09/06/2014 questions

1) What are the S.O.P. for using the lathe? No loose items to be worn, hair tied up and stored under overalls, Make sure the object is properly inserted and locked up before starting, Do not insert your hands near the object when it is sinning.

2) Why is it important to use cutting oil when drilling? The oil helps to lubricate the drill piece as well as help to disperse heat while drilling.

3) What direction do you weld when using a MIG with no flux? left to right.

4) What Volts & Amps do you set the MIG welder to when welding thin metal? 23.5V & 8A

5) What does MIG welding mean? Metal Inert Gas, Using an inert gas means that it will not react with the metal and welding and will keep contaminants out of the weld.

6) What are the tools used to mark the line on the metal? Scriber

7) If you are on 25mm and you make three turns of the thimble, where are you now? 26.5mm

8) What are the five main welds we have done? Butt Joint, Lap Joint, 90* inside, 90* outside, T joint

9) which way do you set the lathe to cut the metal? anti clockwise

10) What colour are the hoses on the gas welding equipment? Red for gas Blue for Oxygen.

Monday 19/05/2014

Why do we use an engineering square?   Engineering squares have a proper 90* right angle on the inside which we use to check if other objects have a right angle and are level.

When we use a lathe do we cut clockwise or anti-clockwise? anti clockwise

why do we centre punch before drilling? without centre punching the object will still be smooth causing the drill piece to slip and slide and not drill. Centre punching will make a small indent for the drill piece to sit in and allow it to drill without slipping.

when making the drill gauge what size drill bit do we use? 4mm, 6mm, 8mm, 10mm, 12mm

what psi/bar do you set the gas welding gauges on? acetylene=3 oxygen=10

What are the S.O.P. for using the drill press?

Why do we us cutting oil when drilling? Cutting oil is used to help lubricate and heat dispersal to keep the drill bit cool and prevent breaking.

When using a micrometer, if it is set to zero & we we turn it two turns on the thimble, what would it be reading? 1mm

What is the difference between fusion and brazing welding? Fusion is where you heat the metal up so much that it starts to liquefy and then you start moving this liquid and meshing them together to bridge the gap. Brazing you heat the brazing rod and dip it in flux. Heat the metal till it is red then start melting the brazing mixture in to fill the gap.

What two files do we use? Bastard (rough) and soft file to clean it off.

What are the five joints we do in the welding? butt joint, lap joint, inside right angle, outside right angle, and ash tray.

What angle is the drill gauge set to? 58*

what is the tool called to set this angle? bevel ruler.

If you cant get a good flame with the oxyacetylene welding, what should you do with the nozzle? Use the pokey rod thingies to poke into the nozzle to clean it.

Which way should the blade be facing on a hacksaw? Facing forward with teethe back towards handle.

Engineering Technology 2014

Inertia starter motor and pre-engage starter motor.

Inertia Starter Motor:

With the inertia starter motors they power was added and the ring gear would spin at full speed. The gear would then spin inwards due to inertia along the grooved lines and hit the flywheels gears at full speed. This was such a harsh event that it would grind, break or mangle the ring gear and flywheel teeth.

Pre-engage starter motor:

when you engage the starter motor the pinion gear gets pushed out onto the flywheel, this step is the stop that violent event of the pinion gear and flywheel meshing. This has the negative effect of the starter needing a lot of power to overcome its own inertia and then the inertia of the motor. 

Ignition circuit diagram

Word search

Electrical Paper Test 2

1. What is the colour of a 10A fuse?  Red.
2. What is the total resistance in the circuit? 12A
3. The fuse is missing from a circuit. How do you measure & workout the correct fuse to replace? Check the fuse box cover. V=IxR  I= V/R. Measure before the fuse box and check with the components Amp rating.
4. What is the total resistance? 7A
5. Customer comes in with the passenger window N/W, What is the correct procedure to take? Measure the voltage at the connection. If good V then put a battery straight to the motor, if it works there must be a bad connection. If no Voltage at the connection, trace back to the switch. If good V at switch check the resistance for voltage drop. 
6. What colour is a 20A fuse? Yellow. 
7. Is the brake light bulb series or parallel? Parallel.
8. How does the central locking work on the front left door? When you lock or unlock the driver door, an electric motor lock or unlocks the passenger door. In the older cars they used vacuum hoses to lock and unlock. When you lock the door the vacuum sucks the lock shut when you unlock the vacuum pushes the lock open.
9.         What does this symbol mean and where would it be found in the car?  Stops the flow of electricity flowing backwards through the circuit and converts AC into DC in the alternator.
10. If a fuse doesnt work, how do you check it out? Get a test light and clip the alligator clip onto an Earth point. Apply power to the fuses, probe the pointy end into the fuses. One side should light up the test light but the other side should remain dead.
11. What is vvvvvvv and where would you find this on a car? Alternator. This is where the rectifier pack converts the AC into DC.
    
12. What Watts is a headlight bulb? This can vary but generally 50W on dip and 70W on high beam.
13. Explain how a relay works including both circuits? A relay is like a switch. When the relay receives low current input it opens or closes a switch which then allows high current to flow through the relay and power up a component. 
14. what is missing? V/   =R    IxR=              V/I=R    IxR=V
15. What is Voltage? Voltage is the strength of electricity flowing through a circuit.
    What is Amps? Amps is the amount of electricity flowing through the circuit.
    What is Resistance? Resistance is the force opposing the flow of electricity.

Electrical paper test

1) What is the correct PPE to be worn when carrying a battery.
     Safety Boots, coveralls, gloves, safety goggles
2) When charging a battery what are the five things you should do.
   Battery off the ground, keep away from metal, use a trickle charger, stable platform as not to spill it
3) What is the correct procedure to removing a starter motor.
   Remove battery terminals, remove wires from the starter motor. remove the 2 bolts holding the SM to the flywheel.
4) Three components used to check a battery.
   Volt meter, Hydrometer, Load Tester.
5) What is a short circuit.
  A short circuit is when a source of high resistance finds a path to ground of low resistance causing a spark.
6) What is a parallel circuit.
   A parallel circuit is when a source of power splits into two or more paths before joining back together.
7) When the car is running at idle, what voltage should be read on the alternator.
   14.5V
8) If the battery warning light is not working, what does this mean for the alternator.
   The light is complete on the alternator. this is to give it a little start to charge and keep it going.
9) What is the purpose of a relay.
   A relay is like a switch which receives a low current signal and open the pathway for a high current source to be complete.
10) What is Volts and Amps.
   Volts is the strength of the electrical charge and Amps is the amount of charge going through the circuit.
11) When using a multimeter, how should you connect in volts and amps.
   Volts should be connected in parallel with the components or wires, Amps should be in series with components.
12) When checking a battery, what are the SOP.
   accidentally shorting the battery. Keep the terminals clear, use the voltmeter and use each prong on the terminal.
13) What is the difference between the Alternator belts.
   V belt and Poly-V belt.
14) First two stages of a Starter Motor.
   When you turn the key the bendix engages pulling the lever, pushing the wheel out onto the flywheel. the second stage then engages and spins the wheel which turns the flywheel turning the motor over.
15) What is an Alternator and what is a starter motor.
   An Alternator charges the battery and a starter motor only starts the battery then its job is done.
16) What is the difference between the two.
   The alternator contains copper inside with magnets spinning on the inside using the belt. This creates a magnetic field, this charges the battery. The starter just spins the flywheel.
17) What is the acid inside the battery.
   Sulfuric acid
18) What is the 3 main numbers in the electrical module.
   30 positive 31 ground 15 ignition
19) What is voltage drop and how is it tested.
   voltage drop is when there is a significant drop in voltage across a wire or component. Use a voltmeter to check between battery 12.6V to the component which might be 6V
20) What component in the ALT converts AC to DC.
   The rectifier pack

TTEC3201 Electrical Technology

Industry Practice

Copy of TTEC 3206 Vehicle Technology

Engine diagram

Coolant Systems Q&A

Tuesday, August 13, 2013

Coolant system questions

1. What is the purpose of the water pump? Pumps the coolant through the engine using pressure.
2. How much energy is converted in to mechanical energy? 25%
3. What are the three ways of heat transfer? Convection, conduction, radiation.
4. What is the purpose of coolant? Anti freeze lowers freezing temp. raises boiling temp. lubricates the hoses and water jackets.
5. What are the main components of a cooling system. Radiator, Hoses, water pump, thermostat, heater
6. Why do we need flexible water hoses on the cooling system? As the engine runs it shakes, vibrates and moves around and firm solid pipes will stop the movement.
7. Why are coolant hoses reenforced?as the pressure builds the hoses start to bulge
8. How is the water pump driven? by pulleys on the pump and crankshaft drivn by a belt.
9. What is the water jacket? holes that are blasted into it and these form passage ways for the water to flow through and cool the engine.
10. What is the purpose of the thermostat? One way valve that when hot opens up and allows water to flow from the head to the radiator.
11. What is the purpose of the cooling fan? when idle-ing the fan turns on to pull cold air through the radiator.
12. Why do some cars have two cooling fans? Air Conditioning
13. On electric cooling fans, what switches the fans on and off? a temp sensor in the heads water jacket that switches on whe it reaches 90 degrees.
14. How does the temperature gauge work? the temp sensor in the head water jackets that works on resistance. When cold it has a lot of resistance and as it warms up there is less resistance as the particles expand and move apart.
15. Why do we have a radiator pressure cap? this keeps pressure in the cooling system, pressure raises the boiling point. When there is too much pressure it relieves the pressure from extra water into the overflow bottle and when there is not enough pressure a vacuum is created which sucks water back into radiator.
16. Why do we have a recovery bottle? store extra coolant and catches the overflow and lets water back into the system.
17. What is electrolysis? sparking of electricity using DC current to drive a chemical reaction, used for separating ores.

Engine Compression Test

Steps to testing the compression
Remove ignition leads
Remove spark plugs
Insert hose from the compression tester into the spark plug hole.
crank the engine for 5 seconds with foot flat
write down the reading of compression test
do the same test on the same cylinder but with a little bit of oil on the piston head, this is called a wet test
crank the engine again for 5 seconds
write down the reading of compression test
do the same for the next cylinder
if there is a 10 - 15% difference between cylinders there is a problem with the cylinder


Safety precautions
disconnect the ignition system
turn off injectors
do not drop spark plugs
do not insert hose further into the cylinder than what the spark plug would sit

Work experience

Here is the work I do on Fridays as my work experience.

I changed the head gasket on a subaru legacy. I was able to use the hydraulic lift to lift a second car up and walk around underneath and remove the exhaust for removal of the engine.

Torque Settings

Your morning work "Torque Setting"

Hi guys, use the following web site to find the engine torque setting for the engine that we are current working on in the workshop

Engine make:  Mazda
Engine model: B6

Web Site:   www.autodataonline.co.nz/

Find out the follow torque setting

Cylinder head bolts
Rocker cover bolts

1. Camshaft pulley bolt   30nm, 50nm, 76 - 81nm
2. Spark plugs  15 - 23nm
3. Fly wheel bolts  100nm
4. Sump drain bolts 30 - 45nm
5. Sump bolts  10nm 
6. Main bearing bolts stage 1= 15 - 23nm stage, 2= 54 - 59nm
7. Big end bearing bolts stage 1= 25nm, stage 2= 50 - 54nm
8. Intake manifold to cylinder head bolts 20 - 25nm
9. Crankshaft pulley bolt 108 - 128nm

Answers to Questions

What is the purpose of a glow plug? Cold starts on diesels, warms the air inside the cylinder.

What does B.D.T.C means ? Before Top Dead Centre, this is about 5% - 16% before top dead centre

When the piston travel at T.D.C and both valves are close, what stroke is it? compression

How many time the camshaft turns in a 4 stroke cycle? 1 time

What is the purpose of thrust washers? any object spinning in a clockwise direction has a tendency to drive forward, the thrust washers allow the crank to spin without driving forward.

Name all the components of the valve assembly? valve, valve spring, collet, seals, retainer shield.

What is the purpose of the tag on the bearing shells? this stops the shells from spinning around the bearing, allows oil to flow through the little holes.

What compresses the volume of air and fuel? piston crown

Why is it important to time you engine up correctly? The piston could come up an hit one of the valves and break the valve. rough idle

What is a stroke? when the piston travels between BDC and TDC and vica versa

What drives the cams? camshaft, cambelt

What is the block made of? cast iron

Why is core plug fitted?

What is the purpose of the pistons? compress the air and fuel mixture and then when those get ignite the explosion force pushes down on the piston crown which goes down and turns the crankshaft.

What is the advantages of having aluminium head? better heat distribution, light weight.

Engine Technology

Internal Combustion Engine