Clutch

Question 1

Purpose of the spigot bearing

Answer 1

Supports end of gearbox input shaft

Allows differential of speed between crankshaft and gearbox input

Question 2

Types of spigot bearing and info about them

Answer 2

Ball type bearing - heavy duty, interference fit, floating sealed for life
Phosphor bronze type - light to medium duty, interference, solid bush, self lubrication

Question 3

What is the friction plate also known as?

Answer 3

Driven plate

Centre plate

Question 4

How do you over come buckling of the outer hub in the friction plate?

Answer 4

The outer hub is slotted to allow flexing action

Question 5

What dose having alternatively placed fixings segments of the outer hub do?

Answer 5

Create a wavy profile (borglite crimping)

Question 6

borglite crimping increased the axial compression which has what effects?

Answer 6

Allows a smoother engagement of drive

Increases airflow between segments enhancing cooling

Question 7

Purpose of the damper springs?

Answer 7

Transmit drive

Absorb torsional shocks during drive engagement from engine vibration and during overrun

Question 8

The damper springs, what 2 things can they be ?

Answer 8

Springs

Rubber blocks

Question 9

Functions of the pressure plate?

Answer 9

Provide a flat driving face that mates with friction plate

Provide a clamping force on to the friction plate to transmit drive

Question 10

Advantages of diaphragm spring?

Answer 10

Compact and lightweight 
Less moving parts 
Suitable for high engine speeds 
Not affected by centrifugal force 
No vibrations due to spring imbalance
Lower pedal force required 
Clamping force dose not reduce as friction lining wear

Question 11

Why is there a lip cast on the reverse of the pressure plate casting?

Answer 11

To accommodate rim of the diaphragm spring

Question 12

What are the lugs for on the pressure plate casting for?

Answer 12

To allow connection of drive straps

Question 13

What are the drive straps made of and what do they do?

Answer 13

Spring steel

Transmit drive from the cover to the pressure plate

Question 14

What holds the fulcrum ring in place?

Answer 14

Turn over taps or rivots

Question 15

Tell me about the multi coil spring?

Answer 15

Bulky and expensive
Prone to centrifugal effects
Larger pedal force required
Clamping forces decreases as friction linings wear

Question 16

On a multi coil spring, how many release leavers are fitted and what is the alternative name?

Answer 16

Toggle leaver

3 or more

Question 17

Components of the release leaver?

Answer 17

Knife edge
Eye bolt
Anti rattle spring.

Question 18

In the release leaver what dose the knife edge do?

Answer 18

Acts as double pivot point between the release leaver and pressure plate
Ensures the pressure plate moves squarely in relation to the centre plate

Question 19

What is the alternative to drive straps?

Answer 19

Drive lugs

Question 20

On the multi plate clutch. What factors decide what torque is transmitted?

Answer 20

Size of clutch (radius)
Pressure applied
Area of contact for the centre plate

Question 21

2 main types of multi plate clutch?

Answer 21

Wet

Dry

Question 22

What’s the difference between a normal friction clutch and a multi plate dry clutch?

Answer 22

Multi plate dry clutch has an addition of a second friction plate and an intermediate plate

Question 23

On the multi plate dry clutch, where are there extended securing studs?

Answer 23

To guide the intermediate plate, and also give positive drive

Question 24

2 types of release bearing?

Answer 24

Ball race bearing

Solid bonded carbon pad

Question 25

2 types of release arms? And what they for?

Answer 25

Pressed steel - light to medium duty clutches

Drop forged steel - heavy duty clutches

Question 26

Why is FPM clearance needed?

Answer 26

Prevents premature wear

Ensures full spring pressure acts on the pressure plate when clutch (drive) is engaged

Question 27

2 methods of clutch operating mechanisms?

Answer 27

Mechanical - cable and rod

Hydraulic

Question 28

2 types of Manuel cable adjustment? (Clutch)

Answer 28

Motorcycle cable adjuster

Car cable adjuster

Question 29

What is the automatic cable adjuster called?

Answer 29

Quadrant and pawl

Question 30

Clutch faults?

Answer 30

Slip 
Drag
Judder 
Fierceness 
Bearing noise

Question 31

Symptoms of clutch drag?

Answer 31

Difficulty engaging 1st or reverse from neutral
Jolts when changing gear
Vehicle keeps moving when clutch is depressed

Question 32

Symptoms of clutch slip?

Answer 32

Revs increase and no change in vehicle speed
Burning smell
Not go up hills

Question 33

Symptoms of clutch judder?

Answer 33

Vibrations

Question 34

Symptoms of fierceness?

Answer 34

Sudden engagement

Question 35

Symptoms of bearing noise?

Answer 35

Bearing noise

Noise goes away when clutch is released

Question 36

3 main differences of a torque converter and a fluid flywheel?

Answer 36

Contains a stator
Vanes are angled
2 flow control rings