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– Game Ranging / Field Guiding Course
This course material is the copyrighted intellectual property of WildlifeCampus. It may not be copied,
distributed or reproduced in any format whatsoever without the express written permission of WildlifeCampus
All these parts are mounted on a steel frame called a chassis and surrounded by
bodywork.
It is very important that every field guide is very familiar with all aspects of the vehicle under his / her care. There will come a time when you will be
required to repair the vehicle in the bush.
Your practical training will teach you the rudimentary points of vehicle repair and
maintenance.
– Game Ranging / Field Guiding Course
This course material is the copyrighted intellectual property of WildlifeCampus. It may not be copied,
distributed or reproduced in any format whatsoever without the express written permission of WildlifeCampus
Supplies electricity to the ignition system and other electrical components.
Made up of 6 cells each cell producing 2 volts of electricity, making a total of
12 volts.
Each cell has 2 sets of plates called electrodes. One electrode is made of lead dioxide, the other of spongy lead.
Electrodes sit in a solution of dilute sulphuric acid called the electrolyte.
Acid reacts with the electrodes, creating electrical energy from chemical
energy.
As chemical reaction continues, lead sulphate builds up on the electrodes and the acid turns to water. When the plates are covered in lead sulphate, the
battery is flat.
Re-charging the battery with an electric current restores the electrodes to their original state.
Heaviest demand is made on the battery when engine is started.
Most batteries are earthed by means of the negative terminal being attached
to the chassis or bodywork of the vehicle.
The Coil
The car battery produces 12 volts.
Thousands of times more voltage is needed to produce sparks in the spark
plugs.
Purpose of the coil is to convert 12 volts to as much as 60 000 volts.
This is accomplished by means of a complex system of wiring around a central
soft iron core within the coil.
This high voltage is then sent to the distributor.
The Distributor
Is the link between the electrical components and the engine itself?
Distributes the coil’s high voltage to the spark plugs in a specific order by means
of a rotor arm.
Consists of a body and a cap.
The cap has five terminals, a central one carrying power from the coil, which is connected to the centre of the rotor arm, and 4 outer terminals which lead to
the spark plugs.
Power from the coil enters the distributor at the central terminal.
As the rotor arm turns, it connects the central terminal to the spark plug
terminals in rotation.
In this way, the electrical current is “distributed” to the various spark plugs.
The body of the distributor contains the contact breaker “points” and the
condenser.
Purpose of the “points” is to interrupt the flow of electricity through the system
which is necessary for high voltages to be attained.
The condenser prevents excessive arcing from taking place.
– Game Ranging / Field Guiding Course
This course material is the copyrighted intellectual property of WildlifeCampus. It may not be copied,
distributed or reproduced in any format whatsoever without the express written permission of WildlifeCampus
Produce the sparks needed to ignite the petrol/air mixture in the engine’s
cylinders.
Consist of central electrode passing through centre of insulator with another
earthed electrode on the outer edge of the bottom of the plug.
The 2 electrodes are separated by a small gap.
High voltage electricity runs down the central electrode and jumps across this
gap in the form of a spark.
The spark must be big enough to light the petrol/air mixture efficiently, which
means that the gap must be larger. The larger the gap, the more voltage
required.
The gap measures 0,6 - 0,8mm.
The electrodes erode and deposits build up as time goes by and the gap must therefore be checked regularly.
Factors that can cause erratic sparking include: crack in insulator, film of oil or
water on outer surface, defective plug wire or connection.
The Ignition Switch
By turning the ignition switch using a key, a connection is made between the
battery and the rest of the electrical system.
This starts the flow of electricity through the system.
The Starter
Starter motor turns the engine over until it fires.
Engines must turn at 250-300 rpm to start.
This needs large amount of electrical power and therefore drains more electricity from the battery than any other component.
Because of this high current, the starter needs a heavy-duty switch to connect
it to the battery.
This switch is called a solenoid and is controlled by the ignition switch.
Starter is connected to engine crank-shaft by a pair of gears, one small one on the starter motor called a pinion, and a larger one called a flywheel which is
directly connected to the crank-shaft.
When the ignition switch is turned, the pinion engages with the flywheel, the starter motor rotates, so rotating the fly-wheel which in turn rotates the crank-
shaft.
As soon as the engine fires, the pinion disengages from the flywheel, to prevent damage to the starter motor.
– Game Ranging / Field Guiding Course
This course material is the copyrighted intellectual property of WildlifeCampus. It may not be copied,
distributed or reproduced in any format whatsoever without the express written permission of WildlifeCampus
Generates electricity whilst the engine is running, so keeping the battery fully-
charged.
Is connected to the drive-shaft of the engine by means of a fan-belt.
Power from the engine is transferred to the alternator by means of the fan-belt, which then spins the alternator, so allowing it to generate current.
This current then re-charges the battery.
Instrumentation
The main instruments on the dashboard to note are the charge warning light,
oil pressure warning light, fuel gauge and temperature gauge.
The charge warning light lights up if the alternator isn’t charging the battery. This could be because of a faulty alternator or a loose or broken fan-belt.
Oil pressure warning light lights up if oil pressure or level is too low.
Fuel gauge monitors the amount of fuel in the tank.
Temperature gauge monitors the engine temperature. If gauge indicates
“high”, then overheating is taking place. This could be because of low coolant level in the radiator or a loose fan-belt.
– Game Ranging / Field Guiding Course
This course material is the copyrighted intellectual property of WildlifeCampus. It may not be copied,
distributed or reproduced in any format whatsoever without the express written permission of WildlifeCampus
Brakes slow the car down by causing friction between a non-moving part of the
vehicle and a drum or disc which turns with the wheel.
The braking system consists of a fluid reservoir attached to a master cylinder containing a piston, which in turn is connected to a series of pipes leading to
brake cylinders at each wheel.
When pressure is applied to the brake pedal, the piston in the master cylinder forces the hydraulic fluid in the system through the brake pipes under pressure
to the wheel cylinders, where a pair of pistons are then forced outward.
These pistons then force the brake pads on the inside of the drum outwards so
that they meet the drum. This friction then causes movement of the drum to
slow.
The brake fluid reservoir must be checked on a regular basis to ensure that
there is sufficient fluid.
– Game Ranging / Field Guiding Course
This course material is the copyrighted intellectual property of WildlifeCampus. It may not be copied,
distributed or reproduced in any format whatsoever without the express written permission of WildlifeCampus
Consists of steering wheel, steering column with universal joints, either a rack
and pinion steering gear, or a steering box, and ball joints next to the wheels.
The steering box and the system of gears and linkages that connect the steering wheel to the front wheel are designed to give the driver directional control with
the minimum of effort.
The steering gearbox converts the turning motion of the steering wheel into a to-and-fro movement of the steering linkages.
– Game Ranging / Field Guiding Course
This course material is the copyrighted intellectual property of WildlifeCampus. It may not be copied,
distributed or reproduced in any format whatsoever without the express written permission of WildlifeCampus