MAKERERE
UNIVERSITY
COLLEGE OF ENGINEERING, DESIGN, ART AND
TECHNOLOGY
SCHOOL OF ENGINEERING
DEPARTMENT OF MECHANICAL ENGINEERING
INDUSTRIAL TRAINING REPORT
AT
DANIEL COMBONI VOCATIONAL INSTITUTE
NAME:
OKELLO JOB LAZARUS
REG. NO. 14/U/1050
STUDENT NO. 214000258
A REPORT SUBMITTED TO MAKERERE UNIVERSITY, DEPARTMENT OF
MECHANICAL ENGINEERING IN PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR THE AWARD OF THE DEGREE OF BACHELOR OF SCIENCE IN MECHANICAL
ENGINEERING OF MAKERERE UNIVERSITY
AUGUST, 2017
DECLARATION
I OKELLO JOB LAZARUS, do declare to the best of my knowledge, that this report is
originally mine; it is a true record of the work I undertook during my industrial training at Daniel
Comboni Vocational Institute and has never been submitted for the award of the Degree of
Bachelor of Science in Mechanical Engineering or any other academic qualification to Makerere
University or any other University or academic institution of higher learning.
Signature…………………………
Date……..………….………
OKELLO JOB LAZARUS
i
APPROVAL
This industrial training report was submitted to Makerere University, Department of Mechanical
Engineering after the approval of the following:
Signature…………………………………
Date….……..…….………
Mr. RACHKARA PHILIP
TRAINING SUPERVISOR
Signature…………………………………
Date…….……..…..………
Mr. OCHEN RICHARD
PRINCIPAL, DANIEL COMBONI VOCATIONAL INSTITUTE
Signature…………………………………
Date….……..…….………
Dr. MICHAEL LUBWAMA
ACADEMIC SUPERVISOR
DEPARTMENT OF MECHANICAL ENGINEERING,
MAKERERE UNIVERSITY
ii
DEDICATION
This report is dedicated to my precious mother, Ms. Florence Auma, who pays the greatest price
for my studies. May the ever-good Lord reward you abundantly dearest mum.
iii
ABSTRACT
Industrial training is one of the requirements for the award of the Degree of Bachelor of Science
in Mechanical Engineering of Makerere University. As such, students are required to write and
submit reports at the end of the training.
This report is the record of what I personally did during my industrial training at Daniel
Comboni Vocational Institute (DCVI) from June to August, 2017.
It consists of four chapters which altogether explain the objectives of industrial training, entail
background information about the institute, various activities carried out at the institute, general
overview of Motor Vehicle Technology, the hands-on activities which I took part in and the
skills acquired, challenges faced, recommendations and conclusion.
Chapter one covers the objectives of industrial training, gives the background information about
DCVI including its core values, mission, vision, products and services provided and clientele.
Chapter two presents the general overview of Motor Vehicle Technology.
Chapter three entails all the practical activities undertaken at the workshop giving for each
activity, the different tools and equipment used, technical procedures followed, common faults,
their causes and remedies.
Chapter four covers the skills acquired, challenges faced, recommendations and conclusion.
iv
ACKNOWLEDGEMENTS
First and foremost, I express my sincere gratitude to God for His unconditional love, guidance
and protection; and for making the training a success. It is entirely by His grace that I have reached
this far in life in general and the academic journey in particular. Praise, glory and honor be to Him!
I extend my heartfelt gratitude to the management of DCVI for granting me the valuable
opportunity to train at their institution. In particular, my appreciation goes to the Principal Mr.
Ochen Richard, for admitting me and my training supervisor, Mr. Rachkara Philip for his
precious guidance and support rendered to me throughout the training.
I also thank all the staff of the DCVI especially those of the MVT Department for the great ideas
and thoughts shared with me during the entire training period and for their hospitality and
cooperation that made it inevitable for me to acquire the much-desired practical knowledge and
skills in the field of Mechanical Engineering.
Special thanks also go to the Mechanical Engineering Department of Makerere University and
the University Administration at large for availing me with this study time so as to apply the
theoretical skills learnt in class into real life problem-solving situations and understanding of the
Mechanical Engineering profession at large.
With great honor and in a special way, I thank my University supervisor Dr. Michael Lubwama
for his tremendous support and guidance rendered to me both during and after the training.
Sincere gratitude is also expressed to my fellow trainees- Otim Deogracious, Alega Samuel,
Ntambi John Mary, Ngolobe Peter and Anyango Beatrice, with whom we shared valuable
ideas; for their support, company and continued team work exhibited during the entire industrial
training period.
I am immensely grateful to the Chancellor of Gulu Archdiocese Rev. Fr. Martin Agwee for
recommending me for internship opportunity at this prominent institution.
I am greatly indebted to Uganda’s Assistant Ambassador to Japan, H.E Nyeko Michael Ocula
for the critical role he played in securing internship place for me at this prestigious institution.
Heartfelt appreciation is also expressed to my Spiritual mother Ms. Elizabeth Diana Babirye
for providing the money for printing this internship report and for always being there for me.
Special appreciation also goes to Dorcus Nduhukire for typesetting and designing the layout of
this report.
Most importantly, heartfelt thanks and love are expressed, to my mother Ms. Florence Auma for
her tremendous assistance, support, love, encouragement and inspiration, and for paying the
greatest price for my education. You are one of a kind and the greatest of all mothers.
Finally, to all those who have supported my academic journey yet whose names are not
mentioned here, I am truly grateful and very much appreciate all your contributions. May the
ever-good Lord immensely reward you all!
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TABLE OF CONTENTS
DECLARATION ........................................................................................................................................... i
APPROVAL ................................................................................................................................................. ii
DEDICATION ............................................................................................................................................. iii
ABSTRACT................................................................................................................................................. iv
ACKNOWLEDGEMENTS .......................................................................................................................... v
TABLE OF CONTENTS ............................................................................................................................. vi
LIST OF TABLES ....................................................................................................................................... xi
LIST OF FIGURES .................................................................................................................................... xii
LIST OF ACRONYMS USED .................................................................................................................. xiv
CHAPTER ONE: GENERAL INTRODUCTION .................................................................................. 1
Background ............................................................................................................................................. 1
Industrial training objectives ................................................................................................................... 1
General objectives ................................................................................................................................ 1
Specific objectives ............................................................................................................................... 1
Background of Daniel Comboni Vocational Institute............................................................................. 1
Location of DCVI ................................................................................................................................ 2
Address of DCVI ................................................................................................................................. 2
Mission statement of DCVI ................................................................................................................. 2
Vision statement of DCVI.................................................................................................................... 2
Objectives of DCVI ............................................................................................................................. 2
Services offered by DCVI .................................................................................................................... 3
Clientele of DCVI ................................................................................................................................ 3
vi
Departments at DCVI .......................................................................................................................... 3
The organizational structure of DCVI ................................................................................................. 4
The MVT Department ........................................................................................................................ 6
The Motor Vehicle Workshop ........................................................................................................... 6
CHAPTER TWO: MOTOR VEHICLE TECHNOLOGY ..................................................................... 7
Introduction ............................................................................................................................................. 7
Vehicle Systems ...................................................................................................................................... 7
The Transmission System .................................................................................................................... 7
The Electrical System .......................................................................................................................... 8
The Fuel System .................................................................................................................................. 9
The Braking System ........................................................................................................................... 10
The Suspension System ..................................................................................................................... 11
The Steering System .......................................................................................................................... 14
The Intake and Exhaust Systems ....................................................................................................... 15
CHAPTER THREE: HANDS-ON ACTIVITIES CARRIED OUT ..................................................... 18
Introduction ........................................................................................................................................... 18
Diagnosis and correction of failure of a car battery .............................................................................. 18
Common faults of the car battery, their causes and remedies ............................................................ 18
Fault found with the battery ............................................................................................................... 19
Tools and equipment used to recharge the battery ............................................................................. 20
Technical procedures followed .......................................................................................................... 20
Replacement of water pump of a Cesspool truck.................................................................................. 20
vii
Common faults with water pumps, their causes and remedies .......................................................... 21
Fault found with the water pump ....................................................................................................... 23
Tools and equipment used to replace the pump ................................................................................. 24
Technical procedures followed ........................................................................................................... 24
Replacement of hydraulic oil of a FAW truck ...................................................................................... 25
Dangers involved in working with hydraulic fluids ........................................................................... 25
Safety precautions when dealing with hydraulic fluids ..................................................................... 26
Common faults with the hydraulic system ......................................................................................... 27
Solutions to the common faults .......................................................................................................... 27
Recommendations on hydraulic systems ........................................................................................... 29
Faults found with the hydraulic oil .................................................................................................... 29
Tools and equipment used to replace the hydraulic oil ...................................................................... 29
Technical procedures followed .......................................................................................................... 29
Replacement of leaf springs of a FAW truck ........................................................................................ 30
Functions of the suspension of the vehicle ........................................................................................ 31
The purpose of leaf springs ................................................................................................................ 31
Maintenance of leaf springs ............................................................................................................... 31
Fault found with the leaf springs........................................................................................................ 31
Safety precautions while replacing leaf springs ................................................................................. 31
Tools and equipment used to replace the leaf springs ........................................................................ 32
Technical procedures followed to replace the leaf springs ................................................................ 32
Replacement of a tire of a garbage truck .............................................................................................. 34
Common tire problems and their solutions ........................................................................................ 34
Minimizing tire problems................................................................................................................... 34
viii
Fault found with the tire ..................................................................................................................... 35
Safety procedures while replacing tires.............................................................................................. 35
Tools and equipment used to replace the tire ..................................................................................... 36
Technical procedures followed .......................................................................................................... 36
Troubleshooting starter motor of a Toyota Pick-up .............................................................................. 37
Common symptoms of a failing or bad Starter, their causes and remedies........................................ 37
Safety procedures while troubleshooting a starter motor ................................................................... 38
Tools and equipment used.................................................................................................................. 39
Technical procedures followed .......................................................................................................... 39
Testing the starter ............................................................................................................................... 39
Adjusting the clutch of a garbage truck ................................................................................................ 40
Common faults with the clutch system, their causes and remedies ................................................... 40
Faults found with the clutch system ................................................................................................... 42
Tools and equipment used to adjust the clutch ................................................................................... 43
Technical procedures followed .......................................................................................................... 43
Panel beating a Pajero Shogun .............................................................................................................. 45
Reasons for the operation.................................................................................................................... 45
Tools and equipment used.................................................................................................................. 45
Safety precautions for the operation................................................................................................... 45
Technical procedures followed .......................................................................................................... 45
CHAPTER FOUR: SKILLS ACQUIRED, CHALLENGES FACED RECOMMENDATIONS AND
CONCLUSION ......................................................................................................................................... 48
Introduction ........................................................................................................................................... 48
ix
Experience gained/achievements from the training .............................................................................. 48
Challenges faced during the training..................................................................................................... 48
Recommendations ................................................................................................................................. 50
Conclusion ............................................................................................................................................ 50
REFERENCES .......................................................................................................................................... 51
x
LIST OF TABLES
Table 1: DCVI Departments and their mandates ............................................................................ 4
Table 2: Water pump troubleshooting chart ................................................................................. 21
Table 3: Clutch diagnosis/troubleshooting chart .......................................................................... 41
xi
LIST OF FIGURES
Figure 1: Organizational Structure of DCVI................................................................................................. 5
Figure 2: Organizational Structure of the MVT Department ........................................................................ 6
Figure 3: The Transmission System .............................................................................................................. 7
Figure 4: The Electrical System .................................................................................................................... 8
Figure 5: The Fuel System .......................................................................................................................... 10
Figure 6: The Braking System .................................................................................................................... 11
Figure 7: The Suspension System ............................................................................................................... 12
Figure 8: The Front Suspension System ..................................................................................................... 13
Figure 9: The Rear Suspension System ...................................................................................................... 14
Figure 10: The Steering System .................................................................................................................. 15
Figure 11: The Intake System ..................................................................................................................... 16
Figure 12: The Exhaust System .................................................................................................................. 17
Figure 13: Recharging the battery ............................................................................................................... 20
Figure 14: The removed water pump .......................................................................................................... 24
Figure 15: The unit that houses the water pump ......................................................................................... 25
Figure 16: Draining the hydraulic oil .......................................................................................................... 30
Figure 17: Removing the broken leaf springs ............................................................................................. 33
Figure 18: The broken leaf springs that were removed ............................................................................... 33
Figure 19: Removing the tire ...................................................................................................................... 37
Figure 20: Testing the voltage being received by the starter ...................................................................... 39
Figure 21: The opened clutch system ......................................................................................................... 44
xii
Figure 22: The removed pressure and clutch plates .................................................................................... 44
Figure 23: Sanding using smooth sand paper 500....................................................................................... 47
Figure 24: Covering the parts that were not supposed to be sprayed .......................................................... 47
xiii
LIST OF ACRONYMS USED
ABS
Antilock Brake System
AC
Alternating Current
BCP
Building & Concrete Practice
BOG
Board of Governors
C&J
Carpentry & Joinery
DCVI
Daniel Comboni Vocational Institute
DIT
Directorate of Industrial Training
E.I
Electrical Installation
EU
European Union
Fr
Father
H.E
His Excellency
km
Kilometer
kpa
kilopascal
MECP
Mechanical Engineering Craft Practices
MoE&S
Ministry of Education and Sports
MVT
Motor Vehicle Technology
NEMA
National Environment Management Authority
NGOs
Non-Governmental Organizations
NOA
Non-Asbestos
P.O
Post Office
PPE
Personal Protective Equipment
RD
Road
REG. NO.
Registration Number
Rev
Reverend
STUDENT. NO.
Student Number
UBTEB
Uganda Business & Technical Examinations Board
UPDF
Uganda People’s Defense Forces
xiv
CHAPTER ONE: GENERAL INTRODUCTION
Background
Industrial attachment is an industrial based practical training experience that prepares students
for the tasks they are expected to perform on completion of their training.
Industrial training objectives
The university through its industrial training program aims at achieving a number of objectives
and these include the following;
General objectives
To produce practical oriented graduates that meet the required job-related competences of their
future employers.
To serve as a go-between the University and the various partners who consume services and/or
products of the University.
Specific objectives
To enable students get hands-on experience in real-life situations they are expected to work in
when they graduate.
To provide an opportunity for students to apply the principles and techniques theoretically learnt
into real-life problem-solving situations.
To provide an opportunity for students and academic staff to interact with stakeholders and
potential employers to appreciate industrial situations that will also generate information for
curricula review and improvement.
To develop an understanding of work ethics, employment demands, responsibilities and
opportunities.
To enable students to bridge the gap between the theories studied in class and the practical part
of the theory.
Background of Daniel Comboni Vocational Institute
Daniel Comboni Vocational Institute (DCVI) is a mixed day school with limited accommodation
facilities for students. It was founded in 1995 by the Comboni Missionaries as a private
institution, in line with the government policies and academic directives of the Ministry of
Education and Sports (MoE&S). DCVI was started in response to the needs of the local
population. In spite of the troubles and insecurity at the time, it was hoped that the Institute
would be a tremendous contribution to the local population’s hopes and legitimate aspirations to
1
peace. The Institute aspires and hopes to provide advanced Vocational skills and knowledge to
technicians and craftsmen / women to meet the growing demands for skilled workers in the
public and private sectors, which is a good tool to fight poverty, hunger and neglect.
It is a registered institution and is a centre for Uganda Business & Technical Examinations Board
(UBTEB) and Directorate of Industrial Training (DIT) of the Ministry of Education and Sports.
DCVI offers five courses of two years each leading to the award of National, craft and Advanced
certificates. They are: Motor Vehicle Technology (MVT), Electrical Installation (E.I), Carpentry
& Joinery (C&J), Building and Concrete Practice (BCP) and Mechanical Engineering Craft
Practices (MECP).
Location of DCVI
DCVI is located in Layibi village, Techo parish, Layibi Division, Gulu Municipality on plot
61/95 Daniel Comboni Road, 600m off Juba Road.
Address of DCVI
P.O.BOX, 777 Gulu-Uganda.
Tel: +256-392 799 606
Fax: +256-471 432 827
Email:
Website:
info@combonivocational.ac.ug
www.combonivocational.ac.ug
Mission statement of DCVI
To provide advanced skills and knowledge to technicians and craftsmen and women to meet the
growing demands for skilled workers in both the public and private sectors.
Vision statement of DCVI
Promotion of skill-based training for self-employment.
Objectives of DCVI
To provide technical training so as to create competent craftsmen/women and technicians.
To provide scientific, mathematical and humanitarian foundation to enable students competently
handle the technical aspects of their trades.
2
To create self-reliant citizens thus becoming job creators and not job seekers.
To allow young Ugandans of different religions acquire training and professional knowledge in
the available technical trades.
To equip students with communication skills that facilitates effective knowledge sharing and
transfer.
To make students responsible and conscious of their roles in creating and developing the
Christian society.
Services offered by DCVI
The services are provided via the Production unit. The institute, through the Production unit,
which is made up of all the departments, provides services such as Repair of Customers'
Vehicles, fabrication of metal products such as doors and windows gates, among others, making
of furniture out of timber for customers, Construction of buildings, Electrical Wiring and Repair
of electric motors and generators among others. Other services in the related fields are also
available.
Clientele of DCVI
The clientele of DCVI include among others; the general public, Toyota Gulu, Gulu Archdiocese
institutions, the government of the Republic of Uganda, politicians, schools, hotels, business
entities, Government ministries, mobile service providers and telecommunication companies,
UMEME, Bank of Uganda and all other financial institutions operating within Gulu and
neighboring areas, Non-Governmental Organizations (NGOs) operating within Gulu and
neighboring areas, Tourists, Health centers and hospitals, Security institutions like the UPDF,
Uganda Police, Uganda Prison and many others.
Departments at DCVI
DCVI is made up of five Departments which altogether form the Production Unit, through which
the services of the institution are provided to its clientele. The departments and their respective
mandates are presented in Table 1 below.
3
Table 1: DCVI Departments and their mandates
DEPARTMENT
MANDATE
Mechanical
Responsible for machining works using lathe, milling, grinding, drilling,
Engineering Craft
hydraulic press, and shaping machines, welding and fabrication works, and
Practices
roofing among others: both within and outside the institute.
(MECP)
Carpentry and Joinery Deals in furniture like chairs, tables, doors, door frames, cupboards, wooden
(C&J)
beds, windows and window frames among others.
Building and
Concrete
Practice
(BCP)
Motor Vehicle
Technology
(MVT)
Electrical
Installation
(E.I)
Deals in general building and construction works and construction
materials like cement and bricks among others.
Responsible for maintenance of automobiles and equipment like vehicles,
graders, rollers, tractors, caterpillars among others and general automotive
works.
Electrical installation works, repair and maintenance of electrical appliances
like radios, screens, phones, cameras, refrigerators and others, solar
installation works, motor rewinding and servicing, transformer rewinding
and servicing, and general electrical works both within and outside the
institute.
The organizational structure of DCVI
The institute has a Board of Governors (BOG) which meets regularly on policy issues, reviews
narrative and financial reports from the Institute’s Administration and approves yearly budget.
The Administration is headed by the Director and the Deputy Director and the Personnel
Coordinator. The three officers form the Management Committee; other members of staff in the
Administration include the Financial Assistant, Accountant, two Secretaries, Cashier and Office
Assistant.
In the training area, each trade has a Head of Department; these include MECP, E.I, MVT, C&J
and BCP Departments.
Each of the above departments has teachers and support staff. The list of teachers also includes
part-time teachers for general subjects such as Entrepreneurship and English. Production Units as
4
well have their Heads of Departments and support staff. The above set-up constitutes the whole
team of the work force in DCVI.
The organizational structure of DCVI is as shown in Figure 1 below. During my internship, I
was assigned to the MVT Department which is under the Production Unit together with the other
Departments. A description of the activities carried out in this Department is given in section
of this report.
BOARD OF GOVERNORS
DIRECTOR
MANAGEMENT COMMITTEE
DEPUTY DIRECTOR
HEADS OF TRAINING
DEPARTMENTS
PERSONNEL COODINATOR
FINANCIAL ASSISTANT
EXAMINATIONS
SECRETARY
TEACHERS
SECRETARY
SUPPORT
PRODUCTION
UNITS
SUPPORT STAFF
APPRENCTICE
STUDENTS
ACCOUNTANT
STORE
CASHIER
SUPPORT STAFF
DRIVER
SECURITY
KITCHEN STAFF
Figure 1: Organizational Structure of DCVI
5
The MVT Department
The Department is responsible for maintenance of automobiles and equipment like vehicles,
graders, rollers, tractors, caterpillars among others and general automotive works.
At DCVI, interns are attached to the different Departments on the basis of the respective courses
they pursue. The Departments then design training programs for them. Mechanical Engineering
interns are attached to the MVT and/or MECP Departments. As such, I was attached to the MVT
Department. Its organizational structure is shown in Figure 2 below.
Head of Department
Motor Vehicle Technicians
Support Staff
Figure 2: Organizational Structure of the MVT Department
The Motor Vehicle Workshop
This is the referral workshop for all auto-mobiles of DCVI and Gulu Archdiocese institutions.
Vehicles and equipment from Gulu Municipality and neighboring areas are also serviced here. It
is thus responsible for maintaining and ensuring that they are all in good mechanical and
electrical working conditions. It is located within the institute.
A number of activities are carried out in this workshop with an aim of keeping the motor
vehicles and equipment in good operating conditions. Some of these activities include; Engine
overhaul, gear box overhaul, auto-body repair, general servicing and minor repairs among others.
All the activities are carried out by experienced auto-mechanics and electricians who are wellversed with the motor vehicle internal and external systems.
The fleet of the workshop consists of tractors, construction equipment, service vehicles,
managerial vehicles and Executive vehicles. They total up to approximately 220 in number.
While training at the workshop, I engaged in very many activities as exhaustively explained in
chapter three.
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CHAPTER TWO: MOTOR VEHICLE TECHNOLOGY
Introduction
A motor vehicle is a self-propelled road vehicle or off-road vehicle, commonly wheeled, that
does not operate on rails, such as trains or trams and used for the transportation of passengers, or
passengers and property. The vehicle propulsion is provided by an engine or motor, usually by
an internal combustion engine, or an electric motor, or some combination of the two, such as
hybrid electric vehicles and plug-in hybrids.
Vehicle Systems
An automobile is the result of combined work of a number of systems. Each system, though
primarily independent, is influenced by the effect of other systems interacting with it. The
different systems are given below.
The Transmission System
Transmission system in a car helps to transmit mechanical power from the car engine to give
kinetic energy to the wheels. It is an interconnected system of gears, shafts, and other electrical
gadgets that form a bridge to transfer power and energy from the engine to the wheels. The
complete set up of the system, shown in Figure 3 below, helps to maintain the cruising speed of
the car without any disturbance to the car’s performance.
Figure 3: The Transmission System
Link to the image: (http://usciencecompendium.blogspot.com/2014/12/automobile-transmission-systempart-1.html)
7
The Electrical System
The electrical system, shown in Figure 4 below, consists of the battery, starter and alternator. The
battery provides juice to the starter. Then, the alternator gives that battery the energy it needs to
power the car. If one of these parts is not working properly, the car won’t start or run correctly.
a Battery
Until your vehicle starts, the battery provides the car’s entire electrical current. This includes the
current to the ignition and fuel systems, which are responsible for creating the combustion necessary
for the engine to function.
b Starter
While the battery supplies the power to start the vehicle, the starter is really what gets the engine
going. The battery supplies a small amount of power to the starter motor. The starter then rotates the
flywheel, which turns the crankshaft and begins the movement of the engine’s pistons. This intricate
process is why it’s key to make sure the starter works.
c Alternator
When the engine is running, the alternator keeps the battery charged and the electrical system going.
The car can start with a faulty alternator, but it won’t be able to run for an extended period of time. If
the alternator requires replacement, the vehicle’s electrical system will perform erratically, its battery
will discharge, and eventually the engine will lose power.
Figure 4: The Electrical System
Link to the image: (https://repairpal.com/electrical-lights)
8
The Fuel System
All internal combustion engines need three things to run:-Air, Fuel and Spark. The fuel system is
critical in storing and delivering the gasoline or diesel fuel the engine needs to run. The fuel system
has the following components:-fuel pump, fuel lines and filter as shown in Figure 5 below. A failure
in any of these fuel system components has devastating effects on the car.
a Fuel tank
This is basically a holding tank for the fuel. When you fill up at a gas station, the gas travels
down the filler tube and into the tank. In the tank there is a sending unit which tells the gas gauge
how much gas is in the tank. In recent years the gas tank has become a little more complicated,
as it now often houses the fuel pump and has more emissions controls to prevent vapors leaking
into the air.
b Fuel pump
On newer cars the fuel pump is usually installed in the fuel tank. Older cars have the fuel pump
attached to the engine or on the frame rail between the tank and the engine. If the pump is in the
tank or on the frame rail, then it is electric and is run by the car’s battery. Fuel pumps mounted to
the engine use the motion of the engine to pump the fuel, most often being driven by the
camshaft, but sometimes the crankshaft.
c Fuel filter
Clean fuel is critical to engine life and performance. Fuel injectors and carburetors have tiny
openings which clog easily so filtering the fuel is a necessity. Filters can be before or after the
fuel pump, sometimes both. They are most often made from a paper element, but can be stainless
steel or synthetic material and are designed to be disposable in most cases. Some performance
fuel filters will have a washable mesh, which eliminates the need for replacement.
d Fuel injectors
The fuel injector is basically a tiny electric valve which opens and closes with an electric signal.
By injecting the fuel close to the cylinder head, the fuel stays atomized (in tiny particles) so it
will burn better when ignited by the spark plug.
e Carburetors
A carburetor takes the fuel and mixes it with air. While simple in operation, they tend to need
frequent tuning and rebuilding. This is why newer cars have done away with carburetors in favor
of fuel injection
9
Figure 5: The Fuel System
Link to the image: (http://www.xpertechautorepair.com/fuel_injection.html)
The Braking System
The Vehicle’s braking system, shown in Figure 6 below, is designed to perform only one job
and that is to safely stop the vehicle. In order to achieve that, there are three key things needed:a vehicle operator, hydraulic pressure and friction. When the vehicle operator pushes the brake
pedal down, the pedal levers and rods actuate the power brake booster. The booster uses engine
vacuum or a pump to multiply the force from the operator’s foot to the master cylinder.
Hydraulic lines connected to the master cylinder go out to a proportioning valve or to the
ABS (Antilock Brake System) module then to each either brake caliper if the vehicle has
disc brakes or to wheel cylinder if it has drum brakes. The brake fluid in the lines flows into the
calipers or wheel cylinders and the hydraulic pressure pushes the brake pads against the rotors of
brake shoes against the drums causing friction which stops the vehicle.
a
Disc Brakes
A disk brake system consists of a brake disk, a brake caliper and brake pads. When the brake
pedal is applied, pressurized hydraulic brake fluid squeezes the brake pad friction material
against the surface of the rotating brake disc. The result of this contact produces friction which
enables the vehicle to slow down or stop.
10
b Drum brakes
A drum brake system consists of hydraulic wheel cylinders, brake shoes and a brake drum. When
the brake pedal is applied the two curved brake shoes, which have a friction material lining, are
forced by hydraulic wheel cylinders against the inner surface of a rotation brake drum. The result
of this contact produces frictions which enables the vehicle to slow down or stop.
Figure 6: The Braking System
Link to the image: (https://www.pinterest.com/pin/360076932694018134/)
The Suspension System
Suspension is the system of tires, tire air, springs, shock absorbers and linkages that connects a
vehicle to its wheels and allows relative motion between the two. Suspension systems serve a
dual purpose:-contributing to the vehicle's road-holding/handling and braking for good active
safety and driving pleasure, and keeping vehicle occupants comfortable and reasonably well
isolated from road noise, bumps, and vibrations. The suspension also protects the vehicle itself
and any cargo or luggage from damage and wear. The design of front and rear suspension of a
car may be different. The suspension system of the motor vehicle, shown in Figure 7 below, is divided
into front suspension and rear suspension.
11
Figure 7: The Suspension System
Link to the image: (http://www.avgnewton.com/suspension.html)
a
The Front Suspension System
The purpose of the front suspension is to support the weight of the vehicle. Automobiles
commonly use independent front suspension whereby if one of the tires moves over a bump, the
other will not be affected. The front suspension, shown in Figure 8 below, is mainly composed
of the following; ball joints, control arms, shaft bushings, coil springs, stabilizers, shock
absorbers, steering knuckle and spindle.
12
Figure 8: The Front Suspension System
Link to the image: (http://eramandeepbansal.blogspot.ug/2013/08/front-wheel-suspensionsystem.html)
b The Rear Suspension System
The rear suspension system is designed to keep the rear axle and the wheels in their proper
position under the car body. The rear suspension allows, shown in Figure 9 below, each of the
rear wheels to move up and down independent of the frame so as to maintain alignment and good
vehicle control. The main components include leaf springs which are used to dampen noise and
vibrations from the road to the frame of the vehicle, and shock absorbers which are hydraulic
device that help to control the up, down and rolling of the car body
13
Figure 9: The Rear Suspension System
Link to the image: (http://arrc.ebscohost.com/ebsco_static/repairtips/8852CH23_Rear_Suspensions.htm)
The Steering System
The steering system, shown in Figure 10 below, converts the rotation of the steering wheel into a
swiveling movement of the road wheels in such a way that the steering-wheel rim turns a long
way to move the road wheels a short way. There are two steering systems in common use - the
rack and pinion and the steering box. On large cars, either system may be power assisted to reduce
further the effort needed to move it, especially when the car is moving slowly.
a
The rack-and-pinion system
At the base of the steering column there is a small pinion (gear wheel) inside a housing. Its teeth
mesh with a straight row of teeth on a rack - a long transverse bar. Turning the pinion makes the
rack move from side to side. The ends of the rack are coupled to the road wheels by track rods.
This system is simple, with few moving parts to become worn or displaced, so its action is
precise. A universal joint in the steering column allows it to connect with the rack without
angling the steering wheel awkwardly sideways.
14
b The steering-box system
At the base of the steering column there is a worm gear inside a box. A worm is a threaded
cylinder like a short bolt. Imagine turning a bolt which holding a nut on it; the nut would move
along the bolt. In the same way, turning the worm moves anything fitted into its thread.
Depending on the design, the moving part may be a sector (like a slice of a gear wheel), a peg or
a roller connected to a fork, or a large nut.
The nut system has hardened balls running inside the thread between the worm and the nut. As
the nut moves, the balls roll out into a tube that takes them back to the start; it is called a
recirculating-ball system. The worm moves a drop arm linked by a track rod to a steering arm
that moves the nearest front wheel. In recirculating-ball steering, the thread between the worm
and nut is filled with balls.
Figure 10: The Steering System
Link to the image: (https://repairpal.com/suspension-steering)
The Intake and Exhaust Systems
Combustion requires air, fuel, and heat; certain ratios of all three are necessary if an engine is to
operate. The purpose of the exhaust and intake processes is to remove the burned gases at the end
of the power stroke and admit fresh charge for the next cycle.
a Intake System
The intake system’s job is to regulate the flow of clean, filtered air at the right temperature to the
engine and to provide vacuum to operate other devices. Most factory intake systems are designed
15
to generate as little noise as possible. The intake system, shown in Figure 11 below, also pulls
crankcase vapors into the intake stream so the engine can burn them. Older carbureted engines
do not have much of intake system. Usually just an air filter mounted on top of the carburetor,
which is mounted on the intake manifold, is enough for those engines. Modern day vehicles have
much more intake plumbing to accommodate smaller engine bays which have much technology
more packed into them.
Figure 11: The Intake System
Link to the image: (https://www.coolcaraircon.co.uk/how-car-air-conditioning-works/)
b The Exhaust System
The exhaust system, shown in Figure 12 below, is an assembly in a vehicle's engine that takes
care of the burnt gas that the engine produces. It consists of exhaust pipes, through which
exhaust gas flow through from one chamber to another, a header, which collects the same gas
from different cylinders and directs it to the pipes, a catalytic converter, which converts the
pollutant gases produced during combustion into less harmful substances, a muffler, which
reduces engine noise, and a turbocharger, which increases engine power. The exhaust system is
vital to any vehicle because the life and performance of the vehicle's engine depends on it. An
engine cannot function well if there is back pressure trapped in it. Trapped exhaust gas chokes an
engine and stops it from doing productive work. As a result, the vehicle cannot run smoothly and
silently, or in the worst cases, will not run at all.
16
Figure 12: The Exhaust System
Link to the image: (https://mechanicalserviceswi.com/auto-repair/exhaust-system)
17
CHAPTER THREE: HANDS-ON ACTIVITIES CARRIED OUT
Introduction
During my training at DCVI, I participated in different practical activities where I applied the
theoretical knowledge and skills acquired in class into real world problem solving situations. The
activities included among others; Clutch adjustment, diagnosis and correction of battery failure,
tire replacement, diagnosis and correction of power steering faults of a car and replacement of
hydraulic oil of a truck. They are detailed below.
Diagnosis and correction of failure of a car battery
Battery failure is often reported and is one of the major causes of vehicle breakdowns. With
modern vehicles full of complex and sensitive electrical equipment that constantly draw current
from the battery, an ever-increasing number of mechanical faults from new and older vehicles
alike are battery related. However, the expense and inconvenience of battery failure could be
heavily reduced by regular battery maintenance. Figure 13 below shows the operation.
Common faults of the car battery, their causes and remedies
The following are the common faults associated with the car battery; their causes and
corrections.
a Low charge
This is caused by leaving the battery in uncharged condition for a long time and also when
battery usage exceeds battery capacity.
Solution: The best solution for this problem is to recharge the battery. A jump start as well as a
trickle charger can be used for this operation. A trickle charger is most commonly used. It
delivers electricity to the battery from a power outlet in a slow, steady stream. It has an electric
cord with a plug and two jumper cables with alligator clips.
b Sulphation
If the battery is allowed to stand in a discharged state either on or off the vehicle for a long
period of time, a chemical reaction takes place which permanently impairs the performance and
life of the battery. It can be seen as a fine white/grey coating of the positive plate. This is called
Sulphation.
Solution: Clean the battery terminal.
c Wear and tear due to ageing
As the battery is charging and discharging, the active materials within the battery plates are in
motion in order to release electricity stored by the battery. This leads to the wear and tear of the
battery when used for a long period of time.
18
Remedy: Replace the battery.
d Incorrect application
This is when the battery is not correctly applied or installed. Therefore, it cannot function
properly on the vehicle.
Remedy: Ensure that the correct battery in the right condition has been used in the right
application.
e Low acid stratification
This is when the electrolyte on the stratified battery concentrates on the bottom causing the
upper half of the battery to be poor.
Remedy: Replace the electrolyte.
f Low acid level
This is when the level of the acid in the battery is not enough as required.
Remedy: Refill the battery to required level.
g
Slipping
This occurs due to incorrectly adjusted alternator charging the belt.
Remedy: Adjust the alternator to required recommendations.
h Overcharging
If the alternator regulator is not set properly, an alternator voltage control circuit fails. Then the
battery can be subjected to an excessive charge. If left unchecked for a long time, the battery will
overheat and will start to evaporate the electrolyte.
Remedy: Replace regulator with another.
i Electrical faults
These are caused by excessive use of electric consumers for example air conditioning, long
standing time without recharge, vehicle lightings and hazard flashers left on.
Remedy: Recharge the battery; lightings and flashers should not be left on.
Fault found with the battery
After the diagnosis, it was found that the battery had low charge. The problem was corrected by
recharging the battery.
19
Tools and equipment used to recharge the battery
The following tools were used to recharge the battery; Trickle charger, Power stroke, Manual
sand paper pad and a pair of pliers.
Technical procedures followed
The following procedures were followed to recharge the battery;
a. The battery terminals were checked and cleaned using a manual sand paper.
b. The cell caps were removed.
c. The charger cables were attached with the car turned off.
d. The charger was turned on for the battery to charge itself.
e. The battery was checked to find out whether it worked after charging and it functioned
properly.
Figure 13: Recharging the battery
Replacement of water pump of a Cesspool truck
The engine of a vehicle needs coolant just as much as it needs oil. Engine coolant helps protect
against high heat. It is cycled from the radiator throughout the engine, absorbing heat from
engine operation and then allowing that heat to wick away into the atmosphere at the Radiator.
The water pump is the key to making the entire system work. It is an impeller pump, buried
under the timing belt cover on the side of the engine. The pump is operated by the drive belt of
20
the engine – as the belt turns, the pump turns. Blades on the pump force the coolant to flow
through the engine. Figures 14 and 15 below show the operation.
When the water pump fails or is beginning to wear out, it can lead to complete engine failure.
The water pump is the key to making the entire system work. Like any other mechanical
device, they will produce a few warning signs that they are wearing out.
Common faults with water pumps, their causes and remedies
Table 2 below shows the common faults with water pump, their causes and remedies. The water
pump experiences many faults.
Table 2: Water pump troubleshooting chart
FAULT
POSSIBLE CAUSE
Weep-hole leakage.
Appearance: The internal
mechanical seal of the pump
seals the shaft towards the
cooling circuit, protecting the
bearings by preventing
coolant from passing into the
Contaminated coolant is the
bearing assembly. When a
main cause of weep hole
water pump is new, some
leakage
seepage from the weep hole
is normal as it takes about ten
minutes of operation for the
mechanical seal to properly
seat itself (break-in period).
More pronounced seepage
and drips from the weep hole
after this break-in period or a
large coolant bleed mark
around the weep hole are
abnormal and indicate
impending water pump
failure.
Leakage from the mounting
Improper water pump
surface.
installation or improper use of
the seals/gaskets or sealant.
Appearance: Seepage drips
or large coolant bleeds marks
on or around the mounting
surface or on the housing.
21
REMEDY
Thoroughly flush the cooling
system before installing the
new pump and refill the
system with the recommended
coolant of the manufacturer of
the vehicle
In case of a recently installed
new water pump, carefully
remove, check and reinstall
the water pump.
Rust and corrosion.
Appearance: Rust and
corrosion on the surfaces of
the water pump, for example
corrosion of the impeller fins
makes the pump ineffective in
moving the coolant.
Deposit build-up.
Appearance: Deposits,
sludge and scale build up on
the inside, clogging the water
pump and hampering proper
functioning of its individual
components.
Cavitation.
Appearance: Vapor cavities
(bubbles) in the coolant
collapse with explosive
force, pock marking the
individual components of the
pump. The pockmarked areas
then corrode away.
Damaged bearing.
Appearance: With the engine
off, check the condition of the
bearing by looking for any
side-to-side play at the shaft.
Apply hand pressure – there
should be no play at all. Also,
rumbling or screeching noises
coming from the water pump
indicate a worn bearing.
Damaged or broken shaft.
Appearance: The shaft is bent
or broken. A clean break
indicates an instantaneous
Contaminated coolant, noncompatible coolant or mixing
coolants of different
chemistries.
Another possible cause may
be a defective pressure cap
causing air bubbles,
accelerating the rust process.
Replace the water pump.
Thoroughly flush the cooling
system before installing the
new water pump and refill the
system with the recommended
coolant of the manufacturer of
the vehicle.
Inspect the pressure cap and
replace if defective
Contaminated coolant, noncompatible coolant or mixing
coolants of different
chemistries.
Replace the water pump.
The formation of bubbles at the
coolant inlet of the pump. As the
pressure increases in the system,
the bubbles implode cause harm.
Replace the water pump.
Thoroughly flush the cooling
system before installing the
new pump and refill the
system with the correct
vehicle manufacturer’s
recommended coolant
Misaligned belt causes
excessive wear. An overtensioned belt causes overload
on the bearing, accelerating
wear. A damaged mechanical
seal allows coolant to leak
through the bearings and wash
away the lubricator.
Replace the water pump and
make sure to inspect the belt
drive system: belt, tensioner,
pulleys, belt tension and
alignment.
A misaligned belt causes
excessive wear. An overtensioned belt imposes a
powerful bending force on the
Replace the water pump and
make sure to inspect the belt
drive system: belt, tensioner,
pulleys, belt tension and
22
Thoroughly flush the cooling
system before installing the
new pump and refill the
system with the correct
vehicle manufacturer’s
recommended coolant
fracture caused by sudden
overload or imbalance. If the
broken shaft is discolored
(usually blue), the damage
was gradual, indicating
excessive heat build-up before
the shaft broke.
Seal leakage-dirty system
Casting breakage
shaft resulting in shaft bending alignment.
or early shaft fracture.
If equipped with a water pump
Excessive vibrations due to
mounted fan, inspect the fan
lack of maintenance.
or fan clutch assembly. The
fan may not be squarely
mounted on the shaft. A bent
or damaged fan, a worn
spacer, or a worn or damaged
fan clutch could also be
factors contributing to the
break.
Thoroughly flush a
contaminated system before
replacing the water pump.
Cooling system contamination Check the system pressure.
Use correct coolant mixture.
Use distilled water where
necessary.
Carefully inspect pulley, belt
alignment and fan/fan clutch
Excessive vibration
assembly, replacing any bent
or worn components.
Take proper precautions when
filling your radiator, especially
when the engine may be very
hot.
Seal leakage-clean system.
Thermal shock
Allow an overhead engine to
sit and cool before adding
coolant.
Then restart engine and allow
it to run while slowly adding
the remainder.
Never start the engine without
coolant.
Fault found with the water pump
The water pump was worn out which could lead to complete engine failure. This prompted its
replacement.
23
Tools and equipment used to replace the pump
A new water pump, ring spanner, box spanner, combination spanner and an adjustable
spanner.
Technical procedures followed
a. The radiator was drained by opening the petcock valve at the bottom of the radiator.
This was done when the engine was cold.
b. The fan belt was removed, carefully noting how it was routed before removing it in
order to reinstall it correctly afterwards.
c. Any other accessories that were blocking access to the pump were removed. This
included the fan, fan shroud, timing belt cover, or any brackets.
d. The water pump was unbolted from the engine.
e. The pump mounting surface was cleaned to remove all traces of old gaskets. The
mounting surface must be clean and dry before installing the new pump.
f. The gasket was positioned on the new pump using gasket sealer or adhesive as
required, and then the new water pump was bolted to the engine.
g. The cooling system was refilled.
Figure 14: The removed water pump
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Figure 15: The unit that houses the water pump
Replacement of hydraulic oil of a FAW truck
Hydraulic fluid is the medium by which power is transferred in hydraulic machinery.
Common hydraulic fluids are based on mineral oil or water mineral oils, synthetic fluids
and fire-resistant fluids. The primary function of a hydraulic fluid is to convey power from
one point to another. There are other important functions of hydraulic fluid such as
protection of the hydraulic machine components, lubrication of system components, transfer
and dissipation of heat, and provision of a seal to maintain pressure.
Examples of equipment that use hydraulic oil include; Excavators and backhoes,
Hydraulic brakes, Power steering systems, Transmissions and Garbage trucks. The
operation is shown in Figure 16 below.
Dangers involved in working with hydraulic fluids
There are several dangers involved while dealing with hydraulic fluids. These include the
following;
a. Health problems.
People can become exposed to the chemicals in hydraulic fluids. The exposure may be due
to inhalation, ingestion, or touch. There are instances of people suffering from skin irritation
or weakness in hands while handling hydraulic fluids. There are also cases of intestinal
25
bleeding, pneumonia, or death through hydraulic fluid ingestion though no serious hazards
are reported with hydraulic fluid inhalation.
Similar to ingestion, fluids can be accidentally injected into the skin as well. This takes place
when the high-pressure hydraulic system hose is disconnected and toxic fluids are leaked and
injected into the skin. If there is a small leak in the hydraulic pipe and someone runs there hand
along it, at 2000 psi, they can easily incur an injection of hydraulic fluid and may not even be
aware that it happened until gangrene begins to set in.
b. Fire dangers.
When working with hydraulic fluid, there is every chance that the hydraulic fluid gets heated to
high temperatures. And it is evident that most petroleum-based hydraulic fluids will burn and
thereby create explosions and burns.
c. Environmental problems.
When the hydraulic hose or pipe leaks, the chemicals of the fluids can either stay on top of the
soil or sink into the ground. If the chemicals get mixed in a water body, they will sink to the
bottom. In fact in such cases the chemicals can stay there for more than a year. Aquatic life can
absorb the toxic hydraulic fluid, leading to illness or death to the animal or anything higher on
the food chain. For example, a hawk that eats a fish that has been contaminated by hydraulic
fluid that was mixed in water could become ill as well.
d. Fluid texture problems.
Although the slimy texture of hydraulic fluids may not seem like a danger or a problem, a spill
can cause a person to slip and fall. Also when there is fluid on the hands of a person, it can cause
him to slip while climbing on a machine. It can also cause the operator to lose steering control.
Safety precautions when dealing with hydraulic fluids
Certain safety precautions need to be followed when handling hydraulic fluids as discussed
below;
a. In order to avoid skin irritations, it is necessary to wash contaminated skin immediately.
It is also necessary to keep your clothing clean.
b. Always wear masks and gloves while using hydraulic fluids.
c. To avoid environmental dangers, there is a biodegradable hydraulic fluid option, though
it is more expensive.
d. To avoid fires, materials and fluids soaked in hydraulic fluid should be stored in sealed
metal containers and disposed of at proper places.
e. To check for leaks, use cardboard.
26
Common faults with the hydraulic system
Generally, improper hydraulic system operation can be traced to one of the following
deficiencies: insufficient fluid level, the presence of air in the system, contamination by foreign
material, incorrect adjustment of components, internal or external fluid leakage, mechanical
damage to components, wrong fluid type or viscosity and excessive temperatures.
Solutions to the common faults
The following tips, tools and techniques should be considered for appropriate use to curb the
faults.
a. The contaminant test. Obtain an oil sample in a clean, clear jar and let it sit overnight. Any
contamination will settle to the bottom of the container and will remain attracted to the
bottom surface for viewing even when the container is turned over.
b. The crackle test. If water is suspected but not obvious, obtain an oil sample and place two
or three drops of the oil on a hot plate. The drops will crackle, pop or sizzle if any water is
present. Remember that any water may be harmful depending upon the equipment type or
process.
c. The “poor man’s” particle count. It is a simple inspection of the filter of the machine. Cut
the filter open, spread the media out on a bench and view any contaminant with a
magnifying glass or microscope. Run a magnet under the filter media. Any ferrous material
will move with the magnet. This should immediately call for a ferrographic analysis of an
oil sample.
d. The color test. Any brownish or darkening discoloration of the oil which is an obvious
change, suggests that oxidation has begun. Any discoloration should be immediately
investigated by sending an oil sample for a minimum of viscosity and acid number analysis.
If the viscosity has increased by 10% or more of new oil and the acid number has increased
substantially, the fluid may have reached the end of its service life and thus replacement is
required.
e. The high temperature test. Dark discoloration of the hydraulic fluid suggests that
oxidation is occurring. If high temperatures are suspected, they could be caused by external
leaks which create hot spots at valves or cylinders, plugged coolers or kinked or damaged
hoses, relief valve pressure settings too high, or oil of too high viscosity. In all cases, the use
of predictive maintenance tools such as infrared thermograph or an infrared thermometer
using laser beams to instantly locate hot spots will locate the high temperature areas.
f. The internal leakage test. When a hot spot is located, such as at a cylinder barrel or servo
valve, the use of a hand held ultrasonic tester will locate the leak. During a leak, a liquid
moves away from high pressure. As it passes through the leak site, a turbulent flow is
generated that has strong ultrasonic sound waves that can be monitored. The intensity of the
ultrasound will be loudest at the actual leak site. These ultrasonic sounds cannot be heard by
the human ear. Very often, external leaks will cause hot spots that will burn the hand of a
27
troubleshooter, so care must be taken when attempting to locate high temperature problems.
g. The excessive noise test. An ultrasonic tester can also be used to monitor conditions such as
cavitation or aeration at hydraulic pump inlets or other components, as well as locating
electrostatic discharge noise at filters or reservoirs. Electrostatic charges may be generated
in hydraulic fluids by turbulence, high fluid velocities, internal fluid friction, fluids flowing
in ungrounded piping or when fluid discharges on to any free surface of the reservoir,
particularly if there is free air present in the fluid.
Electrostatic discharge most often manifests itself as a clicking sound as the charge
repeatedly builds and then discharges to a surface of lower voltage through sparking. The
increased use of synthetic fluids and mineral base oils with non-metallic anti-wear additives
have resulted in fluids with low conductivity, increasing the potential for accumulated static
charge levels. In severe cases, electrostatic discharge can result in etching, pitting or carbon
deposits at the surfaces of the area where the discharge occurred and may leave burn marks
or other damage on the filter element media.
h. The foam and air entrainment inspection. As noted earlier, a darkening color of hydraulic
fluid suggests that oxidation is occurring. Oxidation rates are related directly to high
temperatures and excessive air entrainment combined with high pressure. At atmospheric
pressure and corresponding temperature, oils contain about 10%by volume of dissolved air.
At 200 psi (1400 kPa), oils can absorb about 140% by volume. The dissolved air provides
the oxygen that is necessary to promote oxidation and oxidation rates rapidly increase as
temperatures rise above 140ºF (60ºC) and hydraulic pressures increase to their normal
operating ranges. Dissolved air in oil under pressure will tend to produce foam as pressure is
released and the air comes out of solution. This free air is now trapped inside operating
cylinders and other components, which will cause erratic and spongy operation and
increased temperatures.
If hydraulic systems begin to display erratic, spongy operational behavior or cylinder
extension and retraction speeds are slower than normal or erratic in nature, there is a good
possibility that there is excessive air entrainment in the hydraulic system. The presence of
entrained air is readily apparent by the bubbly, opaque appearance of the fluid in the
reservoir.
When excessive levels of entrained air are suspected, inspect all system connections where
air may be drawn into the system. Examples are; loose pump inlet connections, the fluid
return line is broken or no longer below the oil level in the reservoir, the pump shaft seal has
failed, inadequate or broken reservoir baffle plates, suction side of circuits are leaking or
have loose connections.
Suction leaks (where air is being drawn into a component or circuit) can easily be located by
applying hydraulic oil to the connection. If the oil disappears, the troubleshooter has located
the air leak!
28
Recommendations on hydraulic systems
As hydraulic systems improve and operating pressures increase, much more attention to
predictive maintenance and reliability will be required. Two areas of concern will be a
requirement for improved filter design, selection and installation and hydraulic system flushing
techniques after a component failure has occurred.
In the first instance, more consideration will be required for improved filter installation where
increased vibration and/or higher pressure pulsation will require mitigation.
In the second instance, mobile filtration systems and portable hydraulic fluid purifiers will
become mandatory, if hydraulic system reliability is to be improved and maintained.
Faults found with the hydraulic oil
Diagnosis of the hydraulic oil of the truck, revealed the following faults that necessitated its
replacement;
a. Hydraulic oil had deteriorated. When the hydraulic oil is used for a long time, it
deteriorates and thus has to be replaced.
b. The base oil was degraded.
c. The additive package was depleted.
Tools and equipment used to replace the hydraulic oil
The tools and equipment used to change the hydraulic oil were; a ring spanner, box spanner,
Hammer, combination spanner, funnel, bucket, clean piece of cloth and new hydraulic oil.
Technical procedures followed
The following procedures were observed during the operation;
a.
The system was drained while the fluid was hot to keep contaminants in suspension.
b.
The fluid was emptied from cylinders, accumulators and lines that could not drain
properly.
The oil left in the reservoir was pumped out.
c.
d.
e.
f.
The reservoir was wipe-cleaned with lint free rags and rust and free paint were
removed.
Filter elements, strainers, and housing were cleaned.
The system was refilled with new hydraulic fluid making sure to vent high points.
g.
The system was restored and checked for proper operation after which it functioned.
29
Figure 16: Draining the hydraulic oil
Replacement of leaf springs of a FAW truck
The rear suspension under some vehicles is supported by a pair of leaf springs made up of
multiple leaves (strips) of spring steel. A leaf spring is a component of suspension systems of
some vehicles. They are composed of several (or occasionally just one) thin strips of metal,
called leaves, arranged on top of each other to form a single curved piece. Typically, they have
three or four individual leaves that make a set of springs. Leaf springs have a specific curvature,
and this curvature and the number of leaves in the spring pack; determine the load capacity and
the ride height of the vehicle. The curvature also helps the spring absorb impact. The bending of
the leaves and the friction between them as they slide slightly over each other while bending,
absorb the weight of the vehicle as well as any bumps. Leaf springs should be replaced when
they are worn out, flattened out, cracked or broken. Figures 17 and 18 below show the
operation.
30
Functions of the suspension of the vehicle
The suspension of the vehicle serves three major functions; they are to;
Support the vehicle
b. Absorb impacts from bumps, potholes, and other road irregularities
a.
c.
Allow the vehicle to turn in response to the driver’s inputs. (The steering system can be
considered part of the suspension, or its own system, but either way the suspension has to
allow for movement of the wheels as the vehicle turns).
The purpose of leaf springs
Leaf springs are appropriate for spreading heavy loads over a large area (because they are
attached to the vehicle at the ends, which may be several feet apart) and for suspension designs
that incorporate a “solid” axle rather than independent suspension for each wheel especially of
heavy vehicles such as trucks.
These factors render leaf springs appropriate for trucks and other heavy vehicles but less so for
cars, as such designs tend to have undesirable effects on the handling of the vehicle. As
independent (as opposed to solid axle) rear suspensions have become increasingly common on
cars, leaf springs are now found primarily on trucks, vans, SUVs and trailers.
Maintenance of leaf springs
Multi-leaf springs occasionally get “sticky” as dirt works its way in between the leaves; the
effect can be to make the ride slightly stiffer, but this is rarely a significant problem. The
attachment points will need to be checked periodically and lubricated in some cases as specified
by the manual of the manufacturer, and regular maintenance should be carried out. If the body of
the car seems to sit too low over the wheels, this sagging is usually due to the leaf springs having
bent slightly over time, and the solution is to have them replaced.
Fault found with the leaf springs
The leaf springs were broken as depicted by inspection. This necessitated their removal and
replacement.
Safety precautions while replacing leaf springs
The following precautions should be observed when replacing the leaf springs;
a. Always wear safety glasses when working carrying out the operation.
b. Wear other personal protective equipment (PPE) when necessary, for example latex
gloves or closed toe shoes.
31
Tools and equipment used to replace the leaf springs
The following tools and equipment were used to replace the leaf springs of the truck;
A ratchet, hammer, Box spanner, combination spanner (24-24), floor jack, trolley jack, lubricant
(oil); ring spanners (numbers16, 18, 19 and 30), wrenches and Jack stands.
Technical procedures followed to replace the leaf springs
a.
The vehicle was parked on a solid, level surface to ensure that it did not roll or lean when
raised.
b.
Using a floor jack, the rear of the vehicle was lifted up enough for the axle assembly to
hang freely.
c.
d.
e.
f.
g.
h.
The vehicle was secured with jack stands on both sides for safety before starting any
work.
The rear axle assembly was supported with a floor jack close to the spring.
The lower bolt was removed from the shock absorber.
The axle was lowered to relieve tension on the spring.
The U-bolts and spring retainer bracket were removed.
The parking brake cable was removed from the retainer bracket.
i.
j.
The rear axle was carefully lowered since leaf springs were mounted on top of the axle.
The rear shackle bolts were loosened.
k.
The leaf springs were supported with a jack stand and the leaf spring front and rear eye
bolts were removed.
The leaf springs were removed from the vehicle.
l.
m.
The front bushings of the new springs were placed into the front mounting brackets, the
front eye bolts and nuts were installed with the bolt heads towards the center of the
vehicle.
n.
The rear bushings of the new springs were placed into the rear shackles and the rear eye
bolts and nuts were loosely installed.
o.
The axles were adjusted to place the leaf springs center bolts into the holes on the axle
pads.
p.
The U-bolts and retainer brackets were installed; the U-bolt nuts were snagged down but
not tightened.
q.
The parking brake cable was reattached and the lower shock mount was attached to the
axle bracket.
Steps (d) through (q) were repeated for the other side of the truck.
The truck was lowered to the ground and all bolts torqued to the recommended
specifications.
The leaf springs repair was verified and the vehicle was aligned.
The vehicle was road-tested and found to operate well.
r.
s.
t.
u.
32
Figure 17: Removing the broken leaf springs
Figure 18: The broken leaf springs that were removed
33
Replacement of a tire of a garbage truck
Tires are often the most neglected components on vehicles, but better care should be taken of
them, our lives on the ride depend on them. They support the overall weight of the vehicle and
thus must be in good conditions to function properly. They are one of the most important
components of the vehicle. The tire tread area making contact with the road is relatively small–
only about the size of the palm of the hand - so if tires are worn or damaged it can seriously
affect the safety and handling of the vehicle. Figure 19 below shows the operation.
Common tire problems and their solutions
Tires wear abnormally as the result of excessive sharp braking or rapid acceleration. The guide
below for what to look out for will help when inspecting tires:
a. Illegal wear. When a tire is worn, it needs replacing immediately. Any tire in this
condition has been used far beyond the legal tread depth limit.
b. Misalignment. A misaligned tire will be worn noticeably more on one side than the
other. For example, a tire aligned inwards will wear more on the outside than the inside.
If the tire is aligned outwards the inner shoulders of the tire wear more than the outer
shoulders. Any tire in this state should be replaced immediately.
c. Camber wear. Cambered wheels result in increased wear on the outer edge of a tire.
Cambering occurs due to poor fitting and this significantly reduces the lifespan of a tire.
Wheels should be repaired.
d. Emergency braking. If an emergency stop is performed, the tire wears enormously in an
isolated area and can lead to deflation. If an emergency stop maneuver has recently been
executed, check the tires for isolated damage.
e. Cuts and tears. Observe the sidewalls of the tires. Sharp objects such as nails, glass or
metal can cause a cut or tear in the tire. If a cut or tear is spotted it can render your tire
unserviceable. Tires in this state should be replaced immediately.
f. Impact damage. If a vehicle hits an object at high speed such as a kerb, a bulge may be
visible in the side wall of the tires. The area of the bulge or egg highlights the location of
casing damage. The damage should be diagnosed and fixed immediately.
Minimizing tire problems
Tires are the only point of contact that the vehicle has with the road and as such, they need to be
in good working condition at all times to ensure the safety of the users. To minimize tire
problems and thus maximize the life of tires and achieve optimal performance from the vehicle,
observe the following:
a. Ensure that tires are correctly inflated. Driving with incorrect tire pressures can affect
handling and braking of a vehicle, particularly in wet conditions, and can seriously
compromise safety of users. In some cases, tires are over-inflated which inhibits vehicle
handling and causes excessive wear on the centre strip of a tire. Driving on severely
under-inflated tires can cause heat build-up and eventually a premature failure. Check tire
34
b.
c.
d.
e.
pressure regularly and before every long trip.
Observe the load capacity. Do not exceed the load capacity relative to the load index of
the tires. Overloading a vehicle increases strain upon the tires which raises temperatures,
causes rapid wear and significantly heightens the risk of receiving impact damage that
leads to premature failure. Consult the vehicle handbook to find pressures should there be
need to fully load the vehicle.
Manage the speed of the car. Driving at very high speeds over long and short distances
causes tire temperatures to increase, which in some cases can lead to tire damage. If tires
are not correctly inflated, driving at high speeds also increases the likelihood of sudden
tire failure and rapid loss of air. To maximize the life of tires, observe speed limits and
avoid aggressive acceleration/deceleration.
Make use of spare tires. If any damage to a tire or wheel is seen, replace tire with spare
tire and have tires checked by a professional.
Inspect the tires. It may not always be noticed if one of the tires has been damaged.
Inspect tires regularly for wear and any damage to avoid any sudden problems. Also,
have a professional inspect the tires every year.
Note: Unfortunately many tire problems are unavoidable. Tires can be checked regularly
but still fall foul of an errant nail, piece of metal or a pesky pothole. However, if the
guidelines are followed and tell-tale signs of potential problems are looked out for;
longest life possible out of tires can be got.
Fault found with the tire
Inspection of the tire indicated that it was worn out; this prompted its removal and replacement.
Safety procedures while replacing tires
While changing tires, the following safety measures should be observed.
a. The tire levers should not be sharp. This is because the tube might get cut during the
process.
b. While changing tires, put little French chalk inside the tire. It works as a lubricant.
c. Sometimes, tire bead may get stuck on rim due to rusty rim. Do not apply extra force. In
this case, put little water on tire bead and leave it for 20 minutes and then try again.
d. Always put few amounts of air inside the tube before fixing bead of tire. This air prevents
the cutting of tube and keeps it away from lever and rim.
e. While inflating tires, ensure that the tire is resting nicely on the rim flange. This setting is
very important for heavy duty vehicles especially Tractor tires.
f. After the steps to change tires have been completed, tighten the nuts and only then,
remove the jack.
g. After removing the Jack, the nuts should be tightened again for safety.
35
h. The wheel nuts should be checked more often in new vehicles-after every few hundred
kilometers. The reason for regular checking in case of new vehicles is that wheel nuts
might become loose due to the paint.
Tools and equipment used to replace the tire
A hammer, ring spanner, wrench, floor jack, trolley jack, combination spanner, box spanner and
an open spanner.
Technical procedures followed
a.
The truck was parked on a flat surface.
b.
The parking brake was applied and the truck put in to park position.
c.
Rocks were placed in front of the front and back tires.
d.
The jacks were placed under the frame near the tire that was to be replaced.
e.
The jacks were raised until they were supporting but not lifting the car.
f.
The hubcap was removed and the nuts loosened by turning them counterclockwise.
g.
The jacks were pumped to lift the tire off the ground.
h.
The nuts were removed by turning them counterclockwise until they loosed.
i.
The tire was then removed.
j.
The spare tire was placed on the hub, its rim aligned with wheel bolts and lug nuts
put in positions.
k.
The nuts were tightened using the wrench in a star pattern.
l.
The truck was lowered without applying full weight on the tire, and the nuts were
tightened further.
m.
The truck was fully lowered to the ground.
n.
The jacks were removed.
o.
The nuts were tightened finally and the hubcap replaced.
p.
The truck was road-tested and the new tire was found to be functioning
well.
36
Figure 19: Removing the tire
Troubleshooting starter motor of a Toyota Pick-up
Before an engine starts, it must first be cranked. Turning the engine over draws air and fuel into
the cylinders and compresses the mixture so it can be ignited to provide power. Cranking the
engine also generates the ignition and crankshaft position sensor signals that are needed to fire
the spark plugs and operate the fuel injectors. Cranking the engine is achieved with the help of
the starter.
So if a starter fails to crank the engine or turns too slowly, the engine will not start.
Unfortunately, starting problems are not always simple to diagnose. Sometimes the starter motor
is blamed for a hard starting or no-start condition that is not the fault of the starter. As a result,
some starters are replaced unnecessarily.
One way to avoid such predicaments is to bench-test old starters to make sure they are defective
before they are replaced by new ones. After removing your old starter, you can test the current
draw and cranking speed of the starter. Figure 20 below shows the operation.
Common symptoms of a failing or bad Starter, their causes and remedies
They include the following:
a. Grinding noise. When the starter drive gear is worn out or not engaging properly, they
will often produce a grinding noise that is similar to the one that is heard if engine is
started and then accidentally the starter is hit again. If the grinding symptom is ignored, it
37
b.
c.
d.
e.
f.
g.
h.
may also result in damage to the engine flywheel. It should be diagnosed immediately
upon detection.
Freewheeling. Freewheeling occurs when the engine is cranked and simply a whining
noise is heard from the starter without the engine cranking. When this occurs, it means
the starter gear is not engaging with the flywheel. This is a bad situation that could result
in the need for a starter replacement. If this is occurring, the vehicle should be serviced
as soon as possible.
Smoke. Seeing smoke is cause for immediate concern, and can indicate a few different
problems with the starter or starting circuit. Smoke usually indicates that too much power
is being drawn through the electrical supply to a starter, either because the starter is
shorted, has been operated too long without a rest or there is a connection problem.
Smoke might also be accompanied by a burning smell. If smoke is seen, the vehicle
should be serviced by a professional as soon as possible.
Oil soak. The starter is often located around the bottom of the engine and is vulnerable to
soaking from leaks from the engine oil or other drive train fluids. An oil-soaked starter
likely has a short life remaining. Consider correcting the leak and replacing the starter
before a malfunction occurs.
Malfunctioning solenoid. The solenoid transmits electrical current from the battery to
the starter motor when the key is turned in the ignition of the vehicle and also pushes the
starter drive into the flywheel to allow cranking. Without the solenoid, the starter does
not work. If the key is turned to the crank position and nothing happens, try jiggling the
transmission gear shift lever first. If the engine still will not crank, there might be
something wrong with the solenoid.
When the key is turned to crank the engine, nothing happens. The engine does not
turn over.
When the key is turned to crank the engine and all that is heard is one loud click.
The engine does not turn over; or when the key is turned to crank the engine and the
engine turns over very but very slowly and then stops.
When the battery is good but the car fails to start.
Safety procedures while troubleshooting a starter motor
While troubleshooting a starter motor, certain safety measures need to be observed. They include
the following:
a. If you have to lift up the car or truck to access the starter motor: Use jack-stands to
support the car or truck off the ground, and use safety glasses while working underneath
the vehicle.
b. You will need a helper to crank the engine as you perform some of the tests, and to help
you perform the very important Voltage Drop Test.
c. When jumpering 12 Volts to the S-terminal wire (circuit) make sure you do not short-toground your jumper wire.
38
Tools and equipment used
Spanners (Open, fixed, adjustable, combination and box), safety glasses, jack stands, a
voltmeter, pair of pliers, screwdriver, jack, and multi-meter.
Technical procedures followed
a. The state of charge of the battery was determined.
b. The ignition switch was checked if it was sending power to the solenoid.
c. The starter motor was checked if the problem lied in itself
d. The solenoid was tested to see if it was working.
Testing the starter
a. The battery was tested first, using a multi-meter.
b. The starter motor was tested if it was receiving 12 Volts on its battery circuit.
c. The starter motor was tested if it was receiving the start signal from the ignition
switch.
d. The starter battery and ground circuits were voltage-drop-tested.
e. Using a jumper-wire, 12 volts was applied to the Start signal wire.
f. The engine was turned by hand to eliminate a locked-up engine or a locked-up
AC compressor.
Figure 20: Testing the voltage being received by the starter
39
Adjusting the clutch of a garbage truck
If the clutch is maintained properly, it can be good for the life of the vehicle. Most modern
vehicles with manual transmissions have self-adjusting clutches that require no adjustment, but
models without self-adjustment should be properly adjusted. Figures 21 and 22 below show the
operation.
Common faults with the clutch system, their causes and remedies
They are summarized in Table 3 below.
40
Table 3: Clutch diagnosis/troubleshooting chart
FAULT
POSSIBLE CAUSES
1. Improper linkage
adjustment.
2. Improper pedal travel.
3. Loose linkage.
4. Faulty pilot bearing.
5. Faulty driven disc.
6. Fork off ball stud.
7. Clutch disc hub
binding on clutch gear
spline.
8. Clutch disc warped or
bent.
9. Loose pivot rings in
Fails to Release (Pedal pressed
cover assembly.
to floor). Shift lever does not
move freely in and out of
reverse gear.
1. Improve
adjustment (no
lash).
2. Oil soaked driven
Slipping.
disc.
3. Worn facing or
facing torn from
disc.
4. Warped pressure
plate or flywheel.
5. Weak diaphragm
spring.
6. Driven plate not
seated in.
7. Driven plate
overheated.
Grabbing or
Chattering.
1. Oil on facing. Burned
or glazed facings.
2. Worn splines on clutch
gear.
3. Loose engine
mountings.
4. Warped pressure plate
or flywheel.
5. Burned or smeared
resin on fly wheel or
pressure plate.
41
1.
2.
3.
4.
5.
6.
7.
8.
9.
1.
2.
3.
4.
5.
6.
7.
1.
2.
3.
4.
5.
REMEDY
Adjust linkage.
Trim bumper stop and
adjust linkage.
Replace as necessary.
Replace bearing.
Replace disc.
Install fork onto stud.
Lightly lubricate
fingers at release
bearing.
Repair or replace
clutch gear and/or disc.
Replace disc (run out
should not exceed
0.020″).
Replace plate and
cover assembly.
Adjust linkage to
specifications.
Install new disc and
correct leak at its
source.
Replace disc.
Replace pressure plate
or flywheel.
Replace pressure plate.
(Be sure lash is
checked before
replacing plate.)
Make 30 to 40 normal
starts. Caution: Do not
overheat.
Allow to cool–check
lash.
Install new disc and
correct leak.
Replace transmission
clutch gear.
Tighten or replace
mountings.
Replace pressure plate
or flywheel.
Sand off if superficial,
replace burned or heat
checked parts.
Rattling-Transmission
Click
Throw-out bearing
noise with clutch fully
engaged
Noisy
Pedal stays on floor
when released
Hard pedal effort
1. Weak retracting
springs.
2. Release fork loose on
ball stud or in bearing
groove.
3. Oil in driven plate
damper.
4. Driven plate damper
spring failure.
1. Improper adjustment.
No lash.
2. Release bearing
binding on
transmission bearing
retainer.
3. Insufficient tension
between clutch fork
spring and ball stud.
4. Fork improperly
installed.
5. Weak linkage return
spring.
1. Worn release bearing.
2. Fork off ball stud
(heavy clicking).
3. Pilot bearing loose in
crankshaft.
1. Bind in linkage or
release bearing.
2. Springs weak in
pressure plate.
3. Springs being over
traveled.
1. Bind in linkage.
2. Driven plate worn.
1. Replace pressure plate.
2. Check ball stud and
retainer.
3. Replace driven disc.
4. Replace driven disc.
1. Adjust linkage.
2. Clean, re-lubricate,
check for burrs, and
nicks among others.
3. Replace fork.
4. Install properly.
5. Replace spring.
1. Replace bearing.
2. Install properly and
lubricate fork fingers
at bearing.
1. Lubricate and free up
linkage and release
bearing.
2. Replace pressure plate.
3. Adjust linkage to get
proper lash, make sure
proper pedal stop
(bumper) is installed.
1. Lubricate and free
linkage.
2. Replace driven plate.
Faults found with the clutch system
Inspection of the clutch system revealed the following faults that prompted the operation.
a. The clutch was getting worn out.
b. There was difficulty shifting-the shifter was not moving freely.
42
Tools and equipment used to adjust the clutch
The following tools and equipment were used to carry out the operation
A drive ratchet, socket, large screwdriver, drop Light, piece of wood, floor pads, fan and an
extension cord
Technical procedures followed
a. The parking brake was engaged, the gear shifter put in neutral, and the clutch pedal pressed
to the floor.
b. The access opening for the clutch assembly was located under the truck just behind the oil
pan. A torch light was used to see where the adjustment plate was.
c. With the clutch pedal depressed, a large flathead screwdriver was used as a lever to rotate the
flywheel assembly till the adjustment plate was at the bottom and fully accessible.
d. Using a socket, only the left-hand bolt which secures the retaining strap was removed.
e. The retaining strap was removed and set aside.
f. Using a wrench, the adjusting bolt on the splined shaft was rotated clockwise (handle towards
the side of the driver) until the proper amount of clutch adjustment was achieved.
g. Reassembling was done and the car was road-tested and found to be functioning properly.
43
Figure 21: The opened clutch system
Figure 22: The removed pressure and clutch plates
44
Panel beating a Pajero Shogun
Panel beating refers to repairing vehicle bodies back to their factory state after having been
damaged. This work is done by an auto-body mechanic called the panel beater. The process is a
highly labor intensive, involving various techniques to remove dents, shape panels to match the
original contours then smooth, resurface and spray paint the damaged areas.
Spraying a car involves applying to the body of the car, a jet of vapor or tiny drops of coating or
paint to make the car look good. The operation is shown in Figures 23 and 24 below.
Reasons for the operation
The operation was carried out in order to:
1. Remove the dents developed during the damage.
2. Prepare the body of the car for spray painting.
3. Bring back the body of the vehicle to the factory state.
Tools and equipment used
Hand hammer, body file, rough sand paper, wooden piece, filler paste, pad, hardener, spot putty,
spraying gun, primer, wooden holder, smooth sand paper, water, undercoat duke metallic paint,
undercoat duke silver, thinner, clear coating, Hacksaw blade, Detergents, ring spanners 14
combined, papers and cellotape.
Safety precautions for the operation
The following are the safety measures that should be observed during the operation:
a. Always use correct spanners when removing the body parts of the vehicle that
is to be panel-beaten and/or sprayed.
b. Great care should be taken when using the hammer to bring back the shape of the body of
the vehicle in such a way that the body is not further damaged.
c. Carefully use the body file as it may hurt the user and also cause further
damages to the part being filed.
d. Always wear protective gears during the operation.
e. Ensure that the vehicle is properly parked.
Technical procedures followed
The following procedures were observed during the operation.
a. The vehicle was parked on a clean, dry, solid surface, the parking brake was applied.
b. The dents on the body parts of the vehicle were identified by visual inspection, where the
damaged parts are surveyed using the eyes, and feeling inspection where the hands are
gently moved on the surface to feel the dented parts.
c. The vehicle was properly cleaned with water and dried with a piece of cloth.
45
d. The hand hammer and piece of cloth were used to bring back the shape of the body of the
vehicle that was damaged, taking care not to disorganize the permanently designed marks
on the body surface of the vehicle.
e. The damaged parts were filed off; properly making sure that the outer coating is also
filed. This was done using the body file.
f. The filler paste was mixed with the hardener in appropriate proportion with the hardener
and then the mixture was applied on the body parts that had been filed. The filler paste
was applied using pads.
g. The parts were left to dry and then were again slightly filed with the body file and then
sanded properly using rough sand paper to smoothen the body surfaces.
h. Spot putty was then applied using a pad so as to fill in the scratches developed during
filing and sanding processes.
i. The parts were left to dry and then were sanded properly with smooth sand paper 500.
While doing so, water was applied frequently. The parts were then again left to dry.
j. The parts that were not supposed to be sprayed were covered using pieces of papers and
mended with masking tape.
k. Using spraying gun, the primer was then applied to the body surfaces, to prevent rusting
from occurring. It was then left to dry.
l. The body was then sprayed with undercoat duke silver using a spraying gun. It was then
left to dry after which it was sprayed with undercoat metallic.
m. Clear coating was then sprayed to the body surface. The clear coating was mixed with
hardener and thinner to make the body surface to shine brightly and look newer.
46
Figure 23: Sanding using smooth sand paper 500
Figure 24: Covering the parts that were not supposed to be sprayed
47
CHAPTER FOUR: SKILLS ACQUIRED, CHALLENGES FACED
RECOMMENDATIONS AND CONCLUSION
Introduction
This chapter covers the skills acquired from the field attachment training, challenges faced at
work, recommendations and conclusion.
Experience gained/achievements from the training
From the industrial training, I acquired a number of skills and knowledge through the application
of the theoretical knowledge learnt in class into the practical operations which led to an
improvement and widening of my engineering knowledge. All activities were carried out while
taking note of all the safety precautions necessary to prevent accidents and produce the desired
results accurately and in time while using the right tools and following the correct procedures.
The following were the achievements from the training.
a.
b.
c.
d.
e.
f.
g.
h.
Maintenance of vehicles and equipment.
Exposure to the demands and challenges of the workplace.
Appreciation of the professional and therefore better work ethics.
Improved confidence in problem-solving.
How to relate to different categories of people likely to be met in real-life situation.
Opportunity to meet and work with potential employers.
Gained first-hand experience working as an engineering professional.
I learnt how to work with other engineering professionals and the value of teamwork in
engineering.
i. I was able to increase my technical, interpersonal and communication skills, both oral
and written.
Challenges faced during the training
During the training, a number of challenges were faced as given below.
a. Most technical words used in motor vehicle work were not familiar to me but more
research and inquiries were made from the senior mechanics and through reading of
vehicle manuals to get acquainted with them.
b. In the earlier days of the training, several accidents and injuries were sustained for
example cuts on fingers and legs; however with time, vigilance on work was increased
which reduced on injuries.
c. Language barrier. The language used at the work place was not familiar to me but usually
requested them to kindly translate for me and also efforts were made to learn the key
words normally used while carrying out operations.
48
d. While making inquiries from the senior mechanics on the operations being carried out,
different reactions would be received from different people; some were welcoming while
others were tough. So most of the research and inquiries were made with the friendly
mechanics and serious efforts were made to befriend everyone at the workshop.
e. Delay of some spare parts of the vehicles which made some work not to be completed
in time.
f. Most of the work needed use of heavy tools and machine components which made the
work difficult, tiresome and time consuming. In such cases, help was sought from other
people in the workshop to help especially in lifting the heavy machine components and
tools.
g. Inadequate tools and equipment like spanners, cylinder head resurfacing machine,
crankshaft regrinding machine, and water jet cleaner which is used to clean the radiator;
caused delay of the work hence creating work backlogs.
h. Unfavorable weather conditions like heavy rainfall often disrupted activities at the
workshop. In such cases, operations were carried out under an erected structure, which
however could only accommodate small vehicles.
i. Relating theoretical knowledge to practical situations was a great setback. However,
through continuous research and persistent inquiries from the workshop technicians, it
became easy.
j. Limited time to share knowledge with all engineers and technicians due to tight schedules
at the workshop.
k. Inadequate financial support to cater for my daily expenses like transport, meals and
others.
l. Limited working space due to congestion in the workshop.
m. Inadequate safety guards during operation of some machines like air compressor which
blows dust from air cleaners.
n. Lack of well-designed training program and an immediate person who is responsible for
the affairs of the trainees. This made trainees not to fully exploit some of the most
important engineering aspects of the institution as there was no serious monitoring and
also access to some of the sections was either not easy or prohibited without the
permission of a supervisor.
o. There was poor sanitation at the workshop. For example, toilets were shared equally by
both male and female workers. This is risky to the health of workers.
p. Too much bureaucracy which led to delay of work in the workshop as sometimes spare
parts and other materials could not be accessed in time.
49
Recommendations
Following what transpired during the industrial training especially the challenges I encountered,
I recommend the following to the management of DCVI.
a.
Proper waste management should be frequently carried out at the workshop. Rubbish
should be collected together and either burnt or disposed off to keep the workshop
clean every time.
b.
There should be a well-designed training program for trainees and an immediate
person responsible for their affairs.
c.
All the necessary tools should be availed and close supervision carried out by
registering all the tools and the corresponding workers using them so that in case of
any tool loss, the particular worker is responsible and replaces them.
d.
More safety gadgets should be acquired especially for air compressing and panel
beating
e.
More air compressors should be acquired so that more air filters can be cleaned
within a short time.
f.
Cleaning air filters should be carried out from an open space where there is free
circulation of air to protect the person carrying out the operation from dust and other
harmful fumes.
g.
Scraps should be removed from working areas to give more working space as well as
for safety purposes.
h.
There should be a scrap yard where scraps are collected and stored.
i.
Management should consider expanding the workshop so as to accommodate the
ever-increasing volume of work at the workshop.
j.
Training duration should be extended since the mechanical engineering field is a very
wide one and therefore cannot be fully exhausted within the allocated weeks of
training.
k.
Materials should be acquired timely and availed immediately upon requisition, to
avoid delay in carrying out work in the workshop.
l.
In a bid to improve sanitation of workers at the workshop, I recommend that male and
female workers should use separate toilets.
Conclusion
The internship was a fruitful experience. Through the application of the theoretical knowledge
into real-life problem-solving situations, I gained a lot of experience especially in the automotive
field. I also got insight into professional practice, learnt how life can be fruitful as well as
challenging under employment; and how to face and deal with these challenges. It was also a
great opportunity for developing personal networking activities and making contacts with
influential people; which is of great value to me as far as my career is concerned. The training
also enabled me to discover my strengths and weaknesses. This further helped me to identify
areas to improve on. In a nutshell, I achieved most of my learning objectives from the training.
50
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