1995 JEEP YJ service

(2) Disconnect release bearing from release lever
and remove bearing (Fig. 6).
(3) Inspect bearing slide surface of transmission
front bearing retainer. Replace retainer if slide sur-
face is scored, worn, or cracked.
(4) Inspect release fork and fork pivot. Be sure
pivot is secure and in good condition. Be sure fork is
not distorted or worn. Replace release fork retainer
spring if bent or damaged in any way.
(5) Lubricate crankshaft pilot bearing with Mopar
high temperature bearing grease. Apply grease to
end of long shank, small diameter flat blade screw-
driver. Then insert tool through clutch disc hub to
reach bearing.
(6) Lubricate input shaft splines, bearing retainer
slide surface, fork pivot and release fork pivot surface
with Mopar high temperature grease.
(7) Install new release bearing. Be sure bearing is
properly secured to release fork.
(8) Install transmission as described in Group 21.
PILOT BEARING REPLACEMENT
(1) Remove transmission. Refer to Group 21 for
procedure.
(2) Remove clutch cover and disc.
(3) Remove pilot bearing. Use internal (blind hole)
puller such those as supplied in Snap On Tool Set
CG40CB to remove bearing.
(4) Lubricate new bearing with Mopar high tem-
perature bearing grease.
(5) Start new bearing into crankshaft by hand.
Then seat bearing with clutch alignment tool (Fig. 7).(6) Lightly scuff sand flywheel surface with 180
grit emery cloth. Then clean surface with wax and
grease remover.
(7) Install clutch disc and cover as described in
this section.
Fig. 5 Manual Transmission Mounting (2.5L)
Fig. 6 Release Bearing Attachment
6 - 12 CLUTCH SERVICEJ

(8) Install transmission. Refer to Group 21 for pro-
cedure.
CLUTCH HOUSING REPLACEMENT
The clutch housing is removable and can be re-
placed when the transmission is out of the vehicle.
The bolts attaching the housing to the transmission
case are located inside the housing (Fig. 8). Recom-
mended tightening torque for the clutch housing-to-
transmission bolts is 38 Nzm (28 ft. lbs.).
Be sure the transmission and housing mating
surfaces are clean before installing an original,
or replacement clutch housing. Dirt/foreign ma-
terial trapped between the housing and trans-
mission will cause misalignment. If
misalignment is severe enough, the result will
be clutch drag, incomplete release and hard
shifting.
CLUTCH HYDRAULIC LINKAGE REMOVAL
The clutch master cylinder, slave cylinder
and connecting line are serviced as an assem-
bly only. The linkage components cannot be
overhauled or serviced separately. The cylin-
ders and connecting line are sealed units. Also
note that removal/installation procedures forright and left hand drive models are basically
the same. Only master cylinder location is dif-
ferent.
(1) Raise vehicle.
(2) Remove fasteners attaching slave cylinder to
clutch housing.
(3) Remove slave cylinder from clutch housing (Fig.
9).
(4) Disengage clutch fluid line from body clips.
(5) Lower vehicle.
(6) Verify that cap on clutch master cylinder reser-
voir is tight. This is necessary to avoid undue spill-
age during removal.
(7) Remove clutch master cylinder attaching nuts.
Note that one nut is accessible from engine compart-
ment and one nut is accessible from under instru-
ment panel (Figs. 10 and 11).
(8) Remove clip securing clutch master cylinder
push rod to pedal and slide push rod off pedal pin.
(9) Disconnect clutch pedal position switch wires.
(10) If pedal pin is equipped with bushing, inspect
condition of bushing and replace it if worn or dam-
aged.
(11) Remove clutch hydraulic linkage through en-
gine compartment.
Fig. 8 Clutch Housing AttachmentFig. 7 Pilot Bearing Installation
JCLUTCH SERVICE 6 - 13

CLUTCH HYDRAULIC LINKAGE INSTALLATION
(1) Be sure reservoir cover on clutch master cylin-
der is tight to avoid spills.
(2) Position clutch linkage components in vehicle.
Work connecting line and slave cylinder downward
past engine and adjacent to clutch housing.
(3) Position clutch master cylinder on dash panel
(Fig. 12).
(4) Attach clutch master cylinder push rod to pin
on clutch pedal. Secure rod with new clip if neces-
sary.
(5) Install and tighten clutch master cylinder at-
taching nuts to 23-34 Nzm (200-300 in. lbs.) torque.
(6) Raise vehicle.
(7) Insert slave cylinder push rod through clutch
housing opening and into release lever. Be sure cap
on end of rod is securely engaged in lever. Check this
before installing cylinder attaching nuts.
(8) Install and tighten slave cylinder attaching
nuts to 23-34 Nzm (200-300 in. lbs.) torque.
(9) Secure clutch fluid line in body clips.
(10) Lower vehicle.
(11) Connect clutch pedal position switch wires.
CLUTCH FLUID LEVEL
The clutch fluid reservoir, master cylinder, slave
cylinder and fluid lines are prefilled with fluid at the
factory during assembly operations.
The hydraulic system should not require additional
fluid under normal circumstances. In fact,the reser-
voir fluid level will actually increase as normal
clutch wear occurs. For this reason, it is impor-
tant to avoid overfilling, or removing fluid from
the reservoir.
Fig. 9 Slave Cylinder Attachment
Fig. 10 Clutch Master Cylinder And Push Rod
Attachment (Left Hand Drive Models)
Fig. 11 Clutch Master Cylinder Location (Right Hand
Drive Models)
Fig. 12 Clutch Master Cylinder Mounting (Typical)
6 - 14 CLUTCH SERVICEJ

If inspection or diagnosis indicates additional fluid
may be needed, use Mopar brake fluid, or an equiv-
alent meeting standards SAE J1703 and DOT 3. Do
not use any other type of fluid.
Clutch fluid level is checked at the master cylinder
reservoir (Fig. 13). An indicator ring is provided ei-
ther on the side, or interior rim of the reservoir (Fig.
14).
Be sure to wipe the reservoir and cover clean be-
fore removing the cover. This will avoid having dirt
or foreign material fall into the reservoir during a
fluid level check.
CLUTCH PEDAL REMOVAL
(1) Remove instrument panel lower trim cover for
extra working clearance.(2) Disconnect clutch pedal position switch wires.
(3) Remove retainer clip that attaches clutch mas-
ter cylinder push rod to pedal.
(4) On YJ, remove retaining ring securing pedal to
pivot shaft (Fig. 15). On XJ, remove nut securing
pedal to pivot shaft (Fig. 16).
(5) Move pedal pivot shaft to right and slide pedal
off shaft.
CLUTCH PEDAL INSTALLATION
(1) Lubricate clutch pedal pivot shaft and pedal
bushings or sleeve with Mopar multi-mileage grease.
(2) Position pedal on pivot shaft and through
brace. Secure pedal with washer and retaining ring
on YJ, or with washer and nut on XJ.
Fig. 13 Clutch Master Cylinder Reservoir And CapFig. 14 Reservoir Fluid Level Indicator Ring
Fig. 15 Clutch Pedal Mounting (YJ)
JCLUTCH SERVICE 6 - 15

(3) Install clutch master cylinder push rod on
pedal. Secure rod with washer(s) and new cotter pin.
(4) Connect clutch pedal position switch wires.
(5) Install instrument panel lower trim cover, if re-
moved.
FLYWHEEL SERVICE
Inspect the flywheel whenever the clutch disc,
cover and housing are removed for service. Check
condition of the flywheel face, hub, ring gear teeth,
and flywheel bolts.
Minor scratches, burrs, or glazing on the flywheel
face can be reduced with 180 grit emery cloth. How-
ever, the flywheel should be replaced if the disc con-
tact surface is severely scored, heat checked, cracked,
or obviously worn.
Flywheel machining is not recommended. The fly-
wheel surface is manufactured with a unique contour
that would be negated by machining. However,
cleanup of minor flywheel scoring can be performed
by hand with 180 grit emery, or with surface grind-
ing equipment. Replace the flywheel if scoring is
deeper than 0.0762 mm (0.003 in.).
Heavy stock removal by grinding isnot recom-
mended.Excessive stock removal can result in fly-
wheel cracking or warpage after installation. It can
also weaken the flywheel and interfere with proper
clutch release.
Check flywheel runout if misalignment is sus-
pected. Runout should not exceed 0.08 mm (0.003
in.). Measure runout at the outer edge of the fly-
wheel face with a dial indicator. Mount the dial indi-
cator on a stud installed in place of one of the
flywheel attaching bolts.
Clean the crankshaft flange before mounting the
flywheel. Dirt and grease on the flange surface may
cock the flywheel causing excessive runout.
Check condition of the flywheel hub and attaching
bolts. Replace the flywheel if the hub exhibits cracks
in the area of the attaching bolt holes.
Install new attaching bolts whenever the flywheelis replaced and use Mopar Lock N' Seal, or Loctite
242 on the replacement bolt threads.
Recommended flywheel bolt torques are:
²142 Nzm (105 ft. lbs.) for 6-cylinder flywheels
²68 Nzm (50 ft. lbs.) plus an additional turn of 60É
for 4-cylinder flywheels
Inspect the teeth on the starter ring gear.If the
teeth are worn or damaged, the flywheel should
be replaced as an assembly. This is the recom-
mended and preferred method of repair.
In cases where a new flywheel is not readily avail-
able, a replacement ring gear can be installed. How-
ever, the following precautions must be observed to
avoid damaging the flywheel and replacement gear.
(a) Mark position of the old gear for alignment
reference on the flywheel. Use a scriber for this
purpose.
(b) Wear protective goggles or approved safety
glasses. Also wear heat resistent gloves when han-
dling a heated ring gear.
(c) Remove the old gear by cutting most of the
way through it (at one point) with an abrasive cut-
off wheel. Then complete removal with a cold chisel
or punch.
(d) The ring gear is a shrink fit on the flywheel.
This means the gear must be expanded by heating
in order to install it.The method of heating and
expanding the gear is extremely important.
Every surface of the gear must be heated at the
same time to produce uniform expansion. An oven
or similar enclosed heating device must be used.
Temperature required for uniform expansion is ap-
proximately 375É F.
CAUTION: Do not use an oxy/acetylene torch to re-
move the old gear, or to heat and expand a new
gear. The high temperature of the torch flame can
cause localized heating that will damage the fly-
wheel. In addition, using the torch to heat a replace-
ment gear will cause uneven heating and
expansion. The torch flame can also anneal the
gear teeth resulting in rapid wear and damage after
installation.
(e) The heated gear must be installed evenly to
avoid misalignment or distortion. A shop press and
suitable press plates should be used to install the
gear if at all possible.
(f) Be sure to wear eye and hand protection.
Heat resistent gloves and safety goggles are needed
for personal safety. Also use metal tongs, vise grips,
or similar tools to position the gear as necessary
for installation.
(g) Allow the flywheel and ring gear to cool down
before installation. Set the assembly on a work-
bench and let it cool in normal shop air.
Fig. 16 Clutch Pedal Mounting (XJ)
6 - 16 CLUTCH SERVICEJ

CAUTION: Do not use water, or compressed air to
cool the flywheel. The rapid cooling produced by
water or compressed air can distort, or crack the
gear and flywheel.TORQUE SPECIFICATIONS
JCLUTCH SERVICE 6 - 17

COOLING SYSTEM
CONTENTS
page page
DIAGNOSIS............................. 4
ENGINE ACCESSORY DRIVE BELTS......... 38
ENGINE BLOCK HEATER.................. 44GENERAL INFORMATION.................. 1
SERVICE PROCEDURES.................. 13
SPECIFICATIONS........................ 45
GENERAL INFORMATION
Throughout this group, references are made to par-
ticular vehicle models by alphabetical designation
(XJ or YJ) or by the particular vehicle nameplate. A
chart showing a breakdown of alphabetical designa-
tions is included in the Introduction section at the
beginning of this manual.
COOLING SYSTEM
The cooling system regulates engine operating tem-
perature. It allows the engine to reach normal oper-
ating temperature as quickly as possible, maintains
normal operating temperature and prevents over-
heating.
The cooling system also provides a means of heat-
ing the passenger compartment and cooling the auto-
matic transmission fluid (if equipped). The cooling
system is pressurized and uses a centrifugal water
pump to circulate coolant throughout the system.
An optional factory installed heavy duty cooling
package is available on most models. The package
consists of a radiator that has an increased number
of cooling fins. XJ models equipped with a 4.0L 6-cyl-inder engine and heavy duty cooling and/or air con-
ditioning also have an auxiliary electric cooling fan.
COOLING SYSTEM COMPONENTS
The cooling system consists of:
²A radiator
²Cooling fan (mechanical and/or electrical)
²Thermal viscous fan drive
²Fan shroud
²Radiator pressure cap
²Thermostat
²Coolant reserve/overflow system
²Transmission oil cooler (if equipped with an auto-
matic transmission)
²Coolant
²Water pump
²Hoses and hose clamps
SYSTEM COOLANT ROUTING
For cooling system flow routings, refer to Figs. 1, 2,
3or4.
JCOOLING SYSTEM 7 - 1

DIAGNOSIS
INDEX
page page
DRB Scan Tool............................ 5
On-Board Diagnostics (OBD).................. 4Preliminary Checks......................... 5
ON-BOARD DIAGNOSTICS (OBD)
FOR CERTAIN COOLING SYSTEM
COMPONENTS
The powertrain control module (PCM) has been
programmed to monitor the certain following cooling
system components:
²If the engine has remained cool for too long a pe-
riod, such as with a stuck open thermostat, a Diag-
nostic Trouble Code (DTC) number 17 can be
observed at the malfunction indicator lamp. This
lamp is displayed on the instrument panel as the
CHECK ENGINE lamp (Figs. 5 or 6).
²If an open or shorted condition has developed in
the relay circuit controlling the electric radiator fan,
a Diagnostic Trouble Code (DTC) number 35 can be
observed at the CHECK ENGINE lamp (XJ models
only).
If the problem is sensed in a monitored circuit of-
ten enough to indicate an actual problem, a DTC is
stored. The DTC will be stored in the PCM memory
for eventual display to the service technician. If theproblem is repaired or ceases to exist, the PCM can-
cels the DTC after 51 engine starts.
Certain criteria must be met for a DTC to be en-
tered into PCM memory. The criteria may be a spe-
cific range of engine rpm, engine temperature and/or
input voltage to the PCM.
A DTC indicates that the PCM has recognized an
abnormal signal in a circuit or the system. A DTC
may indicate the result of a failure, but never iden-
tify the failed component directly.
It is possible that a DTC for a monitored circuit
may not be entered into memory even though a mal-
function has occurred. Refer to On-Board Diagnostics
(OBD) in Group 14, Fuel Systems for additional DTC
information.
ACCESSING DIAGNOSTIC TROUBLE CODES
A stored Diagnostic Trouble Code (DTC) can be dis-
played by cycling the ignition key On-Off-On-Off-On
within three seconds and observing the malfunction
indicator lamp. This lamp is displayed on the instru-
ment panel as the CHECK ENGINE lamp (Figs. 5 or
6).
They can also be displayed through the use of the
Diagnostic Readout Box (DRB) scan tool. The DRB
connects to the data link connector in the engine
compartment (Figs. 7 or 8). For operation of the
DRB, refer to the appropriate Powertrain Diagnostic
Procedures service manual.
Fig. 5 Check Engine LampÐXJ ModelsÐTypical
Fig. 6 Check Engine LampÐYJ ModelsÐTypical
7 - 4 COOLING SYSTEM DIAGNOSISJ