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CLUTCH_PETROL
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6. MAINTENANCE, TESTS AND FACTOR AFFECTING
A. INSPECTION OF COMPONENTS
i. Check clutch disc hub splines for damage and wear.
ii. Check torsion damper mechanism springs for distortion, damage etc. For this purpose, hold drive shaft in
vice. Insert clutch disc and slide it as far back as possible. Rotate disc by hand. Rattling noise and excessive
play indicates damaged torsional damping mechanism and such disc must be replaced.
iii. Check disc facing for wear, cracks, contact pattern, burning marks and oil contamination. Facings with any
of the above defects or worn out beyond permissible limits must be replaced.
iv. Check the correct position of clutch pedal lever, which should be In-line with the brake pedal lever, (During
every service check the clutch pedal lever is ln-line with brake pedal, if not set in-line with the brake pedal
lever).
B. TEST
1. CLUTCH SLIPPAGE TEST
Clutch slippage can be confirmed by any of the following two methods:
i. Drive the car in 1st or 2nd gear at maximum speed corresponding to that gear. Keeping the accelerator
pedal pressed with your right foot, apply brake gradually with your left foot If the engine stalls, it means that
clutch does not slip.
ii. Drive loaded car in 3rd gear on level ground and let the speed drop down to approximately 15 kmph. Now
press the accelerator pedal fully. With slipping clutch, the car speed will not pick up and also clutch burning
smell will be noticed. If this does not occur and the car picks up speed, it indicates that clutch does not slip.
2. CLUTCH ENGAGEMENT AND DISENGAGEMENT TEST
During the clutch slippage test, when the car is in motion, depress clutch pedal fully without changing the
accelerator pedal position. If the engine speed increases immediately, perfect clutch disengagement is
indicated. Further, release the clutch pedal suddenly. If the car moves forward with a little jerk, perfect clutch
engagement is indicated.
C. FACTORS AFFECTING CLUTCH
The clutch is designed to give maximum life under most severe conditions when handled carefully. However,
while in operation, clutch lining is subjected to wear. Apart from this the extent of wear also depends on
following driving conditions.
Following driving conditions will affect the performance of the clutch.
i. Clutch riding
Using clutch pedal as foot rest by keeping foot constantly on pedal while driving will cause partial clutch
disengagement. It will result in slipping of the clutch disc and premature failure of the clutch.
ii. Permitting the clutch to slip too long
Half clutch driving and thereby permitting the clutch purposely to slip too long will have the same result as
above.
iii. Permitting the clutch to jerk
Sudden clutch engagement at higher engine speed specially while moving out the stuck car will cause severe
instantaneous clutch loading, resulting in clutch slippage and burning of the lining locally. Starting the car in
first gear under such conditions will avoid such problem. Always start the car in first gear.
iv. Restarting on gradient:
While restarting the car on gradient, make use of parking brake. Half clutch driving while restarting on the
gradient will cause premature damage to clutch