel
113
What safety precautions should you observe before working on or under a vehicle ?
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
Why would you only work on one brake assembly at a time on the same axle?
The assemble side is a reference for checking your work
115
Drum diameter out of round and taper are three checks used to determine brake drum condition.
True
116
A brake drum that has a crack in it can be welded and returned to service
False
117
A new brake drum and a used brake drum can be used an the same axle?
Not normally unless the worm drum is within 0.010" (0.254mm) of the new drum diameter
118
After machining , brake drums should be sanded with a 240 grit sandpaper . Why is it done?
This removes cutting grooves and creates a non directional finish so the show do not move sideways during applications
119
If brake return springs are discoloured and slightly bent, they can be safely straightened and returned to service
False springs will fail in service or not provide proper tension
120
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
False varsol itself is oil based and will contaminate lining and friction surfaces
121
During inspection , brake rotors are measured for :
Parallelism
Lateral runout
Rotor thickness
122
What two methods are used to mount brake linings to brake show and brake pads?
Bonding and riveting
123
Prior to pad removal and calliper disassembly , what precaution should be taken before pushing the pistons back into the caliper bores ?
Remove about 1/2 the volume of brake fluid from the disk brake reservoir in the master cylinder
124
Rotor thickness should be the same from one side of the vehicle to the other on the same axle
True
125
When the caliper is unfastened from the anchor plate what safety precaution should be followed ?
Hang the caliper from a stable point to prevent damage to the flex hose
126
Wheel bearings which are adjusted too loosely can have negative effect on braking
True
127
Explain why wear indicators are used with disc brake pads
Wear indicators provide an audible and or visual warning of reduced pad lining thickness. This helps prevent rotor damage
128
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
True
129
Aluminum master cylinders and aluminum wheel cylinders should not be honed as part of a repair process
True
130
What fluid is suitable for use when honing a brake cylinder?
Brake fluid
131
Grease or oil on rubber brake parts poses no problem for the parts of the system
False grease and oil can cause rubber parts to swell
132
A force of 800N is applied to a master cylinder with an area of 8cm*2, the system pressure developed is
1000kpa
133
A brake system develops 350psi on application.the force produced at a caliper piston with an area of 2.75 in/2
962.5lb
134
A 0.5 cm diameter master cylinder is replaced with a 2.5cm diameter cylinder . The result is:
Less pressure in the system
135
One of the reason DOT 5 brake fluid is not recommended for ABS systems is because it:
Is not hygroscopic
136
The poly glycol-based brake fluid that has the most stable boiling point is :
Dot 4
137
The hydraulic brake system converts kinetic energy to heat energy through:
Friction
138
Brake fluid should be stored only in a sealed container because :
The fluid is hygroscopic
139
Friction between two sliding surfaces depends on:
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
The principle of static friction is used in:
The park brake system
141
Pressure in an enclosed liquid :
Acts with whisk force on equal areas
142
The wheel cylinders and calipers convert pressure developed in the system into:
Mechanical force
143
The force that tends to resist motion between objects in contact is called :
Friction
144
Name three categories of power assist brake systems
Vacoom buster system
Air over hydraulic
Hydraulic over hydraulic
145
Explain why vacuum type power brake boosters are not generally used on vehicles with a Diesel engine
Diesel engines do not create sufficient vacuum to effectively operate boosters
146
To determine if a vacuum booster is vacuum suspended
The engine must be running
| Vacuum must be on both sides of the power diaphragm
147
Describe a quick test of a vacuum booster system to see of any boost exists at all
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
Vacuum boosters work because a difference exists between a low pressure are and a high pressure area
True
149
Air over hydraulic booster systems are typically used when the vehicles has gasoline engine
False
150
Air used in the air over hydraulic booster systems is:
Compressed air
151
Water in the air supply system used with air over hydraulic booster systems does not have a negative effect on booster operation
False
152
In the air over hydraulic brake booster system , a special hydraulic oil is used in the hydraulic system
False
153
Hydraulic over hydraulic power brakes use fluid in two separate systems. This is described more accurately as:
Hydraulic fluid over brake fluid
154
In the hydraulic over hydraulic system , pressure for the hydraulic systems is normally supplied by an
Power steering pump
155
What type of fluid might be used in the brake system of a hydraulic over hydraulic brake system?
DOT 3DOT4DOT5 brake fluid
DOT 3 and 4 can be mixed
DOT 5 is used alone
156
Valve bodies that have deep scores can be honed and reused
False
157
The equalizer bracket is used between the hand brake cable and the cables leading to the rear wheels
True
158
Park brakes may use a cable as an actuating device . The cable length is adjusted after all other adjustments
True
159
A driveshaft type of parking brake may be rendered ineffective if
The driveshaft or a universal joint is broken
The driveshaft is disconnected or removed
One rear wheel is jacked up off the ground
160
Brake drums used on medium duty trucks are usually made from the following material
Cast iron or centrefuse
161
Disk brakes have both servo and self energizing action
False the rely on clamping force
162
A horizontally mounted master cylinder has a primary and secondary piston. The primary piston is the first one activated by the brake pedal pushrod
True
163
Double flares and ISO flares are two types of flares used on steel brake tubing
True
164
Steel tubing with double flares can be used with fittings that are designated ISO flares
False double flares and fittings must never be interchanged with ISO flares and fittings
165
To protect brake line fittings from damage the following tools should be used
Line flare nut wrenches
166
Pressurized brake fluid moves the piston seal and the piston in a drum brake wheel cylinder
True
167
Pressurized brakes fluid moves the piston seal and the piston in a disk brake caliper
False fluids move piston only
168
Wheel cylinders are mounted on backing plates. Calipers are mounted on anchor plates
True
169
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
True
170
List 4 functions of hydraulic oil
Transmit power
Lubricate
Seal
Cool
171
Te term viscosity refers to an oils
Internal resistance to flow
172
The two most common oil viscosity grading systems are :
Society of automotive engineers (SAE)
| International standards organization (ISO)
173
Viscosity index VI refers to
The amount that the oils viscosity changes with temperature
174
Boundary lubrication refers to a condition where:
Minute imperfections on the surfaces of moving parts are in contact
175
Define the term oxidation as it relates to hydraulic oil
Refers to the reaction of the hydraulic oil with oxygen in the air
176
Three factors that will determine how quickly a hydraulic oil will oxidize are
The amount of air that the oil is exposed to
The oil temp
The chemical makeup of the oil
177
The most important consideration when selecting a hydraulic oil is
Manufacturers specifications
178
State three functions of the hydraulic reservoir
Holds the system oil supply
Cools the oil
Allows air and contamination to settle out of the oil
179
The ideal capacity for a hydraulic tank is
Between 2to 3 times the pump flow rate
180
Pressurized reservoirs are used in applications where
The pump inlet line may not otherwise be filled with oil
181
What procedure must be done before you service a hydraulic system equipped with a pressurized reservoir
Depressurize the reservoir
182
List three functions of the baffle plate in a hydraulic reservoir
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
Contamination in a hydraulic system comes from the following three sources
Built in contamination
Ingreases contamination
Internally generated contamination
184
The greatest amount of component wear is caused by contamination that is
The same size or smaller than component internal clearances
185
Contamination that restricts the flow of lubricating oil to components
Larger than component internal clearance
186
Coarse filters are called
Strainers
187
Mesh or sieve number refers to
The numbers of openings per liners inch
188
A filter having Beta Rating of B10=1 indicates that the filter removes
None of the 10qm contamination
189
The filtering device most commonly used in the pump inlet line is a
100 mesh strainer
190
The most common filter location on mobile heavy equipment hydraulic systems is
In series in the return line
191
The most common filter location on mobile heavy equipment hydraulic systems is ...
In series in the return line
192
The pressure drop created by filter media is a result of:
Oil viscosity
| Filter media permeability
193
The function of the filter bypass valve is to:
Prevent damage to the filter caused by excess pressure
194
Steel pipe sized by...
Nominal inside diameter and wall thickness
195
The term that refers to the wall thickness of steel pipe is:
Schedule number
196
One disadvantage of using steel pipe is a hydraulic conductor is that it:
Cannot be bent
197
Steel tubing is sized by...
Outside diameter and wall thickness
198
Te main advantage that tubing connectors offer over pipe connectors is that:
They do not use connectors threads to seal the connection
199
State the flare angle of the following connectors :
Joint Industrial Council (JIC) 37*
| Society of Automotive Engineers (SAE) 45*
200
Split-flange connectors seal the connection by using:
An o-ring
201
Hydraulic hose that is designated by a ,,-12" (dash 12) has an :
Inside diameter of 3/4 in
202
Two common types of reusable hose connectors are:
Screw on socket type
| Press on sleeve type
203
Hydraulic oil coolers are usually connected in... In the system ....line
Series
| Return
204
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 ?
94%
205
As pump outlet pressure increases, the pump's internal leakage decreases .
False
206
Why I some internal leakage necessary within all hydraulic pumps?
Because lubricates moving pump parts
207
The two factors that determine the amount of internal leakage in a pump are:
The pressure difference between the pump inlet and outlet ports
The amount of internal clearance within the pump
208
Te most common cause of pitted erosion on the internal surfaces of the pump is :
Cavitation
209
The hydraulic pump converts.....energy to.... Energy.
Mechanical
| Hydraulic
210
A hydraulic pump creates pressure
False
211
The most important characteristic of a non-positive displacement pump is that...
Inlet and outlet ports are hydraulically connected
212
Which of the following is a non-positive displacement pump?
Engine water pump
213
The main advantage of a positive displacement pump over a non positive displacement pump is that...
Flow does not decrease significantly as pressure increases
214
The two factors that affect pump flow rate are...
Pump displacement
| Input shaft speed
215
Pump displacement refers to ...
The volume of liquid that a pump delivers in one revolution
216
A 100cm3 /rev pump that is driven at 1500rpm produces a flow rate of:
150Lmin
217
The term used to express the amount of power required to overcome a pump's internal friction is
Mechanically efficiency
218
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%?
262.20L/min
219
Cavitation occurs in a hydraulic pump when:
Inlet pressure falls too low
220
Pump inlet pressure is affected by...
Pump inlet restriction
| Pump drive speed
221
The most common cause of hydraulic pump aeration is
Air leakage on the inlet side of the pump
222
When a three stage telescopic hydraulic cylinder is operated the greatest force is generated when the:
First stage is extended
223
Double acting hydraulic cylinders differ from single acting cylinders in that they ...
Hydraulically extent and retract
224
In it's normal position , a normally closed pressure control valve blocks oil flow from it's inlet port to it's outlet port?
True
225
The term that describes the pressure when a direct acting , normally closed pressure relief valve initially begins to open is:
Cracking pressure
226
The term that describes the pressure relief valve is fully open is:
Full flow pressure
227
Single acting hydraulic cylinders :
Hydraulic actuate in one direction
228
Single acting hydraulic cylinders are returned by:
Some external force
229
The definition of a fluid is...
A substance that flows
230
The major difference between linguists and gasses Is that:
Liquids resist compression
231
State Pascal's Law .
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
Pressure in a hydraulic system is created by:
Resistance to liquid flow
233
Pressure losses in a hydraulic system are created by ...
Resistance to flow that is created by system components
234
Pressure is defined as ...
Force per unit area
235
As the force applied to a confined liquid increases , pressure :
Increases
236
As the area that a force is acting on increases , pressure:
Decreases
237
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)
A4
B3
C2
D1
238
The pressure resulting from 125kg acting on a circular area with a 25cm diameter is :
25kPa
239
As the pressure acting on an area increases, the resulting force:
Increases
240
An increase in the area that a given pressure acts upon causes the resulting force to :
Increases
241
The pressure resulting from 450kg acting on a circular area with a 20cm diameter is:
140.37kPa
242
Pressure created by the weight of a fluid is called ...
Pressure head
243
A pressure measurement that includes atmospheric pressure is:
An absolute pressure measurement
244
List six safety precautions you must take when working on hydraulic equipment :
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
A resistance reading of infinity or out of limits(OL) indicates a:
Resistance higher than the meter is capable of reading
246
A resistance reading of 2.4M ohms could be expressed as:
2 400 000 ohms
247
The term impedance , as related to electrical test equipment , indicates:
The amount the test equipment will load the circuit
248
The first step in operating a digital multi meter should be to :
Read manual
249
A low resistance conductor that is connected in parallel with the ammeter's digital display is called a:
Shunt
250
When using the Ohm meter function of a digital multimeter , holding the two test leads together , a reading of ... Is expected
0 Ohm
251
When using a digital multimeter to measure amperage , what protects the meter from having too much current run through it?
Internal fuse
252
A high impedance digital meter should be used when measuring electronic circuits to reduce the:
Possibility of circuit damage
| In accuracy of meter readings due to meter loading
253
Measuring the source voltage with no loads connected is known as measuring open circuit voltage?
True
254
What digital multimeter automatically sets itself to the most accurate range within each function?
Auto ranging
255
When using a digital multimeter to check... The meter is connected in parallel to the source of voltage
Voltage
256
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
Amperage
257
Meters equipped with a .... Have an internal battery to power the meters electronics
Digital display
258
Of the .... Is reversed on a digital multimeter , the digital display indicates a negative (-) sign
Polarity
259
You should always use a ... Digital meter when measuring sensitive electronic circuits
High impedance
260
The use of .... Is recommended on any curch it's especially those containing electronic components
Test light
261
When using a digital multimeter to check ... Never connect the meter to an energized circuit
Resistance
262
To read positive amperage reading , the arrow on the ammeter's.... Is always pointing towards the battery's negative terminal
Inductive clamp
263
The first step in the battery service is to:
Ensure that you are wearing safety glasses or a face shield
264
Battery negative plates and positive plates with separatists between them are called a :
Element
265
A battery :
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
A maintenance free battery :
Can be visually inspected and load tested for reuse
267
Parallel connections within the battery result in :
Same voltage with increases current production
268
The electrolyte in a lead-acid battery is made up of water and:
Sulphuric acid
269
Each fully charged battery cell produces approximately :
2.1 volts
270
When a battery is discharged :
All plates have changed to lead sulphate (PbSO4)
271
Acid spills can be neutralized with a mixture of:
Baking soda and water
272
When removing the battery from a vehicle for servicing , always remove the:
Negative (ground) cable first and install it last
273
Before you perform a battery load test , the battery must be at least :
75% charged
274
An open circuit voltage test is performed on a battery to determine:
The state of charge of the battery
275
If a battery load test is performed on a 12 volt battery at room temperature , the final voltage should be :
Greater than 9.6 Volts
276
When servicing a battery with tapered terminals , three necessary tools are :
Battery pliers, a terminal puller and a terminal spreader
277
A fully charged battery is best stored:
In a cool or cold location
278
If a battery is stored in a discharge condition , it:
Will freeze
Will become sulphated
May not recharge
279
If a battery In a stored vehicle discharges over a period of three days
There might be a parasitic drain in the vehicle
280
A battery will supply the most power when it is:
At room temperature
281
Prior to charging a battery , it is most important that:
The plates are submerged in electrolyte
282
The time required to recharge a battery depends upon:
The charger amperage output
The battery's state of charge when charging begins
The battery's rated capacity
283
When boost charging a vehicle , the:
Ground cable should be connected the the boosted vehicle engine block or frame last
284
The total current carrying capacity of multiple series battery groups :
Remain the same with the addition of every battery
285
When replacing batteries in groups , you should:
Plan ahead
| Replace with batteries of the same age , type , capacity and manufacturer
286
Magnetic flux lines :
Cannot be insulated
287
Like magnetic poles :
Repel
288
A permeable material means that:
Flux lines concentrate in it
289
The following listed material with lowest permeability is :
Aluminium
290
Three characteristics of the direction of magnetic flux lines are :
Have direction from North to South Pole
Take the shortest path
Repel one another when they have the same direction
291
A permanent magnet loses magnetic strength when:
Exposed to shock
292
The three factors that affect the strength of an electromagnet are:
Number of turns of wire within the coil
Voltage applied to the coil
Type of core material
293
An electromagnetic device that draws an iron core to it's centre is called a...
Solenoid
294
The right hand rule for conductors determines the:
Direction of the magnetic flux lines around the conductor
295
When using the right hand rule for coils , the :
Thumb points to the North pole
296
The magnetic principle used in electric motor operation is called ... And states that...
Motor principle and states that current carrying conductor within a magnetic field will move to an area of the weaker magnetic field
297
Voltage is generated in a conductor when a magnetic field:
Moves at an angle around a conductor
298
The four factors that determine the amount of voltage produces in a conductor are:
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
When current flowing in a coil of wire is stopped :
The air rounding magnetic field collapses
300
Self induction can be stated as:
The process of producing voltage in a coil as the magnetic field collapses when current flow stops results in self induction
301
Mutual induction occurs :
Between two coils or conductors
302
Which of the following systems have movable electrical contacts that carry the systems current flow?
Electrical system
303
Which of the following devices have no moving parts?
Solid state electronic devices
304
Electrical systems can make very fast multiple decisions, remember past events and self diagnose problems
False , electronic systems can do these things
305
In the technology of the semiconductor , the word semi means:
That something is half way between two limits
306
In the technology of the semiconductor , the word conductor means:
That the material allows electric current to flow freely through the substance
307
The base material for manufacture of semiconductors is most often :
Silicon
308
An N type semiconductor is produced when a covalently bonded silicon crystal is doped with:
Antimony
309
A P type semiconductor is produced when a covalently bonded silicone crystal is doped with :
Boron
310
As the temperature of a wound resistance wire resistor rises, it's resistance value:
Increases
311
Resistors are specially constructed devices that can be used to:
Produce heat
Produce light
Limit current flows in electrical circuits
312
Fixed value resistors can have:
Only one resistance value
313
When a resistor's resistance value is checked with an ohmmeter , it must be:
Isolated from any electrical voltage source
314
A diode results when a P type semiconductor is bonded to an N type semiconductor material
True
315
A diode is being tested in a reverse bias connection and an audible signal is heard , the diode is serviceable
False it means the diode is defected and cannot be used
316
A diode testing function can be used to test diodes when using a DMM
True
317
When a diode is being tested in a forward bias connection and an audible signal is heard , the diode is serviceable.
True
318
Electronic control modules need to be protected from vibration
True
319
Excess voltage in an electrical circuit may cause electronic device failure
True
320
Excess current flow through electronic equipment onboard a unit of heavy equipment can be caused by improper:
Welding procedures
Use of a low impedance test equipment
Battery boosting procedures
321
A signal that voltage value is on and the off is:
A digital signal
322
A signal whose voltage value is constantly variable is called a:
Analog signal
323
Signals from ON/OFF switches are
Digital signals
324
Signals from a thermistor sensor are
Analog signals
325
Before they can be used by the central processing unit, analog input signals must be processed in the
ADC
326
All of the components in an ECM are kept at the same pace by the:
Internal clock
327
The device that prepares the output data in a form that can be used outside the ECM is called the:
DAC
328
A combination of eight binary code bits is called
A binary word
329
Input data ca be stored in the
RAM
330
Which type of RAM is connected directly to the battery rather than powered through the ignition switch?
Volatile
| Keep alive
331
The brain of the ECM is called a :
Microprocessor
332
What part of the ECM receives information from the systems inputs?
Microprocessor
333
What kind of memory is used for peahens storage of data?
PROM and ROM
334
Random access memory is
Volatile
| Nonvolatile
335
Which type of memory can you take out of the ECM to write new program information to it?
PROM
336
Which type of voltage sensor uses a predetermined voltage signal that is sent from the ECM?
Reference voltage sensor
337
Which type of voltage sensor produces it's own voltage signal?
Voltage generating sensor
338
The output actuators of electronically controlled systems are :
Electrical motors
Solenoids
Relays
339
On board fault codes can be read directly from the ECM through :
Blinking lights
340
Off board diagnostics are accessed through the use of
Scanning tools
Data link connectors
Scanning tool programs
341
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:
High impedance digital meters
342
A break in the normal path of an electric circuit causes a
Open circuit
343
The amount of current in a circuit is determined by:
Source voltage
| Resistance of the circuit
344
If an open occurs in a circuit , current:
Decreases
345
As applied voltage increases
Current increases
346
Voltage is :
Potential difference
347
Resistance is:
Determined by circuits construction
348
Amperage is :
Measurement of current flow
349
Resistance of a circuit decreases is a
Short occurs in a parallel or series circuit
350
As resistance of a circuit increases
Voltage decreases
351
If a resistor in a circuit is shorted , an ammeter in the circuit would indicate :
More current than normal
352
In heavy equipment 's electrical system, a resistor could be:
A light bulb
A two way radio
A starter motor
353
Reduced current flow in a series circuit can be caused by:
Corroded terminals on the battery
354
An element consists of
One kind of atom
355
Electrons have a
Negative charge
356
The nucleus of an atom has
Protons and neutrons
357
A conductor of electricity is a material that
Allows electrons to move through it
358
Atom consists of three still smaller particles called
Proton
Electron
Neutron
359
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 ...
Proton
Electron
Proton and neutron
360
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
Negative charged
| Positive charged
361
The electrons found in the outermost orbit of the atom are known as
Valence electrons
362
Most insulators are
Compound of two or more elements
363
Voltage is electrical
Force
364
The opposition to electron flow is:
Resistance
365
Resistance of a conductor is determined by :
Length , cross-sectional area, temperature and type of material
366
Current is electrical
Flow
367
Which of the following forms of voltage sources require polarity markings?
Direct voltage
368
Technicians should wear static straps when working on any electronic components to prevent discharges of damaging voltages that are produced by
Friction
369
List two advantages when braking a vehicle equipped with antilock brakes
Directional stability control
| Decrease stopping distances
370
Braking is most effective when the rotation of the wheel an tire is slowed
Without overcoming friction between the tire and the road
371
The antilock air brake system modulates ... To slow the vehicle effectively and under control
Brake application pressure
372
Antilock brake systems can modulate the brake application pressure up to... times per second
100
373
List the basic components of an antilock system
```
Tone wheel
Speed sensor
ECU
ABS lamp indicator
Brake modulation valve
```
374
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?
4S4M
375
The purpose of the tone ring is to
Induce electrical pulses in the speed sensor
376
The antilock systems ECU is a computer that:
Analyzes and processes speed sensor signals
| Controls the brake modulator valves
377
A vehicle is being driven with ABS indicator light illuminated . This indicates to the driver that
There is an antilock system malfunction
378
If the antilock system fails during vehicle operation, the standard brake system will
Function normally
379
The tone rings are most commonly mounted to the
Wheel hubs
380
In tandem drive axle truck chassis with one modulator valve for each side , the modulator valve controls
Two brake chambers
381
Of arc welding must be performed on a vehicle with antilock , the ECU should be
Unplugged or disconnected
382
When removing the hub assembly from an antilock equipped vehicle , a technician must
Take care not to damage the tone ring and sensor
| Support and block the vehicle safely
383
A wheel speed sensor is positioned by
Pushing the sensor in until it touches the tone wheel
384
Most antilock systems specify that all tire sizes must be kept within ... Circumference of each other
3/4"
385
Spring brake chambers apply and him a parking brake application
Without air pressure
386
Caution must be exercised when working around spring brake equipped vehicles because
Spring brakes contain large, powerful springs
387
Air supply for parking/emergency brake operation flows through a double check valve so that the emergency brake will
Not apply of either service reservoir air pressure lost
388
The function of the park control valve is to provide manual
And automatic control of all the parking /emergency brakes on the unit
389
A quick release valve is often used in parking /emergency brake circuits to provide quick
Application of the spring brakes
390
An anti-compounding double check valve is often used in parking / emergency brake circuits to
Release the parking / emergency brakes when the service brakes are applied
391
Some truck / tractor units are equipped with a spring brake valve that
Allows the spring brakes to modulate application if primary service reservoir air pressure is lost
392
A relay valve is used in parking/emergency brakes circuits that use spring brake valves to ensure that the spring brakes
Apply and release quickly
393
The purpose of the trailer service line is to transmit air pressure
To apply and release trailer service brakes
394
The purpose of the trailer supply line is to transmit air pressure
To charge the trailer reservoirs
395
The trailer supply valve supplies air pressure to the trailer from
Both primary and secondary reservoirs
396
In the event that pressure in both primary and secondary reservoirs falls bellow 50 Psi (345 kPa) the
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
The purpose of the trailer brake control valve is to allow the operator to
Independently control trailer service brakes
398
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
Tractor brakes will be applied with 10 psi and trailer brakes applied with 20psi
399
Tractor equipped with a bobtail pro portioning relay valve will reduce
Primary application pressure when tractor is not towing a trailer
400
The brake light switch is a normally
Open switch that is closed by primary or secondary service pressure
401
List nine safety precautions that must be observed when working around air brake equipped vehicles
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
When visually inspecting the compressor mounting security look for
Cracked or damaged mounting brackets
| Loose missing fasteners
403
A properly adjusted compressor drive belt will have a maximum deflection of
1/2 to 3/4 inch
404
Of you discover excessive oil when draining the air reservoirs, the problem is likely
Worn air compressor piston rings and cylinders
405
CVIP specifications state that a vehicle could be put out of service of the brakes chamber pushrod travel does not fall between
3/4 to 1 1/2 inch
406
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
Acceptable
407
The Alberta CVIP states that the vehicle compressor should build up from .... To ... Within 3 minutes
50psi to 90psi
408
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
Faulty governor
409
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
Primary leakage is acceptable but secondary leakage is excessive
410
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
Primary leakage is excessive but secondary leakage is acceptable
411
Pushrod travel for a properly adjusted cam-operated foundation brake should be
As short as possible without drag between the brake linings and drum
412
The angle formed between the brake chamber pushrod and the slack adjuster arm when the brakes are applied should be
Never less than 90*
413
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
Check valve in the primary reservoir
414
Dented or kinked air lines in the parking/emergency brake circuit could cause the springs to
Be sluggish when applied and released
415
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
Immediately apply
| Shut off air to the supply line between 60psi and 20 psi
416
Before you attempt to mechanically cage spring brakes , you should
Inspect the spring brake chamber for damage
417
Before you back off the brake on units that have automatic slack adjusters , you must be sure to
Remove or disengage the adjustment pawl
418
Alberta CVIP states that a vehicle will fail inspection if the radial clearance between the camshaft and bushings is
0.085inch
419
Removing material from the inside diameter of a brake drum results in
Reduce strength
| Reduced ability to dissipate heat
420
Camshaft axial play should not exceed
0.030 inch
421
Alberta CVIP states that an air-brake equipped vehicle will be put out of service if the brake linings are worn below
5/16 inch
422
Camshaft axial play is adjusted by
Adding or removing shims between the slack adjuster and it's retaining snap ring
423
If the angle between the brake chamber pushrod and slack adjuster arm is incorrect , you must:
Adjust the brake chamber clevis
424
It is important to closely watch brake adjustment following a brake reline because
Brake chamber pushrod travel will increase more rapidly than normal as the brake lining wear in to the brake drums
425
Friction
Refers to the resistance between two moving bodies
426
In order to stop a moving vehicle , the braking system must convert moving vehicle energy into
Heat energy
427
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
2000hp
428
Of the weight of a vehicle is doubled , the power requires to stop the vehicle will
BE increased 4 times
429
If both speed and weight of moving vehicles are doubled , the power required to stop the vehicle will
Be increased to 8 times
430
One advantage that air brake systems have is that
The system does not have to bled when connecting or disconnecting trailers like hydraulic braking systems do
431
One disadvantage air brake systems have is that
There is always some brake lag
432
When a given volume of air is compressed to 1/2 it's original volume , it's pressure will
Double
433
When a give volume of air is compressed to 1/2 it's original vole , theoretically it's temp will
Double
434
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
1200lb of force
435
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:
7200in lb of torque
436
The term lag time refers to the time required
For the air system to apply the brakes
437
The component of the basic air brake system that connects the air system to the foundation brakes is the
Brake chamber
438
The component of the basic air brake system that allows the operator to regulate brake application pressure is the
Brake valve
439
The function of the governor is to
Limit maximum air system pressure
440
The slack adjusters
Convert linear motion to rotary motion
Multiply the braking force from the brake chamber
Provide a place for brake adjustment
441
Connecting lines and fittings are important to air brake system operation because they affect
The speed of air flow through the system
442
When an air brake compressor piston is in it's compression stroke , the inlet valve
Is closed and the discharge valve is open
443
When the compressor is in it's unloaded cycle
The inlet valves are held open
444
The governor controls maximum air system pressure by
Putting the compressor in the unloaded cycle
445
The automatic drain valve drains moisture and contamination from the reservoir when
Any drop in reservoir pressure
446
Air brake antifreeze is used in the air brake system to
Prevent moisture in the system from freezing
447
Desiccant type air dryers rely on
Beads that absorb moisture vapour from the air stream
448
Single check valves are installed in the inlet line to both the primary and the secondary service reservoirs because they
Prevent air loss in the event of a failure in the other reservoirs
449
The function of the safety valve is to
Limit air pressure buildup in the event of a governor failure
450
CMVSS121 states the minimum pressure at which the low pressure warning devices must warn the operator is
60psi
451
Nylon air brakes tubing should not be used where it may be exposed to
Hight temp
Abrasive and wear
Excessive movement
452
In the released position , the inlet/exhaust valves of the dual-circuit brake valve are in the following condition
Inlet are closed and the exhaust are open
453
The dual -circuit brake valve holds it's inlet and exhaust valve closed
When the valve is in it's balanced position
454
The function of the relay valve in the primary brake circuit is to speed up the
Application and release of the primary service brakes
455
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
17.5 psi to the primary brake chamber
456
A type 24 brake chamber has an
Area of 24in2
457
During normal brake applications, the secondary section of the dual circuit brake valve is applied by
Primary service air pressure
458
The function of the quick release valve in the secondary brake circuit is to
Speed up the release of the secondary service brakes
459
Properly adjusted cam operated foundation brakes
Keep the brake linings as close to the brake drum as possible without dragging when the brakes are released
460
When a cam operated foundation brake is in the released position , the brake shoe rollers are
In contact with the low cam area
461
The linear motion of the brake chamber pushrod is converted to twisting force at the brake camshaft by the
Slack adjuster
462
Brake drums must be able to
Provide an acceptable braking surface
Withstand hight temp
Resist distortion
463
Brake drum thickness
Affects the drums ability to dissipate heat
464
Cam operated foundation brakes are called
Non servo brakes
465
The term brake fade occurs at excessively high brake temp because the
Brake lining coefficient of friction is reduced
466
Brake lining edge code identifies the lining by
The initials of the manufacturer
The normal coefficient of friction
The hot coefficient of friction
467
Using brake lining with a GAWR that is too low can result in
Brake fade
468
During braking, the brake spider transfers torque from the
Brake shoe to the axle housing
469
Flat brake cams are often used in steer axle foundation brakes because they
Have a slower rate of application than S-cams
470
The foundation brake component that provides a place to adjust brake lining to drum clearance is the
Slack adjuster
471
During application , the angle formed between the brake chamber pushrod and the slack adjuster arm should NEVER be
Less than 90*
472
One of the most frequent causes of brake failure is
Improper brake adjustment
473
The automatic slack adjuster automatically makes a brake adjustment when
The brakes are released
474
The advantage that air disc brake configuration provide over cam operated drum brake configuration is that they
Are not prone to brake fade
475
The caliper of an air disc brake must be able to slide on it's mounting pins so that the
Outboard brake pad contacts the brake rotor
476
The most significant difference tween a pre-CMVSS 121 trailer and a CMVSS 121 trailer is that:
Pre-CMVSS 121 trailers are equipped with air-applied parking and emergency brakes
477
The function of the trailer service line is to
Carry service air pressure from tractor to the trailer
478
One of the functions of the trailer supply line is to
Carry supply air to charge the trailer reservoirs
479
The one-way check valve in the relay emergency valve on a pre-CMVSS 121 trailer prevents
Trailer reservoir pressure from falling I air pressure falls in the trailer supply line
480
One way of releasing the brakes after an emergency brake application on a pre-CMVSS 121 trailer is to
Drain the trailer air reservoir
481
One safety precaution you must observe when parking a pre-CMVSS 121 trailer is
The trailer wheels must be blocked
482
Loss of air pressure in trailer supply line on a CMVSS 121 trailer results in
Applying the trailer spring brakes
483
When charging a CMVSS121 trailer equipped with SR 5 trailer spring brake control valve, the trailer :
Spring brakes release before the trailer air reservoirs are charged
484
In order for a towing trailer to be towed as a single unit , the
Shut off valves in the service and supply lines must be closed
485
The component on a towing trailer that vents the supply line to the towed trailer is
The quick release valve
486
The term cracking pressure refers to the
Pressure required to overcome internal friction in an air brake valve
487
The advantage of a pilot relay valve over a standard relay valve is that it
Has no difference between incoming signal pressure am delivery pressure
488
The delivery pressure from the pilot relay valve on a towing trailer is sent to the
Service line to the towed trailer and the service relay valve
489
The purpose of the spring acting on the upper surface of the pilot relay valve is to
Reduce the time required to apply the trailer brakes
490
The function of the pressure protection valve installed in the supply line to the converter dolly air reservoir is to
Ensure that dolly parking/emergency brakes release before the dolly reservoir is charged
491
The one way check valve in the pressure protection valve on a converter dolly prevents
Reservoir air pressure from falling if dolly supply line pressure is lost
492
The trailer release valve is installed on a converter dolly to
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
The pilot relay valve on the converter dolly relays
Service air pressure to the relay emergency valve on the dolly and the service line to the following trailer
494
Hammer are selected for size by the
Weight Of the head
495
The screwdriver blade that has an hourglass shape is the
Clutch and is sized by diameter of the blade or tip
496
The punch recommended for removing or installing split or roll pins is the
Roll pin punch
497
Describe how a prick punch or centre punch is selected for it's size
Sized by diameter of the stock
498
The chisel that may be beat suited to clean up square keyways is a
Cape chisel
499
What is the general cutting edge angle of a flat chisel?
60* to 70*
500
Open end wrenches are designed to fit a bolt head
Across the flats of the head
501
Name the wrench beat suited for loosening or tightening nuts on steel lines
A flare nut or line wrench
502
Dowel removers work well with dowels that are broken off at the work surface
False ,a portion of the dowel must be above the work surface
503
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
False , a split puller is used to Accra bearings on a shaft
504
When using a hacksaw , the recommended number Of teeth that should be on the material is
No less than two
505
The direction the teeth on an adjustable frame hacksaw blade should face when mounts in an adjustable frame is
Forward
506
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
Scorer
507
What distinguishes a safe edge file?
Has no teeth on the edge
508
List four angles of importance and the amounts of each, on the sharpened portion of a drill bit
Cutting edge or point angle 59*
Included angle is 118*
Lip clearance angle is 12* to 15*
Dead centre angle is 120* to130*
509
The direction reamers must be rotated when going into the hole and coming back out of the hole are
Going in clockwise
| Coming out clockwise
510
List three standard threads taps in the order they should be used
Taper
Plug
Bottoming
511
The tap best suited to tap a tapered hole for sealing of pressure would be a
National Pipe Thread (NPT) tap
512
When performing a double flare on a piece of tubing :
Install the tubing so it protrudes the height of the shoulder of the adapter
513
How should the rest of a floor or bench grinder be positioned
As close to the stone as possible
514
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 ?
True
515
When installing a heli-coil in a hole , the tap in the kit :
Is a special tap for each particular coil
516
A carbon steel drill bit should be rotated at what speed compares to a high-speed steel drill bit ?
One half the speed of high-speed steel
517
What is the purpose of the paper on the side of grinding stone ?
Protects the stone , contains information about the stone size and speed
518
Combination pliers must be used to remove spring hose clamps
False
519
Googles are worn when using oxyacetylene equipment to protect the eyes from
Light
Heat
Sparks and slag
520
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 ?
Neither technicians
521
To check for leaks in oxyacetylene equipment , you should use
Approved leak detection solution
522
Of grease is exposed to pure oxygen , the grease can explode :
Whit out ignition
523
When using oxygen from a cylinder , you should open the valve :
Fully
524
Fusible plugs in acetylene cylinders are located
In the too , bottom and neck of the cylinder
| In the valve of the cylinder
525
Acetylene should only be drawn from an acetylene cylinder when the cylinder is
Upright
526
The specific gravity for propane vapour is
1.55
527
When liquid propane is released to the atmosphere , it
Changes to vapour and accumulates in low areas
528
The colour of an oxygen hose used with oxyacetylene equipment is
Green
529
The colour of an acetylene hose with oxyacetylene equipment is
Red
530
Check valves used with oxyacetylene equipment are installed in
The oxygen hose
| The acetylene hose
531
When you are finished using oxyacetylene equipment , the oxygen an acetylene should be shut off at the
Cylinders , pressures bled off and the regulators should be backed out to the free position
532
The most suitable flame to use when heating with oxyacetylene equipment is
A neutral flame
533
When you purge oxyacetylene equipment prior to lighting the torch , you adjust the acetylene regulator to
5 psi
534
Of a backfire occurs when using an oxyacetylene hearing tip , it may be caused by
Both gases set too low
535
The material that can be easily cut using an oxyacetylene touch with a cutting attachment is
Carbon steel
536
When an oxyacetylene torch is used for cutting , the torch is
Inclined more for thin material
537
What standards must a full body harness meet if manufactured on or after July 1 2009?
CSA
538
How often must your inspect your fall arrest equipment ?
Before use on each shift
539
What is the minimum distance a ladder must protrude above the intended landing point?
1m (3ft)
540
What is the safety factor for scaffold systems ?
Four times the load that may be imposed on it
541
At what height must an employer have a guardrail erected for a temporary work area?
3m (10ft)
542
When conducting a hazard assessment relates to lifting and handling a load, your employer must consider the
Weight , size and shape of the load
543
What is not an example of a recorded lifting technique ?
Lift no higher than eye level
544
What is the goal of proper lifting technique ?
To eliminate loading stresses on the soft tissue of your lower back
545
How is safe working load (SWL) defined ?
Breaking strength divided by the safety factor
546
What does the term shock loading mean when applied to rigging equipment ?
The along is exposed to stress by having the load suddenly started or sroppedb
547
What rigging factor of safety is to be used when lifting and transporting workers?
10:1
548
How often must rigging be inspected ?
At the beginning of each work shift
549
What is recommended when attaching the hook to an eyebolt ?
Always use a shackle when attaching the hook to a load
550
What is the recommended sling angle when rigging a load ?
The sling angle must never be less than 60*
551
Which of the following is not a method of protecting a conductor from corrosion ?
Flux
552
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?
Both A and B technicians
553
All wiring harness connectors have:
Locking mechanism
Mating guides
Removable pins and sockets
554
The purpose of a ..... ...... Is to pass electrical current from one set of wires to another .
Conductor connector
555
..... ..... must are the large current flows required to start a high compression Diesel engine
Cranking circuits
556
........ ....... on heavy equipment is used to transfer visual, audio or digital information
Communication wiring
557
To open a wiring harness that is taped , a ....... ....... can be used without damaging the conductor.
Seam ripper
558
Always install hold-down brackets, clamps and wire ties to prevent wiring harness vibration or movement that could cause ....
Chafing
559
If conductor wires are not damaged , but the conductor insulation is damaged , it can be repaired by using .... ..... .....
Heat shrink tubing
560
An approved method of repairing copper conductors is ..... ......
Crimp splicing
561
All electrical schematics are drawn in a ...... condition
De-energized
562
The components of an electrical switch that conducts the electrical current are called ......
Contacts
563
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 ?
Technician B
564
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?
Technician A and B
565
When a fuse in an electrical lighting circuit overheats and burns out quickly , the probable cause is :
A ground fault
566
When two or more electrical lighting circuits operate abnormally at the same time , the probable cause is
A short
567
When one lamp in an electrical lighting circuit burns dimly when compared to the other Lamps in the same circuit the probable cause is:
An unwanted high resistance
568
When current stops flowing in part of an electrical lighting circuit , the probable cause is :
An open circuit
569
When testing a relay a cross the coil you receive a reading of OL what is the most likely cause of failure?
An open circuit
570
What are the four factors a technician must consider when repairing broken conductors or replacing damaged conductors ?
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
The number of millimetres in one centimetre is
Ten
572
The term witch beat describes the tendency of a body to remain in motion is
Inertia
573
Force may be best described as a
Push or pull
574
Area of a circle is calculated by multiplying the
Constant 0.7854 by the radius square
575
Convert 21/64 to a decimal rounded to three decal places
0.328
576
Convert 0.484375 to an exact fraction
31/64
577
Convert 0.280 to a practical fraction to the nearest 1/32
9/32
578
Calipers can be used to measure
Inside or outside diameters
579
A stepped feeler gauge for measuring a clear emcee of 0.015 inch will be marked on the blade
0.014 inch to 0.016
580
A typical telescoping gauge set has a typical range of
5/16 inch to 6 inches
581
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
0.378 inch
582
A standard outside imperial micrometer measures 5.671 inch . The divisions showing on the scale would be
6 large 2 small and 21 on the thimble
583
An inside micrometer with 2 late divisions , 3 small divisions and 15 on the thimble is measuring :
2.290 inch
584
An inside imperial micrometer measuring 4.678 inch will have which of the following scale readings showing ?
1 large 3 small 3 on the thimble
585
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
0.8976 inch
586
A depth micrometer will measure protrusion accurately
False ,erasures a recession
587
A dial indicator plunger should be set to move
At mid range of travel
588
Precision measuring tools should be stored
In a special drawer or cabinet
589
Torque wrenches measure
Rotation force
590
If a force of 220N was applied on a wrench which is 600 mm long , the resulting torque would be
132N • m
591
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
50
592
List three functions of a vehicle frame
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
The point at which the maximum force is concentrated on a frame is called the
Maximum bending moment
594
A ladder type frame is made up of
Crossmembers
| Parallel frame rails
595
The function of frame crossmembers is to
Provide strength and rigidity to the frame assembly
596
Which one of the following is not a common frame rail shape
Trapezoid
597
The surface between the flanges of an I-beam frame rail is called the
Web
598
What is the function of a gusset that is attached to a frame crossmember ?
Provide resistance to the frame weaving
599
The size and shape of the frame components affect the strength of the frame ?
True
600
Define the term yield strength as it applies to the strength of frame materials
The amount of stress that the material can withstand before becoming permanently deformed
601
Which of the following frame materials should have the highest yield strength?
Heat treated alloy steel
602
The term section modulus refers to the strength of frame components based on
Height
Width
Thickness
Shape
603
A frame with a high resisting bending moment RBM has less strength than a frame with low RBM
False , the greater the RBM the greater the strength of the frame
604
List four functions of a vehicle suspension system
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
The term unsprung weight refers to the weight of the vehicle and it's load
False , the combined weight of the components below the connection point is called unsprung weight because it is located below the suspension system
606
The suspension system must hold the axles in alignment with the frame . This means that the:
Wheels are held parallel to the frame rails
607
Three of the most common types of energy-absorbing devices used in suspension systems are
Leaf springs
Rubber Cushing
Air springs
608
The energy-absorbing device of a is pension system is released when it rebounds .
True
609
Solid mount suspension systems are beat suited to applications that:
Operate on rugged terrain
610
Equalizer beams reduce the effect of chick loads to the vehicle frame by
50%
611
Axles are stabilized against braking and acceleration force by ....
Longitudinal torque rods
612
The function of transverse torque rods is to ....
Provide improved side to side stability by distributing side loads more evenly across the entire length of the axle
613
Progressive lead springs provide a low spring rate when the vehicle is unloaded and a high spring rate under load
True
614
Auxiliary springs help to support the vehicle when it is
Loaded
615
Spring shackles accommodate changes in the spring length as the suspension jounces and rebounds
True
616
The main function of a shock absorber is to....
Dampen spring oscillation
617
The function of vertical drive pins on a rubber cushion type suspension is to.....
Allow the saddles to move up and down as the load cushions deflects , thus maintaining alignment of the saddles with the frame rails
618
An advantage that air spring suspensions have over other suspension types is that they provide superior
Ride quality
619
State the function of the pressure protection valve in an air spring suspension
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
The ride height control valve supplies air to the air spring when:
Additional load is added to the vehicle
621
The function p the two way control valve and dump valves is to
Allow the driver to exhaust the air springs so that the suspension will lower when connecting or disconnecting a trailer
622
All bearings are designated to provide support to moving parts , keep parts in alignment , increase friction an provide a replaceable wear surface
False , bearings are designed to decrease friction
623
Axial loads may be offset by
Needle bearings
624
Crush is a term used to describe the
Force on a preloaded bearing
625
Choose the answer that does not describe an anti friction bearing
High contact area between moving parts
626
Plain roller bearings are designed to support radial loads only
True
627
Needle bearings are
Most often used where space is limited
628
Choose the term that beat describes static seals
They seal between non moving parts
629
O-rings may be replaced with silicone of needed
False , silicone is only used used a a sealant in place of a gasket
630
Choose from the following the sentence that best describes gaskets
Metal gaskets can usually withstand higher pressures and temp
631
Silicone may be used with cork or paper gaskets
False , so not use silicone with cork or paper gaskets as the gasket may slip out or become too thick
632
Choose the term that beat describes face seals
There is a little or no wear on the moving shaft
633
Choose the answer that best relates to preload
Preload is set by shims , spacers or a threaded ring
634
Brinelling is
Indentation from shock loading
635
With regard to bearings, arcing is a term used to describe :
Marks on the bearing due to discharges of electricity within the bearing
636
List three contributing factors that lead to abnormal bearing fatigue
Speeds that are more than bearing rating is
Shock loads
Vibration
637
Bearing failure is most often attributed to
Contamination ingested from external sources
638
When removing bearing from a shaft using the non destructive method
Ensure the bearing is supported as close to the shaft as possible
639
Explain the procedure to Han pack a bearing
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
When heating bearings , so not use
Flame
641
Bearings should not be heated above
250F (120*C)
642
Fifth wheel couplings are used to connect a semi-trailer to
A tractor
Converter dolly
The lead trailer of a B train combination
643
The fifth wheel component that provides the bearing surfaces for the weight o the front of the semi-trailer is the
Top plate
644
The purpose of the coupling jaws in a fifth wheel is to engage and secure the trailer
True
645
Fifth wheel assemblies are rated on four considerations. What are they?
Towed vehicle weight TVW
Maximum expected drawbar load
Vertical load to be carried by the fifth wheel
Type of operation
646
Four advantages of sliding over stationary fifth wheels are
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
Which of the following fifth wheels is the most commonly used fifth wheel?
Semi-oscillating type
648
Pintle hooks designed to remove the clearance between the hook and the drawbar eye are called ...
No slack pintle hooks
649
The function of the safety restraint on a trailer unit coupled with a pintle hitch is to .....
Ensure that the trailer remains attached to the towing unit in the event of a trailer hitch separation
650
List four fault that can be identified by visually inspecting a fifth wheel
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
Excessive clear wine between the fifth wheel jaws am the lock tester kingpin is a result of ...
Improper jaw adjustment
| Excessive jaw wear
652
The amount of wear in fifth wheel oscillating pins an bushings can be checked by
Barring the top plate up and down as well as back and forth
653
A distorted or cracked fifth wheel too plates at be straightened or welded before it can be rebuilt
False . A top plate must not be welded or straightened because it will weaken
654
The contact surface of the fifth wheel too plate is lubricates with
Water resistant lithium based grease
655
What two fifth wheel components should be lubricates with a light lubricating oil?
Cam track path and pivot point
| Rack and slide path on sliding fifth wheels
656
A trailer kingpin must be replaced if it is bent more than 1*
True
657
A trailer king pin must be replaced if it's diameter is worn more than:
3mm 0.125in
658
Before backing a tractor into a semitrailer you must:
Inspect the fight wheel for damage
Ensure the slider plungers are engaged
Check that the lick jaws are open
659
Trailer air and electrical connections can be made after the trailer is securely coupled to the fifth wheel
False ,the connection must be done before coupling in order to set the trailer brakes
660
Why test must be performed after the trailer is coupled to the fifth wheel?
A pull test must be performed by gently pulling against the trailer parking brakes
661
The first step in uncoupling a tractor semi trailer combination is to
Position the unit on dorm , level ground
662
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.
True
663
Two common types of landing gear are
Drop leg
| Gear operated landing gear
664
The condition where gear set input speed is reduced and torque is decreased. Is called:
An underdrive
665
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....
3.77:1
| An under drive or gear reduction
666
When a gear-operated landing gear is operated in low speed , crankshaft speed is .... Though gears before being applied to the lift screw
Reduced
667
During high speed operation, the gear box in the landing gear provides a gear ratio of 0.62:1. This ratio is an
Overdrive
668
Lifting and lowering the trailer must be done with the landing get in hight speed
False, lifting and lowering must be some in low speed to prevent damage to the gear set
669
If the landing gear will not stay in hear while cranking , a possible cause could be:
Faulty shift ball and spring
670
The gears in the landing gear are lubricates with
Grease
671
One possible cause for frame sideway is :
An accident , collision or rollover
672
The difference between frame sag an bow is ....
One is bent up and the other is bent down
673
Corrosion of frame material can be a result of:
Climatic conditions(rain, snow, ambient temp)
Exposure to certain cargo materials
Contact between two dissimilar metals such as aluminum and steel
674
Four factors that accelerate frame stress and therefore the possibility of frame cracking are:
Overloading
Unevenly distributed load
Operating on rough terrain
Loose or worn crossmember attaching bolts
675
Improper frame alignment can be a source of tracking and alignment problems?
True
676
When marking a frame rail, you should use :
Chalk or soapstone
677
Two reasons for using hardened washers in bolted frame connections are:
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
One advantage of using Huck fasteners for attaching frame components is they:
Do not allow flexing of frame components
679
Heat treated frame rails must be heated in order to straighten them?
False
680
A vehicle equipped with a leaf spring suspension is leaning to one side . A possible cause of this fault is:
Broken leaf springs
681
List three possible causes for an air spring suspension to bottom
```
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
State the procedure for checking shock absorber operation
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
It is acceptable to replace a single leaf in a leaf spring assembly if an individual leaf is damaged
False
684
A compound like Alumilastic is used on the surfaces of aluminum suspension components that contact other metals because it :
Prevents corrosion reactions
685
The trust from a properly aligned drive axle will act ....
Along the frame centreline
686
Equalizer beam end bushing clearance can be checked by ....
Jacking the beam end up with a hydraulic jack and checking beam end movement
687
The beat way to remove equalizer beam end and centre bushings is to:
Use appropriate presses and pullers
688
The difference between bar pin and other types of equalizer beam end bushings is ...
They provide a point of axle alignment adjustment
689
Rubber load cushions have a due omelet number that indicates ...
The hardness of the rubber cushion which determines it's load capacity
690
Drivers must drain air reservoirs at least daily in order to ensure that the:
Moisture and contamination in the reservoir a will be removed
691
The driver will have difficulty connecting a tractor to a trailer if the ride height on the air spring suspension is adjusted too high .
True
692
When the load is removed from a vehicle equipped with an air spring suspension, the ride height control valve will:
Exhaust air from the air springs until the correct ride height is reached
693
Adjusting the ride height on an air spring suspension that is equipped with an adjustable valve mounting is accomplished by making a linkage adjustment
False
694
Breakdown maintenance is a system of maintaining a machine whereby components are replaced on a regularly scheduled service interval.?
False .breakdown maintenance refers to the policy of running a component machine until something breaks . At that time replacement occurs
695
Identify three hidden costs that can occur of a system of breakdown maintenance is followed :
```
Unexpected equipment downtime
Secondary component damage
Reduced equipment life
Higher overall costs
High operator and technician turnover
```
696
Component failure and damage can be classes as primary and secondary . Explain what effect secondary damage may have on a machine
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
Preventive and predictive maintenance systems attempt to reuse the number of unexpected breakdowns . Identify five purposes of a predictive maintenance systems
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
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:
Computers ages maintenance system
Parts department card system
Service department card system
Accounting department card system
699
Off road machines are often shit down for maintenance after so many hours of operation ?
True
700
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
Oil analysis and oil filter contamination
Vibration analysis
Heat detection
Component life history
701
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
```
Increased productivity
Reduced maintenance costs
Reduced emergency and breakdown time
Reduced secondary damage
Aids in scheduled maintenance
```
702
A regularly scheduled oil analysis program does not help you predict component problems, long before failure occurs .
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
A careful, conscientious , observant and alert service technician is required to make a success of any preventive maintenance program
True
704
The main advantage of using a deck trailer to carry cargo is ....
Easy access for loading and unloading
705
A highboy trailer has the deck located :
Above the tractor /trailer wheels and suspension components
706
Two advantages of a lowboy deck trailer are:
Higher loads can be carried
| The centre of gravity of the loads is lower, increasing stability
707
Trailer that protect the load from environmental conditions are called
Van trailers
708
Temperature controlled trailers
Keep the cargo at a constant temp
709
Tank type trailers are designed to carry liquid cargo only?
False , can also carry granular , dry type materials
710
Trailers that can be lengthened or shortened to accommodate loads of varying length are called ....
Extendable
711
Vehicle ground pressure is a measure of:
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
What type of coupling device is used to connect a pony trailer to a body loaded truck ?
Pintle hook
713
How many points of articulation are there on a body loaded truck and pony trailer ?
1
714
A tractor and single semitrailer are connected using a ....coupling an has ....point of articulation
Fifth wheel
| One
715
The unit that takes some of the weight off of the tractor when oversized loads are being hauled is called a:
Jeep
716
On a A train combination with two semitrailers , the following semitrailer is connected to the lead trailer by a :
Converter dolly
717
B train combinations are more stable during operation than A trains because ....
The following semitrailer is connected to the lead trailer by a fifth wheel and kingpin connection that provides only one point of articulation
718
The device that connects the following trailer to the lead trailer by two or more pintle hooks, couplers and drawbars is called a :
C train dolly
719
An axle that causes the wheels to track parallel to the trailer frame rails at all times is called a .....
Fixed axle
720
Steering axles are used on some trailer units to....
Prevent tire scuffing when the tractor/trailer combination negotiates a right turn
721
Name two basic styles of wheels used on heavy equipment :
Spoke wheels
| Disc wheels
722
Explain the main differences between the two wheel styles spoke and disc
Spoke wheels are supported by a bearings and can be considerately as a type of hub
Disc wheels are fastened to a hub
723
Identify the two types of disc wheels in term of how they are piloted
Stud piloted-centred by the studs and nuts
| Hub piloted-centred by the machined hub pads
724
When dual tires and wheels or rims are used , a spacer must be also be used. Explain the purpose of the spacer:
The spacer ensures that the two tires are separated sufficiently to prevent contact during normal operation
725
It is permissible to use any style of wheel nut when mounting stud piloted wheels ?
False.only use cone/ball type tapered wheels nuts
726
It is permissible to use one stud piloted wheel and one hub piloted wheels as a dual wheel set?
False. Only use a set of stud piloted OR a set of hub piloted wheels as a dual wheel set
727
Identify two main types of tires, in terms of the air retention methods.
Tube type
| Tubeless type
728
Tire tread designs can be of two general styles . Name and explain when those styles are typically used
Rib-non-traction , steering on-highway use , trailer
| Lug or block-traction application
729
Explain the two major types of tire construction in common use
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
Tires are matched by checking the size on the side wall of the tires
False . Tires must be measured for circumference and diameter and be matched whit in allowable limits
731
Identify the equipment that could be used to measure tires in the process of matching them together
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
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
False. Ideally both axles tire sets are identically matched
733
Identify the two main tire inflation problems. Of these two explain which is worse and why
Under inflated -worse heat can destroy tire
| Over inflated -faster tire wear
734
As an apprentice , explain what you could do to prevent personal injury when working around tires/wheels and rims
Get training
735
Explain what visual checks you should do before moving any tire assembly
Visually inspect the tire/wheel /rim for signs of overheating, damage, cracks and mismatched parts
736
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
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
It is permissible to weld or braze I a steel wheel?
False. Do not weld , braze, rework or heat a wheel or wheel components.
738
Describe the equipment you would use to safely inflate a tire and wheel or rim assembly
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
It is permissible to mix wheel and rim side rings and lock rings ?
False . Never mix wheel/rim components . Always match the parts together
740
Axle wheel hubs generally use a set of two tapered bearings. These bearings do not require adjustment ?
False bearings operating as sets must be adjusted
741
Wheel bearings are only lubricated by grease
False. Oil is often used
742
All wheels studs have right hand threads
False . Some have left hand threads
743
Identify the two general types of wheel balance problems
Static -centralized heavy spot across a thread or rim
| Dynamic- heavy spot on a side of a tire thread or wheel rim
744
Which tire imbalance is identified by the word bounce ?
Static imbalance
745
Which tire imbalance is identified by the word shimmy?
Dynamic imbalance
746
Wheel weights used for balancing tire assemblies must be a specific shape and contour
True
747
Cracks in steel wheels can be welded and the wheel can then be returned to service
False . Never weld a cracked wheel
748
To prevent internal tire and wheel/rim damage air lines should be free of water and oil
True
749
Wheel or rim chording is used to describe flat spots on the wheel/rim edges
True
750
Long tire life is only obtained by a joint effort between the operator and the service technician
True
