between the flywheel and the flange. If the flange is
bent, the crankshaft must be replaced.
Other causes of clutch pedal pulsation include bent
or maladjusted pressure plate release levers, warped
pressure plate, or warped clutch disc. If either the
clutch disc or pressure plate is warped, they must be
When adjustment or repair of the linkage fails to
remedy problems with the clutch, the clutch must be
removed for inspection. Any faulty parts should be
discarded and replaced with new or rebuilt
components. If replacement parts are not readily
available, a decision to use the old components should
be based on the manufacturers recommendations and
the maintenance supervisor.
Transmission or transaxle removal is required to
service the clutch. Always follow the detailed
directions in the service manual. To remove the clutch
in a rear-wheel drive vehicle, remove the drive shaft,
the clutch fork, the clutch release mechanism, and the
transmission. With a front-wheel drive vehicle, the
axle shafts (drive axles), the transaxle, and, in some
cases, the engine must be removed for clutch repairs.
When the transmission or transaxle is
removed, support the weight of the engine.
Never let the engine, the transmission, or the
transaxle be unsupported. The transmission
input shaft, clutch fork, engine mounts, and
other associated parts could be damaged.
After removal of the transmission or transaxle,
remove the clutch housing from the rear of the engine.
Support the housing as you remove the last bolt. Be
careful not to drop the clutch housing as you pull it
away from the dowel pins.
Using a hammer and a center punch, mark the
pressure plate and flywheel. These marks are needed
when reinstalling the same pressure plate to assure
correct balancing of the clutch.
With the clutch removed, all components are to be
cleaned and inspected for wear and damage. After
cleaning, you should inspect the flywheel and pressure
plate for signs of unusual wear, such as scoring or
cracks. A straightedge should be used to check for
war-page of the pressure plate. Using a dial indicator,
measure the runout of the flywheel. The pressure plate
release levers should show very limited or no signs of
wear from contact with the release bearing. If
excessive wear, cracks, or warpage is noted on the
flywheel and/or pressure plate, the assembly should be
replaced. This is also a good time to inspect the ring
gear teeth on the flywheel. If they are worn or chipped,
a new ring gear should be installed.
Be careful how you clean the parts of the
clutch. Avoid using compressed air to blow
clutch dust from the parts. A clutch disc con-
tains asbestosa cancer-causing substance.
While inspecting the flywheel, you should check
the pilot bearing in the end of the crankshaft. A worn
pilot bearing will allow the transmission input shaft and
clutch disc to wobble up and down. Using a telescoping
gauge and a micrometer, measure the amount of wear in
the bushing. For wear measurements of the pilot
bearing, refer to the service manual. If a roller bearing
is used, rotate them. They should turn freely and show
no signs of rough movement. If replacement of the
pilot bearing is required, the use of a slide hammer
puller will drive the bearing out of the crankshaft end.
Before installing a new pilot bearing, check the fit by
sliding it over the input shaft of the transmission. Then
drive the new bearing into the end of the crankshaft.
Inspect the disc for wear; inspect the depth of the
rivet holes, loose rivets, and worn or broken torsion
springs. Check the splines in the clutch disc hub for a
"like new" condition. The clutch shaft splines
should be inspected by placing the disc on the clutch
shaft and sliding it over the splines. The disk should
move relatively free back and forth without any
unusual tightness or binding. Normally, the clutch
disc is replaced anytime the clutch is tom down for
Another area to inspect is the release bearing. The
release bearing and sleeve is usually sealed and factory
packed (lubricated). A bad release bearing will
produce a grinding noise whenever the clutch pedal is
pushed down. To check the action of the release
bearing, insert your fingers into the bearing; then turn
the bearing while pushing on it. Try to detect any
roughness; it should rotate smoothly. Also, inspect the
spring clip on the release bearing or fork. If bent, worn,
or fatigued, the bearing or fork must be replaced.