1994 JEEP CHEROKEE tow

(8) Check crankshaft end play. Crankshaft end
play is controlled by the thrust bearing which is
flange and installed at the No.2 main bearing posi-
tion.
(a) Attach a magnetic base dial indicator to the
cylinder block at either the front or rear of the en-
gine.
(b) Position the dial indicator rod so that it is
parallel to the center line of the crankshaft.
(c) Pry the crankshaft forward, position the dial
indicator to zero.
(d) Pry the crankshaft forward and backward.
Note the dial indicator readings. End play is the
difference between the high and low measurements
(Fig. 6). Correct end play is 0.038-0.165 mm
(0.0015-0.0065 inch). The desired specifications are
0.051-0.064 mm (0.002-0.0025 inch).
(e) If end play is not within specification, inspect
crankshaft thrust faces for wear. If no wear is ap-
parent, replace the thrust bearing and measure end
play. If end play is still not within specification, re-
place the crankshaft.
If the crankshaft was removed, install the crank-
shaft into the cylinder block (refer to Cylinder Block -
Assemble).
(9) Install the oil pan.
(10) Install the drain plug. Tighten the plug to 34
Nzm (25 ft. lbs.) torque.
(11) Lower the vehicle.
(12) Install the spark plugs. Tighten the plugs to
37 Nzm (27 ft. lbs.) torque.
(13) Fill the oil pan with engine oil to the full
mark on the dipstick level.
(14) Connect negative cable to battery.
REAR MAIN OIL SEALS
The crankshaft rear main bearing oil seal consists
of two half pieces of viton with a single lip that ef-fectively seals the rear of the crankshaft. Replace the
upper and lower seal halves as a unit to ensure leak-
free operation.
REMOVAL
(1) Remove the engine flywheel or converter drive
plate.
(2) Remove the oil pan.
(3) Remove the rear main bearing cap (No.7).
(4) Push the upper seal out of the groove. Ensure
that the crankshaft and seal groove are not damaged.
(5) Remove the lower half of the seal from the
bearing cap.
INSTALLATION
(1) Wipe the seal surface area of the crankshaft
until it is clean.
(2) Apply a thin coat of engine oil.
(3) Coat the lip of the seal with engine oil.
(4) Carefully position the upper seal into the
groove in the cylinder block. The lip of the seal faces
toward the front of the engine.
(5) Place the lower half of the seal into bearing cap
No.7 (Fig. 7).
(6) Coat the outer curved surface of the lower seal
with soap and the lip of the seal with engine oil (Fig.
7).
(7) Position the lower seal into the bearing cap re-
cess and seat it firmly. Be sure the seal is flush with
the cylinder block pan rail.
(8) Apply Loctite 515, or equivalent on the rear
bearing cap (Fig. 8). The bead should be 3 mm (0.125
in) thick. DO NOT apply Loctite 515, or equivalent
to the lip of the seal.
Fig. 7 Rear Main Bearing Oil Seal
Fig. 6 Crankshaft End Play Measurement
9 - 84 4.0L ENGINEJ

XJ BUMPERS
INDEX
page page
Front Bumper............................ 3
Front Tow Hooks......................... 5Rear Bumper............................ 6
FRONT BUMPER
REMOVAL/DISASSEMBLY
(1) The bumper guards, end caps and tow hooks
can be removed from XJ front bumpers with the
bumper attached to the vehicle. Do not remove the
bumper from the vehicle if only these components re-
quire service.
If equipped with a brush guard, refer to the
Brush Guard Removal within Group 23ÐBody
Components.
(2) If equipped, disconnect the fog lamp wire har-
ness connectors (Fig. 1).
(3) Disconnect the vacuum reservoir tube harness
connectors (Figs. 2 and 3).
(4) If equipped, remove the locknuts and Torx-head
bolts that attach the tow hook straps (Fig. 4) to the
underbody sillmember.
The retaining screws and the steering gear
skid plate must be removed before the left strap
can be removed from the sillmember.
(5) Detach the tow hook straps from the sillmem-
ber.
(6) Support the bumper.
(7) Remove the bolts that attach the bumper sup-
port brackets to the right and left sillmembers (Fig.
5).
(8) Remove the support and the bumper from the
vehicle. 5).(9) If equipped, remove the nuts and bolts that at-
tach the tow hooks to the bumper support brackets.
(10) Remove the support brackets (Fig. 6), bumper
guards (Fig. 7) and caps (Fig. 8) from the bumper
rail.
(11) Remove the license plate bracket (Fig. 9), if
equipped, from the bumper rail.
Fig. 1 Fog Lamp Wire Harness Connector
Fig. 2 Vacuum ReservoirÐLeft Side
Fig. 3 Vacuum ReservoirÐRight Side With Speed
Control Only
JFRAME AND BUMPERS 13 - 3

(12) If equipped, remove the fog lamps (Fig. 10)
from the bumper rail.
(13) If necessary, remove the vacuum reservoir(s)
from the bumper rail.
(14) If necessary, remove the sill crossmember re-
inforcement brackets from the sillmembers.
ASSEMBLY/INSTALLATION
(1) If removed, install the sill crossmember rein-
forcement brackets on the sillmembers (Fig. 11).
Tighten bolts to 56 Nzm (41 ft-lbs) torque.
(2) If equipped, install the bumper support brack-
Fig. 4 Tow Hook & StrapÐXJ Vehicles
Fig. 5 Front Bumper Removal/Installation
Fig. 6 Bumper Support Bracket Removal/Installation
Fig. 7 Bumper Guard Removal/Installation
Fig. 8 Bumper End Cap Removal/Installation
13 - 4 FRAME AND BUMPERSJ

ets and bumper guards on the bumper rail. Tighten
hardware in the sequence indicated in Figure 7.
Tighten the locknuts with 20 Nzm (15 ft-lbs) torque.
Tighten bolts to 56 Nzm (41 ft-lbs) torque.(3) If not equipped with bumper guards, install the
bumper support brackets on the bumper rail. Tighten
bolts to 56 Nzm (41 ft-lbs) torque.
(4) If equipped with tow hooks, install the bolts
and nuts that attach them to the bumper support
brackets. Tighten nuts with 100 Nzm (74 ft-lbs)
torque.
(5) Install the bumper end caps on the bumper rail
(Fig. 8). Tighten nuts with 8 Nzm (72 in-lbs) torque.
(6) Install the license plate bracket on the bumper
rail. Tighten the nuts securely.
(7) If equipped, install the fog lamps on the
bumper rail. Tighten the nuts securely.
(8) If removed, install the vacuum reservoir(s) on
the bumper rail. Tighten the retaining screws and
bolts to 8 Nzm (72 in-lbs) torque.
(9) Position and support the bumper at the front of
the vehicle.
(10) Attach the bumper support brackets to the
right and left sillmembers and reinforcement brack-
ets. Tighten screws and bolts to 56 Nzm (41 ft-lbs)
torque.
(11) If equipped, install the Torx-head bolts and
locknuts that attach the tow hook straps to the un-
derbody sillmember. Tighten locknuts with 30 Nzm
(22 ft-lbs) torque.
Install the steering gear skid plate and screws
after the left tow hook strap has been installed.
(12) If equipped, connect the fog lamp wire harness
connectors.
(13) Connect the vacuum reservoir tube harness
connectors.
(14) Remove the bumper support.
FRONT TOW HOOKS
If a tow hook must be replaced or removed only for
service access, remove the nuts and bolts that attach
it to the bumper support bracket. When installing a
tow hook, tighten nuts with 100 Nzm (74 ft-lbs)
torque.
If a tow hook/bumper support bracket must be re-
placed, refer to the following removal and installa-
tion procedures.
REMOVAL
If equipped with a brush guard, refer to the
Brush Guard Removal within Group 23ÐBody
Components.
(1) If equipped, disconnect the fog lamp wire har-
ness connectors.
(2) Disconnect the vacuum reservoir tube harness
connectors.
(3) Support the bumper.
(4) Remove the bolts that attach the bumper sup-
port brackets to the right and left sillmembers.
(5) Remove the locknuts and Torx-head bolts that
attach the tow hook straps to the underbody sillmem-
ber.
Fig. 9 Bumper License Plate Bracket Removal/
Installation
Fig. 10 Fog Lamp
Fig. 11 Reinforcement Brackets
JFRAME AND BUMPERS 13 - 5

The retaining screws and the steering gear
skid plate must be removed before the left strap
can be removed from the sillmember.
(6) Detach the tow hook straps from the sillmem-
ber.
(7) Remove the support and the bumper from the
vehicle.
(8) Remove the nuts and bolts that attach the tow
hooks to the bumper support brackets.
(9) Remove the tow hook from the bumper support
bracket (Fig. 4).
(10) Remove the support bracket from the bumper
rail.
INSTALLATION
(1) If equipped, install the bumper guard and
bumper support bracket on the bumper rail. Tighten
the retaining hardware in the sequence indicated in
Figure 7. Tighten locknuts to 20 Nzm (15 ft-lbs)
torque. Tighten bolts to 56 Nzm (41 ft-lbs) torque.
(2) If not equipped with bumper guards, install the
bumper support bracket on the bumper rail. Tighten
bolts to 56 Nzm (41 ft-lbs) torque.
(3) Position the tow hook at the support bracket.
Install the bolts and nuts that attach tow hook to the
bumper support bracket. (Fig. 4). Tighten nuts to 100
Nzm (74 ft-lbs) torque.
(4) Position and support the bumper at the front of
the vehicle.
(5) Attach the bumper support brackets to the
right and left sillmembers and reinforcement brack-
ets. Tighten screws and bolts to 56 Nzm (41 ft-lbs)
torque.
(6) If equipped, install the Torx-head bolts and
locknuts that attach the tow hook straps to the un-
derbody sillmember. Tighten locknuts to 30 Nzm (22
ft-lbs) torque.
Install the steering gear skid plate and screws
after the left tow hook strap has been installed.
(7) If equipped, connect the fog lamp wire harness
connectors. Connect the vacuum reservoir tube har-
ness connectors.
(8) Remove the bumper support.
REAR BUMPER
REMOVAL
(1) For vehicles equipped with a trailer hitch, re-
move the hitch before removing the bumper. If nec-
essary, refer to the removal procedure within Group
23ÐBody Components.
(2) Raise and support the rear of the vehicle.
(3) Support the bumper.
(4) Remove the bolts that attach the bumper sup-
port brackets to the sill crossmember (Fig. 12).
(5) Remove the support and the rear bumper from
the vehicle.(6) Remove the bumper support brackets and
splash shield the bumper, if necessary (Fig. 13).
(7) Remove the bumper end caps (Fig. 14) and
bumper guards from the bumper (Fig. 15), if neces-
sary.
INSTALLATION
(1) As applicable, install the splash shield and
bumper support brackets, the bumper end caps and
the bumper guards.
(2) Tighten the bumper support bolts to 56 Nzm
(41 ft-lbs).
(3) Tighten the nuts in the sequence depicted in
Figure 14. Tighten the bumper end cap plate bolt
nuts to 22 Nzm (16 ft-lbs) torque. Tighten the lower
bolt nuts to 8 Nzm (6 ft-lbs) torque.
(4) If applicable, tighten the bumper guard bolts/
nuts to 56 Nzm (41 ft-lbs).
(5) Position and support the bumper with the
bracket holes aligned with the sill crossmember
Fig. 12 Rear Bumper Removal/InstallationÐXJ
Vehicles
Fig. 13 Bumper Bracket & Splash Shield Removal/
InstallationÐXJ Vehicles
13 - 6 FRAME AND BUMPERSJ

YJ BUMPERS AND FRAME ATTACHED COMPONENTS
INDEX
page page
Generator Splash Shield................... 14
Body.................................. 18
Engine Front Support Cushion............... 15
Frame Crossmember Cover................. 14
Front Bumper........................... 14
Fuel and Brake Fluid Tube Retainer Clip....... 16
Fuel Filter Shield and Bracket............... 17
Fuel Tank Skid Plate...................... 16Muffler and Tailpipe Heat Shields............ 17
Muffler/Tailpipe Hanger Bracket.............. 16
Rear Bumper............................ 18
Rear Jounce Bumper..................... 18
Service Information....................... 14
Tow Hooks............................. 14
Transfer Case Skid Plate.................. 15
SERVICE INFORMATION
In some cases, components in the following proce-
dures either support, or are hidden by other compo-
nents.
FRONT BUMPER
The YJ front bumper is a one-piece rail (Fig. 1). A
front crossmember cover (Fig. 1) is also installed on
all YJ vehicles.
BUMPER REMOVAL
(1) Disconnect and remove the fog lamps, if
equipped.
(2) Remove the nuts and bolts that retain the
bumper extensions to the bumper rail and remove
the extensions.
(3) Remove the nuts and bolts that attach the
bumper rail/tow hooks to the frame rails.(4) Remove the bumper rail from the frame rails.
BUMPER INSTALLATION
(1) Position the front bumper on the frame rails.
(2) Install the bolts and attach the front bumper
rail (and tow hooks, if equipped) to the frame rails.
(3) Tighten the bolts to 102 Nzm (75 ft-lbs) torque.
(4) Position the bumper extensions on the bumper
rail and install the retaining bolts.
(5) Tighten the bolts to 104 Nzm (77 ft-lbs) torque.
(6) Install the fog lamps, if equipped.
FRAME CROSSMEMBER COVER
REMOVAL
(1) Remove the screws that attach the crossmem-
ber cover and support to the frame rails.
(2) Remove the crossmember cover and support
from the frame rails.
INSTALLATION
(1) Position the support and crossmember cover on
the frame rails.
(2) Install the attaching screws.
(3) Tighten the screws to 8 Nzm (72 in-lbs) torque.
TOW HOOKS
REMOVAL
(1) Remove the two bolts that attach the tow hook
to the bumper rail and to the frame rail.
(2) Remove the tow hook.
INSTALLATION
(1) Position the tow hook on the bumper rail and
frame rail.
(2) Install the attaching bolts.
(3) Tighten the bolts to 102 Nzm (75 ft-lbs) torque.
GENERATOR SPLASH SHIELD
REMOVAL
(1) Remove the shield retaining nut and washer
(Fig. 2) from the engine oil pan stud (2.5L engines
only).
Fig. 1 Front Bumper Rail, Crossmember Cover &
Tow Hooks
13 - 14 FRAME AND BUMPERSJ

line. You may encounter fuels containing 3 percent
or more methanol along with other alcohols called co-
solvents.
Problems that are the result of using methanol/gas-
oline blends are not the responsibility of Chrysler
Corporation. They may not be covered by the vehicle
warranty.
MTBE/ETBE
Gasoline and MTBE (Methyl Tertiary Butyl Ether)
blends are a mixture of unleaded gasoline and up to
15 percent MTBE. Gasoline and ETBE (Ethyl Ter-
tiary Butyl Ether) are blends of gasoline and up to
17 percent ETBE. Gasoline blended with MTBE or
ETBE may be used in your vehicle.CLEAN AIR GASOLINE
Many gasolines are now being blended that con-
tribute to cleaner air, especially in those areas of the
country where air pollution levels are high. These
new blends provide a cleaner burning fuel and some
are referred to asReformulated Gasoline.
In areas of the country where carbon monoxide lev-
els are high, gasolines are being treated with oxy-
genated materials such as MTBE, ETBE and
ethanol.
Chrysler Corporation supports these efforts toward
cleaner air and recommends that you use these gas-
olines as they become available.
FUEL DELIVERY SYSTEM
INDEX
page page
Fuel Filter............................... 8
Fuel Pressure Leak Down Test............... 7
Fuel Pressure Release Procedure............. 5
Fuel Pump Capacity Test................... 7
Fuel Pump Electrical Control................. 5Fuel Pump Module........................ 2
Fuel System Pressure Test.................. 5
Fuel Tubes/Lines/Hoses and Clamps........... 9
Quick-Connect Fittings..................... 9
FUEL PUMP MODULE
The fuel pump module is installed in the top of the
fuel tank. The fuel pump module contains the follow-
ing components:
²Electric fuel pump
²Fuel pump reservoir
²In-tank fuel filter
²Fuel gauge sending unit
²Fuel supply and return tube connections
The fuel pump used on all vehicles is a gear/rotor
type pump. It is driven by a permanent magnet 12
volt electric motor that is immersed in the fuel tank.
The electrical pump is integral with the fuel sender
unit. The pump/sender assembly is installed inside
the fuel tank.
The fuel pump has a check valve at the outlet end
that consists of a ball held against a seat by force ap-
plied from a spring. When the pump is operating,
fuel pressure overcomes spring pressure and forces
the ball off its seat, allowing fuel to flow. When the
pump is not operating, spring pressure forces the ball
back against the seat preventing fuel backflow
through the pump.
Fuel system pressure is maintained at approxi-
mately 214 kPa (31 psi). This is when the pump is
operating and vacuum is supplied to the fuel pres-
sure regulator. If vacuum is not supplied to the pres-
sure regulator, fuel pressure will be approximately
55-69 kPa (8-10 psi) higher. This may be due to a
broken or clogged vacuum line. When the fuel pumpis not operating, system fuel pressure of 131-269 kPa
(19-39 psi) is maintained. This is done by the fuel
pump outlet check valve and the vacuum assisted
fuel pressure regulator.
REMOVALÐXJ MODELS
The fuel pump/gauge sender unit assembly can be
removed from the fuel tank without removing the
tank from the vehicle.
WARNING: THE FUEL SYSTEM IS UNDER A CON-
STANT PRESSURE (EVEN WITH THE ENGINE OFF).
BEFORE SERVICING THE FUEL PUMP MODULE,
THE FUEL SYSTEM PRESSURE MUST BE RE-
LEASED. REFER TO THE FUEL PRESSURE RE-
LEASE PROCEDURE IN THIS GROUP.
WARNING: EXTINGUISH ALL TOBACCO SMOKING
PRODUCTS BEFORE SERVICING THE FUEL SYS-
TEM. KEEP OPEN FLAME AWAY FROM FUEL SYS-
TEM COMPONENTS.
(1) Remove fuel filler cap. Perform the Fuel Pres-
sure Release Procedure as outlined in this group.
(2) Disconnect negative battery cable.
(3) Using an approved portable gasoline siphon/
storage tank, drain fuel tank until fuel level is below
one quarter (1/4) full.
(4) Raise and support vehicle.
14 - 2 FUEL SYSTEMJ

WARNING: WRAP SHOP TOWELS AROUND FUEL
HOSES TO ABSORB ANY FUEL SPILLAGE DURING
FUEL TANK REMOVAL.
(5) Disconnect fuel vent supply and return tubes
from fittings on fuel pump module.
(6) Disconnect fuel pump module electrical harness
connector from main harness.
(7) Using a brass punch and hammer, remove fuel
pump module lock ring by carefully tapping it coun-
terclockwise (Fig. 1).
(8) Remove fuel pump module and O-ring seal.
Discard old O-ring and fuel pump module inlet filter.
DISASSEMBLYÐXJ MODELS
(1) Remove and discard fuel pump inlet filter.
The wire terminals to the fuel pump motor are dif-
ferent in size and cannot be connected to the wrong
terminal.
(2) Disconnect fuel pump terminal wires.
(3) Remove fuel pump outlet hose and clamp. Re-
place the hose if it shows any signs of fatigue or fail-
ure.
(4) Remove fuel pump top mounting bracket nut.
Remove fuel pump (Fig. 2).
ASSEMBLYÐXJ MODELS
Whenever the fuel pump is replaced, the fuel pump
inlet filter (sock) must also be replaced.
(1) Place fuel pump top mounting bracket over top
of pump.
(2) Position fuel pump into lower bracket. Slide
stud of top bracket through hole in fuel pump side
bracket. Tighten fuel pump top mounting nut.
(3) Install new fuel pump outlet hose. Secure with
new clamps.
(4) Connect wire terminals to motor.
(5) Install new fuel pump inlet filter.
INSTALLATIONÐXJ MODELS
Whenever the fuel pump is replaced, the fuel
pump inlet filter must also be replaced.
(1) Install new fuel pump inlet filter onto fuel
pump.
(2) Install fuel pump module assembly and new O-
ring seal. The rubber stopper on the end of the fuel
return tube of the assembly must be inserted into the
cup in the fuel tank reservoir (Fig. 3).
Fig. 1 Removing Lock RingÐXJ ModelsÐTypical
Fig. 2 Fuel Pump ModuleÐXJ
ModelsÐDisassemble/Assemble
Fig. 3 Fuel Pump ModuleÐXJ ModelsÐInstallation
JFUEL SYSTEM 14 - 3