ABS JEEP CHEROKEE 1994 Service Repair Manual

ENGINES
CONTENTS
page page
2.5L ENGINE SERVICE PROCEDURES....... 9
4.0L ENGINE SERVICE PROCEDURES...... 50ENGINE DIAGNOSIS...................... 5
STANDARD SERVICE PROCEDURES......... 1
STANDARD SERVICE PROCEDURES
INDEX
page page
Engine Performance....................... 2
Form-In-Place Gaskets..................... 1
Honing Cylinder Bores..................... 2
Hydrostatic Lock.......................... 4Measuring with Plastigage................... 3
Repair Damaged or Worn Threads............ 4
Service Engine Assembly (Short Block)......... 4
FORM-IN-PLACE GASKETS
There are several places where form-in-place gas-
kets are used on the engine.DO NOT use form-in-
place gasket material unless specified.Care must
be taken when applying form-in-place gaskets. Bead
size, continuity and location are of great importance.
Too thin a bead can result in leakage while too much
can result in spill-over. A continuous bead of the
proper width is essential to obtain a leak-free joint.
Two types of form-in-place gasket materials are
used in the engine area (Mopar Silicone Rubber Ad-
hesive Sealant and Mopar Gasket Maker). Each have
different properties and cannot be used interchange-
ably.
MOPAR SILICONE RUBBER ADHESIVE
SEALANT
Mopar Silicone Rubber Adhesive Sealant, normally
black in color, is available in 3 ounce tubes. Moisture
in the air causes the sealant material to cure. This
material is normally used on flexible metal flanges.
It has a shelf life of a year and will not properly cure
if over aged. Always inspect the package for the ex-
piration date before use.
MOPAR GASKET MAKER
Mopar Gasket Maker, normally red in color, is
available in 6 cc tubes. This anaerobic type gasket
material cures in the absence of air when squeezed
between smooth machined metallic surfaces. It will
not cure if left in the uncovered tube. DO NOT use
on flexible metal flanges.
SURFACE PREPARATION
Parts assembled with form-in-place gaskets may be
disassembled without unusual effort. In some in-
stances, it may be necessary to lightly tap the part
with a mallet or other suitable tool to break the seal
between the mating surfaces. A flat gasket scraper
may also be lightly tapped into the joint but care
must be taken not to damage the mating surfaces.
Scrape or wire brush all gasket surfaces to remove
all loose material. Inspect stamped parts to ensure
gasket rails are flat. Flatten rails with a hammer on
a flat plate, if required. Gasket surfaces must be free
of oil and dirt. Make sure the old gasket material is
removed from blind attaching holes.
GASKET APPLICATION
Assembling parts using a form-in-place gasket re-
quires care.
Mopar Silicone Rubber Adhesive Sealant should be
applied in a continuous bead approximately 3 mm
(0.12 inch) in diameter. All mounting holes must be
circled. For corner sealing,a3or6mm(1/8 or 1/4
inch) drop is placed in the center of the gasket con-
tact area. Uncured sealant may be removed with a
shop towel. Components should be torqued in place
while the sealant is still wet to the touch (within 10
minutes). The use of a locating dowel is recom-
mended during assembly to prevent smearing the
material off location.
Mopar Gasket Maker should be applied sparingly
to one gasket surface. The sealant diameter should
be 1.00 mm (0.04 inch) or less. Be certain the mate-
rial surrounds each mounting hole. Excess material
JENGINES 9 - 1

(2) Install the upper inner retainer and bushing on
the top of the damper.
(3) Position the upper damper bracket over the
damper and install the stud nut and bolts.
(4) Tighten the stud nut to 23 Nzm (17 ft. lbs.)
torque. Tighten the bracket bolts to 61 Nzm (45 ft.
lbs.) torque.
(5) Install the bushing, upper outer retainer and
damper nut.
(6) Install the bushing, lower outer retainer and
damper nut.
(7) Tighten the upper and lower damper nuts.
(8) Connect negative cable to battery.
ENGINE ASSEMBLYÐXJ VEHICLES
REMOVAL
(1) Disconnect the battery cables. Remove the bat-
tery.
(2) Mark the hinge locations on the hood panel for
alignment reference during installation. Remove the
engine compartment lamp. Remove the hood.
WARNING: THE COOLANT IN A RECENTLY OPER-
ATED ENGINE IS HOT AND PRESSURIZED. USE
CARE TO PREVENT SCALDING BY HOT COOLANT.
CAREFULLY RELEASE THE PRESSURE BEFORE
REMOVING THE RADIATOR DRAIN COCK AND
CAP.(3) Remove the radiator drain cock and radiator
cap to drain the coolant. DO NOT waste usable cool-
ant. If the solution is clean, drain the coolant into a
clean container for reuse.
(4) Remove the lower radiator hose.
(5) Remove the upper radiator hose and coolant re-
covery hose (Fig. 15).
(6) Remove the fan shroud (Fig. 15).
(7) Disconnect the transmission fluid cooler tubing
(automatic transmission).
(8) Remove the radiator/condenser (if equipped
with air conditioning).
(9) Remove fan assembly and install a 5/16 x 1/2-
inch SAE capscrew through fan pulley into water
pump flange. This will maintain the pulley and wa-
ter pump in alignment when crankshaft is rotated.
(10) Disconnect the heater hoses (Figs. 16 and 17).
(11) Disconnect the throttle linkages (Fig. 16),
speed control cable (if equipped) and throttle valve
rod.
(12) Disconnect the oxygen sensor wire connector.
(13) Disconnect the wires from the starter motor
solenoid.
(14) Disconnect all fuel injection harness connec-
tions.
(15) Disconnect the quick-connect fuel lines at the
fuel rail and return line by squeezing the two retain-
ing tabs against the fuel tube (Fig. 16). Pull the fuel
tube and retainer from the quick-connect fitting (re-
fer to Group 14, Fuel System for the proper proce-
dure).
(16) Remove the fuel line bracket from the intake
manifold.
(17) Remove the air cleaner assembly (Fig. 18).
(18) If equipped with air conditioning, remove the
service valves and cap the compressor ports.
(19) Remove the power brake vacuum check valve
from the booster, if equipped.
(20) If equipped with power steering (Fig. 18):
Fig. 14 Engine Damper
Fig. 15 Upper Radiator Hose, Coolant Recovery
Hose & Fan Shroud
9 - 14 2.5L ENGINEJ

(7) Disconnect the wires at the starter motor sole-
noid and injection wire harness connector.
(8) Disconnect the quick-connect fuel lines at the
fuel rail and return line by squeezing the two retain-
ing tabs against the fuel tube (Fig. 20). Pull the fuel
tube and retainer from the quick-connect fitting (re-
fer to Group 14, Fuel System for the proper proce-
dure).
(9) Remove the fuel line bracket from the intake
manifold.
(10) Disconnect the engine ground strap.
(11) Remove the air cleaner assembly.
(12) Disconnect the vacuum purge hose at the fuel
vapor canister tee.
(13) Disconnect the idle speed actuator wire con-
nector.
(14) Disconnect the throttle cable and remove it
from the bracket.
(15) Disconnect the throttle rod at the bellcrank.
(16) Disconnect the speed control cable, if
equipped.
(17) Disconnect the oxygen sensor wire connector.
(18) Disconnect the upper and lower radiator hoses
at the radiator.
(19) Disconnect the coolant hoses from the rear of
the intake manifold and thermostat housing.
(20) Disconnect the heater hoses.
(21) Remove the fan shroud screws.
(22) Remove the radiator attaching bolts.
(23) Remove the radiator and fan shroud.
(24) Remove the fan and spacer or Tempatrol fan
assembly.
(25) Install a 5/16 X 1/2-inch SAE capscrew
through fan pulley into water pump flange. This will
maintain the pulley and water pump in alignment
when crankshaft is rotated.
(26) Remove the power brake vacuum check valve
from the booster, if equipped.
(27) If equipped with power steering:(a) Disconnect the hoses from the fittings at the
steering gear.
(b) Drain the pump reservoir.
(c) Cap the fittings on the hoses and steering
gear to prevent foreign objects from entering the
system.
(28) Lift the vehicle and support it with support
stands.
(29) Remove the oil filter.
(30) Remove the starter motor.
(31) Remove the flywheel housing access cover.
(32) Remove the engine support cushion-to-bracket
through bolts.
(33) Disconnect the exhaust pipe from the mani-
fold.
(34) Remove the upper flywheel housing bolts and
loosen the bottom bolts.
(35) Remove the engine shock damper bracket
from the sill.
(36) Lower the vehicle.
(37) Attach a lifting device to the engine.
(38) Raise the engine off the front supports.
(39) Place a support stand under the flywheel
housing.
(40) Remove the remaining flywheel housing bolts.
(41) Lift the engine out of the engine compartment
and install on an engine stand.
(42) Install the oil filter to keep foreign material
out of the engine.
INSTALLATION
(1) Remove the oil filter.
(2) Lift the engine off the stand and lower it into
the engine compartment. For easier installation, it
may be useful to remove the engine support cushions
from the engine support brackets as an aide for
alignment of the engine-to-transmission.
(3) Insert the transmission shaft into the clutch
spline.
(4) Align the flywheel housing with the engine.
(5) Install and finger tighten the flywheel housing
lower bolts.
(6) Install the engine support cushions (if re-
moved).
(7) Remove the support stand from beneath the fly-
wheel housing.
(8) Lower the engine and engine support cushions
onto the engine compartment brackets. Ensure that
the bolt holes are aligned. Install the bolts and
tighten.
(9) Remove the engine lifting device.
(10) Raise the vehicle.
(11) Attach the engine shock damper bracket to
the sill.
(12) Attach the exhaust pipe to the manifold. In-
stall and tighten the nuts to 31 Nzm (23 ft. lbs.)
torque.
(13) Install the flywheel housing access cover.
Fig. 20 Fuel Line Quick-Connect Couplings
J2.5L ENGINE 9 - 17

(75 psi). In the relief position, the valve permits oil
to bypass through a passage in the pump body to the
inlet side of the pump.
Oil pump removal or replacement will not affect
the distributor timing because the distributor drive
gear remains in mesh with the camshaft gear.
REMOVAL
(1) Drain the engine oil.
(2) Remove the oil pan.
(3) Remove the pump-to-cylinder block attaching
bolts. Remove the pump assembly with gasket (Fig.
4).
CAUTION: If the oil pump is not to be serviced, DO
NOT disturb position of oil inlet tube and strainer
assembly in pump body. If the tube is moved within
the pump body, a replacement tube and strainer as-
sembly must be installed to assure an airtight seal.
INSTALLATION
(1) Install the oil pump on the cylinder block using
a replacement gasket. Tighten the short bolt to 14
Nzm (10 ft. lbs.) torque and the long bolt to 23 Nzm
(17 ft. lbs.) torque.
(2) Install the oil pan.
(3) Fill the oil pan with oil to the specified level.
OIL PUMP PRESSURE
The MINIMUM oil pump pressure is 89.6 kPa (13
psi) at 600 rpm. The MAXIMUM oil pump pressure
is 255-517 kPa (37-75 psi) at 1600 rpm or more.
PISTONS AND CONNECTING RODS
REMOVAL
(1) Remove the engine cylinder head cover.
(2) Remove the rocker arms, bridges and pivots.
(3) Remove the push rods.
(4) Remove the engine cylinder head.
(5) Position the pistons one at a time near the bot-
tom of the stroke. Use a ridge reamer to remove the
ridge from the top end of the cylinder walls. Use a
protective cloth to collect the cuttings.
(6) Raise the vehicle.
(7) Drain the engine oil.
(8) Remove the oil pan and gasket.
(9) Remove the connecting rod bearing caps and
inserts. Mark the caps and rods with the cylinder
bore location. The connecting rods and caps are
stamped with a two letter combination (Fig. 1).
(10) Lower the vehicle until it is about 2 feet from
the floor.
CAUTION: Ensure that the connecting rod bolts DO
NOT scratch the crankshaft journals or cylinder
walls. Short pieces of rubber hose, slipped over the
rod bolts will provide protection during removal.
(11) Have an assistant push the piston/connecting
rod assemblies up and through the top of the cylinder
bores (Fig. 2).
INSPECTIONÐCONNECTING ROD
CONNECTING ROD BEARINGS
Inspect the connecting rod bearings for scoring and
bent alignment tabs (Figs. 3 and 4). Check the bear-
ings for normal wear patterns, scoring, grooving, fa-
tigue and pitting (Fig. 5). Replace any bearing that
shows abnormal wear.
Fig. 4 Oil Pump Assembly
Fig. 1 Stamped Connecting Rods and Caps
9 - 34 2.5L ENGINEJ

(6) Remove the lower insert from the bearing cap.
(7) Remove the upper insert by LOOSENING (DO
NOT REMOVE) all of the other bearing caps. Now
insert a small cotter pin tool in the crankshaft jour-
nal oil hole. Bend the cotter pin as illustrated to fab-
ricate the tool (Fig. 2). With the cotter pin tool in
place, rotate the crankshaft so that the upper bear-
ing insert will rotate in the direction of its locking
tab. Because there is no hole in the No.3 main jour-
nal, use a tongue depressor or similar soft-faced tool
to remove the bearing insert (Fig. 2). After moving
the insert approximately 25 mm (1 inch), it can be
removed by applying pressure under the tab.
(8) Using the same procedure described above, re-
move the remaining bearing inserts one at a time for
inspection.
INSPECTION
Wipe the inserts clean and inspect for abnormal
wear patterns and for metal or other foreign material
imbedded in the lining. Normal main bearing insert
wear patterns are illustrated (Fig. 3).
If any of the crankshaft journals are scored,
remove the engine for crankshaft repair.
Inspect the back of the inserts for fractures, scrap-
ings or irregular wear patterns.
Inspect the upper insert locking tabs for damage.
Replace all damaged or worn bearing inserts.
FITTING (CRANKSHAFT INSTALLED)
The main bearing caps, numbered (front to rear)
from 1 through 5 have an arrow to indicate the for-
ward position. The upper main bearing inserts are
grooved to provide oil channels while the lower in-
serts are smooth.Each bearing insert pair is selectively fitted to its
respective journal to obtain the specified operating
clearance. In production, the select fit is obtained by
using various-sized color-coded bearing insert pairs
as listed in the Main Bearing Fitting Chart. The
bearing color code appears on the edge of the insert.
The size is not stamped on bearing inserts used
for engine production.
The main bearing journal size (diameter) is identi-
fied by a color-coded paint mark on the adjacent
cheek. The rear main journal, is identified by a color-
coded paint mark on the crankshaft rear flange.
When required, upper and lower bearing inserts of
different sizes may be used as a pair. A standard size
insert is sometimes used in combination with a 0.025
mm (0.001 inch) undersize insert to reduce the clear-
ance by 0.013 mm (0.0005 inch).Never use a pair
of bearing inserts with greater than a 0.025 mm
(0.001 inch) difference in size (Fig. 4).
When replacing inserts, the odd size inserts
must be either all on the top (in cylinder block)
or all on the bottom (in main bearing cap).
Once the bearings have been properly fitted, pro-
ceed to Crankshaft Main BearingÐInstallation.
Fig. 2 Removing Upper Inserts
Fig. 3 Main Bearing Wear Patterns
Fig. 4 Bearing Insert Pairs
J2.5L ENGINE 9 - 41

(6) Remove upper radiator support retaining bolts
and remove radiator support.
(7) Remove the fan shroud (Fig. 13) and electric
cooling fan.
(8) Disconnect the transmission fluid cooler tubing
(automatic transmission).
(9) Disconnect radiator fan switch wire connector.
(10)Vehicles with Air Conditioning:
(a) Discharge the A/C condenser.
(b) Remove the service valves and cap the com-
pressor ports.
(11) Remove the radiator or radiator/condenser (if
equipped with A/C).
(12) Remove the fan assembly from the idler pul-
ley.
(13) Disconnect the heater hoses at the engine
thermostat housing and water pump (Figs. 13 and
14).
(14) Disconnect the throttle linkages (Fig. 15).
(15) Disconnect the speed control cable (if
equipped)Ð(Fig. 15).(16) Disconnect the line pressure cable (if equipped
with automatic transmission).
(17) Disconnect injection system wire harness con-
nector at the dash panel.
(18) Disconnect the distributor electrical connec-
tion and the oil pressure switch connector.
(19) Disconnect the quick-connect fuel lines at the
fuel rail and return line by squeezing the two retain-
ing tabs against the fuel tube (Fig. 15). Pull the fuel
tube and retainer from the quick-connect fitting (re-
fer to Group 14, Fuel System for the proper proce-
dure).
(20) Remove the fuel line bracket from the intake
manifold.
(21) Remove the air cleaner assembly (Fig. 16).
(22) Remove the power brake vacuum check valve
from the booster, if equipped.
(23) If equipped with power steering (Fig. 16):
(a) Disconnect the hoses from the fittings at the
steering gear.
(b) Drain the pump reservoir.
(c) Cap the fittings on the hoses and steering
gear to prevent foreign objects from entering the
system.
(24) Identify, tag and disconnect all necessary wire
connectors and vacuum hoses.
(25) Raise and support the vehicle.
(26) Disconnect the wires from the starter motor
solenoid.
(27) Remove the starter motor.
(28) Disconnect the exhaust pipe from the mani-
fold.
Fig. 13 Upper Radiator Hose, Coolant Recovery
Hose, Fan Shroud & Heater hoses
Fig. 14 Heater Hoses (RH Drive Vehicle)
Fig. 15 Accelerator Cable, Speed Control Cable,
Automatic Transmission Control Cable & Quick-
Connect Fuel Lines
J4.0L ENGINE 9 - 55

(28) Connect the heater hoses at the engine ther-
mostat housing and water pump.
(29) Install the fan assembly to the idler pulley.
(30) Install the radiator or radiator/condenser (if
equipped with A/C).
(31) Connect the service valves to the A/C com-
pressor ports, if equipped with A/C.
(32) Charge the air conditioner system.
(33) Connect radiator fan switch wire.
(34) Connect the radiator hoses and automatic
transmission fluid cooler pipes, if equipped.
(35) Install the fan shroud, electric cooling fan and
radiator/condenser (if equipped with A/C).
(36) Install upper radiator support.
(37) Connect the upper radiator hose and tighten
the clamp.
(38) Connect the lower radiator hose and tighten
the clamp.
(39) Fill the cooling system with reusable coolant
and/or new coolant.
(40) Align the hood to the scribe marks. Install the
hood.
(41) Connect the vacuum harness connector.
(a) Firmly push the connectors together ensuring
that the retaining tabs are engaged.
(b) Insert the vacuum connector assembly into
the retaining bracket on the intake manifold.
(42) Install the air cleaner assembly.
(43) Install the battery and connect the battery ca-
ble.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A DI-
RECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR FAN. DO
NOT WEAR LOOSE CLOTHING.
(44) Start the engine, inspect for leaks and correct
the fluid levels, as necessary.
ENGINE ASSEMBLYÐYJ VEHICLES
REMOVAL
(1) Place a protective cloth over the windshield
frame. Raise the hood and rest it on the windshield
frame (Fig. 17).
(2) Disconnect the battery cables. Remove the bat-
tery.
WARNING: THE COOLANT IN A RECENTLY OPER-
ATED ENGINE IS HOT AND PRESSURIZED. USE
CARE TO PREVENT SCALDING BY HOT COOLANT.
CAREFULLY RELEASE THE PRESSURE BEFORE
REMOVING THE RADIATOR DRAIN COCK AND
CAP.
(3) Remove the radiator drain cock and radiator
cap to drain the coolant. DO NOT waste reusablecoolant. If the solution is clean, drain the coolant
into a clean container for reuse.
(4) Disconnect the wire connectors from the gener-
ator.
(5) Disconnect the ignition coil and distributor
wire connectors.
(6) Disconnect the oil pressure sender wire connec-
tor.
(7) Disconnect the wires at the starter motor sole-
noid and injection wire harness connector.
(8) Disconnect the quick-connect fuel lines at the
fuel rail and return line by squeezing the retaining
tabs against the fuel tube (Fig. 18). Pull the fuel
tube and retainer from the quick-connect fitting (re-
fer to Group 14, Fuel System for the proper proce-
dure).
(9) Remove the fuel line bracket from the intake
manifold.
(10) Disconnect the engine ground strap.
(11) Remove the air cleaner (Fig. 18).
(12) Disconnect the vacuum purge hose at the fuel
vapor canister tee.
(13) Disconnect the idle speed actuator wire con-
nector.
(14) Disconnect the throttle cable and remove it
from the bracket (Fig. 18).
(15) Disconnect the throttle rod at the bellcrank.
(16) Disconnect the speed control cable, if equipped
(Fig. 18).
(17) Disconnect the oxygen sensor wire connector.
(18) Remove the upper radiator hose and coolant
recovery hose (Fig. 19).
(19) Disconnect lower radiator hoses at the radia-
tor.
Fig. 17 Hood on Windshield Frame
J4.0L ENGINE 9 - 57

INSPECTIONÐCONNECTING ROD
CONNECTING ROD BEARINGS
Inspect the connecting rod bearings for scoring and
bent alignment tabs (Figs. 3 and 4). Check the bear-
ings for normal wear patterns, scoring, grooving, fa-
tigue and pitting (Fig. 5). Replace any bearing that
shows abnormal wear.
Inspect the connecting rod journals for signs of
scoring, nicks and burrs.CONNECTING RODS
Misaligned or bent connecting rods can cause ab-
normal wear on pistons, piston rings, cylinder walls,
connecting rod bearings and crankshaft connecting
rod journals. If wear patterns or damage to any of
these components indicate the probability of a mis-
aligned connecting rod, inspect it for correct rod
alignment. Replace misaligned, bent or twisted con-
necting rods.
BEARING-TO-JOURNAL CLEARANCE
(1) Wipe the oil from the connecting rod journal.
(2) Use short rubber hose sections over rod bolts
during installation.
(3) Lubricate the upper bearing insert and install
in connecting rod.
(4) Use piston ring compressor to install the rod
and piston assemblies. The oil squirt holes in the
rods must face the camshaft. The arrow on the piston
crown should point to the front of the engine (Fig. 6).
Verify that the oil squirt holes in the rods face the
camshaft and that the arrows on the pistons face the
front of the engine.
(5) Install the lower bearing insert in the bearing
cap. The lower insert must be dry. Place strip of Plas-
tigage across full width of the lower insert at the cen-
ter of bearing cap. Plastigage must not crumble in
use. If brittle, obtain fresh stock.
(6) Install bearing cap and connecting rod on the
journal and tighten nuts to 45 Nzm (33 ft. lbs.)
torque. DO NOT rotate crankshaft. Plastigage will
smear, resulting in inaccurate indication.
(7) Remove the bearing cap and determine amount
of bearing-to-journal clearance by measuring the
width of compressed Plastigage (Fig. 7). Refer to En-
gine Specifications for the proper clearance.Plasti-
gage should indicate the same clearance across
the entire width of the insert. If the clearance
varies, it may be caused by either a tapered
Fig. 3 Connecting Rod Bearing Inspection
Fig. 4 Locking Tab Inspection
Fig. 5 Scoring Caused by Insufficient Lubrication or
by Damaged Crankshaft Pin Journal
Fig. 6 Rod and Piston Assembly Installation
J4.0L ENGINE 9 - 75

the insert approximately 25 mm (1 inch), it can be
removed by applying pressure under the tab.
(8) Using the same procedure described above, re-
move the remaining bearing inserts one at a time for
inspection.
INSPECTION
Wipe the inserts clean and inspect for abnormal
wear patterns and for metal or other foreign material
imbedded in the lining. Normal main bearing insert
wear patterns are illustrated (Fig. 3).
If any of the crankshaft journals are scored,
remove the engine for crankshaft repair.
Inspect the back of the inserts for fractures, scrap-
ings or irregular wear patterns.
Inspect the upper insert locking tabs for damage.
Replace all damaged or worn bearing inserts.
FITTING (CRANKSHAFT INSTALLED)
The main bearing caps, numbered (front to rear)
from 1 through 7 have an arrow to indicate the for-
ward position. The upper main bearing inserts are
grooved to provide oil channels while the lower in-
serts are smooth.
Each bearing insert pair is selectively fitted to its
respective journal to obtain the specified operating
clearance. In production, the select fit is obtained by
using various-sized color-coded bearing insert pairs
as listed in the Main Bearing Fitting Chart. The
bearing color code appears on the edge of the insert.
The size is not stamped on bearing inserts used
for engine production.
The main bearing journal size (diameter) is identi-
fied by a color-coded paint mark on the adjacent
cheek. The rear main journal, is identified by a color-
coded paint mark on the crankshaft rear flange.
When required, upper and lower bearing inserts of
different sizes may be used as a pair. A standard size
insert is sometimes used in combination with a 0.025
mm (0.001 inch) undersize insert to reduce the clear-
ance by 0.013 mm (0.0005 inch).Never use a pair
of bearing inserts with greater than a 0.025 mm
(0.001 inch) difference in size (Fig. 4).
When replacing inserts, the odd size inserts
must be either all on the top (in cylinder block)
or all on the bottom (in main bearing cap).
Once the bearings have been properly fitted, pro-
ceed to Crankshaft Main BearingÐInstallation.
BEARING-TO-JOURNAL CLEARANCE (CRANKSHAFT
INSTALLED)
When using Plastigage, check only one bearing
clearance at a time.
Install the grooved main bearings into the cylinder
block and the non-grooved bearings into the bearing
caps.
Install the crankshaft into the upper bearings dry.
Place a strip of Plastigage across full width of the
crankshaft journal to be checked.
Install the bearing cap and tighten the bolts to 108
Nzm (80 ft. lbs.) torque.
Fig. 2 Removing Upper Inserts
Fig. 3 Main Bearing Wear Patterns
Fig. 4 Bearing Insert Pairs
J4.0L ENGINE 9 - 81

INTAKE MANIFOLDÐ2.5L ENGINE
REMOVAL
(1) Disconnect the battery negative cable.
(2) Remove the air inlet hose from the throttle
body and air cleaner.
(3) Loosen the accessory drive belt tension and re-
move the belt from the power steering pump.
(4) Remove the power steering pump and brackets
from the water pump and intake manifold. Support
power steering pump and bracket with mechanics
wire attached to the radiator upper crossmember.
(5) Remove the fuel tank filler cap to relieve the
fuel tank pressure.
(6) Install the fuel tank filler cap.
(7) Disconnect fuel supply and return tube from
the fuel rail (refer to Group 14, Fuel System - Quick
Connect Fittings).
(8) Disconnect the accelerator cable from the throt-
tle body and the holddown bracket.
CAUTION: When disconnecting the cruise control
connector at the throttle body, DO NOT pry the con-
nector off with pliers or screwdriver. Use finger
pressure only. Prying the connector off could break
it.
(9) Disconnect the electrical connectors. Pull the
harnesses away from the manifold.
²The throttle position sensor.
²The idle speed control motor.
²The coolant temperature sensor at the thermostat.
²The manifold air temperature sensor at the intake
manifold.
²The fuel injectors.
²The oxygen sensor.
(10) Disconnect the crankcase ventilation (CCV)
vacuum hose and manifold absolute pressure (MAP)
sensor vacuum hose connector at the intake mani-
fold.
(11) Disconnect vacuum hose from vacuum port on
the intake manifold.
(12) Disconnect CCV hose at the cylinder head
cover (Fig. 12).
(13) Remove the molded vacuum harness.
(14) Disconnect the vacuum brake booster hose at
the intake manifold.
(15) Remove bolts 2 through 5 securing the intake
manifold to the cylinder head (Fig. 11). Slightly
loosen bolt No.1 and nuts 6 and 7.
(16) Remove the intake manifold and gaskets.
Drain the coolant from the manifold.
CLEANING
Clean the intake manifold and cylinder head mat-
ing surfaces.DO NOT allow foreign material to
enter either the intake manifold or the ports in
the cylinder head.
INSTALLATION
(1) Install the new intake manifold gasket over the
locating dowels.
(2) Position the manifold in place and finger
tighten the mounting bolts.
(3) Tighten the fasteners in sequence and to the
specified torque (Fig. 11).
²Fastener No.1ÐTighten to 41 Nzm (30 ft. lbs.)
torque.
²Fasteners Nos.2 through 7ÐTighten to 31 Nzm (23
ft. lbs.) torque.
(4) Connect the fuel return and supply tube to the
connector next to the fuel rail. Push them into the
fitting until a click is heard. Verify that the connec-
tions are complete.
²First, ensure only the retainer tabs protrude from
the connectors.
²Second, pull out on the fuel tubes to ensure they
are locked in place.
(5) Connect the molded vacuum hoses to the vac-
uum port on the intake manifold and the cylinder
head cover.
(6) Connect the electrical connectors.
²The throttle position sensor.
²The automatic idle speed control motor.
²The coolant temperature sensor at the thermostat
housing.
²The fuel injectors.
²The air manifold temperature sensor.
²The oxygen sensor.
(7) Connect the CCV vacuum hose and MAP sen-
sor vacuum hose connectors to the throttle body.
(8) Install the power steering pump and bracket
assembly to the water pump and intake manifold.
(9) Connect the accelerator cable and cruise control
cable to the holddown bracket and the throttle arm.
Fig. 12 Crankcase Ventilation (CCV) Hose
(2.5L Engine)
11 - 8 EXHAUST SYSTEM AND INTAKE MANIFOLDJ