HEXA

642 / 1906

CLUTCH
14
3.1.2 MAINTENANCE, INSPECTION AND TESTS
3.1.2.1 PRELIMINARY INSPECTION
Clutch needs replacement mainly on
account of clutch slippage or imperfect
engagement and disengagement. This may be due
to worn out/ damaged clutch parts. It is desirable to
carry out the following preliminary checks before
removal of clutch for replacement if the parts.
1. CLUTCH SLIPPAGE TEST
Clutch slippage can be confirmed by any
of the following two methods:
a) Drive the vehicle in 1st or 2nd gear at maximum
speed corresponding to that gear. With
accelerator pedal fully pressed, apply brake
gradually with your left foot. If the engine stalls,
it means that clutch does not slip.
b) Drive loaded vehicle in 3 rd gear on level ground
and let the speed drop down to approximately
15 Kmph / 9 mph. Now press accelerator pedal
fully. With slipping clutch, the vehicle speed will
not pick up and also clutch burning smell will be
noticed. If this does not occur and vehicle picks
up speed, it indicates that clutch does not slip.
2. CLUTCH ENGAGEMENT AND
DISENGAGEMENT TEST
During the above test, when vehicle 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 vehicle moves forward
with a little jerk, perfect clutch engagement is
indicated.
 CAUTION
 This test should be carried out with utmost
care because sudden release of the clutch
might cause heavy jerk and damage to the
clutch lining.
 FACTORS AFFECTING CLUTCH WEAR
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.
A. PROPER MAINTENANCE
Improper maintenance may lead to clutch
wear and improper functioning.
Preventive Maintenance of clutch includes
checking oil level and bleeding the system for
defect free operation of clutch actuation
mechanism.
B. DRIVING
Following driving conditions will affect the
performance of the clutch.
 CLUTCH RIDING
Using clutch pedal as a 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.
 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.
 PERMITTING THE CLUTCH TO JERK
Sudden clutch engagement at higher
engine speed specially while moving out the stuck
vehicle will cause severe instantaneous clutch
loading, resulting in clutch slippage and burning of
the lining locally. Starting the vehicle in first gear
under such conditions will avoid such problem.
Always propel the vehicle in first gear