Light

Machinery
Handbook
This handbook cover the additional information a professional driver needs to know when
operating light machinery and should be seen as a complement to the Light Vehicle Emirates December 2018
Driving Company Handbook. Issue v1.0

BOOK
Copyright © 2017 by Emirates Driving Company, Abu Dhabi, United Arab Emirates | www.edcad.ae
5
TABLE OF
CONTENTS
TABLE OF CONTENTS

GENERAL SAFETY RULES 015

1.1 Introduction to Machine Operation  016

1.1.1 Environmental Considerations 017
1.2 Different Types of Heavy Machinery 018
1.3 Different Types of Light Machinery 020
1.4 Different Types of Uses  023
1.4.1 Quarry and Aggregates 023
1.4.2 Building 024
1.4.3 Road Construction 025
1.4.4 Oil and Gas 026
1.5 General Safety Rules 027
1.5.1 Why is safety so important? 027
1.6 Being a Safe Operator 028
1.7 Know Your Machine 028
1.8 Some Important Protective Structures 029
1.8.1 Falling Object Protective Structure (FOPS): 029
1.8.2 Rollover Protective Structure Compartment side structure (ROPS): 029
1.8.3 Operator’s restraints: 029
1.9 Remodeling or Modifying the Machine  030
1.10 Before You Start 030
1.11 Safety Symbol 030
1.12 Safety Decals 031
1.13 Machine Operator’s Responsibilities 033
1.13.1 Machine operator safety 035
1.13.2 Mounting and dismounting from the machine 036
1.13.3 Machine operator environment 037
1.13.4 Guidelines for reducing vibration levels on machines 037
1.14 Ergonomics 039
1.15 Accidents and Health Issues from Work with Machinery 040
1.15.1 Hazards from Falling Materials and Equipment 040
1.15.2 Noise 040
1.15.3 Spine Disorders 040
1.15.4 Visual Problems 041
1.15.5 Exhaust and Fumes 041
1.15.6 Improper Training 041
1.16 Working within dangerous areas 042
1.16.1 High voltage overhead power line  042
1.16.2 Working in confined areas 044
1.16.3 Working near harbor areas 044
1.16.4 Traveling and operating on a public road 044
1.17 Machinery Emergency Procedures 046
1.18 Fire prevention measures 048
1.18.1 In an event of fire 048
1.18.2 Refueling the machine 049
TABLE OF CONTENTS

1.19 Eco-driving 050

1.19.1 The Basic Requirements 050
1.19.2 Eco driving can be divided into three strategies 051
1.20 Load on Trailer 052
1.20.1 Do not become part of a statistic!  052

VEHICLE KNOWLEDGE 057

2.1 Understanding of Internal Combustion piston engines 058

2.1.1 Cylinder block 058
2.1.2 Cylinder head 058
2.1.3 Oil sump 058
2.1.4 Pistons 058
2.1.5 Crankshaft 058
2.1.6 Camshaft 058
2.1.7 Air intake and exhaust manifolds 058
2.2 Two stroke engine 059
2.3 Four stroke engine 060
2.4 Diesel engine 061
2.4.1 Diesel engine pros and cons 062
2.4.2 Cold start device  062
2.5 Air induction 063
2.5.1 Air filter 063
2.5.2 Paper filter 063
2.5.3 Oil bath filter 063
2.6 Turbo charger 064
2.7 Exhaust system 065
2.7.1 Silencer 065
2.7.2 Catalytic converter 065
2.7.3 Particle filter 065
2.7.4 Exhaust pressure regulator (EPR) 065
2.8 Smoking engine 066
2.8.1 Black smoke 066
2.8.2 Blue smoke 066
2.8.3 White smoke 067
2.8.4 Environment and exhaust gases 067
2.9 The fuel system 068
2.9.1 The fuel tank 068
2.9.2 Fuel filters 068
2.9.3 The Fuel pump 068
2.9.4 The injector 069
2.9.5 Electronic fuel system 070
2.9.6 Bleeding the fuel system 071
2.10 Machine’s lubrication system 072
2.10.1 Mineral oil or synthetic oil 073
2.11 Cooling system 074
2.11.1 Air-cooling 074
2.11.2 Liquid- cooling 074
2.11.3 Radiator 074
2.11.4 Cooling liquid 074
2.12 Electrical system 075
2.12.1 Batteries  075
2.12.2 Generator 075
2.12.3 Relays 075
2.12.4 Fuses 075
2.13 Engine Emergency Lamps 076
2.14 Engine oil pressure warning lamp 076
2.15 Battery charge warning lamp 076
2.16 Coolant temperature warning lamp 076
2.17 Air cleaner warning lamp 076
2.18 Machines hydraulic 077
2.18.1 Open center circuits 077
2.18.2 Closed center circuits 077
2.18.3 Hydraulic fluid 078
2.18.4 Filters 078
2.18.5 Tubes, pipes and hoses  079
2.18.6 Reservoir 080
2.18.7 Hydraulic pump 081
2.19 Regular Maintenance 082
2.20 Troubleshooting 083
2.21 Operating’s Physics 084

LIGHT BULLDOZER (SKID STEER DOZER) 089

3.1 Introduction to Bulldozers 090

3.2 The Structure of the Bulldozer 090
3.3 The Operator’s Environment 091
3.3.1 Dozer Control Levers 092
3.4 Bulldozer Attachments 094
3.5 Bulldozer Operators 095
3.6 Training 095
3.7 Performing Maintenance 095
3.8 Before Work 095
3.8.1 Pre-Use Procedures 095
3.8.2 Pre-shift inspection 095
3.9 Operating Precautions 096
3.10 Example Procedural Check-list 097
3.10.1 Start-up and shut down of the machine 097
3.11 Know Your Working Area 098
TABLE OF CONTENTS

3.12 How to Operate a Bulldozer in different situations? 099

3.12.1 Pushing with a Bulldozer Blade 099
3.12.2 Operating Bulldozers in Wet Areas. 101
3.12.3 How to Bulldoze Wet Sand or Mud 102
3.12.4 Operating Bulldozers in Steep Terrain. 103
3.12.5 Operating Bulldozers in Mountain areas 105
3.13 Parking 106

LIGHT WHEEL LOADER (SKID STEER LOADER) 111

4.1 Introduction Light Wheel Loader 112

4.2 Skid steer structure 113
4.3 The Operator´S Environment 114
4.3.1 Operator´s Controls 114
4.4 Difference Between a Wheel Loader & a Skid Loader 116
4.5 Skid Steer Attachments 117
4.5.1 Fitting an Attachment 118
4.5.2 Quick couplers 119
4.5.3 Types of Couplers  120
4.5.4 Operation of Couplers 120
4.5.5 Safety issues with couplers 121
4.6 Operating a Skid Steer Machine 122
4.6.1 Entering and Exiting the Machine 122
4.7 Weight distribution 124
4.8 Before you start the Operations 124
4.9 How to Use a Skid Steer? 125
4.9.1 Basic Operations  126
4.9.2 Techniques for filling, lifting, carrying and emptying load 127
4.10 Leveling and Pushing Operations 130
4.11 Loading a Truck 131
4.12 Pushing with a Dozer Blade 132
4.13 How to load a Skid Steer Without Power? 133
4.14 How to Work in Wet Sand or Mud? 134
4.15 How to Operate Skid Steers in Steep Terrain? 136
4.16 Accident With Skid Steer 138
4.16.1 Major Hazards 138
4.16.2 Hazard Factors 138
4.17 Parking 139
LIGHT EXCAVATOR 143

5.1 Introduction 144

5.2 The Excavator Structure 145
5.3 The Main Controls 146
5.3.1 The Travel Levers 146
5.3.2 Left Travel Lever 147
5.3.3 Right Travel Lever 147
5.3.4 To Make a Spin Turn 147
5.3.5 The Operating Levers 148
5.3.6 Left Operating Lever 149
5.3.7 Right Operating Lever 149
5.4 Machine Attachments  150
5.4.1 General Duty Buckets  150
5.4.2 General Purpose Buckets  150
5.4.3 Ditch Cleaning Buckets  150
5.4.4 Tilting Ditch Cleaning Buckets  151
5.4.5 A tilt rotator (Rototilt)  151
5.4.6 Fitting Attachments (Couplers) 152
5.4.7 CF Mechanical Quick Latch Coupler  152
5.5 Techniques of excavating 153
5.5.1 Prohibited Operations 154
5.5.2 Digging Base Rock 155
5.6 Traveling Over Obstacles 156
5.6.1 Traveling at Higher Speeds 157
5.6.2 Traveling on Sloping Terrain 157
5.6.3 Traveling posture 158
5.7 Excavating  159
5.7.1 Loading a Truck  160
5.7.2 Lifting Load  161
5.8 Procedures and Checklists 162
5.8.1 Starting up your machine 162
5.8.2 After Starting the Engine 162
5.8.3 Sample Excavator Checklist 163
5.8.4 General Precautions 164
5.8.5 Work site Visibility 164
5.8.6 Seatbelts 165
5.8.7 Riders on the Machine 165
5.8.8 Know the Working Area 165
5.8.9 Overhead Clearance 166
5.9 Excavator Hand Signals 167
5.10 Parking the Machine 168
5.10.1 Engine Shutdown 168
5.10.2 Parking  168
5.10.3 Before leaving the cab 169
TABLE OF CONTENTS

LIGHT ROAD ROLLER 173

6.1 Introduction  174

6.2 Machine structure 174
6.3 Instruments and controls 175
6.4 Types of Rollers 176
6.4.1 Single Drum Roller 176
6.4.2 Tandem Asphalt Rollers 176
6.4.3 Vibratory Steel Wheel Rollers 177
6.4.4 Pneumatic Tire Rollers 177
6.4.5 Three-Point Rollers  178
6.4.6 Pad Foot Drum Roller 178
6.5 Vibration button 179
6.5.1 Vibratory amplitude 179
6.6 Techniques for Rolling 180
6.6.1 How to Roll an Asphalt Mat? 180
6.6.2 How to Roll an Asphalt Mat behind the Paver? 181
6.7 Operating on sloping ground 183
6.7.1 Maximum machine tilt angle 183
6.8 Procedures and Checklists 184
6.8.1 Test controls 184
6.8.2 Sample Checklist 185
6.8.3 Know the Working Area 186
6.8.4 Danger Zones 186
6.8.5 Pivot area 186
6.8.6 Overhead Clearance 187
6.9 Roller Hand Signals 188
6.10 Machine shut down  189

LIGHT CRANE (TRUCK MOUNTED CRANE) 193

7.1 Introduction 194

7.1.1 Background 195
7.2 Machine structure 197
7.3 Crane controls 198
7.4 Crane Attachments 200
7.5 How to operate the crane? 201
7.5.1 Basic Conditions 201
7.5.2 Location of crane 202
7.5.3 Out riggers 203
7.5.4 Begin Lifting 204
7.6 Control at coupling and strapping 205
7.7 Lifting accessories Safety precautions 205
7.7.1 Wire Rope Precautions 206
7.7.2 Marking 208
7.7.3 The bending diameter impacts on the maximum load 209
7.7.4 Unbalanced load 209
7.8 Lifting 210
7.8.1 Not allowed!  211
7.9 Moving the crane at the worksite 212
7.9.1 Moving a crane on a public road 213
7.9.2 Coordination  214
7.10 Signalman 215
7.10.1 Hoisting Hand Signals 216
7.11 Personal lift 217
7.12 Locking of the crane 218

LIGHT FORKLIFT 223

8.1 Introduction 224

8.2 Basic Components of a Forklift 225
8.3 Operator’s Environment 226
8.3.1 Controls &Instrument panel 226
8.4 Operating Controls 227
8.5 Operator’s Restraints 228
8.5.1 Seatbelts 229
8.5.2 If the forklift overturns! 229
8.6 Preparation 230
8.6.1 Forklift Pre-Use Checklist  230
8.7 Starting the engine 232
8.7.1 The Machine Operation 232
8.7.2 How do forklifts safely carry and lift heavy loads?  232
8.7.3 Forklift Safety Features 232
8.8 Safe Operation 233
8.8.1 Center of Gravity and Load 233
8.8.2 How the weight is divided on the forklift? 233
8.9 Stability Triangle 234
8.10 Moving on Slopes 235
8.11 Machine Requirements 236
8.12 Operating Forklift in different working sites  237
8.13 Accidents 239
8.14 Safety during Operation 240
8.14.1 Forklift, Operator and Load Safety 240
8.14.2 Precautions 240
8.15 Signal man 241
8.16 Load Capacities 242
8.16.1 Picking up the Load 242
8.17 Load Stability  243
8.17.1 Key Risks to Forklift Stability 243
TABLE OF CONTENTS

8.18 Managing Rollover Risk for Forklift Operators 244

8.18.1 Stacking 244
8.18.2 Operating a Forklift safely  244
8.18.3 Setting down a load 245
8.19 Speed Limit and Braking Distance  246
8.19.1 Speed limit: 246
8.19.2 Braking Distance 246
8.19.3 Minimum Actual Emergency Stopping Distance 246
8.20 Duties of self-employed persons  247
8.20.1 Duties of supervisors  247
8.20.2 Abilities, Duties and Qualifications of the Operator 247
8.20.3 Duties of Employers 248
8.21 Health Management during operation 249
8.21.1 Poorly Ventilated Workplaces  249
8.22 Precautions & dangers 250
8.23 Forklift Maintenance 251
8.23.1 Precaution before maintenance 252
8.24 Shut down procedures 253
Chapter One
GENERAL SAFETY
RULES
1.1 Introduction to Machine Operation

In all machine operations, it is important that the machine operators are well trained on their
machine and is familiar with the risks that may arise when operating the machine. To operate
the machine properly, it is important to be very familiar with all of the machines functions. This is
key to ensure your safety, the safety of others and the safekeeping of the machine.

Communication with supervisors and other personnel involved in a project is necessary to

ensure that there are no misunderstandings in the work site.

The machines should only be used under normal conditions, specified in the machine manual.

1.1.1 Environmental Considerations

Be aware of potential dangers to the environment at all times. Oil degrades very slowly in
Take proper care and maintain the machine. water and sediment.

Be environmentally conscious when carrying out service and One liter of oil can destroy
maintenance. Spilled oil and other liquids are dangerous to the millions of liters of
environment and will cause damage. drinking water.

016 General Safety Rules

1.2 Different Types of Heavy Machinery
Wheel loader

A wheel loader is heavy mechanical equipment widely used on construction sites for Leveling,
Pushing, Loading or Transferring of material like:

• Soil • Asphalt • Sand and

other lose or
• Gravel • Demolition packed material
wreckage

Excavator

Excavators are earth-

moving equipment’s
used for the purpose of
excavation, loading and
lifting light loads.

It can also use crusher,

hammer or shear for
performing quarry
and demolition.

Maintain the
machine.

General Safety Rules 017

1.2 Different Types of Heavy Machinery
Bulldozer

A bulldozer is heavy mechanical equipment widely used on construction sites. It is for removing
and filling, excavation, planning or transferring materials like:

• Stone

• Rocks

• Soil

• Gravel

• Asphalt

• Demolition
wreckage

• Sand and
other lose or
packed material

Heavy crane

A mobile crane is heavy mechanical equipment widely used on construction sites. It is for lifting
or transferring material like:

• Concrete

• Armor

• Soil

• Building
materials

• Prefabricated
Construction
elements

• Bulky Equipment

018 General Safety Rules

Heavy Forklift

Heavy Forklifts are powered

trucks intended to lift and
transport materials for
short distances, normally
by means of steel forks
inserted under the load
stored on pallets.

Industrial and warehouses

consider a forklift as
indispensable equipment
that is essential for
their operations.

Heavy
Forklifts are
powered
trucks.
Heavy Road Roller

A road roller is heavy

mechanical equipment widely
used on construction sites.

It is a compactor type-
engineering machine used
to compact soil, gravel, or
asphalt in the construction of
roads and foundations.

Similar rollers are also used

at landfills.

A road roller
used on
construction
sites.

General Safety Rules 019

1.3 Different Types of Light Machinery
Light Wheel Loader (Skid Steer Loaders)

Skid steer loaders are light mechanical equipment widely used on construction sites, especially
inside cities where there are tight spaces and areas of land that cannot withstand high weights.

It can be used for Leveling, Pushing, Loading or Transferring of material like:

• Soil

• Gravel

• Asphalt

• Demolition
wreckage

• Sand and
other lose or
packed material

Light Excavator (Backhoe)

A backhoe loader is mechanical equipment used on construction sites. It is for digging/loading

or transferring materials like:

• Soil

• Gravel

• Asphalt

• Demolition
wreckage

• Sand and
other lose or
packed material

020 General Safety Rules

Light Bulldozer (Skid Steer Dozer)

A skid steer dozer is light mechanical equipment widely used on construction sites, gardens or
parks. It is for excavation, planning or transferring material like:

• Stone

• Rocks

• Soil

• Gravel

• Sand and
other lose or
packed material

Light Crane (Truck Mounted Crane)

A truck-mounted crane is mechanical equipment widely used on construction sites. It is for

lifting or transferring material like:

• Concrete

• Armor

• Soil

• Building
materials

• Prefabricated
Construction
elements

• Bulky Equipment

General Safety Rules 021

1.3 Different Types of Light Machinery
LIGHT FORKLIFT

Light Forklifts are powered trucks intended to lift and transport materials for short distances,
normally by means of steel forks inserted under Loaded pallets. Industrial and warehouses
consider a forklift as indispensable equipment that is essential for their operations.

LIGHT ROLLER

A road roller is mechanical equipment widely used on construction sites. It is a compactor type-
engineering machine, used to compact soil, gravel, or asphalt in the construction of roads and
foundations. Similar rollers are also used at landfills or in agriculture.

022 General Safety Rules

1.4 Different Types of Uses
1.4.1 Quarry and Aggregates

1. Investigation 6. Drilling/ 10. Crushing

and planning charging and screening
and blasting
2. Transport 11. Re-handling and
of equipment 7. Digging/ stockpiling
primary loading
3. Preparation 12. Loading for
of areas 8. Digging/ distribution
oversized
4. Harvesting/off- stone handling 13. Work site
road transports maintenance
9. Loading/
5. Stripping/ transporting 14. Restoration
removal of to crusher of the site
overburden

Stripping / Removal
of overburden
5
3
1 Preparing
Equipment
Investigation access
transport
& planning 2

13
Site
Drilling, charging maintenance
and blasting Loading / Transport 14
6
4 Face to crusher Site reclamation /
Harvesting / 9 Re-instatament
Off road transport
Crushing &
Digging / Oversized
Screener
Stone handling 10
8
7
Digging /
Primary loading

Loading for
12 distribution

11
Rehandling /
Stockpilling

General Safety Rules 023

1.4 Different Types of Uses
1.4.2 Building

1. Investigation 4. Ground 8. Work site clean

and planning reinforcement up/repair and
maintenance
2. Forest harvesting 5. Deep ditches
removal of 9. Reinstatement/
overburden 6. Foundations landscaping

3. Mass excavation 7. Building

Forest harvesting /
Removal of overburden
2

1 8
Investigation
Site clean up /
& planning
Repair and maintenance
8

Foundations
6

Mass 3
excavation

7
Building

Deep
5
utilities

Reinstatement
landscaping
9

4
Ground
reinforcement

024 General Safety Rules

1.4.3 Road Construction

1. Investigation 3. Testing and 5. Reinstatement/

and planning backfilling landscaping

2. Excavation 4. Final grading 6. Work site clean

light and up/repair and
shallow utilities maintenance

1
Investigation
& planning Testing &
backfilling
4 5

Site clean up /
Repair and maintenance
8

Final grading
6

Reinstatement
landscaping
7

Excavation /
Light & shallow
utilities
2 3

General Safety Rules 025

1.4 Different Types of Uses
1.4.4 Oil and Gas

1. Equipment 5. Bending and setup 10. Lowering in

delivery, (pipes in trenches)
material delivery 6. Welding
11. Tie ins
2. Opening/clearing 7. Pipe induction/
the right of way heating and coating 12. Backfilling

3. Pipe unloading 8. Trenching 13. Reinstatement

restoration/
4. Stringing 9. Preparing planting
the pipe bed

1b
Material
delivery
3
Pipe
unloading

Grooming
2 Opening / 16
clearing the right of way Reinstatement restoration
/ planting
17 18
14 15
Backfilling
& testing

Backfilling
& testing

Lowering in
12

Bending & Tie-ins

13
Set-up
Pipe Induction Heating
5 6
& coating (PIH)
9
Preparing the
pipe bed 7 8
11 Bevelling /
Trenching
Welding
10

4
Stringing
Equipment
1a delivery

026 General Safety Rules

1.5 General Safety Rules
This part contains rules, which you must follow to ensure safety. Please note that these rules
do not relieve the operator from following laws or other national regulations for traffic safety,
industrial safety and labor welfare.

In order to avoid the risk of accidents, being alert, having sound judgment and complying with
safety regulations is must.

1.5.1 Why is safety so important?

• Accidents can lead • Accidents can take • Keeping safety in

to major physical a massive financial mind, accidents can
injuries, permanent and emotional toll on really be avoided.
disability, or all those involved.
even death.

Observe all Safety Rules

As with any light machinery, it is of utmost importance to know and follow the general safety
precautions for operating a machine.

Some of the most important precautions are as follows:

• All rules, set machine under filter mask,

of laws, safety the influence of heavy gloves, ear
measures and alcohol, medicine protection and
safety procedures or other drugs. other protective
must be known, equipment as
understood and • Only a trained, required by the
followed when experienced job and site
performing and qualified conditions.
operation, person must
inspection and carry out tasks • Use hearing
maintenance of like operation, protection when
the machine. inspection and operating the
maintenance of machine. Loud
• The machine the machine. prolonged noise
operator must can cause hearing
be thoroughly fit • Wear a hard hat, impairments, and
and must never safety shoes, even the total loss
operate the safety glasses, of hearing.

General Safety Rules 027

1.6 Being a 1.7 Know Your Machine
Safe Operator
Know everything through; be sure you have read the
• You must be manufacturer’s operator manual thoroughly before you start
a qualified your engine.
and licensed
operator in order If there is no manual with the machine, then get one!
to operate an
excavator. If there is something in the manual you do not understand, ask
your supervisor to explain it to you.

• You must If your machine is equipped with other devices or special

understand accessories, be sure to read the operating and safety manuals
the written from the manufacturer pertaining to that specific equipment
instructions before using it.
supplied by the
manufacturer.

• You must have

proper training.

• You must know

all the safety
rules applicable
to the work site
thoroughly.

• You must not

use drugs or
alcohol that
may impair your
alertness or
coordination.

• An operator on
prescription or is
taking over-the-
counter drugs
needs medical
advice regarding
whether or
not he can
safely operate

Know everything through.

machines.

028 General Safety Rules

1.8 Some Important Protective Structures

Modern machineries are equipped with safety mechanisms called protective structures that are
designed to protect the operator in case of an accident.

We will learn more about safety measures in the next section, but here is what you need to know
about the various types of protective structures:

1.8.3 Operator’s
1.8.1 Falling Object 1.8.2 Rollover Protective restraints:
Protective Structure
Structure (FOPS): Compartment side
structure (ROPS):

This structure is an overhead This structure refers to Operator restraints will hold
guard that prevents an object operator compartment the operator onto the seat if
from falling onto the operator structures intended to the machinery overturns or
during operation. The guard protect the equipment strikes any object. Failure to
is not designed to withstand operators from injuries wear the restraint can result in
the impact of heavy loads, caused by equipment the operator being thrown out
though it is effective against overturns or rollovers. of the operator’s compartment
light objects. It is a required in the event of an overturn. If
structure on all machinery your Machinery machine has a
restraint such as a seat belt or
a lap bar, you must use it.

Modern machineries are equipped with safety

mechanisms called protective structures that
are designed to protect the operator in case of
an accident.

General Safety Rules 029

1.9 Remodeling or Modifying the Machine
You must also not remove
any safety equipment from
• Never remodel • Machine operator the machine. Make sure that
or modify the or the owner all protective guards, shelter,
machine without must keep in doors, etc., are in place and
the manufacturer’s mind that any secure. Repair or replace
or traffic accident caused damaged components before
department’s by remodeling beginning operations. You
permission. or modifying the should know where the safety
machine means lock lever, seatbelt and other
• Remodeling or that the insurance safety equipment are located
modification that is companies or the and how to use them properly.
not recommended manufacturers
will lower safety, will not bear any Never remove any safety
invite danger, responsibility equipment except for
deteriorate the for the service, as the results
functions of the resulting damages. can be devastating or
Machine and sometimes even deadly.
shorten its life.
Keep all safety equipment in
good operating condition.

1.10 Before You Start

Before you begin working, it is important that you know who is responsible on the work site and
to whom you should speak for any question and concern.

The site manager is most often responsible for a construction site, under him a number of
supervisors. Supervisors will manage people with different roles, such as machine operators.

1.11 Safety Symbol

This symbol means “pay Follow the safety instructions given in the operator’s manual
attention!” The safety alert and on the machine itself.
symbol signifies important
safety messages and can
be found on instruments,
machines or elsewhere.

When you see this symbol,

be alert to the possibility
of serious injury that
could lead to permanent
disability or death.

030 General Safety Rules

1.12 Safety Decals
This signal word signifies an immediate hazard, which, if not taken care of may cause death or
severe injury. This signal word is to be limited to the extreme situations, typically for machine
components that, for functional purposes, cannot be guarded.

1.12.1 Different Types of Safety decals

IMPORTANT

This signal
This message is used when special precautions should be taken
to avoid damage to, or malfunction of, the machine.

The manufacturer specifies word

signifies
the type of fuel that should
be used in the engine.

an immediate
hazard.
WARNING

This message is used when a hazard exists which can result in injury or death if proper
precautions are not taken.

This sign is for people This is a warning for the operator and/or the workers around
working around the machine the machine to know that the engine is hot.
to keep away from the
machine swinging area.

General Safety Rules 031

1.12 Safety Decals
CAUTION

This message is for proper precautions, which, if not followed, can result in personal injury.

Keep hands, arms and whole Go through the operation The operator must switch off
body away from hot surfaces. and service manual before the engine before opening the
operating the machine to lid or hood of the engine.
avoid danger/risk of injury.

DANGER

This message is used when an extreme hazard exists which will result in death or serious injury.

To prevent injury, make sure Keep your hands and body away from any electrical parts as they
the engine is shut off prior are under high voltage.
to working on any part of the
engine compartment.

032 General Safety Rules

1.13 Machine Operator’s Responsibilities

• While working be used in contact • The machine

with machines, with objects or operator must be
you need to set up at temperatures thoroughly familiar
roadblocks and in excess of 194 with how to operate
keep an eye on degrees F (90 and maintain
the surroundings degrees C), or the machine. He
while you work. below minus 40 should preferably
degrees F (minus undergo the
• Drive slowly when 40 degrees C). required training
maneuvering Because it will for the machine
in tight spaces reduce the value
or when driving of strain carrying • The machine
over bumps. The strength of operator must
synthetic webbing follow the rules and
• Keep the load and slings can be recommendations
the attachment degraded by outlined in
in a low position chemically active the Operator's
in order to have environments . Manual, while
forward visibility. simultaneously
• The machine paying attention
• Check that the operator must to any statutory/
equipment you are operate the national
using for lifting or machine in such a regulations
supporting parts way, that the risk that apply.
of the machine of accidents is
are applicable minimized for the • The machine
(E.g. straps, slings, operator, other road operator is
ratchet blocks and users and persons responsible for
ground support) present at the the load and the
and safely cope work site. machine, both
with the strain they
are exposed to and
that they meet the
applicable national
regulations and
instruction.

• Slings and
straps must be
periodically tested.
Loading label and
plates must be
with slings and
straps. Do not
allow nylon and
polyester slings to

General Safety Rules 033

1.13 Machine Operator’s Responsibilities

when traveling on to the center danger area, (i.e. A

public roads as well of gravity. distance of at least
as when working 7 m (23 ft.) in all
on the site. • The machine directions from an
operator must be operating
• There must be no in charge of the machine).
risk of the load working area of
falling off while the machine. • The operator
operating. You may allow only
must refuse the • Prevent persons necessary persons
load when it is an from walking or to remain in the
obvious safety risk. standing under the danger area, but
raised lifting arms; should then observe
• Respect the rated the area should caution and operate
load capacity of be secured. the machine only
the machine. when the person is
• Prevent persons visible, or has given
• Note the effect of from entering or clear indications of
varying distances remaining in the where he or she is.

034 General Safety Rules

The machine operator may allow an instructor on board only if there is an approved passenger seat.

1.13.1 Machine operator safety

• The machine Never use a when starting

operator must mobile phone the engine.
be thoroughly fit while operating
and must never the machine. • Keep your hands
operate the Always refer away from areas
machine under to the machine where there is a
the influence manual to ensure risk of injury, (e.g.
of alcohol, that the mobile Doors, Covers,
medication or telephone does and windows).
other drugs. not interfere
with important • Always use the
• Suitable clothing electronics. lap belt or the
for safe handling three-point belt,
and a hard hat • Always sit in the if the machine is
should be worn. operator seat equipped with it.

General Safety Rules 035

1.13 Machine Operator’s Responsibilities
1.13.2 Mounting and dismounting from the machine

• Do not jump and maintain • Never

on or off three-point manipulate or
the machine. contact with set the safety
the handrails lock out of
• When mounting and steps, functionality.
and dismounting while getting
the cab, first on and off the • Align the
open the door to machine. Keep cab with the
the fully locked the steps and undercarriage
position and platform clean in the centerline
make sure it and dry to before you stop.
does not move avoid slippage.
during operation. • The door must be
• Avoid contact closed when you
• Always face the with machine are operating the
access system controls . machine.

036 General Safety Rules

1.13.3 Machine 1.13.4 Guidelines for reducing vibration
operator levels on machines
environment

A number of factors, such Use the proper type and size of machine, with optional
as the working mode, equipment and attachments for the application.
ground conditions, and
speed, affects whole-body Keep the terrain and haul roads in good condition.
vibration emissions on
construction machinery.
• Remove any large • Provide equipment
Largely, the operator rocks or obstacles and schedule time
can influence the actual to maintain terrain
vibration levels, because the • Fill any conditions.
operator controls the speed ditches and holes
of the machine, its working
mode, and the travel path.

Therefore, the result can be

a range of different vibration
levels for the same type of
machines, depending on
who is driving.

Use the
proper
type and
size of
machine,
with optional
equipment
Adjust the speed and travel path to minimize the
vibration level

and
attachments
• Drive around • Reduce the
obstacles and speed when it

for the
rough terrain is necessary
conditions. to go over

application.

General Safety Rules 037

1.13 Machine Operator’s Responsibilities
Guidelines to reduce Keep the seat maintained and adjusted.
vibration emissions on
construction machinery:
• Adjust the seat seat suspension
Maintain machines and its suspension and adjustment
according to the according to the mechanisms.
manufacturer's weight and size of
recommendations. the operator. • Use the seat
belt and adjust it
Check: • Inspect and correctly.
maintain the

• Tire pressures. Steer, brake, accelerate, shift gears and move the attachments
smoothly. Minimize vibrations for long work cycles or long
distance traveling.
• Brake
and steering
systems. • Use suspension • Transport
systems if machines when
available. there are long
• Controls, distances between
hydraulic system • If no suspension work sites.
and linkages. system is available,
reduce speed to
prevent bouncing.

038 General Safety Rules

1.14 Ergonomics
Ergonomics means the science of people at work, i.e. the postures and body burdens you face.
Back pain associated with whole-body vibrations may be caused by other factors.

The following guidelines can be effective in minimizing the risk of back pains.

• Adjust the seat • Take breaks to handling and

and controls to a reduce long periods lifting of loads.
good posture. of sitting.
• Maintain a
• Adjust the mirrors • Avoid jumping down reasonable weight
to minimize a from the machine. and good physical
twisted posture. condition.
• Minimize repeated

General Safety Rules 039

1.15 Accidents and Health Issues from Work with Machinery
Unfortunately, operating machinery can sometimes be accompanied by health issues.
There are also some common accidents that can occur on a construction sites, as follows:

1.15.1 Hazards from 1.15.2 Noise 1.15.3 Spine Disorders

Falling Materials
and Equipment

This is the major cause Machines are usually The constant vibration from
of death among heavy powered by high-output the machines can cause
equipment operators. diesel engines and can Whole Body Vibration (WBV),
generate a great amount which is a transmission of
The worker on the of noise. This can cause mechanical vibration from
ground may be struck by damage to the operator's vibrating equipment through
heavy equipment when hearing abilities, as well as a supporting surface to the
it is changing direction create dangerous situations body. These vibrations could
or backing up. on job sites when more than be high-frequency vibrations
one person is present. from transmissions and
The operator of the heavy engines, low-frequency
machine might be caught in Any time a user is operating vibration from the tires and
equipment when the brakes a machine on a job site, terrain, and shock from
are not set properly, or the hearing protection along running into obstacles
worker might be run over with a radio communication or potholes. Long-term
when the equipment is left in device should be worn so exposure to this vibration can
gear or chocks are not used that accidents don't occur result in lower back disorders
to wedge the equipment. involving people working such as disc herniation, an
around the machine. acceleration of degenerative
changes in the spine,
abdominal pain and nausea.

An operator
of heavy
equipment
must
always be
watching
his
environment.

040 General Safety Rules

1.15.4 Visual Problems 1.15.5 Exhaust 1.15.6 Improper
and Fumes Training

An operator of heavy Because of the design of most For the most part, Machines
equipment must always be of the machines, operators are easy to operate, but it
watching his environment. often have to sit extremely is much more important to
He is on the lookout for close to the engine. This can learn to operate them safely.
people who may be in the cause health problems if the
path of the moving machine; machine is driven frequently Improper training on a
monitoring changes in the because diesel engines can machine can result in the
environment; and watching produce harmful exhaust unsafe operation of the
out for underground utilities, and fumes, which are often machine, causing it to
obstacles, overhead power- inhaled by machine operators. either tip over or making the
lines and site traffic. load unstable.

These workers also have to

contend with poor visibility
from the cab and reduced
visibility in winter conditions,
rainy weather and glaring
sunlight on excessively
bright days.

All of these take a toll on the

operators, which can lead to
both mental and eye strain.

The strain can cause the

operators to make mistakes
if they do not take breaks
to rest their eyes and give
themselves a chance to
recharge their mental
batteries. Eye strain can
also cause long-term
sight impairments.

The strain
can cause
the operators
to make
mistakes.

General Safety Rules 041

1.16 Working within dangerous areas
The risks usually involved in Electric cables should, if possible, have the power turned off.
these places.
Information about where the gas and water can be turned off
should be made visible available, so that they can be quickly
• If you work switched off if they are damaged.
with quarry and
aggregates NOTE! If digging has to be carried out very close to cables,
pipes or overhead wires, it may be necessary to dig by hand.
• Working with new
building or maybe
renovation of 1.16.1 High voltage overhead power line
old buildings
Be cautious when working in proximity with high voltage
• Dangerous work overhead power lines, as electrical flash-over may damage the
with oil and gas machine and injure the operator.

• Harbor areas Keep in mind:

can also be
dangerous The distance sideways between the machine and power
places line must be:

• Working within
areas where • At least 2 m in case • 6 m in case of
there are pipes, of low voltage. high voltage
power lines above 40 kv (line
or cables. • 4 m in case of normally carried
high voltage. At on suspended
the most 40 kv insulators).
lines (line normally
It is the duty of the supported on fixed
employer to know and mark insulators).
the position of pipes for
gas, water, sewage, power
lines, or cables on the
work site and to inform the
operator of their positions.

Failure to do so may have

legal consequences.

When required, local

authorities and power
companies should be
contacted regarding maps,
drawings and general advice.
Cables and power lines must
be protected against damage
in the appropriate way.

042 General Safety Rules

The distance vertically between the machines and the overhead power line must be:

• At least 2 m in case of low voltage. • 4 min case of high voltage.

The safety distances to a load must also be kept. Limiting the lifting height with the boom may
be required. The boom (lifting height) may have to be adjusted.

What to do if the machine contacts live power lines:

• Do not panic. • Try to move the inform the power

machine until supply authority
• Stay inside it is clear of and have the power
the cabin. the power lines disconnected.
without anyone
• Warn all other approaching. • Take no action
personnel to keep until it has been
clear from the • If the Machine confirmed by the
machine and not to cannot be moved, authority that
touch any part of stay inside the conditions
the machine. cabin. If possible, are safe.
get someone to

If you must leave the cabin because of fire or other reasons, take the following action:

• Jump clear as far • When moving away • Avoid large steps

as possible from from the machine, because one foot
the machine. the operator should could be in a high
shuffle or hop voltage area and
• Do not at any time slowly away from the other foot in a
make contact with the Machine across low voltage area
the machine and the ground area that could cause a
the ground at the is energized with large amount of
same time. live power. current to flow,
which under some
circumstances,
could be fatal.

The danger when dismounting is that you may make contact with the “live”(high potential) machine
body and the earth(almost 0 potential) at the same time, electricity flows from high to low potential
area causing the electricity to pass through you, which can result in death or severe injury.

Have the machine checked by a competent person for damage prior to further use.

General Safety Rules 043

1.16 Working within dangerous areas
1.16.2 Working in 1.16.3 Working near harbor areas
confined areas

Check that there is sufficient Be cautious in marked danger areas.

room for the machine and
the load. Move slowly. Do not operate too close to the edge of a harbor or ramp.

1.16.4 Traveling and operating on a public road

As a machine operator, you

are considered a road user
and therefore are required to
know and follow local and
national regulations.

It is important to keep in
mind that the machine
compared with the rest of
the traffic, is a slow moving
and wide vehicle, which
may cause obstruction.
Therefore, pay attention
to the traffic behind you.
Facilitate overtaking.

The use of a SMV-plate

(Slow Moving Vehicle) is
recommended. It should be
SMV-plate
placed in a position at the (Slow Moving Vehicle)
rear of the machine where
it can be clearly seen. It
should be positioned at a
height of 0.6–1.8 m (above
the ground, measured from
the lower edge

044 General Safety Rules

Traveling on public roads Operating on a public road

When traveling on public Use Road signs, traffic-restricting arrangements and other
roads, the attachment should safety devices, which may be required when considering traffic
be empty, lowered to the speed and local conditions. When moving a machine with a
carrying position (30–40 cm suspended load, take extra caution.
above the ground) and tilted
fully backward. The front When required, assign a signalman. A rotating warning lamp
end of the material handling (BEACON) may be used:
arm must be marked
with a red flag.
• On a machine during road maintenance work, e.g.
Make sure that the large sand clearing.
attachments/buckets do
not obscure the traveling • On attached or connected equipment, that is wider
lights. According to traffic than the machine itself.
regulations, the area in
front of the machine • When the machine constitutes a hindrance or
must be sufficiently danger to other traffic.
illuminated and visible.
• When working on or by the side of the roadway.
Additional attachments such
as buckets, spades, and iron
bars must be thoroughly
secured with tensioning
straps or chains.

A trailer, or something similar

may be used temporarily
on public roads and then to
transport supplies for the
operation of the machine
(attachments, tools,
fuel, oils etc.).

General Safety Rules 045

1.17 Machinery Emergency Procedures
The following are examples of possible emergency situations. The list of guidelines may vary
with each individual situation.

Rolls Over the Edge Becomes Hung-up On Edge of Stockpile

of a Stockpile

• Stay inside the • Stay inside the cabin.

cabin until the
wheel loader • Apply the parking brake or emergency
will come to a brake.
full stop.
• Call for assistance.
• Await assistance.

Slips into a Cone or Brake Failure on Steep Steering Failure

Hole When Pushing Ramp or Road
Up a Stockpile

• Stay inside • Lower the • Stay inside

the cabin. attachment to the cabin.
the ground and
• Switch off use it as a brake, • Apply the foot
the engine. if necessary. brake and the
emergency
• Call for • Bring the brake.
assistance. machine
to a stop. • Bring the
• Give your exact machine
location when • Stay inside to a stop.
calling for the cabin.
assistance. • Lower all
• Apply equipment.
the emergency
Rolls Over or Partially brake. • Chock
Rolls on a Slope the wheels.
• Chock
the wheels. • Place an Out
• Stay inside the of Service
cabin until the • Place an Out of tag on
machine comes Service tag on the machine.
to a full stop. the machine.
• Report
• Call for • Report the problem.
assistance. the problem.

046 General Safety Rules

Stalls on Steep Ramp or Road Begins to Side Slip on a Grade

• Immediately • Place the bucket

• Stay inside dispose of on the ground to
the cabin. the load. act as a brake.

• Apply the • Turn the shovel

foot brake downhill.
or emergency
brake.

• Bring the Ruptures a Gas Line

Machine
to a stop.
• Stop the machine. • Notify the
• Lower all appropriate
equipment. • Turn off the authorities.
machine.
• Attempt to re- • Keep the area clear
start the engine. • Evacuate of any personnel.
the machine.
• Chock
the wheels.

• Place an Out of
Service tag on
the machine,
if required.

• Report the
problem.

Give your
exact
location
when
calling for
assistance.

General Safety Rules 047

1.18 Fire prevention measures
There is always a risk of If the machine is to be The effectiveness grade
fire. It is important that you provided with a hand- I means that the time the
use a fire extinguisher that held fire extinguisher, it extinguisher is effective
suits your machine and should be of the ABE type must not be less than 8
working environment, and (ABC type in the USA), seconds; grade II at least
importantly, that you learn which means that it is 11 seconds; and grade III at
how to use it. possible to extinguish least 15 seconds.
fires in both solid and
The fire extinguisher should liquid carbonaceous A hand-held fire extinguisher
be placed under the seat material and that the ABE I (ABC type in the USA)
bracket or in an external active compound does not normally corresponds to a
lockable box. conduct electricity powder content of 4 kg.

1.18.1 In an event of fire

At the slightest sign of fire, take the following steps:

• Drive the machine • Leave the cab.

away from the fire.
• Turn off the battery
• Lower the lifting disconnect switch.
arms to the ground.
• Start putting out
• Switch off the engine the fire and notify
the fire brigade/
department if
necessary.

048 General Safety Rules

1.18.2 Refueling the machine

It is preferable to fill up the fuel tank at the end of the working day in order to prevent
condensation of water in the tank (Changes the air fuel ratio) which affects the function.

Refueling should be done as follows:

It is forbidden to smoke
• Shut off the engine • Before leaving the or have an open flame
and remove the machine, check near a machine when re-
ignition key. for any oil or fuel fueling or when the fuel
leaks and for system has been opened
• If the machine is any damages to and is in contact with the
fitted with a master the machine. surrounding air.
switch, shut it off.
• Check engine oil Diesel fuel is flammable
• Make sure that the level, hydraulic fluid and must not be used
fueling area is free level and coolant as a cleaning agent. Use
from any flames, to get the machine approved solvent, but avoid
glows or sparks. fit for the next breathing in the fumes.
day’s use.
• Avoid fuel spill Keep in mind that certain
on hot areas on • If there are any solvents can cause skin
the machine. problems, you rashes and constitute
should report it to a fire hazard.
the supervisor.
Ensure gas is kept in a cool
and ventilated area.

The gas should not be used

on machines with electric
preheating of intake air.

It is
preferable
to fill up the
fuel tank at
the end of
the working
day.

General Safety Rules 049

1.19 Eco-driving
Fossil fuel called a finite A culprit in the climate This will reduce
resource. It has been change debate is considered costs for fuel, service
formed in the subsurface the greenhouse gas CO, and maintenance,
over millions of years produced by the combustion and offers reduced
and it will take millions of fossil fuels. An easy way environmental impact.
more years before the to reduce global warming
corresponding amount is to reduce emissions This is largely a matter
has been established through Eco-driving. of attitude and approach,
again. Therefore, we and a matter of how we
should not consume the Management has a major can motivate operators
earth's finite resources responsibility to ensure and employees to be more
unnecessarily. eco-driving. environmentally conscious.

1.19.1 The Basic Requirements

• The machines run and efficient and maintained.

on eco-grade fuel. particle filters.
• The cab is fitted
• The machines have • The machines are with a clean
a catalyst converter regularly serviced cabin filter.

In order to run sparingly, both the hardware and operators must be in good condition. The
machine must have the proper service and maintenance, the engine must be set correctly, the
controls must operate smoothly, riding position must be right, cab climate should be pleasant
and visibility must be good.

As an operator, you need to be fit and must have an interest in being good at eco-driving

120
Output Fuel
kW 110 g/kWh

100
Output Torque
900
90
700 80

500 70 220

60 210
300
200
Fuel
Torque
Nm
1000 1200 1400 1600 1800 2000
Engine r.p.m.

050 General Safety Rules

1.19.2 Eco driving can be divided into three strategies

Planning Methodology Driving

Means the machine must Means that you should have Means that you need to drive
be properly prepared, that an overview of the work so that you get a good "flow"
you have completed the site so you can run quietly, at work when the machine is
tasks carefully and that without any unnecessary operated at a low speed, with
the equipment and work stops or unexpected soft interfaces, which make
surfaces are ready. acceleration. driving more comfortable,
without excessive noise or
Planning also means You should run right excessive vibration
that you have enough from the beginning to
time available to work avoid repetitions or
without stress. unnecessary movement

General Safety Rules 051

1.20 Load on Trailer
To load the machine onto a trailer for transport by road, involves collaboration between the
truck driver and machine operator.

The important thing is that the truck driver gets as close as possible to the machine area, and
ensures that the surface is hard enough to avoid problems when loading.

Then the machine operator receives instructions so that the machine is correctly loaded on a
trailer and stays within the law when it comes to axle weights.

After the machine is loaded, it must tighten so it stands securely on the trailer. Depending on
the size of the machine, there may be required markings on the truck if it is wider or longer
than the law allows. In some cases, an escort car to warn other road users should accompany
the transport.

1.20.1 Do not become part of a statistic!

If you are not careful, you expose many innocent people to danger. As operator, you are always
responsible. Do not become another accident statistic!

052 General Safety Rules

When you have finished studying this chapter, try to answer these questions.

1 What types of machines are available in UAE?

If you are unsure of the
answer, go back and re-read
the relevant section in the
chapter. Please note that the
questions do not cover all of
the content of the chapter.

2 What type of work 3 Why are there 4 What can you do to

can you use the safety rules? reduce the vibration of
machines for? your machine?

5 Who has the greatest 6 Where can you easily 7 Provide examples
responsibility at find information of personal
the workplace? about the machine? protective equipment.

8 What type of fire 9 How do you step in and 10 What is best practice to
extinguishers must be out of the machine? avoid hearing damage?
in the machine?

General Safety Rules 053

11 Which is most important 2 What is the safety
12 13 Explain the safe
to check before you start distance at the way to refuel?
digging into the ground? side of power lines
with low voltage?

14 What is the safety 15 What is the safety 16 What is the safety

distance at the side of distance in height distance in height to
power lines with high to the power lines the power lines with
voltage above 40 kV? with low voltage? high voltage?

17 Should you use rotating 18 What must be done when 19 What is the
beckon when you work you know you are digging economical driving and
on a public road or in an area where there how it achieved?
public areas? can be electricity, gas
lines or water lines?

20 How can we reduce global warming?

054 General Safety Rules

Chapter Two
VEHICLE
KNOWLEDGE
2.1 Understanding of Internal Combustion piston engines
Inside the engine there is a piston that moves up and down and it is connected to a crankshaft.
The crankshaft reciprocates the movement of piston into a rotating movement.

Piston Engine parts:

2.1.1 Cylinder block 2.1.3 Oil sump 2.1.5 Crankshaft

The main part of the Piston with a piston rod. Is fitted just above the oil sump
engine is made of cast Oil sump is fitted under the and transfers the up and down
steel or aluminum. cylinder block and holds the movements of the pistons to a
lubricating oil for the engine. revolving movement.

2.1.2 Cylinder head 2.1.4 Pistons 2.1.6 Camshaft

Pistons are moving up and Camshaft is driven by the

down in the cylinders. The crankshaft through a belt or
pistons have piston rings to chain and lifts the valves.
minimize leaks between the
cylinder and the piston.

The top part covering the top

of the cylinders. To withstand 2.1.7 Air intake and exhaust manifolds
the high pressure To avoid
leakage of coolant or engine It is fitted to the cylinder
oil in cylinder head in the block normally opposite each
cylinders, a gasket is fitted other. The air intake sends air
between the cylinder block to the engine and the exhaust
and the cylinder head. manifold sends the exhaust
gases from the engine to
When fitting the cylinder head the exhaust pipe. Internal
the bolts must be tightened Combustion piston engines
with a torque wrench to the can be either two-stroke
prescribed torque. engine or four-stroke engine.

058 Vehicle Knowledge

2.2 Two stroke engine
It has two working cycles:

• Combined intake
stroke and
exhaust stroke

• Power stroke

In the two-stroke engine the

piston opens and closes
holes, one for the fuel
mixture and one for the
exhaust gases.

1. Piston is moving
up, compressing
the fuel-air
mixture. At the
1 2
same time, the
fuel-air mixture
is drawn in under
the piston.

2. A spark plug
ignites the fuel-
air mixture and
the piston is
pressed down.

3. Exhaust gases
start leaving the
engine at the
same time as the
fuel mixture is
pushed in. 3 4
4. The fuel-air
mixture is
pressed up and
pushes out all the
exhaust gases.

Vehicle Knowledge 059

2.3 Four stroke engine
Almost all new petrol and diesel engines are four stroke engines. The inlet and exhaust opens
and closes with valves that are operated by a camshaft, valve lifters and rocker arms.

In this engine, the working cycle has four strokes:

• Intake stroke • Exhaust stroke makes the

The piston starts at Once the piston hits explosion
the top, the intake the bottom of its more powerful.
valve opens, and stroke, the exhaust
the piston moves valve opens • Power stroke
down to let the and the exhaust When the piston
engine take in a gases leaves the reaches the top of
mixture of air and cylinder to go out its stroke, the fuel
fuel. This is the the tailpipe. mixture is ignited.
intake stroke. Only The fuel charge
the tiniest drop of • Compression stroke in the cylinder
fuel needs to be Then the piston explodes driving the
mixed into the air moves back up piston down.
for this to work. to compress this
fuel/air mixture.
Compression

Intake Compression Power Exhaust

060 Vehicle Knowledge

2.4 Diesel engine
The diesel internal combustion cylinders using computers monoxide, and unburned
engine differs from the petrol- to deliver precisely the hydrocarbons. Emissions of
powered engine by using a right amount of fuel the re- active nitrogen compounds
higher compression of the instant it is needed. All (commonly known as NOx)
fuel to ignite the fuel, rather functions in a modern diesel and particulate matter
than using a spark plug (i.e. engine are controlled by an (PM) have been reduced
“compression ignition" rather electronic control module by over 90 percent since
than "spark ignition"). that communicates with an 1980. Nevertheless, NOx
elaborate array of sensors and PM emissions remain
In the diesel engine, air placed at strategic locations at relatively high levels.
is compressed with a throughout the engine to NOx contributes to acid rain
compression ratio typically monitor everything from and smog, while adverse
between (15 and 20) %. engine speed, to coolant and health effects have been
This compression raises the oil temperatures, and even associated with exposures to
temperature to the ignition piston position. Tight electronic high PM amounts.
temperature of the air by control means that fuel burns
compressing. The fuel is then more thoroughly, delivering All machine diesel engines
injected in the power stroke. more power, greater fuel have several cylinders. If the
Self-ignition takes place when economy, and fewer emissions cylinders are in a line, the
the fuel is combined with the than yesterday’s diesel engines engine will be longer than if
hot air. Therefore, the diesel could ever achieve. the cylinders are arranged
engine has no spark plugs. as a V. Many machines have
Modern direct-injection diesel 4, 6, or 8 cylinders.
Today’s diesels inject fuel engines produce low amounts
directly into an engine’s of carbon dioxide, carbon

Intake Compression Power Exhaust

Vehicle Knowledge 061

2.4 Diesel engine
2.4.1 Diesel engine pros and cons

• Works at low engine • Gives high torque. high compression

revolutions. and greater heat
• Does not need an produced.
• Has high ignition system.
compression • Generates
pressure in the • Needs to be made more noise.
cylinders. much stronger
because of the • Uses less fuel.

2.4.2 Cold start device

When a diesel engine is cold, the compression process may Instead of glow plugs,
not raise the air to a high enough temperature to some light machines have
ignite the fuel. Therefore, some diesel engines are fitted a pre-heater that heats
with glow plugs. up the incoming air to the
engine when starting in
The glow plug has an electrically heated wire that heats the cold weather.
combustion chambers and raises the air temperature when the
engine is cold so that the engine can start.

Pre-heater Glow plug

Some light machines have a pre-heater that

heats up the incoming air to the engine when
starting in cold weather.

062 Vehicle Knowledge

2.5 Air induction
Inlet manifolds collect the clean air for the cylinders.

2.5.1 Air filter 2.5.2 Paper filter

The engine uses a lot of air. Pleated paper filters are the
most common engine air
To stop dust from entering the engine, all the air must go cleaners, because they are
through an air filter. It is good practice to change the filter often. efficient, easy to service, and
cost- effective. As long as a
pleated-paper filter is sized
appropriately for the airflow
volumes for a particular
engine, such filters present
very little restriction to air
flow until the filter becomes
clogged with dirt.

2.5.3 Oil bath filter

It consists of a round base

bowl containing a pool of oil,
and a round insert, which is
filled with fiber, mesh, foam,
or other coarse filter media.
The air goes through the oil.
Heavier dust and dirt particles
will fall into the oil and settle at
the bottom of the base bowl.
Lighter and smaller particles
are trapped by the filtration
media, which is wetted by
oil droplets by the normal
airflow. Oil bath cleaners are
used in off road and machine
equipment where very high
levels of dust are encountered,
as oil bath air cleaners can
take a great deal of dirt relative
to their overall size.

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2.6 Turbo charger
Many diesel engines are
equipped with a turbo to
give them more power. The
turbo is driven by exhaust
gases and pumps in extra
air to the engine.

With more air to the

engine, more fuel can be
added and the engine will
give more power.

The turbo runs with very

high revolutions, often
75,000 to 130,000. There-
fore the turbo must always
have sufficient oil to the
bearings. The oil to the
turbo is pumped by the
engine’s lubrication system.

If the machine has been

driven hard (the turbo
is running fast),do not
switch off the engine
immediately when you
stop the machine.

Wait 1-2 minutes and let

the turbo slow down before
switching off the engine
to avoid running the turbo
without proper lubrication.

Some new machines are

equipped with an
electric turbo.

The exhaust gases turn

the turbo, and electricity
is generated by the
combined electric motor/
generator. When extra
power is needed, the turbo
can speed up the electric
motor and provide more air
to the engine.

064 Vehicle Knowledge

2.7 Exhaust system
The following items can be found in the exhaust system:

2.7.1 Silencer 2.7.4 Exhaust pressure regulator (EPR)

The exhaust pipe is equipped A warm engine produces much less harmful exhaust gases
with a silencer that reduces than a cold one. Therefore, it is good if the engine reaches
the noise from the engine. working temperature as fast as possible.

The EPR is a valve, that if closed, will increase the back

pressure in the exhaust system, and the engine will heat
2.7.2 Catalytic up to working temperature faster. This will reduce bad
converter exhaust gases.

The catalytic converter is

described in "Environment
and Exhaust Gases”.

2.7.3 Particle filter

A diesel particle filter,

sometimes called a DPF,
removes particles or soot
from the exhaust gas of a
diesel engine. Diesel particle
filters usually remove about
85% of the soot. A diesel
machine equipped with a
functioning filter will emit
no visible smoke from its
exhaust pipe.

In addition to collecting the

particles, there must be a
method to clean the filter.
Some filters are single use
(disposable), while others
are designed to burn off
the accumulated particles,
either with a catalyst, or
through an active technology,
such as a fuel burner, which
heats the filter to soot
combustion temperatures,

The exhaust pipe is equipped

through engine modifications
or through other methods.

with a silencer.
This is known as "filter
regeneration".

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2.8 Smoking engine
A diesel engine should not smoke. If your machine is smoking, there is something wrong with
the engine. A smoking machine produces exhaust gases that are harmful to humans and to
the environment.

An engine in proper condition should not smoke.

2.8.1 Black smoke

Black smoke is the most common smoke emitted from diesel engines. It indicates poor and
incomplete combustion of the diesel fuel. There are many causes, including:

• Incorrect timing rings or worn

components)
• Dirty or worn
injectors • Dirty air cleaner

• Faulty turbocharger • Restricted air

(i.e. not enough air inlet (e.g. air filter
to match the fuel) blocked or kinked
inlet piping)
• Incorrect
valve clearance • Poor quality fuel

• Incorrect air/ • Cool engine

fuel ratio operating
temperature
• Low cylinder
compression (e.g.
sticking piston
Smoking engine

2.8.2 Blue smoke

is an indication of oil being burnt. The oil can enter the combustion chamber for several reasons:

• Worn valve • Cylinder glaze. past the rings)

guides or seals
• Piston rings sticking • Fuel dilution in the
• Worn in power oil (oil thinned out
assemblies (i.e. • Incorrect grade of with diesel)
cylinders, piston oil (e.g. oil is too
rings, ring grooves) thin, and migrating

066 Vehicle Knowledge

2.8.3 White smoke 2.8.4 Environment and exhaust gases

Occurs when raw diesel The exhaust gases from is highly toxic to humans
comes through the exhaust machines are not good for and animals. Hydrocarbon
completely unburned. Some you and for the environment. in exhaust gases is burned
causes of this include: It is important that the engine or partially burned fuel.
be in good condition to avoid Hydrocarbons are poisonous
unnecessary pollution. and are a major contributor
• Faulty to smog - a major problem
or damaged Today, many machines have a in urban areas. Prolonged
injectors catalytic converter connected exposure to hydrocarbons
to the exhaust system. The contributes to asthma, liver
• Incorrect catalytic converter for diesel disease, and cancer.
injection timing engines reduces the amount
(could be worn of carbon monoxide (CO) Nitrogen oxides are 300
timing gear) and hydrocarbon (HC) but times more potent than
not nitrogen oxides (NOx) carbon dioxide as a
• Low cylinder and particles (soot). Catalytic greenhouse gas. NO2
compression converters for petrol engines makes up approximately 7.2
(e.g. caused reduce CO, NOx and HC. percent of the gases that
by leaking cause global warming.
or broken Carbon monoxide is a
valves, piston colorless, odorless, and Petrol vehicles with catalytic
ring sticking, tasteless gas that is converters substantially
cylinder and/ slightly lighter than air. It reduce the amount of NO2.
or ring wear, or
cylinder glaze. Scania 13.0-liter, Euro 6-compliant diesel engine with
catalytic converter.

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2.9 The fuel system
2.9.1 The fuel tank 2.9.2 Fuel filters

stores fuel for the engine. Baffles inside the tank ensure that remove abrasive
the fuel always reaches the tank even if the vehicle is leaning particles and water.
to one side and stops air from entering the system.

2.9.3 The Fuel pump

sends the fuel from the tank

to the high-pressure diesel
pump. The fuel pump can be
a diaphragm-type lift pump
mounted on the engine, or a
separate electric pump. The
diaphragm-type pump has an
eccentric on a camshaft that
pushes on a rocker arm. It
acts on a diaphragm that will
move up and down to create
a pressure difference, which
lifts fuel from the tank to the
injection system.

A pump is mounted on the

in-line injection pump, and
driven by a cam inside the in-
line injection pump housing.
This pump provides very high
pressure to the injectors.

068 Vehicle Knowledge

2.9.4 The injector

Is not designed to withstand To keep the diesel engine at the desired speed, a mechanical
even the smallest dirt. Any or pneumatic governor adjusts the amount of fuel sent to the
dirt or particles will cease it cylinders. The accelerator pedal controls the governor.
from working properly.

Some machine’s diesel

engines use a priming pump
to remove air from the fuel
system. Otherwise, if air has
entered the fuel system, the
engine would have to be
cranked over with the starter
motor, to bleed and prime the
system, or the fuel system has
to be bled manually.

To get the right amount

of fuel to the cylinder, a Basic Fuel Injection System
distributor-type pump uses
a transfer pump to fill the
Fuel
single pumping element. Injector
This then raises fuel pressure Intake Open Exhaust
to injection pressure. A Valve Fuel Valve
distribution system then
distributes fuel to each
cylinder, in the firing order of
the engine. As fuel pressure
rises, it acts on the needle
valve in the injector, eventually
lifting it from its seat. Fuel
under high pressure enters
the engine in an atomized Diesel
Engine
spray at high speed.
«Power»
Stroke
Superfluous diesel from the
injectors is sent back to
Fuel Supply Lines
the fuel tank. 1 per cylinder

The injector pump and the Excess Fuel Return Line

injectors are designed with
very small tolerances. Any Fuel level
dirt in the diesel can destroy sensor
the components. Therefore, High-Pressure
Fuel
Diesel Fuel Injection
a diesel fuel system has Filter
Pump
fuel filters that must be
changed regularly.

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2.9 The fuel system
2.9.5 Electronic fuel system

Many new machines have a up to 2000 to even 3 000 Electronic Diesel Control
more modern fuel system bar (determined by the (EDC) precisely controls all
called Common Rail injection pressure setting the injection parameters
Fuel Injection. in the engine control unit), – such as the pressure
independently of the engine in the rail and the timing
In the common rail injection speed and the quantity of and duration of injection
system, the generation of fuel injected. The fuel is – as well as other engine
the injection pressure is fed through rigid pipes to functions. The common
separate from the injection the injectors, which inject rail fuel injection system
itself. A high-pressure pump the correct amount of fuel reduces fuel consumption
generates in an accumulator in a fine spray into the and emits cleaner
– the rail – a pressure of combustion chambers. The exhaust gases.

Pressure Sensor Pressure Limiter

Common Rail

Filter

Supply Pump
EDU
Injectors ECU

Fuel Tank
EDU- Electronic Driver Unit
ECU - Electronic Control Unit

070 Vehicle Knowledge

2.9.6 Bleeding the fuel system

If the diesel engine stops

because the machine
runs out of fuel, it will not
be enough to just fill up
the tank again. The fuel
system must be bled before
it can start.

On many machines, a
bleeding valve has to be
opened and fuel must be
pumped by hand until all the
air is gone and clear fuel is
coming out of the
bleeder valve.

Some machines have a

self-bleeding system that
will bleed itself by simply
cranking the engine with the
starter motor. The bleeding
can take up to 1 - 2 minutes
before the engine starts.

As each machine is bled

differently, always check
the operator’s manual
for how to do it on
your machine.

Bleeding pump mounted

on top of the fuel filter. The
pump is on top, and the
circled valve to the left is
the bleeding valve. Open
the valve while pumping so

If the diesel engine stops

air will leave the valve.

because the machine

Bleeding pump mounted
on top of the fuel filter. The

runs out of fuel, it will not

pump is on top, and the
circled valve to the left is

be enough to just fill up

the bleeding valve. Open the
valve while pumping so air

the tank again.

will leave the valve.

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2.10 Machine’s lubrication system
All moving parts in the engine
and transmission must be
constantly lubricated.

The engine has an oil sump

filled with oil, and an oil pump
that transports the oil to
different parts of the engine.
The steering box, gear- box
and the differential on the
driving axles are also filled
with oil. Grease is also applied Relief
valve
on many places.
Lines
It is essential that the right and
jets
type of oil is used and
that oil levels are checked
Pressure
regularly. The machine regulator
manual outlines oil guidelines valve
Filter
and the necessary oil filter
change intervals.
Oil sump
It is always good practice to
change the oil and oil filter Oil pump
Strainer
often. Never overfill the engine
oil. Always keep the oil level
within the maximum and
minimum markings. If there is
too much oil in the engine, the Oil cooler
oil seals can start leaking.

Some machines have

an oil cooler fitted. It
works like a radiator, but
instead of cooling water, it
cools engine oil.

Cooling the oil will make for

a better lubricant.

Never overfill the engine oil. Always keep

the oil level within the maximum and
minimum markings.

072 Vehicle Knowledge

2.10.1 Mineral oil or synthetic oil

There are a number of different types of engine oils on the market. Mineral oil has been the
standard oil, however today you can buy synthetic oils or a mixture of both. The machine manual
will outline which type of oil the manufacturer recommends.

Remember that when you top up always use the Synthetic oil is often the better choice of oil,
even though it is more expensive.

Advantages of synthetic oil:

• Better low and

high temperature
viscosity
performance

• Better chemical &

shear stability

• Decreased
evaporative loss

• Resistance
to oxidation,
thermal
breakdown
and oil
sludge problems

• Extended drain
intervals –
producing less
oil waste, thereby
benefitting the
environmental

• Improved fuel
economy in
certain engine
configurations
Synthetic oil Mineral oil
• Better lubrication
on cold starts

• Longer engine life Overall, synthetic oil provides the best protection under
extreme temperatures and against hot spots, for less
oil burn off.

Vehicle Knowledge 073

2.11 Cooling system
The composition of the fuel used in the engine, less than half of its energy is transferred to the
moving of the machine. The rest creates heat in the engine. As the engine should not work at a
high temperature, there must be a cooling system ensuring it remains at a steady temperature.

2.11.1 Air-cooling 2.11.3 Radiator

Air-cooled engines are In the radiator, the cooling liquid is cooled by wind passing through
common on motorcycles, the radiator.
lawn movers and other small
engines. They are cheaper Never block the air from freely entering and going through
than water-cooled engines. the radiator.

2.11.2 Liquid- cooling When the machine is moving, air is forced through the radiator;
when the machine is stationary or moving slowly, a fan behind
Water-cooled engines are the radiator draws air through it. Nowadays a thermostat controls
the cooling system on the cooling fan.
almost every car, bus, truck
and machine today. 2.11.4 Cooling liquid

The engine is cooled by The cooling liquid will not freeze to ice in cold weather and
liquid circulating through will minimize rust in the engine. Therefore, the liquid is not just
the engine and cooling off in pure water, but water mixed with other liquid. Most common is
the radiator. A water pump either ethylene glycol (ENG) or propylene glycol (PGW). Refer
pumps the cooling liquid to the machine manual to know what is recommended for
and a thermostat adjusts your machine.
the flow to keep the engine
temperature at a fixed level.

The engine runs best and

uses least fuel if it is not too
cold or too hot (about 80-90
C is normally the best engine
temperature).

The cooling system works

under pressure to stop the
engine from boiling at high
temperatures.

It is fitted with an expansion

container that takes up the
change of liquid volume when
the engine is hot or cold.

Air-cooled engines are

Never open the radiator cap
when the engine is hot

common on motorcycles.
and never fill cold water in
a hot engine.

074 Vehicle Knowledge

2.12 Electrical system
The electrical system in a machine supplies electricity to the starter motor and to the lights.

Nowadays a machine has electronic equipment, computerized systems, sensors and electrically
controlled maneuver systems.

A machine uses a lot of electricity; if the electrical system is malfunctioning, it can be impossible
to operate the machine. The electrical system on machines is complicated. Computerized
systems have made it difficult to fully understand what to do if something is wrong.

2.12.1 Batteries 2.12.2 Generator

The generator produces

electricity for the machine. It
is driven by a belt connected
to the engine in the same way
the radiator fan belt is driven.
The generator produces
alternative current and must
have a rectifier to provide
the direct current needed for
the batteries.

The battery stores electrical As the generator produces alternative current it is often called
energy. The generator an alternator. Modern alternators have a voltage regulator built
charges it. Avoid draining into them a type of alternator for machines.
the battery. A battery will
last long if only 10-20 % of 2.12.3 Relays
its capacity is used and if it
often fully charged. A relay is an electric switch.
With a small amount of
A battery that is stored electricity, the relay can switch
should be charged at on and off high currents. You
least every month. will find many different relays
in the machine. They control
Light machines normally all electrical
use two batteries in series
that provide 24Volts. The 2.12.4 Fuses
batteries can be sealed
or open. The sealed type Fuses protect the electrical system from breaking down. If
is maintenance free but there is a short cut somewhere in the electrical system, a fuse
the open type should be will blow, thereby protecting the system from major damage.
topped up with distilled
water when needed. You will find several different
fuse boxes on a machine.
The Sulfuric acid in batteries Refer to the manual to see
is harmful - you should where they are and what the
avoid its contact with your different fuses are for. Always
skin or clothes. replace a fuse with one with
the same Ampere rating.

Vehicle Knowledge 075

2.13 Engine 2.14 Engine oil 2.16 Coolant
Emergency pressure temperature
Lamps warning lamp warning lamp

A problem has occurred Inspect the engine oil level. This lamp flashes, and an
in the engine lubrication If the lamp is flashing even alarm is sounded, if the
system or the coolant though the level is normal or engine coolant temperature
water temperature has if it continues flashing after rises abnormally while
irregularly risen. oil is added, consult your the engine is running.
sales or service outlet. Inspect for the cause as
soon as possible, and stop
• When there working until the problem is
is a problem completely rectified.
in the engine
lubrication 2.15 Battery charge 2.17 Air cleaner
system, the warning lamp warning lamp
engine oil
pressure
warning
lamp flashes.

• When the
coolant water
temperature
has risen
over the
normal limit,
the coolant
temperature There is a problem with the This lamp lights when the air
warning fan belt or charger. Inspect cleaner element is blocked.
lamp flashes. the fan belt for slack or
breakage and adjust as The lamp flashes and an
needed. If the lamp continues alarm sounds if the air
If this central warning is flashing after maintenance, cleaner filter is clogged
flashing, check the other there is a problem with the while the engine is running.
warning lamps to see where charger. Consult your sales or Check the filter and clean
the problem is. service outlet. or replace it.

076 Vehicle Knowledge

2.18 Machines
hydraulic
Machines and tools use 2.18.1 Open center circuits
hydraulic fluid to work.
Hydraulic fluid is transmitted use pumps, which supply a and from an actuator and tank.
throughout the machine continuous flow. The flow is The fluid's pressure will rise to
to various hydraulic returned to the tank through meet any resistance, since the
motors and hydraulic the control valve's open center; pump has a constant output.
cylinders, which become that is, when the control valve If the pressure rises too
pressurized according to the is centered, it provides an open high, fluid returns to the tank
resistance present. return path to the tank and through a pressure relief valve.
the fluid is not pumped to a Multiple control valves may
The fluid is controlled high pressure. be stacked in series. This type
automatically by control of circuit can use inexpensive,
valves and distributed Otherwise, if the control valve constant displacement pumps.
through hoses and tubes. is actuated it routes fluid to
The popularity of hydraulic
machinery is due to the large
amounts of power that can
be transferred through small Hydraulic Cylinder
tubes and flexible hoses; and
the high power density and
array of actuators that make
use of this power.

Hydraulic machinery is Retract/Extend

operated by the use of
hydraulics, where a liquid is Reservoir
the powering medium. For the
hydraulic fluid to work, it must
flow to the actuator/motor then
return to a reservoir. The fluid
is then filtered and re-pumped.
Control valve
The path taken by hydraulic
fluid is called a hydraulic circuit
of which there are several
types. Open center circuits and
Closed center circuits Filter pump

Hydraulic
2.18.2 Closed center circuits
machinery
is operated
supply full pressure to the control valves, whether any valves
are actuated or not. The pumps vary their flow rate, pumping

by the use
very little hydraulic fluid until the operator actuates a valve.
The valve's spool therefore doesn't need an open center return

of hydraulics,
path to the tank. Multiple valves can be connected in a parallel
arrangement. The system pressure is equal for all valves.

Vehicle Knowledge 077

2.18 Machines hydraulic
2.18.3 Hydraulic fluid 2.18.4 Filters

Hydraulic fluid, also known Filters are an important part of hydraulic systems. Metal
as tractor fluid, is the life particles are continually produced by mechanical components
of the hydraulic circuit. It is and need to be removed along with other contaminants.
usually petroleum oil with
various additives. Some Filters may be positioned in many locations. The filter may be
hydraulic machines require located between the reservoir and the pump intake. Blockage
fire resistant fluids, depending of the filter will cause cavitation and possibly pump failure.
on their applications. In Sometimes the filter is located between the pump and the control
some factories where food valves. This arrangement is more expensive, since the filter,
is prepared, either an edible housing is pressurized, but this eliminates cavitation problems
oil or water, is used as a and protects the control valve from pump failures.
working fluid for health and
safety reasons. The third common filter location is just before the return line
enters the reservoir. This location is relatively insensitive to
In addition to transferring blockage and does not require a pressurized housing, but
energy, hydraulic fluid needs contaminants that enter the reservoir from external sources are
to lubricate components, not filtered until passing through the system at least once
suspend contaminants
and metal filings for
transport to the filter, and
function well under several
hundred degrees C.

Hydraulic fluid,
also known as
tractor fluid,
is the life of
the hydraulic
circuit. It
is usually
petroleum
oil with
various
additives.

078 Vehicle Knowledge

2.18.5 Tubes, pipes and hoses

2.18.5.1 Hydraulic tubes 2.18.5.2 Hydraulic rubber hose

Are seamless steel It is graded by pressure, The weakest part of the

precision pipes, specially temperature, and fluid high-pressure hose is the
manufactured for compatibility. connection of the hose
hydraulics. The tubes to the fitting.
have standard sizes for Hoses are used when pipes
different pressure ranges, or tubes cannot be used, Another disadvantage of
with standard diameters usually to provide flexibility hoses is the shorter life
up to 100 mm. for machine operation of rubber, which requires
or maintenance. periodic replacement, usually
The tubes are supplied by at five to seven year intervals.
manufacturers in lengths of The hose is built with
6 m, and are cleaned, oiled rubber and steel layers. Tubes and pipes for hydraulic
and plugged. Different types Multiple layers of woven applications are internally
of flanges interconnect wire and rubber surround a oiled before the system is
the tubes(Especially for rubber interior. The exterior commissioned. Usually steel
larger sizes and pressures), is designed for abrasion piping is painted outside.
welding cones/nipples (with resistance. The bend radius Where flare and other
O-Rings seal), several types of the hydraulic hose is couplings are used, the paint
of flare connection, and by carefully designed into the is removed under the nut, and
cut-rings. In larger sizes, machine, since hose failures is a location where corrosion
Hydraulic pipes are used. can be deadly; violating the can begin. For this reason,
Direct joining of tubes by hose's minimum bend radius in marine applications,
welding is not acceptable will cause failure. Hydraulic most piping is made of
since the interior cannot hoses generally have steel stainless steel.
be inspected. fittings swagged on the ends.

Vehicle Knowledge 079

2.18 Machines hydraulic
2.18.6 Reservoir

The hydraulic fluid reservoir separation of air from the Reservoirs can also help
holds excess hydraulic fluid fluid and works as a heat separate dirt and other
to accommodate volume accumulator to cover losses particulate from the oil,
changes from cylinder in the system when peak as the particulate will
extension and contraction, power is used. Design generally settle to the
temperature driven engineers are always bottom of the tank.
expansion and pressured to reduce the size
contraction, and leaks. of hydraulic reservoirs, while Some designs include
equipment operators always dynamic flow channels on
The reservoir is also appreciate larger reservoirs. the fluids return path that
designed to aid in the allow for a smaller reservoir.

080 Vehicle Knowledge

2.18.7 Hydraulic pump

Seal

Suction port

Drive gear

Drive shaft
Case seal

Mounting flange

Pressure port

Bushings

Idler gear

Hydraulic pumps supply fluid to the components in the system. Pressure in the system develops
in reaction to the load. Hence, a pump rated for 5,000 psi is capable of maintaining flow against a
load of 5,000 psi. Pumps have a power density about ten times greater than an electric motor (by
volume). An electric motor or an engine, connected through gears, belts, or a flexible elastomeric
coupling to reduce vibration, powers them.

Types of hydraulic pumps:

2.18.7.1 Gear pump 2.18.7.2 Vane pump 2.18.7.3 Radial piston pumps

Cheap, simple, and durable Cheap, simple, and reliable. A pump that is normally
(especially in g-rotor form). Good for higher-flow and low- used for very high pressure
Less efficient because pressure output. at small flows.
they are constant (fixed)
displacement. Mainly suitable
for pressures below 20 0

MPa (3000 psi).

4
3

90 270

180

Vehicle Knowledge 081

2.19 Regular Maintenance
Regular maintenance of all the systems of your machine will ensure maximum machine efficiency and
long life. Follow the rules below to make sure you are doing your best to maintain the machine:

• Check the fluid • Never interfere with or fuel is leaking.

level of the factory set hydraulic Oil and fuel are
equipment’s system as you could explosive and their
hydraulic system cause failure of the presence could
before starting equipment, which present a hazard.
each day’s may result in injury.
operation. If
necessary, add • Never attempt
hydraulic oil as • Always maintain the to lubricate,
recommended Safety Signs in good adjust, or remove
in your readable condition. material from the
operator’s manual. attachment while
the machine is in
• Make certain that motion or while the
• After every the “Slow Moving engine is running.
eight hours Vehicle” (SMV) sign
of operation, is installed in such a
lubricate all way as to be clearly • Do not fill up the
grease fittings as visible and legible. fuel tank while the
recommended. engine is running.
If fuel is spilled,
• Do not modify or move the machine
• After every ten alter any component away from the area
hours of operation, of the machine. Do of the spill and
check all hardware not permit anyone avoid creating any
and tighten to modify or alter source of ignition
where required. the machine. until the fuel has
evaporated.

• Replace hoses • Never work under

immediately if they the attachment, • Avoid contact
are damaged by unless the with hot surfaces
cut or scrape. attachment is including hydraulic
securely supported oil tanks, pumps,
or blocked up to motors, valves and
• Hydraulic oil leaks prevent sudden or hose connections,
should be repaired unintended falling. engine surface or
promptly to avoid muffler. Relieve
loss of oil and hydraulic pressure
serious personal • Do not operate the before performing
injury from Equipment machine maintenance
escaping oil. if with hydraulic oil or repairs.

082 Vehicle Knowledge

2.20 Troubleshooting

Fault / malfunction Possible cause Remedy

The engine radiator

/ oil cooler air flow is Clean it
restricted by debris

Coolant level is too low Fill it up

The engine is The thermostat is jammed

Have the thermostat
getting too hot replaced at the garage

V-belt loosened from

Tighten the V-belt
the fan blade

Oil level is too

Adjust the oil level
low or too high

Hydraulic oil cooler is dirty Clean it

V-belt loosened from

Tighten the V-belt
The hydraulic the fan blade
system is
getting too hot Hydraulic fluid level is too low

Reduce the machine

Load too high
load, take breaks

Replace it

Machine Wrong fuel grade Change the fuel

performance
is too low Inching is stuck Check/repair

Engine speed is too low Adjust it

Vehicle Knowledge 083

2.21 Operating’s Physics
As a machine operator, you are handling large and complicated machines. The construction of
machines is much more complicated than anything you may have handled before. Machines are
large and the forces acting upon them can easily take over if you are not careful. Therefore, it is
very important that you understand the operating physics of a machine.

Definitions
The following is a list of common measurements associated with machines:

Electrical voltage is 1 kilo Pascal (kPa)= 1000 Pa.

measured in Volts (V). 100 kPa = 1 bar = 1.02 kg/cm2.
Small machines normally The torque for how hard a bolt should be tightened is measured in
have 12 V batteries. Light Nm (Newton meter).
machines use two batteries 1 kpm =9.81 Nm.
in series, and therefore have
a 24 V electrical system. An Engine cylinder volume is the total volume given in the engine’s
electric plug in an average cylinders, between the pistons upper and lower turning points.
house has 220-240 V. It is measured in liters (l) or cubic centimeters (cc).
1 liter = 1000cc
Electric current is the
flow of electric charge Engine torque is measured in Nm, and does the engine give the
going through a wire. It is moment of force. It is good to know at what revolution the engine
measured in Amperes (A). gives the highest torque.
If the wire is thick, more
current can pass through it. Engine revolutions are measured in revolutions per minute (RPM).

Electric power is the amount

of power consumed and is
measured in Watts(W). If you
multiply Voltage with Current,
you get power (V x A = W).

Battery capacity is measured

in AH (Ampere x Hours). If a
battery has 100 AH, then you
can theoretically use 10 A
continuously for 10 hours.

Engine power is measured

in kW (kilo Watts = 1000
watts). A previous method
of measuring engine power
was in hp (horsepower).
One hp is equal to 0.736 kW.
If a machine has a 100 kW
engine, it has 135 hp.

Air pressure is measured in

Pascal (Pa).

084 Vehicle Knowledge

When you have finished studying this chapter, try to answer these questions.

1 What ignites the fuel mixture in a diesel engine?

If you are unsure of the
answer, go back and re-read
the relevant section in the
chapter. Please note that the
questions do not cover all of
the content of the chapter.

2 What happens if 3 What should you 4 Can you clean

you drive the diesel use when topping up an air filter?
tank on empty? the radiator?

5 Why do some 6 Can you clean a 7 What types of hydraulic

diesel engines hydraulic filter? pumps are there?
release black smoke?

8 Why do you have fuses 9 Briefly describe 10 What could be the cause
in the electrical system? why it is important of blue smoke from the
that the warning exhaust pipe?
lights are working?

Vehicle Knowledge 085

11 What is the advantage of 2 What is the
12 13 What Engine Operating
a Diesel Engine? disadvantage of a Temperature can be
Diesel Engine? regarded as normal?

14 What is the unit of 15 What is the unit of 16 What is the unit of

Electrical Voltage? Electrical Current? Electric Motor Power?

17 How many 18 What is the purpose of a 19 What is the purpose

Horsepower (HP) is Generator (alternator)? of the Battery?
equivalent to 100 kW?

20 Which battery Voltage is the most common in Light Machinery?

086 Vehicle Knowledge

Chapter Three
LIGHT BULLDOZER
(SKID STEER DOZER)
3.1 Introduction to Bulldozers
A bulldozer is a piece of light mechanical equipment used widely on construction sites. It can
cut, fill and transfer materials such as:

• Stone • Gravel • Sand and other

lose or packed
• Rocks • Asphalt materials.

• Soil • Demolition
wreckage

Manufacturers, construction companies, and operators sometimes have different names

for this machine. It is sometimes also called a track-laying tractor, a skip loader dozer, or just
simply, a dozer.

3.2 The Structure of the Bulldozer

Exhaust
Pipe Stack Air pre-cleaner Operator cabin
filter

Ripper Cylinder
Blade Lift Cylinder

RIPPER

Ripper
BLADE
shank

Cutting
edge Track CRAWLER Final drive Ripper
TRACTOR tip tooth

090 LIGHT BULLDOZER (SKID STEER DOZER)

3.3 The Operator’s Environment

4
2

1. Steering Control 5. Electronic, • Advisor Monitoring

Programmable System (AMS)
2. Operator’s Seat Dozer Control
7. Wide
3. Adjustable Armrests 6. Monitoring Panoramic View
Display System
4. Electronic 8. Heating and Air
Ripper Control • In-Dash Instrument Conditioning
Cluster

LIGHT BULLDOZER (SKID STEER DOZER) 091

3.3 The Operator’s Environment
3.3.1 Dozer Control Levers

A low-effort electronic bulldozer control handles gives the operator control of all
dozer functions.

Commonly bulldozers are Push the left joystick to 1:30 right joystick to raise the rear
equipped with three control and you will move forward implement linkage. Pull back
joysticks one on the left and and right at a 45-degree on the joystick to lower the
two on the right. angle. 7:30 will track the rear implement linkage.
dozer back and left at a
Push forward on the left 45-degree angle. Simply, When equipped with the
joystick and the Bulldozer whatever direction you push optional dual tilt feature, the
will move forward. or pull the left joystick, the thumb lever at the top of the
dozer will track. When you handle controls blade pitch.
Pull back, the Bulldozer release the joystick, the Forward and backwards.
tracks backwards. dozer will stop. The trigger switch toggles
between single and dual tilt.
Pull right or left on the left Pull back on the right, front The left and right side thumb
joystick to turn right and left, joystick to lift the blade. buttons provide control over
respectively. In addition to Push forward on the joystick the Semi-automated blade
the four basic directions, you to lower the blade. Pull left pitch functions that the dual
can turn at angles. Imagine on the joystick to tilt the tilt attachment provides.
the face of a clock below blade left. Push right on the
the left joystick, 12 o'clock is joystick to tilt the blade right. Blade pitch for load, carry
forward, 6 o'clock is reverse. Push forward on the back,

092 LIGHT BULLDOZER (SKID STEER DOZER)

and spread segments can be preset on the Advisor Monitoring System (AMS) and controlled by
the buttons. The left-side button cycles between the pitch settings for each segment of the push
cycle. The right-side button cancels out of the pitch functions without losing the preset pitch
angles. This Auto Blade Assist (ABA) feature is turned on and off using a switch on the right-side
console. The two buttons also provide control over the AccuGrade™ blade control attachment
when the machine is so equipped.

The buttons turn on AccuGrade, provide auto increment and decrement control, and turn
off AccuGrade.

AccuGrade™ blade control

LIGHT BULLDOZER (SKID STEER DOZER) 093

3.4 Bulldozer Attachments

Not all bulldozers have heavier weight. The ripper

the same functionalities points tend to be about 10 to • Hinge ripper
and capabilities. Different 15 cm wide. Heavier dozers
manufacturers offer a provide more pressure due • Parallelogram
variety of attachments for to their weight, which means ripper
the basic bulldozer, helping more penetration. “Ripping
users adapt the machine to rock” is a bit of an art form. • 2 Barrel ripper
the particular application.
On the rear of the machine Un fractured formations • 4 Barrel ripper
you will find very commonly of rock sometimes do not
either a ripper or a winch, rip, regardless of the size • Single
although in the logging of the dozer applied, but un shank ripper
industry sometimes grapples fractured formations are
are provided. rare, and the challenge is to • Multi-
know your rock well enough shank ripper
The larger dozers (200 to predict whether and how
HP and up) usually have it will rip.
rippers because these
machines tend to be used in Quarry engineers will have
quarrying and strip mining access to a seismograph
applications. The ripper is to measure the density of
useful for loosening up the the rock, but the traditional
ground so that the blade will approach is to stick the
be able to penetrate and fill it ripper to the rock and see
quickly. The rippers are able what happens. If the rock
to penetrate where a blade does not respond to the
will simply scrape along. ripper, a bigger bulldozer or
explosives may be required.
Larger, heavier dozers will rip
rock that lighter machines There are several designs of
won't touch. This capability rippers, each designed for a
is mostly a function of their different application:

094 LIGHT BULLDOZER (SKID STEER DOZER)

3.5 Bulldozer Operators 3.6 Training
Bulldozer operator jobs Only trained and qualified workers should operate a bulldozer.
involve much more than They must follow all workplace safety requirements as well as
knowledge about how to those in the equipment’s operating manual. Bulldozer operators
operate heavy equipment. need to understand and follow all warning labels and signs
First, you should be posted on the machine.
physically fit and determined
to maintaining your good 3.7 Performing Maintenance
health. The job is physically
demanding: bulldozer Periodic safety inspections and scheduled maintenance of all
operators must be able to bulldozer systems should be performed by qualified personnel
climb up onto equipment in accordance with operating manual standards.
and withstand heavy
vibration and repetitive Safe maintenance practices include performance of all
motion for hours at a time.
3.8 Before Work
Before applying to a
bulldozer operator job, you Bulldozer operators need to perform a pre-start inspection. They
should learn about how should also check around the machine to ensure that the area is
different kinds of bulldozers free of obstacles and that all personnel are prepared. Operators
operate, even if you have must make sure that the horn and automatic back-up alarm
not had a chance to operate are functional. Visibility is critical; windows must be clean and
them. Caterpillar, Komatsu, unobstructed.
John Deere (bulldozer
manufacturers) and others 3.8.1 Pre-Use 3.8.2 Pre-shift
have all slightly different Procedures inspection
controls and features.
Maximize the safety of
With their enormous size, your operation by making • Always perform a pre-
bulldozers can cause it second-nature and shift inspection, which
serious human injuries and instinctive to perform some includes checking
even death, if not operated of the following procedures at fluid levels, brakes,
properly. The following various stages. steering, lights and
points list some of the signals, tires, hydraulic
most important safety Remember that thoroughly cylinders/lines, horns,
measures for the operation reviewing and understanding operating controls,
of bulldozers: the information provided seat belts and safety
in the bulldozer operator’s devices.
manual, particular attention
given to descriptions of • If a dozer fails the
safety procedures, is the best pre-shift inspection,

Always
training to prevent injury. notify your supervisor
and remove the

perform a
Refresher training is required bulldozer from service
annually and an evaluation of by attaching a red tag

pre-shift
each operator’s performance stating, “DO NOT USE.”
must be conducted at least Note the reason, date

inspection.
once every three years. and your name on the
tag.

LIGHT BULLDOZER (SKID STEER DOZER) 095

3.9 Operating Precautions

• Before operating Structures • Never use

a bulldozer, check (ROPS). a bulldozer
the work area for to demolish
obstructions and • Operators must structures
hazards including always use that are taller
ditches, slopes, seat belts when than the
hills, excavations, operating a bulldozer itself,
streams, and bulldozer. unless there
underground and is sufficient
aboveground • Operators must overhead
utility lines. mount and protection.
dismount using
• Employees only the steps • Mechanics
working within and handholds must follow
the bulldozer provided on the proper lockout,
work area must bulldozer. blackout,
wear flagging and tag out
garments (i.e., • Bulldozer blades procedures
orange vests) and attachments when a bulldozer
and at least a must be kept is in repair.
hard hat, steel- close to the
toed boots, and ground while • When parking,
long pants. the machine shift into neutral
is moving. and set the
• Never carry parking brake
passengers on a • Bulldozers to immobilize
bulldozer. should be the machine.
parked on level Lower the blade
• Stunt driving is ground whenever and any other
prohibited. possible. attachment to
the ground then
• Do not operate • The bulldozer shut off engine.
a dozer with must be
a leaking fuel equipped with • Operators
system or leaking an automatic must use
brake system. back-up alarm. proper towing
procedures
• Bulldozers must • Shut off engine and equipment
be equipped whenever for bulldozer
with Rollover refueling. attachments.
Protection

Never use a bulldozer to demolish structures

that are taller than the bulldozer itself.

096 LIGHT BULLDOZER (SKID STEER DOZER)

3.10 Example Procedural Check-list
3.10.1 Start-up and shut down of the machine

Starting the machine After starting the engine Moving the machine

• Perform walk- • Allow machine • Make sure

around inspection. to warm-up for area is clear.
5 minutes at
• Mount the LOW IDLE. • Raise all
machine using lowered
three points • Engage and implements.
of contact. disengage
attachment • Depress
• Turn the battery controls to help brake pedal.
disconnect speed warm-
switch to ON. up of hydraulic • Release
components. parking brake.
• Engage the
parking brake. • Cycle all controls • Move
to allow warm transmission
• Adjust seat, fasten oil to circulate control
seat belt. through all to desired
cylinders direction.
• Make sure all and lines.
implements are • Release brake
grounded. • Check gauges pedal and check
and action lights for proper
• Move transmission frequently. operation.
control lever
into neutral.

• Move the Machine shut down

attachment control
levers into HOLD.
• Park machine on • Turn key start switch to
• Make sure all smooth, level area. OFF and remove key.
personnel are clear
of machine. • Set the • Turn battery disconnect
parking brake. switch to OFF
• Set the throttle
control to • Lower all hydraulic • Dismount machine
LOW IDLE. implements. using 3-point contact.

• Turn the key start • Move the throttle • Conduct post-operation

switch to START. control to LOW walk around inspection.
Crank engine. IDLE and run
5 minutes.

LIGHT BULLDOZER (SKID STEER DOZER) 097

3.11 Know Your Working Area
It is important to keep in mind that knowing your terrain is almost as crucial as knowing
your machine. Some factors regarding your environment to consider before moving your
bulldozer are:

• Location them before you • Never approach

of slopes. begin working. power lines with
any part of your
• Conditions of • When working machine unless
haul roads. on roads, make all local or state
sure you have required safety
• Direction of travel considered the precautions have
on haul roads. pedestrians been taken. Use
and other extreme caution.
• Holes, mud vehicles around
or other the machine. • When operating
obstructions. the machine
• When working in inside a
• Flow of traffic. water or muddy building, know
grounds, check your machine
• Thick dust, the depth of the dimensions and
smoke or fog. water, the solidity what clearances
of the ground, you will
• Exact location and the speed encounter, such
of any buried of the current as overheads,
or overhead beforehand. Make doorways, aisles,
electrical, gas, sure the ground is and the weight
telephone, water, strong enough to limitations of the
sewer, or other bear the machine floor and ramps.
utility lines. weight and that Make sure there
If necessary, the water is not is sufficient
have the utility deeper than the ventilation for
company to permissible inside operation.
mark, shut off, depth.
or relocate

098 LIGHT BULLDOZER (SKID STEER DOZER)

3.12 How to Operate a Bulldozer in different situations?
In this section, we will review the basic operations that you will face while operating a bulldozer.
We will also review some common situations you will face and what best practices are with
regards to safely navigating these situations.

3.12.1 Pushing with a Bulldozer Blade

Bulldozer blade attachments

can be fitted to many types
of outdoor equipment, such
as tractors and skid steers.

Whether it is a conventional
bulldozer or an accessory
blade fitted to a tractor, the
principles by which bulldozer
blades are operated and used
to move earth are identical.
The only major differences
arise from the platforms to
which they are attached.
While a fully tracked machine
like a bulldozer or Skid Steer
Dozer has great traction
and can turn in place, a
tractor or other wheeled
platform cannot. Tracked dozer

This difference should

always be kept in the
operator's mind: Wheeled
vehicles require more room
to maneuver and cannot
safely be used on slopes as
steep as a tracked machine.

Lower the blade until it is

biting into the soil slightly,
and start the machine
forward, pushing the earth
ahead of you. Always remove
earth in relatively thin
layers (thinner for wheeled
machines than for tracked
machines, which have more
traction), and be careful not
to let earth collect ahead
of the blade until it spills
over the top. Wheeled dozer

LIGHT BULLDOZER (SKID STEER DOZER) 099

3.12 How to Operate a Bulldozer in different situations?
When you reach the end of a
run, reverse the machine to
the beginning of the area you
are trying to clear and then
remove another layer. Tilting
the blade left or right will let
you conform it to the terrain
or help you build the earth
into the shape you desire.

Adjust the angle at which

the dozer assembly is
mounted to the machine, if
you need to angle the blade
more than then you can
achieve with the Moving forward with blade onto the ground
pistons alone.

This allows you to remount

the blade to the machine at
an angle which, when added
to the angle created by the
motion of the cylinders,
allows the blade to reach the
desired angle.

Tips & Warnings

Always return the blade

control lever to hold position
when the cylinders approach
the end of their stroke.
Reversing machine with the tools lifted
This allows the hydraulic
fluid to bypass the valve that
controls the cylinders, and
greatly reduces wear.

Wheeled
vehicles
require more
room to
maneuver. Cylinder approach the end of the stroke

100 LIGHT BULLDOZER (SKID STEER DOZER)

3.12.2 Operating Bulldozers in Wet Areas.

Bulldozers are useful for earth-moving operations in demanding environments.

Because they operate on tracks rather than wheels, they distribute their weight more evenly
over the drive surfaces and are less susceptible to becoming stuck in mud and loose fill.
While tracked machines are well-suited to operating in muddy environments, a common
misconception is that they can never get stuck. In fact, bulldozers can get stuck and are very
hard to get out once they are.

Observing a few common-sense safety rules can help keep you safe while operating tracked
heavy equipment in wet conditions:

• Examine hazards can your bulldozer

government- be hidden by to the size of
issued maps of high brush. Pay the job. Small
your work site special attention bulldozers are
to determine around any cheaper to
whether there old buildings rent, and they
may be any that may are easier to
hidden structures still be there. retrieve if they
left from past become stuck.
facilities. Be • Identify any
especially wet areas on • Call a
careful of septic the site. Pay professional
tanks, drainage special attention excavation
ditches and to low and company if you
cisterns (House uneven ground. feel uneasy
hold water about the job.
storage tanks) • Push a stake You can still
. Your bulldozer into the ground oversee the work
could fall into in the wet areas without risking
these water-filled using your hand. injury to yourself
hazards and If you are able to or expensive
become stuck. push it in easily equipment.
for several feet,
• Walk the site you should avoid
before beginning using a bulldozer
to operate your in that area.
bulldozer. Holes,
bogs and other • Match the size

Bulldozers are useful for earth-moving

operations in demanding environments.

LIGHT BULLDOZER (SKID STEER DOZER) 101

3.12 How to Operate a Bulldozer in different situations?
3.12.3 How to Bulldoze Wet Sand or Mud

Efficient bulldozing is a
complicated job that can
take years to learn. It takes
a lot of skill to use a large
machine to flatten an area
without cutting it too deep
or too shallow anywhere.
Despite the difficulty in
operating the machinery
with such precision, some
core concepts are very
simple, as follows: Machine stuck in wet area

• Aim straight at the where the wet sand • Move slowly and
dump whenever or mud is being methodically to
possible. This removed, then break avoid slippage and
prevents the the ground while stalls. Traction
bulldozer from moving downhill and means the bulldozer
turning while push the loose wet is operating at
carrying material, sand or mud back its most efficient
and minimizes up the hill. level. Sudden
the amount of wet movements can
sand or mud it will • Dig slots with about cause the bulldozer
lose when the turn one third of a blade to lose traction and
is made. It also width between them. stop or jerk into
prevents wear on the This maximizes the the wet sand or
steering components amount of material mud, causing loss
from rotating the the bulldozer can of material and a
bulldozer under a carry by preventing rutted surface.
heavy load. wet sand or mud
from slipping around • Keep the blade
• Bulldoze downhill the sides of the full as much as
whenever possible blade. Once the possible. A full
so the weight of slots are finished, blade is easier to
the bulldozer helps the center can be manage than a
move the wet sand removed quite easily. partially full one. If
or mud. If you push Don't use slots if you find the blade
uphill, then the you're bulldozing on is not full when
bulldozer has to the flat because the it should be then
move its own weight push may be too long reverse and add
and that of the wet and the bulldozer more material
sand or mud. If could become stuck. on the pass.
the dump is above

102 LIGHT BULLDOZER (SKID STEER DOZER)

3.12.4 Operating Bulldozers in Steep Terrain.

Operating dozers in steep and mud slides increasing land clearing, and site
terrain requires special the danger of slippage and inspections and surveys.
attention and terrain-specific tipping of the equipment as
technique because several well as a destruction of any In all of these situations,
dangers are presented by work already completed by the specific slope must
moving light machinery the machinery. be assessed for current
over an incline. Improper environmental conditions
dozer operation on inclines Many projects require and risks, and those results
causes extra unnecessary operation of dozers on need to be taken into
erosion and waste of both steep inclines, including consideration for maximum
top and subsurface soil, and road building and safety and effectiveness of
it can also cause rock, land construction site excavation, dozer operation.

Operate the bulldozer up and down straight rather than across sloped terrain.

LIGHT BULLDOZER (SKID STEER DOZER) 103

3.12 How to Operate a Bulldozer in different situations?
Instructions:

• Choose the right tires should roll Should the dozer

time to operate over them. begin slipping
the dozer on downhill, turn
steep terrain • Wear the dozer's the nose of the
by assessing seat belt at all dozer directly
the weather, times during downhill and
presence of operation on lower the basket
standing water steep slopes. or blade to the
and the visibility Do not operate ground. Keep
across the site. a dozer on a the basket or
Wait to begin slope where blade in its
dozer operations other dozers are lowest traveling
if any of these working on the position while
factors are less same slope at moving over
than optimal. lower elevations sloping terrain.
Consider also to eliminate
the length of the risk of the • Operate the
time needed dozer rolling dozer on steep
for the dozer to or slipping into slopes in its
finish its task the path of lowest gear
and whether other workers. to provide
environmental maximum
conditions are • Station a control over
likely to worsen supervisor or the machine.
before the co-worker at a
dozer finishes safe distance
and leaves the from where the
sloped site. dozer is working
on the slope

Operate
• Stabilize the and instruct him
slope by first or her to watch

the bulldozer
waiting until any dozer operations
standing water through

up and down
evaporates and completion
mud hardens. and to provide

straight
Compact any assistance
loose gravel in case of

rather than
and remove emergency.
boulders that

across
raise from the • Drive slopes
slope surface straight up and

sloped
enough to tip down rather
the dozer on its than at an angle

terrain.
side if individual or sideways.

104 LIGHT BULLDOZER (SKID STEER DOZER)

3.12.5 Operating Bulldozers in Mountain areas

As residential and commercial expansion claims more and more land, the development of
steeply sloped and graded land in the mountains is becoming more and more prevalent.
Landscaping and excavation in the mountains are inherently riskier than on level ground.
Awareness, training and a conservative approach are key aspects of any successful
mountainside landscaping operation.

Instructions Bulldozer working in Mountain area

• Measure the
grade of the slope
before beginning
any project on
steep or sloped
terrain. Bulldozers
are not made to
be operated on
any slope greater
than 45 degrees.
For utmost safety,
slopes of 20 to 25
degrees are best.
• Buckle the safety out onto the
• Read the belt and harness slope. Check
operator's manual and tighten for loose rocks,
thoroughly if you according to the unstable soil
are unfamiliar instructions in the (indicated by
with the machine. operator's erosion), and
Particularly manual. other possible
read sections traction concerns.
pertaining to • Operate the
operation on bulldozer up and • Abandon
steep slopes. down rather than the machine
Every machine across sloped immediately if
has different terrain. This slippage causes
controls and it applies for even the dozer to slide
pays to be aware mild rises. It is into a steeply
of them before more efficient for graded area of the
you get into a fuel consumption, slope. Attempting
situation where and safer. to drive the
you need to locate dozer out of
a particular brake • Walk the terrain such a spot can
or decelerator you are going result in serious
pedal quickly. to grade before harm to you and
driving the dozer the machine.

LIGHT BULLDOZER (SKID STEER DOZER) 105

3.13 Parking
Dozers should be parked on level ground whenever possible.

If they must be parked on a grade, the tracks should be blocked to prevent roll-away. Always
put the shift into neutral and set the parking brake to completely immobilize the machine.
Lower the blade and any other attachments to the ground. This will also help prevent the
bulldozer from moving.

Always place the blade in the ground when parking the machine.

106 LIGHT BULLDOZER (SKID STEER DOZER)

When you have finished studying this chapter, try to answer these questions.

1 What is the main use of a Bulldozer?

If you are unsure of the
answer, go back and re-read
the relevant section in the
chapter. Please note that the
questions do not cover all of
the content of the chapter.

2 What is the use 3 How should you 4 What is important to

of a "RIPPER"? run in a hillside on keep in mind before you
the safest way? begin working with the
crawler-type Machine?

5 Is it allowed to stand 6 Name one major 7 How should the

on the track when you advantage of position of the blade
start the Machine? the Bulldozer’s be held when you
maneuvering capability? reverse the Machine?

8 How will you primarily 9 At what angle of 10 What type of surface

do if the Machine inclination of the slopes, should you avoid
cannot manage to push should you avoid driving a Bulldozer
the material forward? driving a Bulldozer? on if possible?

LIGHT BULLDOZER (SKID STEER DOZER) 107

11 How often should you 2 Why you should not
12 13 After a rain, what should
lubricate your Machine? jump off the track? you primarily consider?

14 When is the greatest 15 What can happen if 16 Which protective

risk for lateral sliding of you turn abruptly with equipment (PPE) is the
the Bulldozer? the Bulldozer? most important when you
are driving a Bulldozer?

17 Which system is the most 18 What is the most 19 When you finish the
common in a modern important measure day’s work what it is
Bulldozer today? to take after you most important to you?
have adjusted the
track-tension?

20 What should you primarily do if you have detected an oil leakage on a hydraulic cylinder?

108 LIGHT BULLDOZER (SKID STEER DOZER)

Chapter Four
LIGHT WHEEL LOADER
(SKID STEER LOADER)
4.1 INTRODUCTION LIGHT WHEEL LOADER

Skid steer loader, also known Long arms with forks pivot from behind the operator to lift
as a skid-steer or skid-loader, and move objects in front of the vehicle.
is a piece of light equipment
often used in the initial Skid loaders steer by "skidding," much like a tank, and the
phases of a construction machine turns by moving the left wheels/tracks at a different
project. This machine direction and speed than the right wheels/tracks.
differs from a front loader
or a bulldozer in that the lift Skid loaders can turn quickly at their center, making them
arms are beside the driver much more agile than a tank or typical track vehicle.
instead of in front.

They fit into small spaces, Brands Function

can turn within a tight
radius, and are easy to The most common Skid loaders can remove
operate and therefore, brand of skid steer debris faster than even
operators or workers can loader is a Bobcat. 10 workers moving debris
enjoy much work success manually, can also be used
with the skid steer loader. In fact, the term "Bobcat" for Leveling, Pushing, Loading
is often used generically or Transferring of material
Skid steers have four wheels when referring to a skid like: soil gravel, demolition
or two tracks with the steer loader, much the wreckage. It can be used to
two on the left operating same way as Kleenex is remove and deposit soil in
independently of the two used when referring to gardens and to clear land on
on the right. facial tissue. construction sites.

112 LIGHT WHEEL LOADER (SKID STEER LOADER)

4.2 SKID STEER STRUCTURE

1 4

5
2

1. Life Arm 4. Roll Over Protection 6. Bucket

System (ROPS) Attachement
2. Hydraulic
5. Safe Entry Aids
3. All-Wheel Steer Grab Rail and
Non-Slip Step

LIGHT WHEEL LOADER (SKID STEER LOADER) 113

4.3 THE OPERATOR´S ENVIRONMENT
In many ways, the tractor of a skid steer loader is like any other vehicle. It has a Monitor Panel
that displays important details such as the amount of remaining fuel, the temperature of the
engine-cooling water and the temperature of the engine oil.

4.3.1 Operator´s Controls

Most of the skid steer loaders are controlled by Hand joysticks and Foot pedals

4.3.1.1 Joystick Controls

• Forward
Travel - Move
both joysticks
forward.
FORWARD
• Backward
Travel - Move
both joysticks
backward. BACKWARD

• Forward Left Turn

- Move the right
joystick farther
forward than the
left joystick. LEFT TURN

• Forward Right
Turn - Move
the left joystick
farther forward RIGHT TURN
than the right
joystick.

• Left Fast Turn

- Move the left
joystick backward LEFT FAST TURN
and the right
joystick forward.

• Right Fast
Turn - Move
the left joystick RIGHT FAST TURN
forward and the
right joystick
backward.

114 LIGHT WHEEL LOADER (SKID STEER LOADER)

4.3.1.2 Control pedals

Left pedal

The left pedal raises or

lowers the lift arm (boom).

Use the left heel to push on

the back of the pedal to raise
the lift arms up.

Use the left toes to push

on the front of the pedal to
lower the bucket.

Right pedal

The right pedal controls the

load bucket.

Use the right heel to push on

the back of the pedal to roll
the bucket back.

Use the right toes to push

on the front of the pedal to
dump the bucket.

LIGHT WHEEL LOADER (SKID STEER LOADER) 115

4.4 Difference Between a Wheel Loader & a
Skid Loader

Heavy construction of the operator, with the loaders, which makes them
equipment has evolved engine behind the machine. suitable for smaller job sites
over the years to include Normally built on wheels, or compact working areas.
function- specific wheel loaders can be used
machine types to help the for basic functions such as In a wheel loader, the
construction industry work dirt and snow removal. arms that lift the bucket
more efficiently. Both wheel are positioned in front
loaders and skid loaders are Skid loaders are a little of the operator, due to
common on construction more sophisticated: they its larger size.
sites, with the primary are fashioned the same
difference between the way, with the bucket and This is also why it’s called
two being the placement engine in the same areas, a “front-end” loader. In
of the arms responsible for but skid loaders can have contrast, the skid loader
lifting the bucket. wheels or tracks. has the lift arms situated
right behind the operator's
A wheel loader consists Additionally, skid loaders are shoulders, since it is a
of a bucket placed in front much smaller than wheel smaller machine.

116 LIGHT WHEEL LOADER (SKID STEER LOADER)

4.5 Skid Steer Attachments

It is tempting to assume that all loaders are the same. That is not the case. Most manufacturers
offer a variety of attachments for use with the basic loader to help the operator adapt the
machine to a particular task. Some attachments are pictured below. There are a lot of
accessories which are adapted to different types of jobs

4 in 1 bucket Angle Blade

Paler fork grapple Excavator

Hammer Fork

Trencher Auger

Remember!!
Lifting attachments can change the weight distribution of the loader. Attachments can also
affect the loader’s stability and handling response

LIGHT WHEEL LOADER (SKID STEER LOADER) 117

4.5 Skid Steer Attachments
4.5.1 Fitting an Attachment

Though you should always check the manufacturer’s manual and safety guide for any
attachment before fitting it to your loader, the general guidelines are as follows.

1. Place the This procedure 11. Apply grease to

attachment or often needs each pin to the
bucket in the the help of a manufacturer’s
normal mounting small pry bar or specifications.
position. guide pin

12. If the attachment

2. Clean all pins 7. To align the has hydraulic
and bushes boom and boss, connections,
thoroughly. guide the crowd these should now
cylinder to be connected.
its boss.
3. Apply grease to Store the bungs
all pivot points This operation and caps for
according to the is much simpler later use.
manufacturer’s with two people.
specifications.
13. Start the shovel.
8. Insert the crowd
4. Start the loader cylinder pin.
and idle up to the 14. Operate the
attachment. Make sure attachment,
the shims are checking for any
in place. binding or undue
5. Align the boom movement.
with their
respective 9. Shut down
bosses in the the shovel. 15. Check for
attachment. hydraulic leaks
as appropriate.
10. Fit the snap ring,
6. Insert the boom clip or bolt to
pins. Make sure each of the pins.
the washers are
in place.

You should always check the manufacturer’s

manual and safety guide for any attachment.

118 LIGHT WHEEL LOADER (SKID STEER LOADER)

4.5.2 Quick couplers

Automatic Quick hitch in the

closed position. Additional
safety is available by way of
a large pin manually inserted
through the hole on the
bottom left preventing any
movement by the hitch.

Quick couplers (also called

quick hitches) are used with
construction machines to
allow the rapid change of
buckets and attachments on
the machine. They obviate
the need for hammers to
manually drive out and
insert the mounting pins for
attachments.

Note the large spring on the

ram, this helps to prevent
accidental release of
the attachment.

However, though more

convenient and faster, quick
hitches also bring additional
safety risks that must be
overcome by careful design
and manufacturing, and
proper use by you.

Detailed Description

Quick couplers are devices on the backhoe equipment of backhoe loaders, but are also
installed at the outer edges installed on telescopic handlers, wheel loaders, skid-steer
of various types of loaders and the loader equipment of backhoe-loaders. They
construction and earth- are also occasionally installed on attachments installed on
moving machines. agricultural tractors.

They facilitate the rapid Quick couplers do not normally have a specific function
exchange of working tools themselves, as they do not carry out handling or digging
or buckets. Quick couplers operations, but when installed on a machine they become a
are most common on part of the overall system. They are usually mounted on the
hydraulic excavators and machine by means of the pins that would otherwise be the
compact excavators and mountings for the bucket or attachment.

LIGHT WHEEL LOADER (SKID STEER LOADER) 119

4.5 Skid Steer Attachments
4.5.3 Types of Couplers

There are many variations in the design of quick couplers. The two main types are “dedicated”
couplers, which are made for specific attachments, and “pin grabbers,” which can pick up a range of
buckets and attachments by clamping onto the mounting pins of the attachment.

The claimed advantage of pin-grabbers is their flexibility: you can use a variety of buckets and
attachments without changing the quick coupler or buying an adaptor. The advantages of dedicated
couplers depend on their individual design, but often include better performance and smaller size.

4.5.4 Operation of Couplers

The method of operation (the picking up and releasing of buckets and attachments) causes the next
divergence in design. The types can be described as manual, semi-automatic, and automatic.

Manual Automatic

This operation is done with Automatic couplers use a failure of the hydraulic
the help of tools at the the hydraulic system of the system. Within the above
coupler itself. machine to operate the main three categories, there are
attachment mechanism, with many further differences
The operator needs to an internal safety device. in operating principles and
leave the operator's station detail of design. There are
(usually the cab) to manually As with semi-automatic competing claims relating to
release the bucket or systems, the safety device the safety and performance
attachment, and then again is designed to prevent the benefits and demerits of
to attach the next bucket or release of the bucket or each type of design.
attachment to be used. attachment in the event of

Semi-automatic

With semi-automatic The safety device is The safety device is most

couplers, the hydraulic intended to prevent the commonly a pin that must
system of the machine is release of the bucket be inserted to prevent one of
used to operate the main or attachment in the the components in the quick
attachment mechanism. event of the failure of coupler moving to release
However, some manual work the hydraulic system, or the bucket or attachment.
is still necessary, for the other major failure of the Some designs require the
operation of a safety device attachment mechanism. manual operation of a lever
located at the coupler. on the quick coupler.

There are competing claims relating to

the safety and performance benefits and
demerits of each type of design.

120 LIGHT WHEEL LOADER (SKID STEER LOADER)

4.5.5 Safety issues with couplers

Though couplers can the known fatalities were suppliers of these couplers
make operations more caused by the operator not agreed to this voluntarily so
convenient, fatalities have inserting the safety pin in semi-automatic couplers
occurred due to buckets semi-automatic couplers. were withdrawn from sale
being accidentally released Even without the safety pin, in the UK by around October
from work equipment during the buckets would not have 2008. Safety authorities in
operation. Released buckets been released unless there other countries have taken a
have hit bystanders causing had been a failure of some different approach.
fatal injuries. part of the mechanism, or
some error in operation by In Australia the authorities
The causes of the fatal the operator. took the view that the
accidents are not always problems were caused
the same and the views In the UK, it was concluded by designs of quick
of safety authorities in that the most effective way couplers that did not
different countries differ on to reduce the risk of further incorporate a safety pin.
how to reduce risk. In the accidents was for semi- That is, they believe that
UK, analysis of the accident automatic couplers to be semi-automatics are
data concluded that all of withdrawn from sale. The fundamentally safe.

LIGHT WHEEL LOADER (SKID STEER LOADER) 121

4.6 Operating a Skid Steer Machine
The compact size and versatility of skid steer loaders make them a common tool on
construction sites, landscaping jobs and farms. Learning how to operate them will enable you to
apply for many jobs in the construction field. However, operating a skid steer loader involves a
combination of physical and cognitive skills and abilities.

First, you should have a Before applying to skid steer loader operator jobs, you should
complete physical exam learn how different kinds of skid steer loaders operate.
to determine if you are in Depending on the manufacturer, different skid steer loaders
good health. Skid steer will have slightly different controls and features.
loaders operators must be
able to climb up onto the In this section, we will review the most common functions
machine and withstand of a skid steer loader with instructions on how to perform
heavy vibration and repetitive these operations.
motion for hours on end.

4.6.1 Entering and Exiting the Machine

Enter the skid steer loader only when the bucket or other attachment is resting on the ground,
or when the lift-arm supports are in place. Don't use foot or hand controls to aid in entering or
exiting the loader. Never exit the loader unless the blade/bucket has been lowered to the ground,
the parking brake set and the engine turned off.

122 LIGHT WHEEL LOADER (SKID STEER LOADER)

Climbing In

Because of its small size and design, an operator must enter a skid steer from the front of the
vehicle. This method presents challenges that can lead to injury if the driver fails to follow the
proper safety precautions. You can climb into a skid steer safely with the proper equipment after
learning a few simple steps, as follows:

• Read the operator's or attachment is different attachment

manual before raised, you must use is mounted on the
operating any the lift arm supports, control arms of the
skid steer. which extend skid steer, place your
vertically from a flat foot in the indented
• Wear a hard hat, base on the ground step provided just
safety goggles, work to each control below the driver's
gloves and steel- arm to prevent compartment.
toe safety shoes the unintentional
before entering lowering of the arms • Maintain a three-point
and operating the during use. contact at all times as
skid steer. you raise yourself up
• Face the front of the and into the driver's
• Check the immediate skid steer, and use compartment. Do
area around the skid- both hands to grasp not use the skid steer
steer. Alert others in the entry handles lateral-steering levers
the vehicle operating located on each or hydraulic control
area that you are side of the driver's levers as handles.
preparing to use compartment.
the vehicle. • Fasten the safety
• Place one foot belt once seated in
• Check the front- on the tread plate the vehicle.
loader bucket or any located on the top
other attachment to of the bucket if your • Never exit a skid
ensure it is on the skid steer has a steer without shutting
ground. If the bucket bucket attached. If a down the engine.

Operation

Never overload the machine,

as uneven distribution of
weight may cause
it to tip over.

Be aware of your surroundings

and keep all parts of your
body inside the cab while the
loader is running.

LIGHT WHEEL LOADER (SKID STEER LOADER) 123

4.7 Weight distribution 4.8 Before you start
the Operations
Engineers design skid steer loaders with unequal loading
between the front and rear axles. • Perform a pre-
start inspection.
Balance is another important ingredient that must be added to
the design recipe for stability and turning capability. • Check around
the machine
to ensure the
area is free of
30% 70%
obstacles and
that all personnel
are clear.

• Operators must
make sure
the horn and
automatic back-
up alarm are
functional.

• Visibility
is critical;
NO LOAD IN THE BUCKET windows must
be clean and
70% 30% unobstructed.

LOADED BUCKET

Balance is another important

Maintenance

ingredient that must be

Keep the foot pedals on the
skid steer loader clear of

added to the design recipe for

all types of debris, such as
dirt and oil. Don't modify the

stability and turning capability.

operator's cabin or remove
the exterior screens.

124 LIGHT WHEEL LOADER (SKID STEER LOADER)

4.9 How to Use a Skid Steer?
Skid steers operate through skid braking, that is, they use their tracks (or wheels) to move and
turn the machine. These days, skid steers are used more often than front-end loaders because
of their speed and size. The skid steer is used mostly on farming and construction sites because
the machine can fit into places that a front-end loader or a fork-lift cannot.

Once you are in the operator’s seat, follow the steps below to get moving:

• Read over the including the right

operator's manual and left hand levers front part of the left
and familiarize and the right and foot pedal with the
yourself with all of left foot pedals. front of your shoe to
the safety factors lower the skid steer
that are involved • Move the throttle bucket. The front
in operating a lever up to part of the left foot
skid steer. increase the speed pedal is the closest
of the engine. Grab to the front of the
• Familiarize yourself both hand levers skid steer.
with all of the levers with your hands
and controls before and move the hand • Press down on the
operating the levers forward back of the right
machine to prevent at the same time foot pedal with the
any accidents. to move the skid heel of your shoe
steer forward. to make the bucket
• Check all of the pivot upward. Press
fluids inside of the • Pull back on both down on the front of
skid steer, including hand levers at the right foot pedal
the oil and the the same time with the front of your
coolant level. to reverse the shoe to pivot the
skid steer. bucket downward.
• In the operator's The front of the
seat, pull the safety • Push the left hand right foot pedal is
bar over your lap. lever forward while positioned near the
Lock the safety pulling the right front of the skid
bar down. The hand lever back to steer while the back
safety bar has to turn the machine of the right foot
be locked in place to the right. pedal is positioned
over your shoulders toward the driver.
before the engine • Push the right hand
will crank. lever forward while • Use the hand levers
pulling the left and the foot pedals
• Turn the ignition hand lever back to in conjunction
key until the engine turn the machine with each other to
cranks. Familiarize to the left. operate the skid
yourself with all steer in a safe and
of the controls, • Press down on the efficient manner.

LIGHT WHEEL LOADER (SKID STEER LOADER) 125

4.9 How to Use a Skid Steer?
4.9.1 Basic Operations

Select your speed

• Sit in the operator's chair.
operator's seat Make sure that all
of the skid steer. of these switches • To the lower right
Fasten the safety are turned away of the operator's
belt and lower from the padlock seat is a lever
the locking roll symbol embossed with "Fast" or
bar into position. on the frame. "Slow" marked
Verify that the If your model on it. Alternately,
safety glass or skid steer uses it may have a
mesh surrounding an ignition key, turtle and rabbit
the operator's insert the key and symbol; the turtle
cage is intact turn it to the first equals "Slow" and
and attached to position; wait for the rabbit, “Fast.”
the skid steer the glow plug Use a slow speed
frame. If anything light (next to the setting until you
is damaged or ignition) to turn are accustomed
missing, exit the off before turning to your skid steer.
skid steer and do the key all the way
not use it. to the right to start
the skid steer.
Some models use Practice raising and
• To start the skid a fuse and switch lowering the bucket until
steer. On some system. The fuse it is a fluid and natural
models, there is at the center movement for you.
may be a switch of the top of the
or a series of front frame inside This is the one motion of
switches over the cab. Insert the skid steer that is most
the center front the fuse and turn likely to affect your balance.
frame or to the the switch. The more natural it feels to
lower right of the you, the better you will be
able to sense any imbalance
under load and take
corrective action.

Do not operate any skid

steer without protective
design elements such as a
roll bar, seat belt or
operator's cage.

A skid steer that has been

modified or whose protective
design elements are damaged
is unsafe to operate; serious
injury can occur if you use it.

126 LIGHT WHEEL LOADER (SKID STEER LOADER)

4.9.2 Techniques for filling, lifting, carrying and emptying load

As a wheel loader operator, you will spend most of your working time either filling, lifting, carrying
and emptying loads of material. Below are instructions for the various functions,

4.9.2.1 Filling the Bucket

• Approach and
enter the pile with a
level bucket.

• Lift and roll back

the bucket to
increase the
efficiency. The
bucket will naturally
throughout the
lifting cycle
resist the lift
and increase the
breakaway effort.

• Learn to scoop
and dump with the
bucket using the
right pedal.

• Driving the bucket

to the first pile.

• If you want to move

a pile of dirt, raise
the bucket until
it is about 2.5 to
5 cm above the
ground, then drive
the machine to the
pile of dirt.

• Prepare to load
the bucket. Stop
the machine just
before you reach
the dirt pile, and
lower the bucket to
the ground.

LIGHT WHEEL LOADER (SKID STEER LOADER) 127

4.9 How to Use a Skid Steer?
4.9.2.2 Loading the bucket

By driving the machine

forward and pushing the
bucket into the dirt pile while
also lifting the bucket up.

When the bucket is full,

back away from the dirt
pile while lowering the
bucket until it is 20 cm
above the ground.

Never drive with a loaded

bucket higher on the
machine than your knee;
the weight in the bucket can
change the balance of the
machine and cause it to tip
if it is higher.

4.9.2.3 Dumping the load.

Drive the machine over to

where you will be placing the
dirt, begin to raise the bucket
as you move forward, dump
the bucket and then reverse
the machine. Raise the
bucket again, then lower it
back to the driving position.

Do not be concerned if the

bucket is not completely
filled during each pass.
Maximum productivity is
determined by the amount
of material loaded in a given
period. Time is lost if two or
more attempts are made to
fill the bucket on each pass.

Time is lost if two or more attempts are made

to fill the bucket on each pass.

128 LIGHT WHEEL LOADER (SKID STEER LOADER)

4.9.2.4 Lifting the load

When lifting the load, keep the bucket positioned to avoid spillage.

4.9.2.5 Carrying the Load

• Always position
the bucket close
to the ground
for maximum
stability and
visibility,
whether it is
loaded or empty.

• Use extreme
care when
operating the
loader on a
slope, keep
bucket as low as
possible. This
keeps center
of gravity low
and will provide
maximum
stability.

LIGHT WHEEL LOADER (SKID STEER LOADER) 129

4.10 Leveling and Pushing Operations

• Leveling should while gradually • Shovel some

always be done spreading soil from more soil into the
with a machine the bucket. bucket, put the
in reverse. lift arm in float,
• Level out the soil level the bucket at
• Shovel up soil into over the ground ground level and
the bucket. with the bucket smooth the
teeth touching the ground by
• Move the machine ground by back- moving
backwards dragging the soil. backward.

Leveling should always be done with a

machine in reverse.

130 LIGHT WHEEL LOADER (SKID STEER LOADER)

4.11 Loading a Truck
When loading trucks from a bank or a stockpile with a single loader, use the V-loading method.

This method is comprised of the following steps:

• Head the loader • Approach the haul • Dump the bucket by

toward the bank unit at a 90° angle, rolling the bucket
or stockpile in lifting the bucket slowly forward. Do
slow speed and fill high enough to not let the bucket
the bucket. clear the haul unit. hit the haul unit.

• Hold the bucket • Proceed slowly • Back away from

in the upright forward until the the haul unit while
and curled bucket is over the simultaneously
position, and back haul unit. Do not lowering the
away from the touch the haul unit boom and leveling
stockpile or bank. with the front tires. the bucket.

Repeat the above steps until the haul unit is loaded

Loading should be from the driver side.

Remember that while these machines are flexible and can dig under very awkward conditions,
the best production is achieved by keeping both the angle of turn and the travel distance to a
minimum. Keep in mind that proper positioning of the equipment that will receive materialfrom
the loader is necessary for maximum production. This cuts down on maneuver time.

LIGHT WHEEL LOADER (SKID STEER LOADER) 131

4.12 Pushing with a Dozer Blade
Bulldozer blade attachments
can be fitted to many types
of outdoor equipment, such
as tractors and skid steers.

Whether it is a conventional
bulldozer or an accessory
blade fitted to a tractor, the
principles by which dozer
blades are operated and used
to move earth are identical.
The only major differences
arise from the platforms to
which they are attached.

While a fully tracked vehicle

like a bulldozer or skid
steer has great traction
and can turn in place, a This difference should always be kept in the operator's mind:
tractor or other wheeled Wheeled vehicles require more room to maneuver and cannot
platform cannot. safely be used on steep slopes, like a tracked vehicle can.

• Lower the blade to the beginning you to remount the

until it is digging of the area you blade to the vehicle
into the soil are trying to clear at an angle, which,
slightly, and start and then remove when added to the
the vehicle forward, another layer. angle created by
pushing the earth Tilting the blade the motion of the
ahead of you. left or right will let cylinders, allows
Always remove you conform it to the blade to reach
earth in relatively the terrain, or help the desired angle.
thin layers (thinner you build the earth
for wheeled into the shape • Always return the
vehicles than for you desire. blade control to
tracked vehicles, hold when the
which have more • Adjust the angle cylinders near the
traction), and be at which the end of their stroke.
careful not to let dozer assembly This allows the
earth collect ahead is mounted to the hydraulic fluid to
of the blade until it vehicle if you need bypass the valve
spills over the top. to angle the blade that controls
When you reach more than you can the cylinders,
the end of a run, with the pistons and greatly
reverse the vehicle alone. This allows reduces wear.

132 LIGHT WHEEL LOADER (SKID STEER LOADER)

4.13 H ow to load a Skid Steer Without Power?
Because most skid steers If not, you need to figure out the best method for moving your
do not have a neutral gear, particular skid steer without damaging the drive shaft or the
loading a skid steer without hydraulic pumps.
power requires some
preparation and planning.

Ultimately, the make and

model of the skid steer you
need to load determines the
method you will use.

If you have access to other

heavy equipment large
enough to carry the skid
steer, you will save yourself
time and labor.

Follow these instructions if you plane to tow a skid steer:

• Attach a 6 meters’ to damage your • Remove the skid

high-test chain to skid steer and steer's driveshaft.
the skid steer's cage requires the least If you remove the
frame. Attach the amount of work. driveshaft, towing
chain to the bucket the skid steer will
of a front-end loader • Remove the drive not damage the
or track-hoe and lift chains using the transmission.
the skid steer. Move required tools. This On some skid
it this way if you will allow you to steers, it is
have access to such pull the skid steer easier to
equipment. without damaging remove the drive
This method is the drive line or shave than the
the least likely hydraulic pumps. drive chains.

Remember:

Towing your skid steer

without properly
disengaging the
mechanical parts can
cause damage to your
skid steer's transmission
and hydraulic pumps.
No owner's manual
will suggest you do so
even for short distances.

LIGHT WHEEL LOADER (SKID STEER LOADER) 133

4.14 How to Work in Wet Sand or Mud?

Using your skid steer efficiently is a complicated job that can take years to learn. It takes a lot
of skill to use these machines to flatten an area without cutting it too dee p or too shallow in
any one spot. Despite the difficulty of operating the machinery with such precision, some core
concepts are very simple:

134 LIGHT WHEEL LOADER (SKID STEER LOADER)

• When working in wet mud. If the dump is • Move slowly and
sand or mud, aim above where the wet methodically to
straight at the dump sand or mud is being avoid slippage and
whenever possible. removed, then break stalls. Traction
This prevents the the ground while means the skid steer
skid steer from moving downhill and is operating at its
turning while push the loose wet most efficient level.
carrying material, sand or mud back Sudden movements
and minimizes up the hill. can cause the skid
the amount of steer to lose traction
wet sand or mud • Dig slots with about and stop or jerk
it will lose when one third of a blade into the wet sand or
the turn is made. It width between them. mud, causing loss
also prevents wear This maximizes the of material and a
on the steering amount of material rutted surface.
components from the skid steer can
rotating the skid carry by preventing • Keep the blade
steer under a wet sand or mud full as much as
heavy load. from slipping around possible. A full blade
the sides of the is easier to manage
• Bulldoze downhill blade. Once the than a partially full
whenever possible slots are finished, one. If you find the
so the weight of the center can be blade is not full
the skid steer helps removed quite easily. when it should be
move the wet sand Don't use slots if then reverse and
or mud. If you push you're dozing on the add more material
uphill, then the skid flat because the push on the pass.
steer has to move its may be too long and
own weight and that the skid steer could
of the wet sand or become stuck.

LIGHT WHEEL LOADER (SKID STEER LOADER) 135

4.15 H ow to Operate Skid Steers in Steep Terrain?
Operating skid steers in steep terrain requires special attention and terrain specific technique
because several dangers are presented by moving machinery over an incline.

Improper loader operation on inclines causes extra unnecessary erosion and waste of both top
and subsurface soil, and it can also cause rock, land and mud slides increasing the danger of
slippage and tipping of the equipment as well as a destruction of any work already completed by
the machinery.

For safe operations, follow these instructions:

How should I go up and down a slope with a full bucket?

Keep the heavy end up!

How should I go up and down a slope with an empty bucket?

Keep the heavy end up!

136 LIGHT WHEEL LOADER (SKID STEER LOADER)

A Skid Steer Dozer in Steep Terrain

• Choose the right • Wear the skid assistance

time to operate steer’s seat in case of
the skid steer belt at all times emergency.
on steep terrain. during operation
Assess the on steep slopes. • Drive slopes
weather, presence Do not operate straight up and
of standing water a loader on a down rather than
and the visibility slope where at an angle or
across the entire other machines sideways. Should
site. Wait to are working the skid steer
begin skid steer on the same begin slipping
operations if any slope at lower downhill, turn
of these factors elevations. This the nose of the
are less than reduces the risk loader directly
optimal. Consider of the skid steer downhill and
also the length rolling or slipping lower the basket
of time needed into the path of or blade to the
for the skid steer other workers. ground. Keep
to finish its task the basket or
and whether • Station a blade in its
environmental supervisor or co- lowest traveling
conditions are worker at a safe position while
likely to worsen distance from moving over
before the where the skid sloping terrain.
loader finishes steer is working
and leaves the on the slope • Operate the
sloped site. and instruct him skid steer on
or her to watch steep slopes
• Stabilize the loader operations in its lowest
slope by first through gear to provide
waiting until any completion maximum control
standing water to provide over the machine.
evaporates and
mud hardens.
Compact any
loose gravel
and remove
boulders that rise
from the slope
surface enough
to tip the dozer
on its side should
individual tires roll
over them.

LIGHT WHEEL LOADER (SKID STEER LOADER) 137

4.16 Accident With Skid Steer
4.16.1 Major Hazards 4.16.2 Hazard Factors

Major hazards of skid loader Operator misjudgment is one of the biggest hazards in skid
usage include being run loader operations. Reaction time of the operator can greatly
over, being crushed between mitigate a dangerous situation, but can often be too long
mechanical parts, trapped by depending on the operator’s age, physical condition and most
loads, or pinned on a rollover. importantly, driving experience.

The operator and workers Gravity also poses a danger when operating a skid loader. For
nearby place themselves example, you should never reach under a hydraulic loader arm.
in danger if they neglect Should a hydraulic line break, gravity will most likely pull the
proper safety. bucket to the ground, crushing the operator's arm and anything
else in its path.

138 LIGHT WHEEL LOADER (SKID STEER LOADER)

4.17 Parking
Skid steer safety is not complete until the loader is parked and secured. Loaders should be
parked on level ground whenever possible. If they must be parked on a grade, the tracks should
be blocked to prevent roll-away. Always shift into neutral and set the parking brake to immobilize
the machine. Lower the bucket and any other attachment to the ground. This will also help
prevent the skid steer from moving.

LIGHT WHEEL LOADER (SKID STEER LOADER) 139

When you have finished studying this chapter, try to answer these questions.

1 Who is in charge for service and maintenance on daily

If you are unsure of the bases on the?
answer, go back and re-read
the relevant section in the
chapter. Please note that the
questions do not cover all of
the content of the chapter.

2 You drive with 3 In what position should 4 Are you allowed to

maximum load in the the bucket have when use the skid steer
bucket, up slopes and you transport loads? bucket for personnel
down slopes, in which lift for example to
direction should the change light bulbs?
load carries in?

5 What do you primarily 6 Why is it important to 7 Which is the best way to

think of when know what type of soil fill the bucket?
lifting pipes? you are working in?

8 After how many hours 9 Which side is the 10 In what position must
is it recommended best side, when you the bucket to be when
to lubricate all load a truck? you leave the skid
grease fittings? steer loader?

140 LIGHT WHEEL LOADER (SKID STEER LOADER)

11 Which is the most 2 What should be the
12 13 Where should the user
important safety distance between the manual be stored?
equipment when bucket and the ground
you drive the skid when travel by asked
steer loader? steer loader?

14 When rotating beacons 15 How does the wheel 16 What are the biggest
shall be used on the loader's stability change risks of accidents for
skid steer loader? when the load is the operator on the skid
lifted high up? steer loader?

17 When you have to fasten 18 In which direction 19 How many centimeters

your seatbelt? you should move above the ground
when doing should be the bucket
leveling operation? when trying to fill?

20 What is the best position for the bucket when doing pushing operation?

LIGHT WHEEL LOADER (SKID STEER LOADER) 141

Chapter Five
LIGHT
EXCAVATOR
5.1 Introduction
Excavators are earth moving equipment used for the purpose of excavation,
loading and lifting light loads.

It can also use crusher, hammer or shear for performing quarry and demolition. They consist
of a boom, bucket and cab on a rotating platform (known as the "house"). The house is placed
on the top of an undercarriage with tracks or wheels, depending on the type of excavator. All
movement, tasks, maneuvers and functions of the excavator are due to hydraulic pumps fueled
by hydraulic oil.

In this chapter, you will study the components, attachments, functions, maneuvers,
safety, maintenance.

144 LIGHT EXCAVATOR

5.2 The Excavator Structure

1. Track/Travel engine 7. Bucket 13. Boom cylinder

2. Track roller 8. Bucket link 14. Cab

3. Idler 9. Bucket cylinder 15. Engine hood

4. Track/Crawler 10. Arm (stick) 16. Counter weight

5. Blade 11. Arm cylinder 17. Platform

6. Swing frame 12. Boom

14 13 12 11

16 15

10

9
17

8
5

1 2 3 4 6

LIGHT EXCAVATOR 145

5.3 The Main Controls
5.3.1 The Travel Levers

The function of both travel levers is to move or make the excavator crawl both forward and
backwards. Pushing both the travel levers forward at the same time will make both the tracks (also
known as “crawlers”) move equally and simultaneously in a forward direction. Pulling both the
travel levers towards the operator, i.e., in a backwards direction, at the same time will make both
the tracks move equally and simultaneously in the reverse direction.

Left Right
travel travel
lever lever

Left Right
operating operating
joystick joystick

Excavators are earth moving equipment

146 LIGHT EXCAVATOR

5.3.2 Left 5.3.3 Right 5.3.4 To Make
Travel Lever Travel Lever a Spin Turn

The function of the left The function of the right To spin left, tilt the left travel
travel lever is to operate the travel lever is to operate the lever backward and the right
left track in both forward right track in both forward travel lever forward. To spin
and reverse directions. By and reverse directions. By right, tilt the right travel lever
moving the left travel lever moving the right travel lever backward and the left travel
alone in a forward position, alone in forward position, the lever forward.
the direction of the excavator direction of the excavator
can be changed to the right. can be changed to the left. By Driving levers when
By moving the left travel lever moving the right travel lever turning the machine
alone in reverse position, the alone in reverse position, the
direction of the excavator can direction of the excavator can
be changed to the left. be changed to the right.

NEUTRAL NEUTRAL

Before operating the travel levers, check to make sure that the
dozer blade is attached to the front of the operator’s seat. Be
aware that when the dozer blade is to the rear of the operator’s
seat, the travel levers operate in the opposite direction to when
the dozer blade is in the front of the seat.
NEUTRAL NEUTRAL

Get rid of hindrance or obstacles in the machine’s path, if any.

Driving Direction

LIGHT EXCAVATOR 147

5.3 The Main Controls
5.3.5 The Operating Levers

The operating levers serve to swing or rotate the upper structure of the boom, arm and bucket.

The left operating lever operates on the arm, and the right operating lever operates on the boom.

148 LIGHT EXCAVATOR

5.3.6 Left 5.3.7 Right Operating Lever
Operating Lever

The left operating lever is The function of the right operating lever is to activate the boom.
used to activate the arm. By pulling the lever back, the operator can extend the boom. In
Pushing the left operating simple terms, operating the right operating lever in backward
lever to the front will close direction will open the boom cylinder and this increases the
the arm cylinder and extend height of the boom from the ground. This function helps to lift
the arm. Pulling the lever the bucket, hammer or any other attachment in upward direction
backwards opens the arm away from the ground.
cylinder and contracts the
arm. This function helps to Pushing the right operating lever in forward direction will lower
fill and empty the bucket. the boom to the ground. In simple terms, it closes the boom
cylinder and brings the bucket or any other attachment closer
The results can be fatal to the ground.
if you allow anyone to
enter the swing radius The right operating lever is also used to activate the bucket
and machine path. Always cylinder. Pushing the right operating lever to the left will open
signal your intention to the bucket cylinder and close the bucket for digging or filling.
move by honking. Pushing the right operating lever to the right will close the
bucket cylinder and open the bucket for dumping.

LIGHT EXCAVATOR 149

5.4 Machine Attachments
Your excavator will be able to function with a variety of bucket types, some of which are
described below, depending on the job required.

5.4.1 General 5.4.2 General 5.4.3 Ditch

Duty Buckets Purpose Buckets Cleaning Buckets

• General duty • General purpose • Shaped for ditch

buckets are a buckets are for cleaning, sloping,
next-generation digging in low- grading and other
bucket design that impact materials finishing work.
loads easily and such as dirt,
efficiently. loam and mixed
compositions. • Drainage holes
• Improved permit easier
structures and • Lighter structures dumping of
wear coverage increase the wet, compact
improves bucket maximum material.
longevity. capacity that can
be loaded.
• Sized for • Compact profile
production • Sidebars are pre- permits working
excavation in drilled for optional in confined areas.
low impact, low side cutters
abrasion materials and sidebar
such as topsoil protectors.
and fine gravel.

Your excavator will be able to function with

a variety of bucket types, depending on the
job required.

150 LIGHT EXCAVATOR

5.4.4 Tilting Ditch Cleaning Buckets

Dual hydraulic centers pivot the bucket up to 45 degrees in either direction.

5.4.5 A tilt rotator (Rototilt)

A tilt rotator (known under

a number of trade names,
particularly Rototilt) is a
hydraulic attachment/tool
used on most excavators,
and backhoes between
3-30 tons in the Nordic
countries (Sweden,
Finland, and Norway).

TILT A tilt rotator is mounted on

+- 40° the excavator such that the
excavator bucket can be
rotated through 360 degrees
and tilted +/- 40 degrees,
in order to increase the
flexibility and precision of
the excavator.

A tilt rotator can best be

described as a wrist between
the arm of the excavator and
the bucket (or whatever other
tool is fitted to the excavator
tool). With its integral quick
coupler and rotary

LIGHT EXCAVATOR 151

5.4 Machine Attachments
5.4.6 Fitting Attachments (Couplers)

Gannon Quick Change Coupler

The “blank hook” design of this type of coupler enables it to attach entirely to the outside of
the bucket for full-bucket capacity. No tools are required to attach it to virtually any type of
compact excavator.

Quick coupler fitted on bucket

REAR FRONT

5.4.7 CF Mechanical Quick Latch Coupler

The CF mechanical coupler offers a lightweight, durable

design for the most demanding coupler requirements.

The coupler design allows a simple method to quickly switch

attachments on a machine.

A manual locking pin securely locks the attachment to the

coupler. These couplers are custom designed to fit most
attachments. Optional jump latches allow machines to adapt
to different manufacturers’ attachments and provide greater Quick coupler
flexibility between machines and attachments on the job site. fitted on Machine

152 LIGHT EXCAVATOR

5.5 Techniques of excavating
An excavator is a key component of any construction site, and the excavator’s operator will be
called upon to perform any number of complex tasks. In this section, we will review some of the
main functions you will be asked to perform with your machine. There are specific techniques
for different operations depending on the terrain and construction site, so you must use your
judgment as you expand your experience operating the machine.

Before digging into the specific functions, there are some general techniques that you should
know and always practice:

• Do not dig while

in motion.

• Do not dig
using the
traveling force.

• Do not let the

bucket free-fall
on the ground.

• Use the hydraulic

cylinders gently
practicing all the
safety measures.

• Do not lengthen It is not allowed while digging to lift any part of the tracks
hydraulic from the ground
cylinders to its
fullest. Always
keep a margin.

• To extend the
machine’s service
life, do not
overload it.

• When digging, do
not fully fork the
bucket into the
ground. Instead,
dig with the
bucket at shallow
levels. This gives
fewer loads on
the bucket.
Breaking down the walls using the swing force not only shortens
the machine life but damages the machine components too.

LIGHT EXCAVATOR 153

5.5 Techniques of excavating
5.5.1 Prohibited Operations

• It is dangerous to
swing the upper
structure while
traveling. If you have
no choice and must
operate the hoe
attachment while
traveling, operate at
speeds slow enough
so you maintain
complete control
of the machine at
all times. It is not
allowed while digging
to lift any part of
the tracks from the
ground

• Do not carry out

breaking operations Never dig or excavate under the machine or stabilizers. It may
using slew (swing) fall into the excavation.
force.
Breaking down
walls using swing
force shortens
the machine’s life
and damages the
machine components
as well.

• Also, you must not

dig the bucket teeth
into the ground when
swinging.
Doing so will damage
the hoe attachment,
bushes and even the
hydraulic cylinder.

• Never dig or excavate

under the machine or
stabilizers. It may fall
into the excavation
You must not dig the bucket teeth into the ground
when swinging.

154 LIGHT EXCAVATOR

5.5.2 Digging Base Rock

• For hard base • When folding the the machine

rock, use the hoe attachment, falling into the
shocking force of be aware of your excavation.
the machine and surroundings
crush the rock up and be careful • Do not start
into small pieces to not hit the traveling when
with a breaker attachment on the stabilizers
before digging. the dozer blade if are still touching
This prevents it is so equipped. the ground.
damage to the Always raise
machine and is • Never dig or the stabilizer
therefore more excavate under enough to clear
economical in the machine or the ground
the long run. its stabilizers. before moving
A cave-in the machine.
could result in

For hard base rock, use the shocking force of the machine and crush the rock up into small
pieces with a breaker before digging.

For hard base rock, use the shocking force of the machine and crush the rock up into small
pieces with a breaker before digging.

LIGHT EXCAVATOR 155

5.6 Traveling Over Obstacles
Traveling over obstacles like rocks may expose
the machine body to strong shocks and result in significant damage.

If driving over the obstacle is necessary, reduce the impact by keeping the attachments of
the machine near to the ground, traveling at low speed, and
going over the obstacle with the center of the crawler.

Reduce the impact traveling at low speed, and going over the obstacle with the center
of the crawler.

156 LIGHT EXCAVATOR

5.6.1 Traveling at Higher Speeds

On bumpy, uneven or uncertain grounds, be sure to travel at lower speeds and avoid speeding,
sudden braking or changing directions quickly.

5.6.2 Traveling on Sloping Terrain

• When traveling • When traveling • When traveling

on sloping on sloping or uphill at an angle
terrain, avoid graded terrain, of 15° or greater
going beyond lower the bucket
the machine’s to a height of 1. Avoid going
stability 20 to 30 cm (8 beyond the
capabilities as to 12 in.) above machine’s
specified in the the ground. If stability.
manufacturer you face an
manual. Keep emergency 2. Lower the bucket
in mind that situation, lower to a height of 20
when working the bucket to the to 30 cm above
area conditions ground and stop the ground.
are poor, the the machine.
machine’s 3. Move slowly.
actual stability • When traveling
capabilities may on slopes or 4. Do not open
be lower than grades, move the door while
indicated in slowly in lowest traveling
the manual. gear at a on slopes
reduced speed.

DOZER BLADE

CLIMBING
0° °
11 90° - 110
°-
90

20-30
cm

0 cm
20-3
DESCENDING

LIGHT EXCAVATOR 157

5.6 Traveling Over Obstacles
5.6.3 Traveling posture

5.6.3.1 Traveling uphill 5.6.3.2 Traveling downhill

When traveling uphill on Lower the engine speed proportionally to the slope of
slopes at an angle of 15° the gradient and travel with your machine’s arm at a 90
or greater, travel with -110-degree angle to the house, as shown in the diagram,
your machine’s arm at a when traveling downhill on slopes at an angle of 15° or greater.
90 – 110-degree angle Opening the door while traveling on slopes is dangerous, as
to the house, as shown the force required to open and close the door can change
in the diagram. unexpectedly.

Always keep the door closed when traveling on slopes.

158 LIGHT EXCAVATOR

5.7 Excavating

• Set the blade (if bucket from coming is strongest when

equipped) on the into contact with the arm and boom
opposite side to the machine. angle are 70° and
the side you want 120° to the ground,
to dig on. • Use the arm and respectively. Use
bucket and dig this angle for
• Digging while facing with shallow, effective digging.
backward, prevent long strokes.
the boom cylinder, The digging force

The digging force is strongest when the boom and arm angle is 70 to 120°.

20°
0°-1
7

LIGHT EXCAVATOR 159

5.7 Excavating
5.7.1 Loading a Truck

• Do not load a truck • Load the truck loading easier

unless its driver is from the rear. and increases the
in a safe place. amount of dirt that
• When loading can be loaded.
• Never swing or dirt in a truck,
position the bucket starting from the • Use a small
over personnel or back of the truck’s slewing angle for
truck cabs. bed makes the greater efficiency.

160 LIGHT EXCAVATOR

5.7.2 Lifting Load

Before lifting, see the manufacturer’s manual for the lifting capacity of your excavator.

• Overloading is hazardous. Make sure you are on solid, level ground before
lifting any load.

• Attach chains and slings to the manufacturer’s designated lifting points.

• Always lower the stabilizers to the ground before lifting. If the ground is soft,
place pads or wood planks under each stabilizer.

• When lifting, be sure the load is properly balanced. Move slowly so that the load
does not sway or swing around.

Always lower the stabilizers to the ground

before lifting.

LIGHT EXCAVATOR 161

5.8 Procedures and Checklists
In this section, we will review the typical procedures in the start-up and shut-down of your
machine, including a list of components to check before starting to put your machine to work.

5.8.1 Starting up your machine

• Do not ignite and lower body the engine.

the engine or leaned deeply
start operations against the seat. • Never persist
until you are to operate the
properly seated. • Make sure that starter motor
there are no for more than
• Adjust the control people within 15 seconds.
lever of any work your working
equipment and circumference. This practice
make sure the will damage the
operator's seat is • Never attempt to starter motor.
in a comfortable start the engine
position for you. by reaching from If the engine
outside the cab does not ignite,
• Operator or by switching return the
should be able it on while still key to the off
to operate standing on position and
the operation the ground. try again after
lever and pedal 30 seconds.
satisfactorily
with his back • Now, fire up

5.8.2 After Starting the Engine

• Warm up the engine and • Listen for unusual noises.

hydraulic fluid.
• Test the engine’s speed control.
• Observe all gauges or
warning instruments for proper • Operate each control to insure
operation. proper operation.

Never attempt to start the engine by reaching

from outside the cab or by switching it on
while still standing on the ground.

162 LIGHT EXCAVATOR

5.8.3 Sample Excavator Checklist
Operator/Inspector Date Time

What are you inspecting? What to look for

FROM THE GROUND
Bucket, GET Excessive Wear or Damage, Cracks
Bucket Cylinder & Linkage Excessive Wear, Damage, Leaks, Lubricate
Stick, Cylinder Wear, Damage, Leaks, Lubricate
Boom, Cylinders Wear, Damage, Leaks, Lubricate
Underneath Machine Final Drive Leaks, Swing Drive Leaks, Damage
Machine Body Cracks, Damage
Undercarriage Wear, Damage, Tension
Steps and Handholds Condition and Cleanliness
Batteries & Hold Downs Cleanliness, Loose Bolts & Nuts
Windshield Wipers & Washers Wear, Damage, Fluid Level
Fire Extinguisher Charge, Damage
Engine Coolant Fluid Level
Primary/Secondary Fuel Filters Leaks, Drain Water Separator
Air Filter Restriction Indicator
Hydraulic Oil Tank Fluid Level, Damage, Leaks
Hydraulic Oil Filter Leaks
Radiator Fin Blockage, Leaks
Hydraulic Oil Cooler Fin Blockage, Leaks
AC Condenser Fin Blockage, Leaks
Lights and Mirrors Damage
Engine Oil Filter Leaks
Overall Machine Loose/Missing Nuts, Bolts, Loose Guards, Cleanliness
ENGINE COMPARTMENT
Engine Oil Fluid Level
Swing Gear Oil Fluid Level, Leaks
Swing Drive Pinion Grease Water
Fuel Tank Fuel Level, Damage, Leaks
All Hoses Cracks, Wear Spots, Leaks
All Belts Tightness, Wear, Cracks
Overall Engine Compartment Trash or Dirt Buildup, Leaks
INSIDE THE CAB
Seat Adjustment
Seat belt & Mounting Damage, Wear, Adjustment, Age
Horn, Travel Alarm, Lights Proper Function
Indicators Proper Function
Monitor Panel Proper Function
Switches Proper Function
Travel Controls Correct Operation
Mirrors Adjustment
Heating and Cooling System Proper Function
ROPS Damage, Loose Mounting Bolts
Overall Cab Interior Cleanliness

For more information, please refer to the operation and maintenance manual or any other applicable manuals and instructions for
your machine.

LIGHT EXCAVATOR 163

5.8 Procedures and Checklists
5.8.4 General Precautions

Safe operation of your excavator is an essential part of your training and day-to-day role as an
operator. In this section, you will review the general precautions you should take as well as the
specific safety issues concerning your excavator.

Remember

• Operators must travel to the • Workers must be

be seated inside work site. careful to avoid
the cab with the job conditions
seatbelt buckled • Excavator bucket that could lead
before starting and attachments to rollover when
the excavator. need to working on
remain close piles, slopes,
• Never start to the ground hills and when
the excavator while moving. crossing ditches.
while standing
on the tracks • Keep a safe If the excavator
outside the cab. distance from begins to slide
the edge of sharp on a steep grade,
• Operators should drops, slide slow down and
verify that all areas or electric turn downhill.
controls function power lines.
properly as they

5.8.5 Work site Visibility

• Clean the floor surface, levers, • When visibility is low due to harsh
handrails, windows, and lights to weather conditions, avoid operating
ensure good visibility. the machine until the conditions
have improved.
• If the cab windows are broken,
do not perform operation under • When working in poor visibility, turn
any circumstances, as dust and on the machine’s lights or provide
other could enter extra lighting at the work site
the cab area. as required.

Safe operation of your excavator is an

essential part of your training and day-to-day
role as an operator.

164 LIGHT EXCAVATOR

5.8.6 Seatbelts 5.8.7 Riders on the Machine

Seatbelts must always Do not allow anyone to ride on any part of the machine at any
be used by the excavator time while operating or traveling.
operator so that he or
she is confined within the
structure in the event of a
roll-over or tip-over.

5.8.8 Know the Working Area

Before commencing operation, be aware of your working area to ensure safety, as follows:

• You must check • Note and avoid • Check with the

the topography all hazards and local utilities
and the ground obstructions service providers
condition of the such as ditches, to locate any
area where you are underground buried gas and
working. If working lines, trees, cliffs, water pipes or
indoors, check overhead electrical power cables.
the structure of wires or areas Determine
the building. where there is jointly with
danger of sliding. the authorities
what specific
precautions
must be taken to
avoid danger.

LIGHT EXCAVATOR 165

5.8 Procedures and Checklists
5.8.9 Overhead Clearance

• Check overhead from overhead prohibit or restrict

clearance to power lines. unauthorized
know the height entry.
with which you • When working
can maneuver. on roads, make • When working in
If possible, get sure you have water, check the
electricity to any considered depth and solidity
overhead lines pedestrians and of the ground, and
disconnected. other vehicles make sure the
If not possible, around the ground is strong
request a person machine. Use enough to bear the
to signal to you a flagman and machine weight
for guidance so signals while and that the water
that at least the maneuvering. is not deeper than
minimum distance the permissible
required by law • Fence off the depth.
can be maintained working area and

166 LIGHT EXCAVATOR

5.9 Excavator Hand Signals

Swing left Swing right This far to go

Counter rotate Counter rotate Open bucket

Close bucket Dipper in Dipper out

NO
RESPONSE
SHOULD BE
MADE TO
UNCLEAR
Emergency stop Stop engine SIGNALS

LIGHT EXCAVATOR 167

5.10 Parking the Machine
5.10.1 Engine Shutdown

It is not advisable to stop

• Stop the relieve system the engine suddenly when
machine using pressure. operating the machine
the service with heavy loads or at high
brakes (if so • Remove speeds. Doing so may cause
equipped). engine key. the engine to overheat or
seize up. Never shut off the
• Swing the • Shut off master engine suddenly.
machine to align electric switch
the excavator (if so equipped).
with the
undercarriage. • Lock the cab.

• Engage the
swing lock. 5.10.2 Parking

• If the
machine has • Set the left and right travel levers to the
attachments, neutral position.
lower them to
the ground or • Return the throttle lever and idle the engine at
place them in a low speed.
secure position.
• Lower the bucket and dozer blade to the ground.
• Shift controls to
neutral/park. • Raise the safety lock lever to engage the lock.

• Engage • Stop the engine and remove the key.

parking brake.

• Idle engine at
low RPM to
cool down, as
instructed in
the manual.

• Switch off
the engine
by turning
the ignition
switch to stop.

• Cycle all
hydraulic
controls to

168 LIGHT EXCAVATOR

5.10.3 Before leaving the cab

Make sure you have locked the following:

• Cab door • Engine hood • Manual

storage
• Fuel filler cap • Tool case compartment

LIGHT EXCAVATOR 169

When you have finished studying this chapter, try to answer these questions.

1 What is the main use of an Excavator?

If you are unsure of the
answer, go back and re-read
the relevant section in the
chapter. Please note that the
questions do not cover all of
the content of the chapter.

2 How do you make a 3 What is the danger 4 What part of the

center turn (spin turn)? when you make Machine’s aggregate is
a (spin turn)? used to fill the Bucket?

5 What is the purpose of 6 What is the most 7 How should you be

the “Safety Lock Lever”? important measure to take positioning the Crawler
before you start digging aggregate when
with the Machine? moving the machine?

8 How do you primarily do 9 What is the most 10 Why should you not run
if the Machine cannot important step after you the starter for more
manage to dig? restart the Machine? than 15 seconds?

170 LIGHT EXCAVATOR

11 Which measure is the most important when parking the Machine?

2 What should be the

12 13 What must be 14 What could be a risk
angle between the checked before a lift if you turn the House
Boom and the Stick with the Machine? while moving?
when you dig?

15 What should you do 16 What should you 17 How do you adjust the
if you hear abnormal always check before Track tension?
noise from the Machine you begin to dig into
when you dig? unfamiliar areas?

18 What is not allowed 19 Why should you 20 How much must the
while digging? not dig close to security distance from
your own Machine? the excavator be at least?

LIGHT EXCAVATOR 171

Chapter Six
LIGHT ROAD
ROLLER
6.1 Introduction
Road rollers are light mechanical equipment widely used on construction sites.

It is a type of compactor machine designed to compress soil, gravel, concrete, or asphalt in the
construction of roads and foundations. It consists of a large barrel, often made of steel, that
acts as the wheels on a tractor-style machine maneuvered by an operator.

Rollers are sometimes also called steam rollers, regardless of the method of propulsion. This in
particular applies to the largest examples of rollers, used for making roads.

6.2 Machine structure

7
6

3 4
2
5

1. Engine 3. Steering cylinder 6. Roller drum

compartment
4. Articulation pin 7. Scraper
2. Driving wheels
5. Hydraulic engine

174 LIGHT ROAD ROLLER

6.3 Instruments and controls

1. Steering Wheel 8. Hydraulic Oil 13. Accumulator

Thermometer Charge
2. Travel Controller (Optional) Control Lamp

3. Vibration Switch 9. Operated- 14. Brake

Hours Counter Alarm Indicator
4. Traveling Speed
Controller 10. Fuel Level 15. Engine
(Selector) Indicator
(Optional) 16. Overheating
5. Throttle Controller Indicator
11. Speedometer
6. Ignition Box (Optional) 17. Minimal Fuel
Level Indicator
7. Motor 12. Engine Lubrication
Thermometer Control Lamp 18. Air Filter
(Optional) Fouling Indicator

19. Hydraulic Oil Filter

Fouling Indicator

10 7 11 26 9 8 20. Vibration
ON Indicator

21. Hydraulic Oil

Overheating
Indicator
16 15 14 13
17 22. Vibration
Amplitude
18 selector
12 25
23 24
23. Heater Fan Switch
19 20
21 22 6 3 (Optional)
5
1 2
24. Headlights
Switch

25. Rear
Lights Switch

26. Alarm Horn

Pushbutton
4
27. Fuse Block

LIGHT ROAD ROLLER 175

6.4 Types of Rollers
When asphalt is first laid on a surface such as a driveway or street, it is usually porous
and expanded.

Rollers are subsequently used to compact the asphalt before it cools and hardens. There are a
variety of rollers to choose from, depending on the required function.

6.4.1 Single Drum Roller

Single drum rollers provide

extraordinary safety and
excellent compaction
performance. The modern
design of the heavy-
weight single drum rollers
guarantees high efficiency
and results under even tough
working conditions.

High compaction quality with

a low number of compaction
runs means that this is
the most efficient model
on the market.

6.4.2 Tandem
Asphalt Rollers

Tandem Asphalt Rollers are

also known as double drum
asphalt rollers.The machine
consists of two large
barrels on the tractor frame.
Tandem asphalt rollers
come in various sizes and
can be used on driveways,
sidewalks, streets, parking
lots and industrial sites.

Rollers are
used to
compact the
asphalt.

176 LIGHT ROAD ROLLER

6.4.3 Vibratory Steel
Wheel Rollers

Vibratory rollers are made

of steel and can be used in
tandem roller machines.

Depending on the size of

the job and the density of
the asphalt, using a
vibratory steel wheel roller
may be more effective since
the machine includes
vibratory drums that add
extra weight to the rollers'
pressure against the
ground, resulting in
greater compacting.

6.4.4 Pneumatic
Tire Rollers

Pneumatic tire rollers look

similar to tandem asphalt
rollers, except that they have
a row of tires in the front and
back of the machine instead
of two steel barrels.

Pneumatic tire rollers

usually have a single row
of five tires in the front and
another row of five tires in
the rear. These tires can
be driven over asphalt to
compact it down to a desired
density. Pneumatic tire
rollers are usually used on
highways, airport tarmacs
and municipal roads to
compact asphalt.

LIGHT ROAD ROLLER 177

6.4 Types of Rollers
6.4.5 Three-
Point Rollers

Similar to the double drum

roller, three-point rollers are
manually operated devices
that use three steel drums
or barrels as its wheels,
with two at the rear of the
machine and one large barrel
at the front. Three-point
rollers can come with a
"cutting attachment" located
near the outer area of one
of the rear drum s. This
attachment cuts a "joint,” or
a straight line border, in the
warm asphalt as the three-
point roller compacts it to a
desired density.

6.4.6 Pad Foot

Drum Roller

A pad foot drum roller

is a static tamping roller
especially well-suited for
the compaction of silt, silty
soils and clay.

The machine works with

heavy weight and high
speed, creating a strong
impact force through the
pad foot drums.

178 LIGHT ROAD ROLLER

6.5 Vibration button
If your roller is the vibratory
type, then you can activate
the vibratory action by
pressing the vibratory
pushbutton switch mostly
located on the travel control
lever depending on the
manufacturer and model
of the machine.

6.5.1 Vibratory amplitude

Low amplitude High amplitude Do not operate the vibratory

Low amplitude is used when High amplitude is used when system on high amplitude
the thickness of the material is the thickness of the material after obtaining the
less than 250mm (10inch). is more than 250mm (10inch), required compaction
Low amplitude is used to or when there is demand
prevent sewer systems of higher compacting
or water systems from force in order to get the
damage when they are required compactness.
not deep enough. 0

0
0

LIGHT ROAD ROLLER 179

6.6 Techniques for Rolling
6.6.1 How to Roll an Asphalt Mat?

Asphalt must be compacted to ninety-five percent in order to provide a durable, smooth mat for
vehicle traffic. Compacting the asphalt mat is known as "rolling," whether it is done with a double
drum roller or other type of compactor.

6.6.1.1 Step by step:

• Fill the compactor's • Shovel several the handle, and

fuel tank with square feet of gently guide the
gasoline, and the asphalt into the compactor forward
water tank with area to be paved. over the area
plain water. This of asphalt.
water can come • With the throttle
from a garden set on low, pull the • Have someone
hose or some other cord on the plate shoveling asphalt
unpurified source. compactor to start a few square feet
the engine. at a time in front
• Move the of the compactor.
compactor into • Slowly open the Continue until
position behind the throttle on the the entire area
area where you will compactor. Place is paved and
begin paving. your hands on compacted.

180 LIGHT ROAD ROLLER

6.6.2 How to Roll an Asphalt Mat behind the Paver?

Asphalt is a common surface for roadways, parking lots and driveways.

The finished asphalt surface is known as the asphalt mat. Most municipal regulations state that
all roadways must be compacted to about 95 percent. The paver itself will compact the asphalt
to between 75 percent and 85 percent. Double-drum roller machines are used to compact and
smooth the asphalt the remaining 10 to 20 percent. The same regulations serve as guidelines for
paving private drives and parking lots.

LIGHT ROAD ROLLER 181

6.6 Techniques for Rolling
6.6.2.1 Step by step:

1. Prepare the paver 4. Follow 2 to 2.5 will remove any

to lay the asphalt. meter behind the indentations left by
Line up the 5-ton paver with a 5-ton the paving process
double drum roller double drum roller, and ensure a clean,
behind the paver. compacting the smooth surface.
asphalt with the This machine
2. Place a smaller flat rollers. Stay should follow no
machine, a 1-to close behind the more than 4.5 to 6
2-ton double drum paver, because the meter behind the
roller, directly behind compacting of the 5-ton one.
the 5-ton roller. asphalt must be
done with the mat 6. Remove all
3. Make sure all at a temperature machinery from
machines are in greater than the surface of the
place before paving 175 degrees asphalt and allow
begins, because Fahrenheit. cooling and curing
you must begin for 8 to 12 hours
to roll the asphalt 5. Follow the 5-ton before use. Apply
mat as soon as the double-drum asphalt sealer
asphalt is excreted roller with the if desired.
from the paver. smaller machine.
This machine

182 LIGHT ROAD ROLLER

6.7 Operating on sloping ground
When driving or operating
your roller on sloping ground
or near an edge, you must
try to keep a minimum of
2/3 of the drum width on
solid ground. Keep in mind
that the machine's center
of gravity moves outwards
when steering.

For example, the center of

gravity moves to the right
when you steer to the left.
This impacts how much of
the drum width you should
keep on flat ground. Where ≥ 2/3
possible, avoid driving across
slopes. Drive instead straight
up and down sloping ground. Position of drum when driving near an edge

6.7.1 Maximum machine tilt angle

The maximum angle at which

you can safely operate a
roller is about 20 degrees
(see diagram). This angle is
OK OK
calculated assuming a hard,
flat surface with a stationary
roller. The steering angle is
zero, the vibration is switched
off and all tanks are full.

However, conditions are rarely

this perfect. Always take
into consideration that lose
ground, steering the machine,
vibration on, machine speed
across the ground and raising
the center of gravity can It is always safer to
all cause the machine to operating the machine up
topple over at smaller slope and down the slope rather
angles than 20 degrees. It is than operating or traveling
recommended that ROPS (Roll across the slopes.
Over Protective Structure) or
a ROPS-approved cab is used Operating on slopes
20°
when driving on sloping or Max 20° or 36%
unsafe ground.

LIGHT ROAD ROLLER 183

6.8 Procedures and Checklists
In this section, we will review the typical procedures in the start-up and shut-down of your
machine, including a list of components to check before starting to put your machine to work.

6.8.1 Test controls

• Make sure the • Check the • Check the

engine is running Parking drums/wheels
correctly. With Brake and for damages.
the transmission service brakes
in neutral, test according to the • Check service and
engine speed manufacturer’s parking brakes for
control. Operate Manual. proper operation.
each equipment
control lever • Test steering • Perform all
to make sure right and maintenance
all functions left while procedures
are correct. moving slowly. outlined by the
manufacturer of
• Operate the • Check for your machine.
Shift Control to damage,
ensure correct broken or • Check the
operation in missing parts. hydraulic system
forward, neutral Make necessary and repair
and reverse. repairs. any leaks.

184 LIGHT ROAD ROLLER

6.8.2 Sample Checklist

Operator/Inspector Date Time

Was procedure step completed properly? Evaluator Comments

STARTING THE MACHINE

Turn the battery disconnect switch to ON (if equipped)
Engage the parking brake
Adjust seat, adjust mirrors, fasten seat belt
Move direction control lever into neutral
Ensure all tools are grounded
Move the attachment control levers to HOLD
Ensure all personnel are clear of machine
Sound horn
Use ether start aid switch if necessary (per OMM-Operation and Maintenance Manual)
Turn start key switch to ON
Perform startup test or observe monitoring system self-test (if applicable)
Turn start key switch to START. Crank engine

MACHINE WARM UP
Allow machine to warm up (per OMM)
Engage and disengage attachment controls to help speed warm-up of hydraulic components
Cycle all controls to allow warm oil to circulate through all hydraulic cylinders and lines
Perform steering, service brake, and parking brake operation checks (per O&MM by
machine model)
Check secondary steering operation (if equipped)
Check gauges, indicators, and action light frequently

MOVING THE MACHINE

Ensure area is clear
Raise all lowered implements
Depress service brake pedal
Release the parking brake
Move transmission control lever to desired direction
Release service brake pedal and depress accelerator pedal

LIGHT ROAD ROLLER 185

6.8 Procedures and Checklists
6.8.3 Know the Working Area 6.8.5 Pivot area

Before commencing operation, be aware of your working area Do not enter or rest any part
to ensure safety, as follows: of your body in the “HINGE”
area or other “PIVOT” areas
of an articulated machine
• Check for the • Observe the flow like waist-steered Rollers
location of of traffic. while the machine is turning
sloping ground. or the engine is running
• Check for thick there is a high risk of
• Check the dust, smoke or fog. squeezing in the waist
conditions and
direction of travel • When working
of haul roads. on public roads,
make sure you
• Check for holes, have considered
mud or other the pedestrians
obstructions and other
vehicles around
the machine.

6.8.4 Danger Zones

Unless it is essential to the task, all personnel should stay

away from all sides of the Roller while it is in use. Danger
zones include (but are not limited to):

• Terrace • Overhead hazards

(i.e. overhead
• Overhang utility lines,
and overhead
• Trenches or any piping/cable

Before
other sort of trays, etc.)
excavation

commencing
• Working over or
• Blind spots and/ around existing

operation,
or areas of limited underground
visibility facilities

• Swing radius • Stone coated area be aware of

• Travel path • Close proximity your working
area to
of moving
• Under suspended equipment

ensure safety
or overhead loads

186 LIGHT ROAD ROLLER

6.8.6 Overhead Clearance

• Never approach power lines with • When operating the machine in

any part of your Machine unless narrow and limited areas, know
all local or state required safety your machine dimensions, know
precautions have been taken. Use what clearances you will encounter.
extreme caution.

LIGHT ROAD ROLLER 187

6.9 Roller Hand Signals

! STOP
!
STOP Attention Beware of danger

Drive away with the Machine Slow forward drive-to me Slow backward -drive-away
from me

Driving on the right Driving on the left Short motion

Engine start Engine shut down

188 LIGHT ROAD ROLLER

6.10 Machine shut down
Never park the machines on
any part of the road.

• Park the machine

on smooth
level area

• Set parking brake

• Lower all
hydraulic
implements

• Run engine at
low idle for 5
minutes to allow
engine to cool

• Turn start key

switch to OFF
and remove key

• Dismount
machine using
3-point contact

• Block wheels
and remove
disconnect
switch key if
parking for
extended period

• Drain water
from air tank,
if equipped

• Conduct post-
operation
walk-around
inspection

LIGHT ROAD ROLLER 189

When you have finished studying this chapter, try to answer these questions.

1 What is the main use of a Roller?

If you are unsure of the
answer, go back and re-read
the relevant section in the
chapter. Please note that the
questions do not cover all of
the content of the chapter.

2 When should 3 At what job suits a 4 What are the

the "Vibrator "Triple Roller" best? advantages of using
function" be used? a Roller for e.g. road
construction?

5 What should the 6 What is the biggest 7 What type of engine is

operator of the Roller be risk with waist- the most common in
most attentive upon? steered Rollers? modern Rollers?

8 When should smaller 9 At what angle of slope 10 What type of surface

Rollers be used? inclination should you should you avoid driving
avoid driving a Roller? a Roller on if possible?

190 LIGHT ROAD ROLLER

11 What is the advantage of using a pneumatic Roller?

2 How deep compacts a

12 13 How deep compacts a 14 Which of the following
Vibrator Roller set with Vibrator Roller set with injuries are most
low amplitude? high amplitude? common among the
Roller operators?

15 What can happen 16 Which Protective 17 Which control

if you turn abruptly Equipment is the most system is most
with the Roller? important when you common on modern
run the Roller? Rollers nowadays?

18 How much of the 19 How much of the 20 What is the normal

asphalt surface asphalt surface distance between the
is compacted is compacted Paver and the Roller?
by the Paver? by the Roller?

LIGHT ROAD ROLLER 191

Chapter Seven
LIGHT CRANE
(TRUCK MOUNTED
CRANE)
7.1 Introduction

Truck-mounted cranes are these types of machines. into place on the back of
used for loads that fall You need to perform the trucks. But in rural areas
between what you are able to work safely, for you as well where the ground is not
move with muscle power and as for others around. level or where large trucks
those that require a mobile cannot travel, the truck-
or tower crane to be moved. It is designed for the lifting mounted cranes cannot be
or transferring of smaller used. Instead.
The truck-mounted crane's material like: Soil, building
versatility can bring you into material, Machinery, Sand Training is required to operate
unexpected environments and a lot of other lose or any type of cranes. But
and operating conditions. packed materials. operating a Truck Mounted
It is important to have a Crane has some added
large amount of imagination In large buildings, cranes difficulties which requires
and creativity on the job. It are used to move materials learning and specific training.
is equally important to be to the top floors. In a city in how to maneuver the piece
clear about the laws and setting, cranes are stationary, of equipment.
regulations applicable for and are carried and moved

194 LIGHT CRANE (TRUCK MOUNTED CRANE)

Important

This chapter covers safe practices for light cranes. If your machine is equipped with other
devices or special accessories, read the manufacturer’s operating and safety manuals pertaining
to that specific equipment before using it.

7.1.1 Background

Before 1870, cranes were

fixed to a single position,
except for some cranes
which were fixed onto
railway vehicles, which
provided some movement.

Steam-powered cranes were

shown in Paris, France by
the British Appleby Brothers
in 1867 and Vienna in 1873.
In 1922, Henry Coles, who
was the manager of Appleby
Corp began producing truck-
mounted cranes marketed
under the name "The Petrol
Electric Lorry Crane." In 1939
the Coles was acquired by
Steel and Co. Ltd. Wire Crane

Major steps in development

included the adoption
of the IC engine as
well as the invention of
telescopic jibs 1922.

Before 1960, cranes

carried additional booms
to increase the height,
which increased the
operating costs. In 1959
crane expert R.H. Neal,
hydraulics specialist F.
Taylor, and design director
Bob Lester integrated all of
these developments, hence
modernizing the cranes.

The Coles Hydra Speed Knuckle-Boom Crane

LIGHT CRANE (TRUCK MOUNTED CRANE) 195

7.1 Introduction
crane appeared in 1962, Johnny Johnson several state-of-the-art
further modified with the 10- who started a new developments.
ton fully telescopic hydraulic manufacturing processes
boom in 1966, followed in plant. With backing from Unlike most cranes, the
1968 by the 30-ton "Husky" the British Crane Hire operator must move around
military versions with Corporation they acquired the vehicle to be able to
four-wheel drive. a small factory unit and overview his load; hence
ordered every single element modern cranes may be
In 1972, Steels was forced of their products from fitted with a portable cabled
to merge with the A Crow subcontracted suppliers. or radio-linked control
Group, losing some of their system to supplement the
most valuable employees, In 1976 the Cosmos team crane-mounted hydraulic
including Lan Hassel and had created a 25-ton crane, control levers.
which brought together

Radio-linked Control

196 LIGHT CRANE (TRUCK MOUNTED CRANE)

7.2 Machine structure

18
1

4
2

16

9
10

11

12

17 13

14

15
8

3 6 5

1. Boom 8. Outrigger 13. Outrigger control

lever (Street side)
2. Column 9. Boom topping
control lever 14. Outrigger control
3. Base lever (Curb side)
10. Winch
4. Hoist winch control lever 15. Hook block

5. Slewing gear 11. Boom 16. Warning horn

telescoping
6. Topping cylinder control lever 17. Wire rope

7. Telescoping 12. Swing 18. Boom

cylinder control lever angle indicator

LIGHT CRANE (TRUCK MOUNTED CRANE) 197

7.3 Crane controls

Crane remote controls

Crane lever controls

198 LIGHT CRANE (TRUCK MOUNTED CRANE)

 RIGHT

LEFT

LOWER

RAISE

LOWER

RAISE

OUT
(EXTEND)

IN
(RETRACT)

LIGHT CRANE (TRUCK MOUNTED CRANE) 199

7.4 Crane Attachments

1. Universal Fork 2. Pallet Forks 3. Augers

4. Peel Grapples

200 LIGHT CRANE (TRUCK MOUNTED CRANE)

7.5 How to operate the crane?
When you get to work, remember to think and consider before every action. Inspect, control and
ask questions!

Before you can get to work, there are some important basic conditions that you should establish.

Truck mounted crane ready for stable lift.

7.5.1 Basic Conditions

• Your crane stability • You should ensure supervisor on

can be seriously that ground site. If you are
affected if you are conditions are safe. not satisfied, talk
driving or operating If you are unsure, to your company
on unstable ground. seek contact with before you start
the responsible operating or lifting.

LIGHT CRANE (TRUCK MOUNTED CRANE) 201

7.5 How to operate the crane?
7.5.2 Location of crane

The surface pressure between the leg-plate and base should not exceed 5 kp/cm².

Check for the following ground conditions:

• Uncompressed • Basement and • Underground

fill, such as soil or floors. These cables, such as
other fill material. may be too weak sewers, drains,
Cracks in the to withstand the wells, gas and
ground may weight of your water pipes, etc.,
indicate an crane with or can be damaged
uncompressed without a load by the crane's
filling. and a disaster weight and can
can occur cause crane break-
without warning. down or tipping.

The surface pressure between the leg-plate

and base should not exceed 5 kp/cm².

202 LIGHT CRANE (TRUCK MOUNTED CRANE)

7.5.3 Out riggers

• Check the
ground next to
the trench edge
before setting up
the crane.

• Do not add
the legs or
ride mobile
crane closer to
the edge of a
trench than a
distance equal
to the depth of
the excavation
unless the
excavation edge
is tongued.

• Make sure
that your
crane is level.

• Whenever
possible, use
the leg-plates
etc. so you get a
solid platform.

Weather conditions (e.g.,

violent and prolonged rain)
can change the basic

Conditions of the ground

and cause the crane to fall.

You should be aware of

this and ifcircumstances
change, control or adjust
the crane level.

LIGHT CRANE (TRUCK MOUNTED CRANE) 203

7.5 How to operate the crane?
7.5.4 Begin Lifting

Lifting loads with your crane is the most basic and common operation.

• Determine the
weight of the
load from a
safe source
(e.g. marked
weighty weight
delivery or
shipping note).
Do not forget to
add the weight
of the crane
blocks, slings,
lifting beams,
shackles jib, etc.

• Set up the
mobile crane in
level and make
sure everything
is prepared
(base deployed,
legs extended,
overload
protection
connected, etc.).

• Remember One of the most common and limit switches that are
that you must causes of crane accidents fitted with light and/or audio
always ensure is overloading. Always be warnings, so be sure to
a sufficient aware of the lifting capacity take careful note of them.
safety margin of your crane. You must Understand and respond
when lifting. know the weight of the load immediately to any alerts
and be sure that the load from these switches.
• Make sure the remains within the lifting
area is clear of capacity during hoisting. However, remember that
people, vehicles they are there solely as an
and obstacles. Make sure the circuit aid for your assessment,
Check this breaker is properly and not as a replacement
regularly in adjusted and tested for the for it. Make sure the area
between the lift conditions that apply. Your is clear of people, vehicles
crane will come equipped and obstacles. Check this
with overload protection regularly in between the lift.

204 LIGHT CRANE (TRUCK MOUNTED CRANE)

7.6 Control at coupling and strapping 7.7 Lifting
accessories
Your duties as a crane Lifting accessories must be Safety
operator demands that properly connected to the precautions
you are positioned at your load. Any piece of cargo
cranes controls. that can potentially fall off
or turn out during hoisting
Therefore, it should be or lowering must be safely • Keep the straps
someone else that should secured before lifting. clean and
be strapping the load lubricated.
(an assistant). Your cranes hoists should
be either equipped with an • Keep the
Therefore, make sure that effective lock-hook or be slings stored
the assistant is competent designed so that the load by hanging
for his task. cannot slip out of the hook. them in the
appropriate tray.
Lifting accessories Lifting points and
that you are going to connection points on the • Never exceed
use must be approved load (if any) should be the specified
and inspected. stated, as far as possible. maximum
load for each
top angle.

• Make sure the

load is as far as
possible and is
symmetrically
distributed.

• Avoid sharp jerks

when lifting.

• Never use
defective slings
- deformed
press locks,
splits, kinks in
the rope, or wire
breakage should
be discarded.

• Never tie ropes.

Never exceed the specified maximum load for

each top angle.

LIGHT CRANE (TRUCK MOUNTED CRANE) 205

7.7 Lifting accessories Safety precautions
7.7.1 Wire Rope Precautions

Wire rope can be the weak link in crane safety. It is exposed to heavy loads, cut, sharp bends,
extreme weather, chemical attack and other forces which can reduce its reliability, so Inspection
and maintenance of wire is crucial to ensure safe working conditions.

• NEVER shock
a wire rope
with load.

• AVOID formation
of wrinkles.
Entanglement
will cause
serious
weakness
in the wire.

• DO NOT pull the

rope over a non-
rotating support.
The wire cuts
like a knife

• DO NOT
purposely
knot the wire.

• NEVER overload
a wire rope.

Wire rope
can be the
weak link in
When lowering the hook If the winch rope twines
block, leave at least two and the hook block rotates,

crane safety.
turns of the winch rope on fully untwine the rope before
the winch drum. lifting any loads.

206 LIGHT CRANE (TRUCK MOUNTED CRANE)

Replace the entire wire rope if the following conditions exist:

• When there are either three broken wires in • When flat spots
one strand or a total of six broken wires in all on the outer wires
strands together. appear significantly.

1 2 3 4 5 6

1 2 3 4 5 6

• A decrease or increase diameter or a dent damage indicates a core failure.

NOTE!
Maximum top angle is 120 °.
Use shims at sharp corners.
Reduce maximum load by
20% at wide top angles.

120°
The maximum
MAXIMUM
peak angle at a
LOAD
loop lift is 120
degrees.

LIGHT CRANE (TRUCK MOUNTED CRANE) 207

7.7 Lifting accessories Safety precautions
7.7.2 Marking

Examples of identification tags for single and multiple chains/straps.

Wear test of the nominal Assembly - number of Chain diameter

diameter with indication legs (multiple-leg)
of minimal
diameter (-10 %)

Space for
identification
Engraving number
the next
test date

VIP WLL
(single-leg) VIP WLL with indication
of inclination angle

Chain pitch gauge testing for Testing of plastic

pitch elongation caused by elongation caused
wear of nominal diameter by overloading

Testing wear of nominal diameter Testing of plastic elongation Testing of pitch elongation caused
caused by overload by wear of nominal diameter

208 LIGHT CRANE (TRUCK MOUNTED CRANE)

7.7.3 The bending diameter impacts on the maximum load

Wire rope factories

recommend that • Chains and • Remember that
consideration is given slings must not the slings of
to the fact that slinging have kinks. synthetic materials
viability decreases as can be damaged
the bending diameter • Use shortening by abrasion,
decreases. If the cable is hooks on distention and
bent around a shaft, for shortening chemical attack.
example, having the same of chains.
diameter as the rope, the • Use abrasive
carrying capacity will be protection if it
reduced to only 50% of is possible.
the original.

d
d d
d d d

6d 5d 4d 3d 2d 1d

100% 85% 80% 70% 65% 50%

7.7.4 Unbalanced load

• Determine the load • Test lifting the load

weight (including by lifting it off the
cargo accessories). ground. The part of
the load that tilts
• Set the crane so that (slopes) towards
the load is within the the ground is
working radius. the heaviest.

• Position the crane • Move the crane

hook over or near hook or strap the
the assumed center load differently for
of gravity. correction.

• Strap the load. • Make a new

attempt to hoist.

Continue in this manner until the load is in balance.

DESIRED LIFT ANGLE

Make sure you know the real before you lift.

LIGHT CRANE (TRUCK MOUNTED CRANE) 209

7.8 Lifting

• Outriggers must • Where lifting and • Avoid the "jerk"

normally be lowering work in the load. It can
fully extended is completely cause damage
and locked. or partly out of to the crane
your sight, you structure and
• You must ensure must be sure to the crane may
that the crane is get signals from overturn.
level, both along the authorized
and across the person who can • If possible, do not
chassis, before you observe the load carry loads above
commence lifting. and the area people, objects or
Leveling should where you must structures.
be checked as move the load.
often as possible • Pivoting with the
during the lifting • Never lose load must be
operation. control of your done as gently
crane with and carefully
• The cargo and the load hanging. as possible so
person that signals that the load is
should, where • Loads must held vertically
possible, be clearly always be below the
visible to you lowered with boom head and
during the entire control and be does not swing
lifting operation. put down gently uncontrolled.
on a flat surface.

210 LIGHT CRANE (TRUCK MOUNTED CRANE)

7.8.1 Not allowed!

Do not use the crane to "drag" a load.

This causes increased load on the mast and on the top, that they are not designed for,
particularly the lateral load. The crane can be damaged or may tip.

Do not use the crane to "drag" a load.

LIGHT CRANE (TRUCK MOUNTED CRANE) 211

7.9 Moving the crane at the worksite
Avoid any unnecessary movement over uneven or bumpy ground or across slopes.

If possible, avoid driving with a suspended load. If you are driving with hanging loads:

• Drive gently with • Use gentle then apply the

the "crawl gear". movements so hand brake.
that the load will
• Keep the load not swing. • Stop the crane at
as close to a stand-still before
the ground • Try to stop the lifting, lowering or
as possible. crane without using swinging the load.
the service brake,

Unpermitted angle away Unpermitted Do not drive while sloped

from the load. dragging of the load. with a hanging load.

212 LIGHT CRANE (TRUCK MOUNTED CRANE)

7.9.1 Moving a crane on a public road

Moving a crane on a public road is subject to the General Road Traffic Laws.
You must know and obey these laws in your own and others' interest. Make sure you know the
manufacturer's recommendations and your company's instructions when you prepare your crane
for moving on the road.

Make sure that:

• The crane has • Slings, lifting • Pull in all

free height. beams and wide sections.
shackles have
• The outriggers been removed and • Check your crane
are fully retracted safely stowed. a few times at
and locked. longer distances.
• The mast is Especially check
• The counterweight secured in the tires and
support jacks the trestle. air pressure.
are set, axle
locks are set, the • Check your • Mobile cranes must
transmission is machine's not be operated
in neutral and the switches and at higher speed
pivot is locked. systems (steering, than permitted by
brakes, lights, turn the rules.
• Crane hook signals, tires, horn,
is secured wipers, etc.). • Adapt your speed to
or moved. weather, road and
traffic conditions.

LIGHT CRANE (TRUCK MOUNTED CRANE) 213

7.9 Moving the crane at the worksite
7.9.2 Coordination

Building and construction work, as with any other work where mobile cranes are involved,
requires coordination on the workplace. At a construction site, regardless of size, there is a
Coordination Manager appointed. The mobile crane operator provides the coordinator with
information about the specific risks that may arise due to operations with the crane.

The Coordinator must be made aware of:

• The large forces pressure of 5 kp/ crane to overturn,

transmitted to the cm², and that the leading to the
ground when lifting crane’s maximum surface pressure as
with the crane. lift values, described above to
depending on the be exceeded.
• If the soil bearing layout, (graphs
capacity is and tables) will not • According to
suspected to be be exceeded. statistics improper
poor, special steps fastening and
are taken so that the • Overload strapping of
supporting surface jeopardizes safety cargo is the most
of the ground can and may cause the common reason of
withstand a ground occupational injuries.

You may not secure load with the crane

214 LIGHT CRANE (TRUCK MOUNTED CRANE)

7.10 Signalman
These mobile crane hand signals do not solely fulfill your job as a Signalman, as you also need
to follow these guidelines for work safety:

• Always pay • Always keep your • Prior to lifting or

attention to how hand away from setting a load, make
the crane and load your body so that sure that everyone
moves when the the operator has a is prepared.
operator follows better view and can
your signals. watch you clearly. • You can use a
middle-man to
• Prior to making the • Maintain a clear transfer signals to
lifts, you should view of the operator, the operator if it
discuss the signals the load, and the is not possible for
and the lift path entire load path. one person to see
with the operator. everything (radios
can also be used).

Crane hand signals are very The duty of the signalman is

crucial for safe and efficient to effectively communicate
crane operations at any with the crane operator
work place. Relying on hand and try to complete the job
signals means the high noise quickly as he becomes the
levels at most industrial eyes of the crane operator.
and construction sites
don’t interfere with critical There are standard crane
communication. hand signals approved by
the OSHA (Occupational
Furthermore, the human Safety & Health
hand can form a complex Administration) which
signal faster than the human are universally used and
tongue can get out even a accepted all over the world.
single syllable. Therefore,
hand signals are widely used If you are the signalman or
for faster communication the crane operator, you need
between the operator to thoroughly understand
and signalman. these crane hand signals
and apply them as needed.
When the crane operator's
visibility of the load is low The complete list of
and he is unable to see the International Crane Signals
complete path of the load are listed in the chart below.
or unable to see the landing
area, the signalman comes They will be very helpful
into the picture. during crane operations.

LIGHT CRANE (TRUCK MOUNTED CRANE) 215

7.10 Signalman
7.10.1 Hoisting Hand Signals

Explanation of the hand signals

1. Boom elevation 7. Boom elevation 12. Boom elevation

"up" "up" and holding "down" and
the load lifting the load
2. Boom elevation
"down" 8. Boom elevation 13. Lifting the load
"down"
3. Lifting the load slowly and holding 14. Lowering the load
the load
4. Lowering the 15. Swinging load in the
load slowly 9. Extending the boom indicated direction

5. Boom elevation 10. Retracting the boom 16. Stopping

slowly "up" all movements
11. Boom elevation
6. Boom elevation "up" and 17. Stop! Working
slowly "down" lowering the load movement finished

1 2 3 4

5 6 7 8

9 10 11 12

13 14 15 16 17

216 LIGHT CRANE (TRUCK MOUNTED CRANE)

7.11 Personal lift
You must not allow anyone to ride on the load or crane hook.

Passenger transport by crane has special regulations and may only be done with the consent of
your company and with the approved equipment.

Special basket for personal lifting.

You must not allow anyone to ride on the load

or crane hook.

LIGHT CRANE (TRUCK MOUNTED CRANE) 217

7.12 Locking of the crane
When the crane is not being used for short periods of time:

• Lower the load to • Apply all the brakes • Stop the engine,
the ground. and the swing lock. remove the ignition
key and lock cabs.
• Make sure you • Add palletizing for
do not obstruct wheels if you are
other jobs. in a slope.

When the crane is not being used for extended periods of time (e.g. after hours and
on weekends):

• Lower the load and unload loops.

• If space permits, turn the mast away from the working area so you do not obstruct
other operations.

• If strong winds prevail, you must be especially careful and follow the manufacturer's
recommendations and your company's instructions regarding the anchoring of the
mast and boom block.

218 LIGHT CRANE (TRUCK MOUNTED CRANE)

When you have finished studying this chapter, try to answer these questions.

1 What is the main use of a light Crane?

If you are unsure of the
answer, go back and re-read
the relevant section in the
chapter. Please note that the
questions do not cover all of
the content of the chapter.

2 When should a 3 At what job suits a 4 What part of the

Signal man be used? "Mobile Crane" best? Mobile Crane actually
lifts the goods?

5 What should the 6 What is the biggest 7 Why should you use the
operator of the Crane be risk with the use of the outriggers plates?
most attentive of? outrigger legs?

8 When should smaller 9 At what wind speed 10 How much pressure

Cranes be used? should you refrain load of the outriggers
from using a Mobile legs must the ground
Crane to lift? resist to allow use of the
Crane for lifts?

LIGHT CRANE (TRUCK MOUNTED CRANE) 219

11 How do you know what load your lifting equipment can handle?

2 What will you

12 13 What size may the 14 What are most common
do if your lifting maximum peak angle be injuries among
chain is damaged? at a loop lift? Crane operators?

15 What can happen 16 Which Protective 17 How the bending

if you turn swiftly Equipment is the most diameter impacts
with the Crane? important when you on the maximum
run the Crane? loading capacity?

18 What is the difference 19 What should you look 20 What type of Crane
between a Mobile out for when the Crane is mainly used when
Crane and a Vehicle is positioned close building tall buildings?
Mounted Crane? to a building?

220 LIGHT CRANE (TRUCK MOUNTED CRANE)

LIGHT CRANE (TRUCK MOUNTED CRANE) 221
Chapter Eight
LIGHT
FORKLIFT
8.1 Introduction

Forklifts are power trucks intended to lift or transport heavy materials.

They do this by means of steel forks inserted under the load, which is normally packaged as
pallets. For industrial and warehouse facilities, forklifts are indispensable equipment essential
to operations.

224 Light Forklift

8.2 Basic Components of a Forklift

2 5

3
6

18 7

17

15 9

16
10

11
12
14

13

1. Lift chain 7. Operator’s seat 13. Driving wheels

2. Mast 8. Counterbalance 14. Tilt cylinder

weight
3. Head lamp 15. Fork carriage
9. Engine hood
4. Overhead guard 16. Forks
10. Fuel tank
5. Rear view mirror 17. Load backrest
11. Steering wheels
6. Handrail 18. Lift cylinder
12. Foot rest

Light Forklift 225

8.3 Operator’s Environment
8.3.1 Controls &Instrument panel

1. Ignition switch 5. Parking Brake 11. Four Wheel

Light (Red) Drive Switch
2. High
Transmission 6. Engine Preheat 12. Front and Rear
Temperature Light (Red) Work Lights
Light (Red)
7. Engine Water 13. Warning
3. Low Temperature Light Switch
Transmission Gauge
Oil pressure 14. Turn
Light (Red) 8. Hour Signal Switch
Meter Gauge
4. Low Engine 15. 12 Volt
Oil Pressure 9. Voltmeter Gauge Power Source
Light (Red)
10. Fuel Gauge

8 10 3 2 5 4 11 12

Trans Park
Temp Brake
On Front

HOUR METER 4WD Light

Trans Engine oil
000000 Pressure Pressure Off Front
Rear

FUEL
Left Right
Preheat

On

Stop
Off

Run
12v Start

VOLTS TEMP

9 7 6 15 13 14 1

226 Light Forklift

8.4 Operating Controls
Description

1. Lowering / 3. Tilt forward / 5. Rotate ccw

raising lever backward lever / cw lever

2. Extending / 4. Shift left / 6. Lower / raise

retracting lever right lever stabilizers lever

7. Hand throttle

7
1 3 4 5

2 6

Light Forklift 227

8.5 Operator’s Restraints
Operator restraints will hold you in the seat if you strike an object or if the forklift overturns.
Failure to wear a seat belt can also result in the operator being thrown outside the protective
cage in the event of an overturn.

If your forklift has a restraint such as a seat belt or a lap bar, you must use it.

Forklift Accident

228 Light Forklift

8.5.1 Seatbelts 8.5.2 If the forklift
overturns!

Seatbelts are provided on most forklifts and should be worn. If your forklift
Seatbelts help to: begins to overturn:

• Stop the operator from being thrown out of the seat • Stay in the seat
if the forklift is involved in a collision.
• Hold on firmly
• Keep the operator's body within the confines of the
overhead guard. • Lean into the
opposite direction
• Prevent the operator from being thrown of the fall, rather
out of the forklift and crushed if the forklift than trying to jump
becomes unstable. from the forklift.

When a forklift is not fitted with a seatbelt the forklift owner Many fatal accidents occur
should consider fitting a seatbelt. The seatbelt should be fitted happened when the operator
in accordance with the forklift manufacturer's instructions. tries tried to jump from
the forklift.

Light Forklift 229

8.6 Preparation
8.6.1 Forklift Pre-Use Checklist

• Wear a hard hat 8.6.1.1 External Inspection

as protection
against falling
objects or from a • Look at the prevent them from
tip over. bodywork of the coming loose.
forklift to see
• Wear a seat belt. if there is any • Inspect all tires,
damage, and ensure making sure that
• Before climbing that all moving they are not worn
into the cab, parts are lubricated. or damaged in any
check the Inspect the floor way, and tighten all
position of the beneath the forklift wheel nuts. Check
steering wheels. for evidence of the tire pressure
any leaks from to ensure that they
• Release the the engine. are inflated to the
parking brake. Tighten all bolts to correct levels.

• Follow the
manufacturer’s 8.6.1.2 Internal Inspection
instructions
for engaging
the machine. • Check to see if the horn and alarms work, as these
are important tools in ensuring other people are
• Only operate aware of your presence. Inspect all instruments
the forklift that inside the machine to be sure that they are well
you are licensed maintained and working correctly. If there are any
to operate. warning lights displayed on the dashboard of the
machine, consult the machine's handbook for
• Do not operate instructions on how to rectify the problem. Inspect
the forklift with the seat belt to ensure that it is not damaged.
wet or greasy
hands or feet. • Press on each of the pedals. A "spongy" feel
indicates that the hydraulic fluid levels are low, or
that there is a leak.

Wear a
hard hat as
protection
against
falling objects.

230 Light Forklift

8.6.1.3 Other
Inspection Items
1. General condition
Check all engine fluid levels, and cleanliness. free travel).
whether it is oil, brake fluid
or water. Inspect the battery, 2. Engine oil level, 9. Parking brake
checking for any damage or fuel level, radiator should hold
corrosion. At all times during water level. against slight
the inspection wear protective acceleration.
clothing such as gloves and 3. Check the
goggles to prevent contact condition of the 10. Dash control
with any harmful substances. tires, check for panel lights and
wear, damage gauges should be
and air pressure if operational.
8.6.1.4 Record pneumatic.
Your Inspection 11. Check the
4. Check that the seat brake.
Fill out your checklist battery is fully
completely, and sign it to charged, check 12. Check that the
prove that you are satisfied cables for clutch disengages
that the forklift is in good exposed wires; the transmission.
working order. Health and check that the
safety officers will be asking battery connection 13. Check forks if bent.
to see evidence that you had is not lose.
inspected the machine in 14. Check lift chains
the case of any accidents, 5. Check that the for equal tension,
damage or other incidents. horn functions, broken pins
loud enough to be and wear.
heard in a working
8.6.1.5 Pre- environment. 15. Hoses if held,
Operation Checklist securely - not
6. Check that the lose, curled, worn
Safety inspection must backup lights, or rubbed.
be carried out once per head lights and
day or per-shift. If a defect all the lights are 16. Check the hydraulic
affecting the safe operation operational. controls-lift and
of a forklift is detected, the tilt levers.
forklift must immediately be 7. Check the steering
taken out of service and is mechanism 17. Listen for any
not to be used until the fault with the unusual sound
is rectified. engine running. or noises.

Check all
8. Check the foot 18. Fire extinguisher
brakes (not more should be present

engine
than 10 mm of and charged.

fluid levels.

Light Forklift 231

8.7 Starting the engine

• Make sure the • Turn ignition switch lights and

parking brake is on. to start position gauges to ensure
then release to everything is
• Safety belt Run position when operating correctly.
is fastened engine is running.
and secure. • Engine temperature
• (NOTE: Max crank must be above
• FNR switch is in time = 15 seconds) 160 o F before
neutral position operation.
and gear shift lever
is in neutral. • Observe indicator

8.7.1 The Machine 8.7.2 How do forklifts safely carry and lift
Operation heavy loads?

Operating a forklift is A forklift has two forks that are located on the front of the
different than driving a car. machine. These two forks only move up and down, but they
can also tilt upwards and downwards. The operator controls
In a car the front wheels the movements of the forks by using a hydraulic system. The
steer the vehicle. However, hydraulic system applies pressure to a bar with rolling chains
a forklift has the steering that is located in the forklift, known as “MAST”.
wheels in the rear. The rear
end of the forklift swings 8.7.3 Forklift Safety Features
in a circle around the
front wheels. Backrest extensions on the forks prevent part of the load from
falling rearward towards the mast, damaging its mechanism or
The operator must check injuring the operator. This is required when loads are lifted high
that there is room for the and have the potential to fall – usually under conditions such
rear end to swing when as acceleration, sudden stops or driving on an uneven surface.
making turns.

Observe indicator lights and

gauges to ensure everything
is operating correctly.

232 Light Forklift

8.8 Safe Operation
8.8.1 Center of Gravity and Load

• The fork lift has moving parts and • The center of gravity moves up
has a center of gravity that moves. and down as the upright moves
up and down.
• The center of gravity moves forward
and backward as the upright is tilted • The load center is determined by
forward and backward. the location of the center of gravity
of the load.

8.8.2 How the weight

is divided on
the forklift?

Example of calculation

• Forklift weight
15,000 kg

• Payload
10,000 kg

• Total Weight
= 25,00 kg

• Rear axle press

2,500 kg

• Front axle press

22,500 kg

Weight distribution 10% 90%

front and rear.

Light Forklift 233

8.9 Stability Triangle
The stability triangle has one Stability Triangle
point in the center of each • The load is
drive wheel and one point at carried on the
the pivot point, or center of tips of the forks.
the steering wheel axle.
• The load is
As the mast is tilted forward, tilted forward.
the center of gravity moves
forward, closer to the lines • The forklift
of the stability triangle. As movement
the mast is tilted backward, causes the
the center of gravity moves center of gravity
backwards. If the center to change.
of gravity crosses over the
stability triangle lines, the
forklift will tilt and possibly The center of gravity of the forklift-load combination can
possible fall over. move outside the stability triangle if:

Machine becomes unstable when load is

raised because center of gravity shifts away

Loaded forklift center of gravity

Unloaded forklift center of gravity

234 Light Forklift

8.10 Moving on Slopes
Moving with a load downhill Moving direction on slopes.
can result in loss of the
load and the control of the
forklift. If you move a forklift
on an incline, you must keep
the load on the uphill side.
Otherwise, you may have
no weight on the steering
wheels that steer and can
lose control of the forklift.
The load may could also fall
off or cause the forklift to tip.
Responsibilities of forklift
operators: Individuals related
to forklift operation.

The operator must pay

attention to the effect
of centrifugal force and Kinetic force
kinetic energy on
the machine

CENTRIFUGAL
FORCE

DIRECTION
OF TRAVEL

Moving with a
load downhill
can result in
loss of the
load and the
control of
the forklift.

Light Forklift 235

8.11 Machine Requirements
Operators must be aware of the following points:

• The weight of • The height at • The blind-spots

the load and the which a load must or individuals
forklift capacity. be lifted. who might be
sharing the work
• The stability • Obstacles both space with the
of the load. in the path and forklift operator.
overhead, where
the forklift operator
is operating.

236 Light Forklift

8.12 Operating Forklift in different working sites
When you work in a terminal Forklifts are often involved If there are specific particular
area as a Forklift Operator, in work place accidents. forklifts Lanes, you are
the traffic situation is More than half of all forklift obliged to use them!
different; there are often accidents occur when
other motorists than if you vehicles are moving. Always use the designated
were indoors in tight spaces. forklift lanes.
Be aware of other
traffic around you.

Always be sure to have a

clear view. It is difficult to
see what is in front of the
forklift due to the presence
because of the load.

Take caution and do

not operate outside the
loading ramp.

Forklifts
are often
involved
in work
place
accidents.

Light Forklift 237

8.12 Operating Forklift in different working sites
If the load obstructs your There is the also a risk of overturning with the forklift,
forward vision, you must especially when operating on sloped surfaces or on loading
move backwards instead. docks and similar places Be aware of how the center of gravity
Many times the view when is shifting when you lift a load.
reversing is better than
when driving forward. The center of gravity is moved forward when carrying
heavy loads.

Remember that the forklift

turns with its rear wheels;
this means that many
potentially hazardous
situations may arise to
people in the forklift's
proximity, in that they can
become trapped, especially
if they are in hidden angles.

Seek assistance if you

cannot see properly in
front of you.

The forklift is often

The center of gravity is

used in temporary
construction areas.

Be extra careful when moved forward when carrying

heavy loads.
operating in areas used
by the public.

238 Light Forklift

8.13 Accidents

1. Accidents and incidents should be reported to the site management immediately.

2. Take the necessary action to reduce the effect of damage, especially

personal injuries.

3. Explain the incident/accident to the site manager. Wait for further instructions from
the site management.

Accidents and incidents should be reported

to the site management immediately.

Light Forklift 239

8.14 Safety during Operation

• Be cautious when • Lift the load to • Always be aware

moving forklifts up a height to clear when sharing
or down slopes, stacks and then work space with
whether or not you lower to a position pedestrians. Be
are carrying a load. which gives both aware of their
maximal stability surroundings,
• Engage forks and clearance of especially
completely when obstacles. where visibility
picking up a load. is impaired.

8.14.1 Forklift, Operator 8.14.2 Precautions

and Load Safety

• Cages offer • Be aware of • Move materials

protection. obstacles, only in the
both ahead designated
• Inspect all and overhead. areas with
items before adequate space.
moving a load. • Be cautious of
about cable trays. • Do not block
• Check pallets individuals
and remove any into a stack.
loose items.

• Wear a helmet Additional Precautions

for additional
protection.
• Make sure horn works well.
• Make sure all the
loads are secure. • Be cautious when backing up.

• Lower • If you cannot see well, get a spotter.

loads to move.
• Loads should be lowered for stability and to have a
clear vision.

Note: Electrical power When needed, have a spotter who has a full 360 degrees’ view.
lines are the leading When moving in in the forward direction. Lowering and tilting
cause of death in the load back towards the forklift frame increases stability as
forklift operations. well as operator’s visibility.

Lift the load to a height to clear stacks.

240 Light Forklift

8.15 Signal man

RAISE THE TINES. With LOWER THE TINES. With arm MILT MAST BACK. With
forearm vertical, forefinger extended, palm down, lower forearm vertical, thumb
pointing up, move hand in arm vertically. extended, jerk thumb over
small horizontal circle. shoulder.

MILT MAST FORWARD. With MOVE TINES IN DIRECTION DOG EVERYTHING. Clasp
arm extended, thumb down, FINGER POINTS. With arm hands in front of body.
lower arm vertically. extended, palm down, point
forefinger in direction of
movement.

STOP. Extend both arms, palms down.

Light Forklift 241

8.16 Load Capacities

• Be aware of
load centers.

• Be aware of the
total capacity.

• Do not exceed
load center.

• Be aware that
fork extenders
make the load
less stable.

Most tipping accidents

occur because of the
above problems.

8.16.1 Picking
up the Load

• Center forks on
the load.

• Approach slowly
to about 0.5m
from the load.

• Engage forks
completely.

• Lift forks until the

load is engaged.

• Tilt mast back.

• Clear stacks by
slowly backing
away from them.

• Lower forks
for travel.

242 Light Forklift

8.17 Load Stability

• Tilting the load higher the load, the Do not exceed the
forward reduces less the stability load center.
the load stability there is.
and can cause • Be aware that fork
damage to • Adjust the fork extenders make the
the forks. extension to load less stable.
maximum for
• Check the vertical the load. • Know the capacity
load backrest. The of the forklift.

8.17.1 Key Risks to Forklift Stability

• Some key factors • A forklift

related to forklift may become
stability: ‘dangerously’
unstable when
• Most rollovers driving with a raised
involve unloaded load or a raised
forklifts, because empty load carriage.
unloaded forklifts
are less stable than • Loads attached
a loaded forklift to a forklift, or
with the load being suspended from a
carried low. jib attachment, are
more likely to result
• When operators in a full forward tip
apply the brakes over when braking.
on a loaded forklift
they easily lose • Forklifts can easily
stability. overturn if they
make contact
• Uneven flooring, with overhead
particularly with a structures.
height difference
in excess of • Lift capacity and
40mm across the vertical lift travel,
front wheels, can are the two most
seriously impact on important things
a forklift’s stability
when carrying • To look for in order
its rated load at to prevent forklift
full height. instability incidents.

Light Forklift 243

8.18 Managing Rollover Risk for Forklift Operators
Fatality may occur if the operator jumps or is thrown from an overturning forklift.

When a forklift overturns, the safest place for the operator to be in is in the cabin with a seatbelt
on. The operator is advised to hold on firmly, and lean in the opposite direction of the overturn.
While seatbelts may be an inconvenience, they may save the operators life.

8.18.1 Stacking

• Take precautions
when loading
or pulling
from a stack.

• Do not stack
materials
too high.

• Make sure the

area is clear of
personnel.

8.18.2 Operating a Forklift safely

• Never move
the forklift Fork
Lift when you
cannot see.

• Be aware
of overhead
obstructions.

• Never travel
with a load in a
raised position.

• Make gradual
accelerations and
decelerations.

• Do not exceed the

Make gradual accelerations

speed to more
than 8 to 9 km/h.

and decelerations.

244 Light Forklift

8.18.3 Setting down a load

Mechanical conditions/ or design features that increase the

• Never travel risk of for forklift accidents:
up towards a
person standing
at a stack. • Malfunction of brakes.

• Do not block exits. • Malfunction of steering.

• Tilt mast forward • Malfunction of clutch, shift linkage, or transmission.

to the vertical.
• Malfunction of mast assembly.
• Set the load down
or on a stack. • Leaks in the hydraulic systems or transmission.
Lower the forks.
• Safety devices lacking, inadequate, or
• Look back malfunctioning.
and then clear
the stacks. • Emissions from forklifts.

• Blind spots or obstructions blocking operator's view.

Other Safety Notes

• Never go more
than 10 meters
away from an
unattended
forklift.

• When finished,
always ground
the forks.

• When starting,
always raise forks
before moving.

• If in doubt about
anything, ASK!

• No one
should ever walk

• Near or
under a load.

Light Forklift 245

8.19 Speed Limit and Braking Distance
8.19.1 Speed limit: 8.19.2 Braking Distance

• Forklift brakes could • The speed at which

• Always travel at still cause a tip-over a forklift can stop
a speed which or loss of load when in an emergency is
can be easily applied heavily in determined by the
controlled. The an emergency, even speed at which it was
forklift cannot though they are traveling, the weight
be stopped less powerful than of its load and the
immediately. other vehicles. road surface.

• Workplaces rely on • The emergency

• It takes about the operator to apply stopping distance
0.4m meters for just the right amount of a fully loaded
each km/h for a of brakes to quickly forklift is often
panic stop. stop without causing significantly
it to tip over. The underestimated
operator comes to when planning for
• It takes 1 to awareness only when pedestrian safety.
1.5 seconds to the back wheels come
become aware off the ground. This is Researches shows
of the hazard unacceptable. that a loaded forklift
and another full cannot use its
second for the • Speed limits should maximum braking
mechanical parts be prominently capacity as the load
of the machine displayed, observed will slide or fall off
to respond. and enforced. Signs from the forks, or
must be easily seen by the forklift will tip
operators. over forwards.

8.19.3 Minimum Actual Emergency Stopping Distance

The below chart depicts accident research centers findings on emergency braking distances, for
typical forklifts on a level surface, based on an operator reaction time of 1.5 seconds.

Speed(km/h) 6 12 14 16 18 20 22

Speed in meters per second 1.7 3.3 3.9 4.4 5 5.6 6.1

Distance travelled while operator

2.5 5 5.8 6.7 7.5 8.3 9.2
reacts to emergency (m)

Minimum theoretical emergency

2.8 6 7 8.5 9.5 11 12.5
stopping distance (M)

Minimum Actual Emergency

3.2-2.9 8-7 10-8 12-9.5 14-11 16.5-13 19-14.5
Stopping Distance – test results (m)

246 Light Forklift

8.20 Duties of self-employed persons
Self-employed persons operating forklifts must take all reasonably practicable steps to ensure
their work does not endanger themselves or others.

They are expected to cooperate with anyone who has a duty under the legislation and to know
and comply with the legislation.

8.20.1 Duties of 8.20.2 Abilities, Duties and Qualifications of

supervisors the Operator

Supervisors are expected to: Abilities:

A good start to operating a forklift beginning is having the mental
and physical abilities to operate the Forklift safely. Having:
• Know the job.

• Understand • Conscious • Knowing where

how to awareness to go to get more
control hazards. information
• Demonstrated
• Ensure that their skill • Prior training
workers know
and comply • Hazard recognition • Tested
with safe work
practices and • Knowledge of safe • Solid, Safety safe
legislation. principles experience

• Supervise
workers Duties of the Operator:
effectively.

• Set an example • Make pre-operation to others. Make it a

by working and safety inspection. positive one.
acting safely.
• Pick up, move and set • Use the training,
down the load according instruction and personal
to the laws of physics protective equipment
related to moving the provided by the

Supervisors
with load. employer.

are expected
• Make safety a part • Work and act safely.
of every action you

to set an
perform. • Follow the health and
safety rules and work

example by
• Traveling throughout the procedures established
site, your actions and by the employer.

working and
commitment towards
safety are highly visible • Know and comply with

acting safely.
and send a message the legislation.

Light Forklift 247

8.20 Duties of self-employed persons
Qualification: 8.20.3 Duties of Employers

Employers can accomplish this by:

• Have a valid
Operator's
License for • Establishing forklift • Determining the
the state, and selection criteria. competency of
have a good operators.
operating record. • Providing safe
forklifts. • Ensuring that
• Must be workers are
physically • Preparing rules adequately trained.
capable of for inspecting,
operating the testing, operating • Providing
forklift for long and maintaining competent
periods of time. equipment. supervision.

• Must be able to
judge distances
and heights
accurately, and
have good hand-
eye coordination.

• Must be capable
of looking over
his/her shoulder
when traveling
in reverse.

• More importantly,
the operator
must be mentally
alert at all times.

• If the operator
is required to
perform some
physical handling
of materials, he
must be physically
capable of
handling such
materials without
putting undue
stress on the back.

248 Light Forklift

8.21 Health Management during operation
8.21.1 Poorly Ventilated Workplaces

Forklifts powered by internal combustion engines should not be used in an enclosed space.

Electrically powered forklifts are the safer alternative.

Slips, Trips and Falls

To manage risks related to slips, trips and falls, it is essential to purchase or refit forklifts so that
each forklift has:

• Steps that give a

good footing

• Anti-slip surfaces
and grab handles

• To provide three
points of contact
(hands & feet)
while mounting
or dismounting
the forklift.

• Ensure that
uneven surfaces
are removed or
minimized.

• Ensure forklift
operating and
parking areas are
well lit and clear
of obstructions.

• Redesign
work practices
to minimize
the need for
operators to
get on and off
the forklift.

• Operator should
never jump to
get down from
the forklift.
Too much carbon monoxide could be the reason.

Light Forklift 249

8.22 Precautions & dangers
The following precautions are suggested to help prevent accidents. A careful operator is the
best operator.

Most accidents can be avoided by observing certain precautions.

Read and take the following precautions before operating a this forklift. Forklift Equipment
should be operated only by those who are responsible and instructed to do so.

1. Study the under pressure. 9. Never tilt forks

Operator's Manual DO NOT use your forward while
thoroughly, and hand to check transporting loads.
be completely for leaks. Use a This could cause
knowledgeable piece of cardboard the machine to tip
about the or paper. over. Keep the load
operations of the tilted backward
equipment. 6. IF Fluid is injected and as close
into skin, obtain to the ground
2. Please pay close medical attention as possible.
attention to safety immediately.
warnings posted in 10. Watch for low
various areas of the 7. Always start the clearances such
operation section. engine while sitting as power lines
in the operator's when operating
3. Be careful of other seat. Shut off equipment.
people in your equipment before Electrocution
vicinity. ALLOW dismounting from could occur as a
NO RIDERS. the machine. result of contact.

8. TURN THE MAIN 11. NEVER allow

4. DO NOT stand on, SWITCH OFF children or anyone
or under, the forks before performing not properly
for any reason. any service or trained to operate
maintenance. equipment.
5. Hydraulic fluid is

Always start the engine while sitting in the

operator's seat.
Shut off equipment before dismounting
from the machine.

250 Light Forklift

8.23 Forklift Maintenance
Checklist: Fork Lifts

Operator/Inspector Date Time

What are you inspecting? What are you looking for? Evaluator Comments

Fuel Leaks, Level

Hydraulic Oil Leaks, Level
Engine Oil Leaks, Level
Radiator Coolant Leaks, Level
Transmission Fluid Leaks, Level
Tires Condition and Pressure
Forks, Top Clip Retaining Pin and Heel Check Condition
Hydraulic Hoses, Mast Chains, Cables and Stops Visual Check, Leaks, Damage
Overhead Guard Attached, Damage
Attached, Visible, Legible (Refer to Parts
Safety Warnings
Manual for Location)
Battery Check Water/Electrolyte Level and Charge
All Engine Belts Cracked, Damage, Rips, Visual Check
Squeeze Rubber Dirt Trap or Check the
Engine Air Cleaner
Restriction Alarm (if equipped)
Fuel Sedimentor (Diesel) Condition
Operator’s Manual In Cab
Attached and Information Matches
Nameplate
Model, Serial Number and Attachments
Condition, Torn, Ripped,
Seat Belt, Buckle, Retractor
Damage to housing
Hood Latch Adjusted and Securely Fastened
Brake Fluid Leaks, Level
With Engine ON
Accelerator or Direction Control Pedal Functioning Smoothly and Properly
Service Brake Functioning Smoothly and Properly
Parking Brake Functioning Smoothly and Properly
Steering Operation Functioning Smoothly and Properly
Drive Control – Forward/Reverse Functioning Smoothly and Properly
Tilt Control – Forward and Back Functioning Smoothly and Properly
Hoist and Lowering Control Functioning Smoothly and Properly
Attachment Control Operation
Horn and Lights Functioning Properly
Cab (if equipped) – Heater, Defroster, Wipers Functioning Properly
Gauges: Ammeter, Engine Oil Pressure, Hour
Meter, Fuel Level, Temperature, Instrument
Functioning Properly
Monitors

For more information, please refer to the Operation and Maintenance Manual or any other applicable manuals and instructions for this
product. If you have questions, please contact your local Caterpillar dealer.

Light Forklift 251

8.23 Forklift Maintenance
8.23.1 Precaution before maintenance

• Do not conduct block support. counter

do repairs in weighting
an area with • To prevent the shall not be
a potentially forklift from performed
flammable or accidentally unless
combustible being started; approved by the
atmosphere. remove and manufacturer.
keep control
• Make sure there of the key or • Forklifts in need
is adequate disconnect the of repairs to
ventilation battery while the electrical
to prevent making repairs. system must
accumulation If the electrical have the battery
of exhaust or system will disconnected
gas fumes. be serviced, prior to the
you must repair work.
• Do not use disconnect the
flammable battery before • If the
solvents to clean starting repairs. temperature
a forklift. Use a of any part of
non-combustible • Forklifts should the forklift is
solvent. not be altered so found to be
that the relative in excess of
• Never go positions of the normal operating
under a forklift various parts are temperature, the
supported only different from lift should be
by a jack or what they were removed from
under any part when originally service until the
supported only received overheating has
by hydraulic from the been eliminated.
pressure! Install manufacturer.
jack stands
or a secure Additional

Make sure there is adequate ventilation.

Forklifts in need of repairs to the electrical

system must have the battery disconnected
prior to the repair work.

252 Light Forklift

8.24 Shut down procedures

• Return your
forklift to the
proper area.

• Put the
directional lever
in neutral.

• Set the
parking brake.

• Completely lower
the forks.

• Put the
mast in full
vertical position.

• Turn off
the forklift.

• Take the key and

return it to its
proper place.

Your forklift is your responsibility until it is returned to its place at the end of your shift.

Light Forklift 253

When you have finished studying this chapter, try to answer these questions.

1 You will be asked to carry a load, but it´s too heavy for the
If you are unsure of the forklift. What will you do?
answer, go back and re-read
the relevant section in the
chapter. Please note that the
questions do not cover all of
the content of the chapter.

2 When affect the 3 How high above the 4 You have cargo which
centrifugal force floor must the cargo be blocks the view. What
you’re driving? during transport? are you doing?

5 Who is primarily 6 Where is the common 7 Where are the forklift’s

responsible for the center of gravity for a stability triangle points?
forklifts condition forklift without load?
(daily inspection)?

8 How can you most 9 What type of injury 10 What should you
easily be testing the are the most common do if the forklift has
brake on a forklift? accidents with forklifts? leaked oil during the
night parking?

254 Light Forklift

11 Are you allowed having passengers in the forklift?

2 What should you

12 13 What are the most 14 Why you should not
do when you park important standard drive with load high?
the forklift? hand signals for
the forklift?

15 How much are the safe 16 What is the average 17 What is the correct
speed limits to drive the reaction time for position of the mast
forklift safely? forklift operator? when you park
the forklift?

18 What are the 19 Why Tilting the mast 20 What is the function of
responsibilities of forward with a high the load backrest?
forklift operators before load is considered as a
starting the operation? dangerous action?

Light Forklift 255

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