Clutch Flashcards
Purpose of the spigot bearing
Supports end of gearbox input shaft
Allows differential of speed between crankshaft and gearbox input
Types of spigot bearing and info about them
Ball type bearing - heavy duty, interference fit, floating sealed for life
Phosphor bronze type - light to medium duty, interference, solid bush, self lubrication
What is the friction plate also known as?
Driven plate
Centre plate
How do you over come buckling of the outer hub in the friction plate?
The outer hub is slotted to allow flexing action
What dose having alternatively placed fixings segments of the outer hub do?
Create a wavy profile (borglite crimping)
borglite crimping increased the axial compression which has what effects?
Allows a smoother engagement of drive
Increases airflow between segments enhancing cooling
Purpose of the damper springs?
Transmit drive
Absorb torsional shocks during drive engagement from engine vibration and during overrun
The damper springs, what 2 things can they be ?
Springs
Rubber blocks
Functions of the pressure plate?
Provide a flat driving face that mates with friction plate
Provide a clamping force on to the friction plate to transmit drive
Advantages of diaphragm spring?
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
Why is there a lip cast on the reverse of the pressure plate casting?
To accommodate rim of the diaphragm spring
What are the lugs for on the pressure plate casting for?
To allow connection of drive straps
What are the drive straps made of and what do they do?
Spring steel
Transmit drive from the cover to the pressure plate
What holds the fulcrum ring in place?
Turn over taps or rivots
Tell me about the multi coil spring?
Bulky and expensive
Prone to centrifugal effects
Larger pedal force required
Clamping forces decreases as friction linings wear
On a multi coil spring, how many release leavers are fitted and what is the alternative name?
Toggle leaver
3 or more
Components of the release leaver?
Knife edge
Eye bolt
Anti rattle spring.
In the release leaver what dose the knife edge do?
Acts as double pivot point between the release leaver and pressure plate
Ensures the pressure plate moves squarely in relation to the centre plate
What is the alternative to drive straps?
Drive lugs
On the multi plate clutch. What factors decide what torque is transmitted?
Size of clutch (radius)
Pressure applied
Area of contact for the centre plate
2 main types of multi plate clutch?
Wet
Dry
What’s the difference between a normal friction clutch and a multi plate dry clutch?
Multi plate dry clutch has an addition of a second friction plate and an intermediate plate
On the multi plate dry clutch, where are there extended securing studs?
To guide the intermediate plate, and also give positive drive
2 types of release bearing?
Ball race bearing
Solid bonded carbon pad
2 types of release arms? And what they for?
Pressed steel - light to medium duty clutches
Drop forged steel - heavy duty clutches
Why is FPM clearance needed?
Prevents premature wear
Ensures full spring pressure acts on the pressure plate when clutch (drive) is engaged
2 methods of clutch operating mechanisms?
Mechanical - cable and rod
Hydraulic
2 types of Manuel cable adjustment? (Clutch)
Motorcycle cable adjuster
Car cable adjuster
What is the automatic cable adjuster called?
Quadrant and pawl
Clutch faults?
Slip Drag Judder Fierceness Bearing noise
Symptoms of clutch drag?
Difficulty engaging 1st or reverse from neutral
Jolts when changing gear
Vehicle keeps moving when clutch is depressed
Symptoms of clutch slip?
Revs increase and no change in vehicle speed
Burning smell
Not go up hills
Symptoms of clutch judder?
Vibrations
Symptoms of fierceness?
Sudden engagement
Symptoms of bearing noise?
Bearing noise
Noise goes away when clutch is released
3 main differences of a torque converter and a fluid flywheel?
Contains a stator
Vanes are angled
2 flow control rings
