Symptoms and probable causes
1. Slippage
The clutch slipping will appear gradually with the followings.
a. No speed gain
b. Fuel consumption increases
c. Engine overheats
d. Not enough acceleration relative to engine rpm when the accelerating
pedal is depressed suddenly
e. Loss in power is evident when climbing a slope
The clutch slippage can be detected immediately in case of “d” and “e”,
but as for the symptoms of “a”, “b” and “c”, they are sometimes taken
for engine troubles. Thus, diagnosis must be carefully made. Try not
to operate the car with a slipping clutch which may lead to excessive wear
or burning of clutch facing.
INSPECTION: Pull the parking brake fully and lock the wheels completely.
Disengage the clutch by depressing clutch pedal, then engage
transmission gear in the first speed position. Slowly engage the clutch
while increasing the engine rpm gradually. If the engine begins to stall,
the clutch is in good condition. If the car does not move and the engine
does not stall, the clutch is slipping.
| a. No clutch pedal play | Adjust |
| b. No play at release fork end | Adjust |
| c. Oil adhering to clutch facing | Replace |
| d. Clutch facing worn out | Replace |
| e. Weak compression spring | Replace |
| f . Deformed pressure plate and/or
flywheel |
Repair or replace |
2. Improper Disengagement
This symptom causes unpleasant noise (crunch) when shifting the trans-
mission gears into mesh, and makes the gearshift difficult. Especially this
appears when shifting into low gears.
INSPECTION: Depress the clutch pedal and engage the gears, next
position in neutral. Accelerate the engine, then engage the gears again.
At this time keep the clutch pedal depressed. If the noise is still present,
the clutch may be defective.
| a. Excessive clutch pedal play | Adjust |
| b. Excessive play at release fork end | Adjust |
| c. Defective input shaft front bearing | Replace |
| d. Worn splines of clutch disc hub | Replace disc assembly |
| e. Excessive clutch disc run-out | Repair or replace |
| f . Weak or deformed master cylinder
piston cup |
Replace piston cup or complete master cylinder |
| g. Fluid leakage from master cylinder
piston gasket |
Replace gasket or complete master cylinder |
| h. Fluid leakage from release cylinder
piston gasket |
Replace gasket or complete master cylinder |
| i . Air in clutch hydraulic system | Bleed air |
3. Chattering
Upon starting out the car with the clutch engaged half-way, entire body
may vibrate.
| a. Clutch facing glazed | Recondition the facing with
sandpaper or replace |
| b. Oil on facing | Replace |
| c. Damaged or weak disc torsion
rubbers |
Replace disc assembly |
| d. Poor facing contact or excessive
disc run-out |
Replace disc assembly |
| e. Warped pressure plate or flywheel | Repair or replace |
| f . Loose engine mounting | Tighten or replace |
| g. Loose rivets in clutch disc | Replace |
4. Noisy
Find the origin of the noisy clutch by disengaging the clutch “a” and “b”,
engaging clutch “c” , “d” and “e” .
| a. Damaged, worn or improperly
lubricated release bearing |
Replace |
| b. Damaged or worn input shaft front
bearing |
Replace |
| c. Loose disc hub | Replace disc assembly |
| d. Cracked disc plate | Replace disc assembly |
| e. Weak or damaged disc torsion
rubbers |
Replace disc assembly |
5. Jerking
Upon starting out the car with the clutch engaged half-way, the car jerks
and is not accelerated smoothly.
| a. Oil on facing | Replace |
| b. Worn facing or loose rivets | Replace disc assembly |
| c. Damaged or weak disc torsion
rubbers |
Replace disc assembly |