Indicator:

Shudder/Judder

Cause:

1. Excessive heat generated within the clutch components - Overloading the clutch
2. Carrying excessive loads - Overloading the vehicle
3. Incorrect clutch free travel
4. Incorrect driving practices (Riding the clutch)
5. Poor flywheel grinding surface finish

Effect:

Pressure plate surface and/or the flywheel surface are excessively glazed and has a mirror type finish.

Action:

1. Replace clutch kit
2. Check clutch control mechanisms and if necessary repair or replace.
3. Correct clutch free travel settings
3. Driver education

» Link to Guide

Indicator:

Poor pedal feel/Clutch Slipping

Cause:

1. The clutch kit is worn beyond its service life
2. Incorrect installation
3. Incorrect clutch free travel settings
4. Faulty clutch hydraulics
5. Incorrect flywheel step

Effect:

Clutch self-adjusting mechanism has moved to its fully worn out position.

Action:

1. Replace Clutch Kit
2. Check clutch hydraulics and repair or replace if necessary
3. Set correct clutch free travel
4. Verify correct flywheel step
5. Use self-adjusting fitting tool for the fitting process

A guide for installing a self-adjusting clutch cover can be found here.

» Link to Guide

Indicator:

Slipping/Poor clutch engagement or dis-engagement/Metallic Noise at the bottom of the pedal

Cause:

Insufficient clearance between the release bearing and the clutch operation spring

Effect:

1. Clutch diaphragm spring has excessive wear
2. Clutch diaphragm spring has broken
3. Release bearing shows signs of fatigue (notchy or seized)

Action:

1. Replace clutch kit
2. Inspect the clutch operating system and repair or replace if necessary (Pivot Ball, Release Fork, Cross Shafts,  Master Cylinder, Slave Cylinder, Clutch Cable and Pedal Box).
3. Set correct clutch free travel

» Link to Guide

Indicator:

Slipping clutch/Incorrect clutch operation

Cause:

1. Bell housing has not been degreased and cleaned. Poor installation of the new clutch. The new clutch disc has not worn but fibres have become lodged in the new clutch cover are that of the previously worn clutch. It is a requirement due to ventilation designs that the bell housing area free from old fibres, dirt and grease when installing new clutch.
2. This problem is common in 4 wheel drive vehicles when an inspection cover or a clutch fork cover boot has not been Inspected for re-use or replaced when installing a new clutch.

Effect: 

Worn clutch disc facing fibres and/or dirt lodged between diaphragm spring and clutch cover housing causing loss of cover clamping force.

Action:

1. Ensure the bell housing and back of the engine are thoroughly degreased and cleaned of foreign material before installing a new clutch.
2. Ensure inspection locations are sealed correctly with any boots thoroughly inspected for re-use and if necessary replaced. (Note: These problems are common on farm vehicles, vehicles travelling on sand and 4x4 recreational vehicles.)

» Link to Guide

Indicator:

Clutch Slipping/Noisy in operation

Cause:

Pressure plate assembly hold down bolts have not been removed after the pressure plate has been mounted and torqued to the flywheel.

Effect:

1. Hold down/Shipping bolts not removed and slipping when a new clutch has been installed
2. Unable to get correct clutch free travel adjustment
3 Unable to get correct clutch operation

Action:

Remove hold down bolts (Do not remove or adjust the clutch lever adjustment nuts/bolts)

» Link to Guide

Indicator:

Slipping clutch/Judder.

Cause:

1. Excessive grease used upon installation (Bearing Slide and/or shaft splines)

2. Incorrect lubricant

3. Rear main seal leak

4. Front gearbox seal leak

5. Poor practice of cleaning the clutch components prior to installation.  

Effect:

Oil/Grease or other contaminants on the friction surfaces.

Action:

1. Replace Clutch kit
2. Lightly grease spline, wipe off excessive grease after tentative installation and ensure there is smooth sliding of clutch disc on main drive shaft.
3. Remove any excessive grease from the bearing slide after tentative installation.
4. Clean pressure plate surface and flywheel surface with a non-oil based solvent (Mentholated Spirits, Thinners or Brake Clean)
5. Inspect all engine and gearbox seals and if necessary replace.

» Link to Guide