2002 JEEP LIBERTY Workshop Manual

BRAKES
TABLE OF CONTENTS
page page
POWER BRAKE BOOSTER
REMOVAL - RHD........................1INSTALLATION - RHD.....................1
POWER BRAKE BOOSTER
REMOVAL - RHD
(1) Remove the air box (Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER ELEMENT -
REMOVAL).
(2) Relocate the cruise control servo to gain access
to the booster for removal.
(3) Remove the brake lines from the master cylin-
der.
(4) Remove the master cylinder (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/MASTER
CYLINDER - REMOVAL).
(5) Disconnect vacuum hose from booster check
valve.
(6) Remove knee blocker under the steering colum-
n,(Refer to 23 - BODY/INSTRUMENT PANEL/KNEE
BLOCKER - REMOVAL).
(7) Remove the brake light switch.(Refer to 8 -
ELECTRICAL/LAMPS/LIGHTING - EXTERIOR/
BRAKE LAMP SWITCH - REMOVAL)
(8) Remove retaining clip that secures booster
push rod to brake pedal (Fig. 1).
(9) Remove nuts attaching booster to the dash
panel (Fig. 2).(10) In engine compartment, slide booster studs
out of dash panel, tilt booster upward, and remove
booster from engine compartment.
INSTALLATION - RHD
(1) Align and position booster on the dash panel.
(2) Install booster mounting nuts. Tighten nuts
just enough to hold booster in place.
(3) Slide booster push rod onto the brake pedal.
Then secure push rod to pedal pin with retaining
clip.
NOTE: Lubricate the pedal pin with Mopar multi-
mileage grease before installation.
(4) Tighten booster mounting nuts to 39 N´m (29
ft. lbs.).
(5) Install the brake light switch.
(6) Install the knee blocker,(Refer to 23 - BODY/
INSTRUMENT PANEL/KNEE BLOCKER - INSTAL-
LATION).
(7) If original master cylinder is being installed,
check condition of seal at rear of master cylinder.
Replace seal if cut, or torn.
(8) Clean cylinder mounting surface of brake
booster. Use shop towel wetted with brake cleaner for
Fig. 1 BOOSTER PUSH ROD
1 - BRAKE PEDAL
2 - BOOSTER ROD
Fig. 2 BOOSTER MOUNTING
1 - BRAKE BOOSTER
KJBRAKES 5s - 1

this purpose. Dirt, grease, or similar materials will
prevent proper cylinder seating and could result in
vacuum leak.
(9) Align and install master cylinder on the
booster studs. Install mounting nuts and tighten to
17.5 N´m (155 in. lbs.).
(10) Connect vacuum hose to booster check valve.
(11) Remount the cruise control servo to the origi-
nal location. Tighten bracket mounting nuts to 17.5
N´m (155 in. lbs.).(12) Connect and secure the brake lines to HCU
and master cylinder. Start all brake line fittings by
hand to avoid cross threading.
(13) Connect the wire to fluid reservoir.
(14) Install the air box.
(15) Fill and bleed base brake system,(Refer to 5 -
BRAKES - STANDARD PROCEDURE).
(16) Verify proper brake operation before moving
vehicle.
5s - 2 BRAKESKJ
POWER BRAKE BOOSTER (Continued)

BRAKES
TABLE OF CONTENTS
page page
POWER BRAKE BOOSTER
REMOVAL - RHD........................1INSTALLATION - RHD.....................1
POWER BRAKE BOOSTER
REMOVAL - RHD
(1) Remove the air box (Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER ELEMENT -
REMOVAL).
(2) Relocate the cruise control servo to gain access
to the booster for removal.
(3) Remove the brake lines from the master cylin-
der.
(4) Remove the master cylinder (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/MASTER
CYLINDER - REMOVAL).
(5) Disconnect vacuum hose from booster check
valve.
(6) Remove knee blocker under the steering colum-
n,(Refer to 23 - BODY/INSTRUMENT PANEL/KNEE
BLOCKER - REMOVAL).
(7) Remove the brake light switch.(Refer to 8 -
ELECTRICAL/LAMPS/LIGHTING - EXTERIOR/
BRAKE LAMP SWITCH - REMOVAL)
(8) Remove retaining clip that secures booster
push rod to brake pedal (Fig. 1).
(9) Remove nuts attaching booster to the dash
panel (Fig. 2).(10) In engine compartment, slide booster studs
out of dash panel, tilt booster upward, and remove
booster from engine compartment.
INSTALLATION - RHD
(1) Align and position booster on the dash panel.
(2) Install booster mounting nuts. Tighten nuts
just enough to hold booster in place.
(3) Slide booster push rod onto the brake pedal.
Then secure push rod to pedal pin with retaining
clip.
NOTE: Lubricate the pedal pin with Mopar multi-
mileage grease before installation.
(4) Tighten booster mounting nuts to 39 N´m (29
ft. lbs.).
(5) Install the brake light switch.
(6) Install the knee blocker,(Refer to 23 - BODY/
INSTRUMENT PANEL/KNEE BLOCKER - INSTAL-
LATION).
(7) If original master cylinder is being installed,
check condition of seal at rear of master cylinder.
Replace seal if cut, or torn.
(8) Clean cylinder mounting surface of brake
booster. Use shop towel wetted with brake cleaner for
Fig. 1 BOOSTER PUSH ROD
1 - BRAKE PEDAL
2 - BOOSTER ROD
Fig. 2 BOOSTER MOUNTING
1 - BRAKE BOOSTER
KJBRAKES 5s - 1

this purpose. Dirt, grease, or similar materials will
prevent proper cylinder seating and could result in
vacuum leak.
(9) Align and install master cylinder on the
booster studs. Install mounting nuts and tighten to
17.5 N´m (155 in. lbs.).
(10) Connect vacuum hose to booster check valve.
(11) Remount the cruise control servo to the origi-
nal location. Tighten bracket mounting nuts to 17.5
N´m (155 in. lbs.).(12) Connect and secure the brake lines to HCU
and master cylinder. Start all brake line fittings by
hand to avoid cross threading.
(13) Connect the wire to fluid reservoir.
(14) Install the air box.
(15) Fill and bleed base brake system,(Refer to 5 -
BRAKES - STANDARD PROCEDURE).
(16) Verify proper brake operation before moving
vehicle.
5s - 2 BRAKESKJ
POWER BRAKE BOOSTER (Continued)

CLUTCH
TABLE OF CONTENTS
page page
CLUTCH
DESCRIPTION..........................1
OPERATION............................1
WARNING.............................2
DIAGNOSIS AND TESTING - CLUTCH........2
SPECIFICATIONS - CLUTCH...............5
CLUTCH DISC
REMOVAL.............................6
INSTALLATION..........................6
CLUTCH RELEASE BEARING
REMOVAL.............................6
INSTALLATION..........................6
FLYWHEEL
DESCRIPTION..........................7
OPERATION............................7
DIAGNOSIS AND TESTING - FLYWHEEL......8
PILOT BEARING
REMOVAL.............................8
INSTALLATION..........................8LINKAGE
REMOVAL.............................8
INSTALLATION..........................9
MASTER CYLINDER
INSPECTION...........................9
CLUTCH PEDAL
REMOVAL.............................10
INSTALLATION.........................10
CLUTCH SWITCH OVERRIDE RELAY
DESCRIPTION.........................10
OPERATION...........................10
REMOVAL.............................10
INSTALLATION.........................10
CLUTCH PEDAL POSITION SWITCH
DESCRIPTION.........................11
OPERATION...........................11
DIAGNOSIS AND TESTING - CLUTCH PEDAL
POSITION SWITCH....................11
CLUTCH
DESCRIPTION
The clutch mechanism consists of a flywheel, dry-
type disc, diaphragm style pressure plate and
hydraulic linkage. The flywheel is bolted to the rear
flange of the crankshaft. The clutch pressure plate is
bolted to the flywheel with the clutch disc between
these two components. The clutch system provides
the mechanical, link between the engine and the
transmission. The system is designed to transfer the
torque output of the engine, to the transmission
while isolating the transmission from the engine fir-
ing pulses to minimize concerns such as gear rattle.
OPERATION
The clutch operates with leverage, clamping force
and friction. The disc serves as the friction element,
the diaphragm spring and pressure plate provide the
clamping force. The clutch pedal, hydraulic linkage,
release lever and bearing provide the leverage.
The clutch master cylinder push rod is connected
to the clutch pedal. When the clutch pedal is
depressed, the slave cylinder is operated by the
clutch master cylinder mounted on the dash panel.
The release fork is actuated by the hydraulic slave
cylinder mounted on the transmission housing. The
release bearing is operated by a release fork pivoting
on a ball stud mounted in the transmission housing.
The release bearing then depresses the pressure
plate spring fingers, thereby releasing pressure on
the clutch disc and allowing the engine crankshaft to
spin independently of the transmission input shaft.
KJCLUTCH 6 - 1

WARNING
WARNING:: EXERCISE CARE WHEN SERVICING
CLUTCH COMPONENTS. FACTORY INSTALLED
CLUTCH DISCS DO NOT CONTAIN ASBESTOS
FIBERS. DUST AND DIRT ON CLUTCH PARTS MAY
CONTAIN ASBESTOS FIBERS FROM AFTERMAR-
KET COMPONENTS. BREATHING EXCESSIVE CON-
CENTRATIONS OF THESE FIBERS CAN CAUSE
SERIOUS BODILY HARM. WEAR A RESPIRATOR
DURING SERVICE AND NEVER CLEAN CLUTCH
COMPONENTS WITH COMPRESSED AIR OR WITH
A DRY BRUSH. EITHER CLEAN THE COMPONENTS
WITH A WATER DAMPENED RAGS OR USE A VAC-
UUM CLEANER SPECIFICALLY DESIGNED FOR
REMOVING ASBESTOS FIBERS AND DUST. DO NOT
CREATE DUST BY SANDING A CLUTCH DISC.
REPLACE THE DISC IF THE FRICTION MATERIAL IS
DAMAGED OR CONTAMINATED. DISPOSE OF ALL
DUST AND DIRT CONTAINING ASBESTOS FIBERS
IN SEALED BAGS OR CONTAINERS. THIS WILL
HELP MINIMIZE EXPOSURE TO YOURSELF AND TO
OTHERS. FOLLOW ALL RECOMMENDED SAFETY
PRACTICES PRESCRIBED BY THE OCCUPATIONAL
SAFETY AND HEALTH ADMINISTRATION (OSHA)
AND THE ENVIRONMENTAL SAFETY AGENCY
(EPA), FOR THE HANDLING AND DISPOSAL OF
PRODUCTS CONTAINING ASBESTOS.
DIAGNOSIS AND TESTING - CLUTCH
Drive the vehicle at normal speeds. Shift the trans-
mission through all gear ranges and observe clutch
action. If the clutch chatters, grabs, slips or does not
release properly, remove and inspect the clutch com-
ponents. If the problem is noise or hard shifting, fur-
ther diagnosis may be needed as the transmission or
another driveline component may be at fault.
NOTE: Vehicles equipped with a Dual Mass Fly-
wheel may produce a rattle when the engine is shut
off. This noise is considered normal.
CLUTCH CONTAMINATION
Fluid contamination is a frequent cause of clutch
malfunctions. Oil, water or clutch fluid on the clutch
disc and pressure plate surfaces will cause chatter,
slip and grab. Inspect components for oil, hydraulic
fluid or water/road splash contamination.
Oil contamination indicates a leak at either the
rear main seal or transmission input shaft. Clutch
fluid leaks are usually from damaged slave cylinder
push rod seals. Heat buildup caused by slippage
between the pressure plate, disc and flywheel can
bake the oil residue onto the components. The glaze-
like residue ranges in color from amber to black.Road splash contamination is dirt/water entering
the clutch housing due to loose bolts, housing cracks.
Driving through deep water puddles can force water/
road splash into the housing through such openings.
IMPROPER RELEASE OR CLUTCH ENGAGEMENT
Clutch release or engagement problems are caused
by wear or damage clutch components. A visual
inspection of the release components will usually
reveal the problem part.
Release problems can result in hard shifting and
noise. Look for leaks at the clutch cylinders and
interconnecting line and loose slave cylinder bolts.
Also worn/loose release fork, pivot stud, clutch disc,
pressure plate or release bearing.
Engagement problems can result in slip, chatter/
shudder and noisy operation. The causes may be
clutch disc contamination, wear, distortion or fly-
wheel damage. Visually inspect to determine the
actual cause of the problem.
CLUTCH MISALIGNMENT
Clutch components must be in proper alignment
with the crankshaft and transmission input shaft.
Misalignment caused by excessive runout or warpage
of any clutch component will cause grab, chatter and
improper clutch release.
PRESSURE PLATE AND DISC RUNOUT
Check the clutch disc before installation. Axial
(face) runout of anewdisc should not exceed 0.50
mm (0.020 in.). Measure runout about 6 mm (1/4 in.)
from the outer edge of the disc facing. Obtain
another disc if runout is excessive.
Check condition of the clutch before installation. A
warped cover or diaphragm spring will cause grab
and incomplete release or engagement. Be careful
when handling the cover and disc. Impact can distort
the cover, diaphragm spring, release fingers and the
hub of the clutch disc.
Use an alignment tool when positioning the disc on
the flywheel. The tool prevents accidental misalign-
ment which could result in cover distortion and disc
damage.
A frequent cause of clutch cover distortion (and
consequent misalignment) is improper bolt tighten-
ing.
FLYWHEEL RUNOUT
Check flywheel runout whenever misalignment is
suspected. Flywheel runout should not exceed 0.08
mm (0.003 in.). Measure runout at the outer edge of
the flywheel face with a dial indicator. Mount the
indicator on a stud installed in place of one of the fly-
wheel bolts.
6 - 2 CLUTCHKJ
CLUTCH (Continued)

Common causes of runout are:
²heat warpage
²improper machining
²incorrect bolt tightening
²improper seating on crankshaft flange shoulder
²foreign material on crankshaft flange
Flywheel machining is not recommended. The fly-
wheel clutch surface is machined to a unique contour
and machining will negate this feature. Minor fly-
wheel scoring can be cleaned up by hand with 180
grit emery or with surface grinding equipment.
Remove only enough material to reduce scoring
(approximately 0.001 - 0.003 in.). Heavy stock
removal isnot recommended.Replace the flywheel
if scoring is severe and deeper than 0.076 mm (0.003
in.). Excessive stock removal can result in flywheel
cracking or warpage after installation; it can alsoweaken the flywheel and interfere with proper clutch
release.
Clean the crankshaft flange before mounting the
flywheel. Dirt and grease on the flange surface may
cock the flywheel causing excessive runout. Use new
bolts when remounting a flywheel and secure the
bolts with Mopar Lock And Seal or equivalent.
Tighten flywheel bolts to specified torque only. Over-
tightening can distort the flywheel hub causing
runout.
DIAGNOSIS CHART
The diagnosis charts Diagnosis Chart describe
common clutch problems, causes and correction. Con-
ditions, causes and corrective action are outlined in
the indicated columns.
DIAGNOSIS CHART
CONDITION POSSIBLE CAUSES CORRECTION
Disc facing worn out 1. Normal wear. 1. Replace cover and disc.
2. Driver frequently rides (slips) the
clutch. Results in rapid overheating
and wear.2. Replace cover and disc.
3. Insufficient clutch cover
diaphragm spring tension.3. Replace cover and disc.
Clutch disc facing contaminated with
oil, grease, or clutch fluid.1. Leak at rear main engine seal or
transmission input shaft seal.1. Replace appropriate seal.
2. Excessive amount of grease
applied to the input shaft splines.2. Remove grease and apply the
correct amount of grease.
3. Road splash, water entering
housing.3. Replace clutch disc. Clean clutch
cover and reuse if in good condition.
4. Slave cylinder leaking. 4. Replace hydraulic clutch linkage.
Clutch is running partially
disengaged.1. Release bearing sticking or
binding and does not return to the
normal running position.1. Verify failure. Replace the release
bearing and transmission front
bearing retainer as necessary.
Flywheel below minimum thickness
specification.1. Improper flywheel machining.
Flywheel has excessive taper or
excessive material removal.1. Replace flywheel.
Clutch disc, cover and/or diaphragm
spring warped or distorted.1. Rough handling. Impact bent
cover, spring, or disc.1. Replace disc or cover as
necessary.
2. Improper bolt tightening
procedure.2. Tighten clutch cover using proper
procedure.
KJCLUTCH 6 - 3
CLUTCH (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
Facing on flywheel side of disc torn,
gouged, or worn.1. Flywheel surface scored or
nicked.2. Correct surface condition if
possible. Replace flywheel and disc
as necessary.
2. Clutch disc sticking or binding on
transmission input shaft.2. Lubricate splines with high
temperature graese.
Clutch disc facing burnt. Flywheel
and cover pressure plate surfaces
heavily glazed.1. Frequent operation under high
loads or hard acceleration
conditions.1. Correct condition of flywheel and
pressure plate surface. Replace
clutch cover and disc. Alert driver to
problem cause.
2. Driver frequently rides (slips)
clutch. Results in rapid wear and
overheating of disc and cover.2. Correct condition of flywheel and
pressure plate surface. Replace
clutch cover and disc. Alert driver to
problem cause.
Clutch disc binds on input shaft
splines.1. Clutch disc hub splines damaged
during installation.1. Clean, smooth, and lubricate hub
splines if possible. Replace disc if
necessary.
2. Input shaft splines rough,
damaged, or corroded.2. Clean, smooth, and lubricate
shaft splines if possible. Replace
input shaft if necessary.
Clutch disc rusted to flywheel and/or
pressure plate.1. Clutch not used for and extended
period of time (e.g. long term
vehicle storage).1. Sand rusted surfaces with 180
grit sanding paper. Replace clutch
cover and flywheel if necessary.
Pilot bearing seized, loose, or rollers
are worn.1. Bearing cocked during
installation.1. Install and lubricate a new
bearing.
2. Bearing defective. 2. Install and lubricate a new
bearing.
3. Bearing not lubricated. 3. Install and lubricate a new
bearing.
4. Clutch misalignment. 4. Inspect clutch and correct as
necessary. Install and lubricate a
new bearing.
Clutch will not disengage properly. 1. Low clutch fluid level. 1. Replace hydraulic linkage
assembly.
2. Clutch cover loose. 2. Follow proper bolt tightening
procedure.
3. Clutch disc bent or distorted. 3. Replace clutch disc.
4. Clutch cover diaphragm spring
bent or warped.4. Replace clutch cover.
5. Clutch disc installed backwards. 5. Remove and install clutch disc
correctly.
6. Release fork bent or fork pivot
loose or damaged.6. Replace fork or pivot as
necessary.
7. Clutch master or slave cylinder
failure.7. Replace hydraulic linkage
assembly.
6 - 4 CLUTCHKJ
CLUTCH (Continued)