Starter Motor!

Starter motor

A starter is an electric motor that turns over or "cranks" the engine to start it.
A starter consists of the very powerful DC electric motor and the starter solenoid that is usually attached to the motor (see the picture). Inside, a typical starter motor has the electric windings (coils) attached to the starter motor housing and the armature (the rotating part) that is connected through the carbon brushes in series with the windings. On the front end of the armature, there is a small gear that attached to the armature through an overrunning clutch. This part is commonly known as the Bendix.

Starter solenoid

The starter solenoid works as a powerful electric relay - when activated, it closes the electric circuit and sends the battery power to the starter motor. At the same, the starter solenoid pushes the starter gear forward to mesh with the engine's flywheel. A typical starter solenoid has one small connector for the control wire (the white connector in the photo) and two large terminals: one for the positive battery cable and the other for the starter motor.

Battery cables

A starter motor requires a very high current to crank the engine, that's why it's connected to the battery with thick (large gauge) cables (see the diagram). The negative (ground) cable connects the "-" battery terminal to the engine cylinder block close to the starter. The positive cable connects the "+" battery terminal to the starter solenoid.

How a starting system works:

When you turn the ignition key to the Start position, the battery voltage goes through the starter control circuit and activates the starter solenoid, which in turn energizes the starter motor. At the same time, the starter solenoid pushes the starter gear forward to mesh it with the engine flywheel. The flywheel is attached to the engine crankshaft. The starter motor spins, turning the engine crankshaft allowing the engine to start.

Neutral safety switch

For safety reasons, the starter motor can only be operated when the automatic transmission is in Park or Neutral position; or if the car has a manual transmission, when the clutch pedal is depressed.
To accomplish this, there is a Neutral Safety Switch installed at the automatic transmission shifter mechanism or at the clutch pedal in case of a manual transmission. Often a transmission range sensor - the part that tells the powertrain computer which position (P R N D) the transmission is in, is used as a neutral safety switch (in the photo).
When the automatic transmission is not in Park or Neutral (or when the clutch pedal is not depressed), the neutral safety switch is open and the starter control circuit is disconnected.

FUEL!

Theory and background-

Procedure for Experiment-

Reflection on experiment-

                                                               [Do you know how to change a fuel pump?]

http://www.youtube.com/watch?v=1FcJF7HaRlE  
 ^^^ WATCH!! HOW TO CHANGE A FUEL PUMP!!

Fuel Injection

Fuel Pump

*Multi-port injection is still widely in use today. So far it's the most efficient method of metering gas into the engine. Multi-port fuel injection, also known as MFI, consists of an injector for each cylinder in the engine. This injector sprays fuel directly through the intake valve or valves into the combustion chamber. Each injector is activated separately by wire. Early versions of this system, such as CIS, Jetronic and Motronic utilized a fuel distributor that metered fuel to the injectors through separate fuel lines. Later versions utilize a single fuel line that connects to a fuel rail on top of the engine. The injectors take gas from the central fuel rail and squirt it into the engine when told to do so.

*A fuel pump is used to supply fuel to the fuel injection system or carburetor, depending on the year of the vehicle. Older vehicles use a mechanical pump to deliver low pressure fuel to the carburetor, while fuel injected vehicles require an electric pump capable of the high pressures required to make the system work efficiently. A fuel injection system is more efficient than its predecessor the carburetor and can better operate in extreme conditions, while becoming more dependable at start up.





Fuel Safety.
Extreme care should be taken when working with any component of the automotive fuel
system. Petrol is a very volatile and inflammable substance.
- Never expose petrol to a naked flame, spark, or heat.
- Always disconnect the negative terminal of the battery before performing any task that
would release petrol from any part of the system.
- Always use a container to catch any dripping petrol.
- Wipe petrol spills away immediately no matter how minor.
- When extra lighting is required always use a flash light rather than a lead light. Petrol
spilt onto a hot bulb may cause the bulb to explode and ignite the fuel.
- Never attempt to weld a petrol tank.
- Always store fuel (no more than 5 litres) in a sealed marked container.
- Always keep a B class fire extinguisher nearby.
- Use warning signs to ensure other personnel are aware of petrol and fume dangers
when working on the fuel system.
- Avoid skin contact with petrol and other automotive fuels.
- Be careful. Play by the rules.

ALTERNATOR!

What is an alternator?

An automotive charging system is made up of three major components: the battery, the voltage regulator and an alternator. The alternator works with the battery to generate power for the electrical components of a vehicle, like the interior and exterior lights, and the instrument panel. An alternator gets its name from the term alternating current (AC).

    

BATTERY CHARGING + -

BATTERY CHARGING + -

How to charge a battery:

When changing a battery, battery manufacturers recommend disconnecting the negative ground connection first to prevent accidental short-circuits between the battery terminal and the vehicle frame.

Once you have taken off the battery, take it to a safe area with plenty of ventilation and away from kids, pets, naked flames and sparks.

This battery has the individual caps

This battery has caps under the yellow strip

Before you connect the battery charger, you will need to check the levels inside the battery

If they are low, then you need to top up the cells with 'distilled' or 'de-ionised' water.

Looking into the cells, you can see they have
been filled so that the plates are covered with the electrolyte.

This video from You Tube : http://www.youtube.com/watch?v=CYdR3NVQk3U

CHARGING

If you are leaving the battery on the car then disconnect the negative (black) and positive (red) wires from the battery using the relevant spanner (usually 10mm).

Before you go any further, make sure you have read the manufacturers instructions that come with the battery charger.

With the battery charger unplugged from the electricity supply, connect the black charger clip to the negative ( - ) terminal of the battery and the red clip to the positive ( + ) terminal.

Now plug the car battery charger into the mains and switch it on.

Leave the battery charging overnight and when you check on it in the morning the charger should indicate that the battery is fully charged.

Switch off and then unplug the charger, remove the charger clips from the battery and refit the cell caps / strip.

The battery should now be ready to refit to the car, follow the removal instructions in reverse.

OHMS LAW and ETC

OHMS LAW and ETC

Serises and Parallel Circuits

Series Circuit Rules

1. Current is the same everywhere in the circuit. (kirchoffs Laws)

2. Rt (total Resistance) is the SUM of each resistive unit. (Add them all together)

3. Voltage drop across each resistive unit when added up will equal the applied voltage. (kirchoffs Laws) Or, voltage gets used up pushing throught the circuit, and the part that has more resisitance will use up more voltage.

4. If the resistance of each resistor is different, then the voltage drop will be different across each resistor.

Serise circuit example :

Parallel Circuit Rules

1. At (total amperage) equals the SUM of all CURRENT branches. (Add them all together)

2. Rt is less than any one branch resistance. Rt = (R1 x R2) / (R1 + R2)

3. Applied voltage is the same at all branches.

Parallel circuit example:

W = Watt

V = Volt

I = Amp

R = Resistance

Formulae:

V = I x R

I = V / R

R = V / I

W = I x V

Ps: A proper Circuits needs:

Counductor
Power Source
Load
Switch
Protection Device

WEEK 1

Electrical terms: Electricity
-Electricity is the flow of electrons from atom to atom.
Direct current: (DC)
- Current flows in only one direction.
Alternating current:(AC)
-follows in one direction,then it flows in the other direction.
Diode:
-If power is flowing, the diode will only allow the power to go one way..
In a alternator is has "three" diodes

 NOTE:         Definitions:

-Volt: Practical unit of electromotive force and potential difference.
-Ampere: Unit of current amps.
-Ohms: Unit of resistance.
-Watts: Practical unit of power.
-Farael: Unit of capacitance.
-Hertz: Unit of frequency.

Week 2

we tested out fuses,checked which one is blown.How to find out why the high stop light  is not
working or why the horn is not working.

-W:Watts.                             Horns
-V: Volts.
-A:Amps.               2x12=50                                      12/4.16=0.028 amps
                             50/12= 4.167 amps

Terminal number are 85+86,terminal 85 goes to a earth or ground source.Terminal 86
is supplies power through a swtich to complete the circuit.

Circuit Diagram:                                   voltage-is a power source.
                                                               Ampere-How much current is going threw.
                                                              Diode-is a current that only goes one way.

Type of circuit:
-Glass fuse
-Ceramic fuse
-Blade fuse
-Fusible links
-Thermal circuit breakers

Technique:
-Put a coil around the screw driver, and when this done,
the screw driver becomes a magnet which helps to get to
limited space areas.

Components:
-battery-is a power source
-wire- conductor
-fuse-conductor
-switch- switching device

Function:
-Battery -power source is going threw the relay which is n.o 30,
the battery supplies the power.
-Wires carry it through the fuse. the relays to terminals 30.
-The relays functions as a remote switch. The main current flows from the battery to
the user or headlight bulb.It is activated by a low current coil that acts as a magnet to
close the switch.

30-battery input
87- normal headlight power

Note: when power is on, the coil becomes a magnet which pulls the switch to 87 and turns on the headlight and when power is off, there will beon magnet coil and that causes no headlights to be working.

Whats is a circuit?

-A circuit is a closed loop that electrons can travel in a source of electricity,such as a battery,provides electrical energy in the circuit.Unless the circuit is complete, that is, making a full circle back to the  electrical source ,no electrons will move.

Volts= Amps x resistance
Resistance=Volts/ amps
Amps=volts/ resistance

Compenents:      TERMS:

-Conductor-Material forming path for the flow of current.
-Insulator-Material that will not readily conduct electricity.
-Negative charge-The flow of current fro  negative to positive.
-Semi conductor-Materials that act as conductors or insulators depending
on temperature ,physical or electrical conditions.
-Positive charge-The flow of current from positive to negative.
-Electron current flow-Electron.
-Conventional current flow- proton
-Watts-practical  power unit.

DIFFERNCE BETWEEN SERIES AND PARALLEL