1994 JEEP CHEROKEE cooling

(8) Remove the tools. Apply a light film of engine
oil on the vibration damper hub contact surface of
the seal.
(9) Apply Mopar Silicone Rubber Adhesive Sealant
to the keyway in the crankshaft and insert the key.
With the key inserted in the keyway in the crank-
shaft, install the vibration damper, washer and bolt.
Lubricate and tighten the bolt to 108 Nzm (80 ft. lbs.)
torque.
(10) Install the serpentine belt and tighten to the
specified tension (refer to Group 7, Cooling Systems
for the proper specifications and procedures).
(11) Install the radiator shroud.
(12) Connect negative cable to battery.
TIMING CASE COVER
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove the vibration damper (Fig. 4).
(3) Remove the fan and hub assembly and remove
the fan shroud.
(4) Remove the accessory drive brackets that are
attached to the timing case cover.
(5) Remove the A/C compressor (if equipped) and
generator bracket assembly from the engine cylinder
head and move to one side.
(6) Remove the oil pan-to-timing case cover bolts
and timing case cover-to-cylinder block bolts.
(7) Remove the timing case cover and gasket from
the engine.
(8) Pry the crankshaft oil seal from the front of the
timing case cover (Fig. 4).
CLEANING
Clean the timing case cover, oil pan and cylinder
block gasket surfaces.
INSTALLATION
(1) Install a new crankshaft oil seal in the timing
case cover. The open end of the seal should be toward
the inside of the cover. Support the cover at the seal
area while installing the seal. Force it into position
with Seal Installation Tool 6139.
(2) Position the gasket on the cylinder block.
(3) Position the timing case cover on the oil pan
gasket and the cylinder block.
(4) Insert Timing Case Cover Alignment and Seal
Installation Tool 6139 in the crankshaft opening in
the cover (Fig. 5).
(5) Install the timing case cover-to-cylinder block
and the oil pan-to-timing case cover bolts.
(6) Tighten the 1/4 inch cover-to-block bolts to 7
Nzm (60 in. lbs.) torque. Tighten the 5/16 inch front
cover-to-block bolts to 22 Nzm (192 in. lbs.) torque.
Tighten the oil pan-to-cover 1/4 inch bolts to 14 Nzm
(120 in. lbs.) torque. Tighten the oil pan-to-cover 5/16
inch bolts to 18 Nzm (156 in. lbs.) torque.
(7) Remove the cover alignment tool.
Fig. 3 Timing Case Cover Oil Seal InstallationFig. 4 Timing Case Cover Components
Fig. 5 Timing Case Cover Alignment and Seal
Installation Tool 6139
J2.5L ENGINE 9 - 27

(7) Install the oil slinger.
(8) Replace the oil seal in the timing case cover.
(9) Install the timing case cover and gasket.
(10) With the key inserted in the keyway in the
crankshaft, install the vibration damper, washer and
bolt. Lubricate and tighten the bolt to 108 Nzm (80
ft. lbs.) torque.
(11) Install the fan and shroud.
(12) Connect negative cable to battery.
CAMSHAFT
REMOVAL
WARNING: THE COOLANT IN A RECENTLY OPER-
ATED ENGINE IS HOT AND PRESSURIZED. RE-
LEASE THE PRESSURE BEFORE REMOVING THE
DRAIN COCK, CAP AND DRAIN PLUGS.
(1) Disconnect negative cable from battery.
(2) Drain the cooling system. DO NOT waste reus-
able coolant. If the solution is clean, drain it into a
clean container for reuse.
(3) Remove the radiator or radiator/condenser, if
equipped with A/C (refer to Group 7, Cooling System
for the proper procedure).
(4) Scribe a mark on the distributor housing in
line with the lip of the rotor.
(5) Scribe a mark on the distributor housing near
the clamp and continue the scribe mark on the cyl-
inder block in line with the distributor mark.
(6) For ease of installation, note the position of the
rotor and distributor housing in relation to adjacent
engine components.
(7) Remove the distributor and ignition wires.(8) Remove the engine cylinder head cover.
(9) Remove the rocker arms, bridges and pivots.
(10) Remove the push rods.
(11) Remove the hydraulic valve tappets from the
engine cylinder head.
(12) Remove the vibration damper.
(13) Remove the timing case cover.
(14) Remove the timing chain and sprockets.
(15) Remove the camshaft (Fig. 10).
INSPECTION
Inspect the cam lobes for wear.
Inspect the bearing journals for uneven wear pat-
tern or finish.
Inspect the bearings for wear.
Inspect the distributor drive gear for wear.
If the camshaft appears to have been rubbing
against the timing case cover, examine the oil pres-
sure relief holes in the rear cam journal. The oil
pressure relief holes must be free of debris.
INSTALLATION
(1) Lubricate the camshaft with Mopar Engine Oil
Supplement, or equivalent.
(2) Carefully install the camshaft to prevent dam-
age to the camshaft bearings (Fig. 10).
(3) Install the timing chain, crankshaft sprocket
and camshaft sprocket with the timing marks
aligned.
(4) Install the camshaft sprocket retaining bolt and
washer. Tighten the bolt to 108 Nzm (80 ft. lbs.)
torque.
(5) Install the timing case cover with a replace-
ment oil seal (Fig. 11). Refer to Timing Case Cover
Installation.
(6) Install the vibration damper.
(7) Install the hydraulic valve tappets.
(8) Install the push rods.
(9) Install the rocker arms, bridges and pivots.
(10) Install the engine cylinder head cover.
(11) Install the distributor and ignition wires.
Fig. 9 Verify Sprocket/Chain Installation
Fig. 10 Camshaft
J2.5L ENGINE 9 - 29

(12) Properly position the distributor rotor as fol-
lows:
(a) Remove No.1 spark plug. Hold your finger
over the spark plug hole and rotate the crankshaft
until compression pressure is felt. Slowly continue
to rotate the crankshaft until the timing index on
the vibration damper aligns with the top dead cen-
ter (TDC) mark (0É on the timing degree scale).Al-
ways rotate the crankshaft clockwise (the
direction of normal rotation). DO NOT rotate
the crankshaft backward to align the timing
marks.
(b) Rotate the oil pump gear so that the gear slot
on the oil pump shaft is slightly past the 3 o'clock
position (Fig. 12). A flat blade screwdriver can be
used to rotate the gear.
(c) Turn the distributor shaft until the rotor tip
points in the direction of No.1 terminal in the dis-
tributor cap. Turn the rotor 1/8 turn counterclock-
wise past the position of No.1 terminal.
(d) With the distributor cap removed, start the
distributor into the cylinder block with the rotor lo-
cated at the 5 o'clock position (Fig. 13).
(e) Slide the distributor shaft down into the en-
gine. Position the distributor vacuum advance
mechanism housing in approximately the same lo-
cation as when removed. Align the scribe mark onthe distributor housing with the corresponding
scribe mark on the cylinder block. The rotor should
align with the position of No.1 terminal when the
distributor shaft is down in place. It may be neces-
sary to rotate the oil pump shaft with a long flat-
blade screwdriver to engage the oil pump drive
tang.
(f) Install the distributor holddown clamp and
bolt. DO NOT tighten the bolt.
(g) When the distributor is fully engaged in its
correct location, the rotor should be at the 6 o'clock
position (Fig. 14).
(h) If the distributor is not properly installed, or
if it is removed later, then the complete installa-
tion procedures must be repeated.
(13) Install the radiator or radiator/condenser, if
equipped with A/C.
(14) Fill the cooling system.
(15) Connect negative cable to battery.
Fig. 11 Timing Case Cover
Fig. 12 Oil Pump Gear Slot Alignment
Fig. 13 Distributor Rotor Pre-Positioning
Fig. 14 Correct Rotor Position
9 - 30 2.5L ENGINEJ

INSTALLATION
(1) Clean the camshaft pin hole.
(2) Compress the center of the replacement spring
pin with vise grips.
(3) Carefully drive the pin into the camshaft pin
hole until it is seated.
(4) Install the camshaft sprocket, crankshaft
sprocket and timing chain with the timing marks
aligned (Fig. 15).
(5) To verify correct installation of the timing
chain, turn the crankshaft to position the camshaft
sprocket timing mark as shown in Fig. 17. Count the
number of chain pins between the timing marks of
both sprockets. There must be 20 pins.
(6) Install the crankshaft oil slinger.
(7) Tighten the camshaft sprocket bolt to 108 Nzm
(80 ft. lbs.) torque.
(8) Check the valve timing.
(9) Coat both sides of the replacement timing case
cover gasket with gasket sealer. Applya3mm(1/8
inch) bead of Mopar Silicone Rubber Adhesive Seal-
ant, or equivalent to the joint formed at the timing
case cover and cylinder block.
(10) Position the timing case cover on the oil pan
gasket and the cylinder block.
(11) Place Timing Case Cover Alignment and Seal
Installation Tool 6139 in the crankshaft opening of
the cover (Fig. 18).
(12) Install the timing case cover-to-cylinder block
bolts. Install the oil pan-to-timing case cover bolts.
(13) Tighten the 1/4 inch cover-to-block bolts to 7
Nzm (60 in. lbs.) torque. Tighten the 5/16 inch front
cover-to-block bolts to 22 Nzm (192 in. lbs.) torque.
Tighten the oil pan-to-cover 1/4 inch bolts to 14 Nzm(120 in. lbs.) torque. Tighten the oil pan-to-cover 5/16
inch bolts to 18 Nzm (156 in. lbs.) torque.
(14) Remove the cover alignment tool and install a
replacement oil seal into the cover.
(15) Install the vibration damper on the crank-
shaft.
(16) Lubricate and tighten the damper bolt to 108
Nzm (80 ft. lbs.) torque.
(17) If equipped with air conditioning:
(a) Install the A/C compressor serpentine drive
belt idler pulley.
(b) Install the generator.
(c) Install the A/C condenser and receiver/drier
assembly.
(18) Install the serpentine drive belt on the pulleys
and tighten (refer to Group 7, Cooling System for the
specifications and procedures).
(19) Install the radiator. Connect the radiator
hoses and automatic transmission fluid cooler pipes,
if equipped. Fill the cooling system.
(20) Install the fan and shroud.
(21) Connect negative cable to battery.
OIL PAN
REMOVAL
(1) Disconnect negative cable from battery.
(2) Raise the vehicle.
(3) Remove the oil pan drain plug and drain the
engine oil.
(4) Disconnect the exhaust pipe at the engine ex-
haust manifold.
(5) Disconnect the exhaust hanger at the catalytic
converter and lower the pipe.
(6) Remove the engine starter motor.
(7) Remove the flywheel/torque converter housing
access cover.
(8) Position a jack stand directly under the engine
vibration damper.
Fig. 17 Verify Crankshaft/Camshaft Installation
Fig. 18 Timing Case Cover Alignment and Seal
Installation Tool 6139
9 - 32 2.5L ENGINEJ

²The feed holes for the crankshaft main bearings.
Once the block has been completely cleaned, apply
Loctite PST pipe sealant with Teflon 592 to the
threads of the front and rear oil galley plugs.
Tighten the plugs to 41 Nzm (30 ft. lbs.) torque.
INSPECTIONÐCYLINDER BORE
(1) Use a bore gauge to measure each cylinder bore
diameter (Fig. 12). If a bore gauge is not available,
use an inside micrometer.
(2) Measure the cylinder bore diameter crosswise
to the cylinder block near the top of the bore. Repeat
the measurement near the bottom of the bore.
(3) Determine taper by subtracting the smaller di-
ameter from the larger diameter.
(4) Rotate measuring device 120É and repeat steps
above. Finally, rotate the device another 120É and re-
peat measurements.
(5) Determine out-of-roundness by comparing the
difference between each 120É measurement.(6) If cylinder bore taper does not exceed 0.025 mm
(0.001 inch) and out-of-roundness does not exceed
0.025 mm (0.001 inch), the cylinder bore can be
honed. If the cylinder bore taper or out-of-round con-
dition exceeds these maximum limits, the cylinder
must be bored and then honed to accept an oversize
piston. A slight amount of taper always exists in the
cylinder bore after the engine has been in use for a
period of time.
HONINGÐCYLINDER BORE
The honing operation should be closely coordinated
with the fitting of pistons and rings. This will ensure
specified clearances are maintained.
Refer to Standard Service Procedures in the begin-
ning of this Group for the proper honing of cylinder
bores.
ASSEMBLY
Refer to the applicable sections for detailed instruc-
tions.
(1) Install the crankshaft.
(2) Install the connecting rods and the pistons
through the top of the cylinder bores.
(3) Install the front and rear oil galley plugs.
(4) Install the timing chain tensioner.
(5) Install the camshaft.
(6) Install the sprockets and chain as an assembly.
(7) Install the oil slinger to the crankshaft.
(8) Install the timing chain bumper.
(9) Install the timing case cover seal.
(10) Install the timing case cover.
(11) Install the oil pan gasket and oil pan.
(12) Install the vibration damper.
(13) Install the water pump. Tighten the mounting
bolts to 31 Nzm (270 in. lbs.) torque.
(14) Remove the distributor from the cylinder
block.
(15) Lubricate the oil filter seal with clean engine
oil. Tighten oil filter to 18 Nzm (13 ft. lbs.) torque.
(16) Install the engine into the vehicle.
(17) Fill the engine with clean lubrication oil (re-
fer to Group 0, Lubrication and Maintenance).
(18) Fill the cooling system (refer to Group 7, Cool-
ing System for the proper procedures).
Fig. 12 Cylinder Bore Measurement
9 - 46 2.5L ENGINEJ

(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

(20) Disconnect the coolant hoses from the rear of
the intake manifold and thermostat housing.
(21) Remove the fan shroud screws.
(22) Remove the radiator attaching bolts.
(23) Remove the radiator and fan shroud (Fig. 19).
Refer to Group 7, Cooling System for the proper pro-
cedure.
(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 (Fig. 19):
(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 starter motor.
(30) Remove the flywheel housing access cover.
(31) Remove the engine support cushion-to-bracket
through bolts.
(32) Disconnect the exhaust pipe from the mani-
fold.
(33) Remove the upper flywheel housing bolts and
loosen the bottom bolts.
(34) Lower the vehicle.
(35) Attach a lifting device to the engine.
(36) Raise the engine off the front supports.
(37) Place a support stand under the flywheel
housing.
(38) Remove the remaining flywheel housing bolts.(39) Lift the engine out of the engine compartment
and install on an engine stand.
INSTALLATION
(1) 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.
(2) Insert the transmission shaft into the clutch
spline.
(3) Align the flywheel housing with the engine.
(4) Install and finger tighten the flywheel housing
lower bolts.
(5) Install the engine support cushions (if re-
moved).
(6) Remove the support stand from beneath the fly-
wheel housing.
(7) Lower the engine and engine support cushions
onto the engine compartment brackets. Ensure that
the bolt holes are aligned. Install the bolts and
tighten the nuts.
(8) Remove the engine lifting device.
(9) Raise the vehicle.
(10) Attach the exhaust pipe to the manifold. In-
stall and tighten the nuts to 31 Nzm (23 ft. lbs.)
torque.
(11) Install the flywheel housing access cover.
(12) Install the remaining flywheel housing bolts.
Tighten the bolts to 38 Nzm (28 ft. lbs.) torque.
(13) Install the starter motor and connect the ca-
ble. Tighten the bolts to 45 Nzm (33 ft. lbs.) torque.
(14) Lower the vehicle.
(15) Connect the coolant hoses and tighten the
clamps.
(16) Remove the pulley-to-water pump flange
alignment capscrew and install the fan and spacer or
Tempatrol fan assembly.
Fig. 18 Fuel Line Quick-Connect Couplings, Air
Cleaner Assembly, Throttle & Speed Control CablesFig. 19 Upper Radiator Hose, Coolant Recovery
Hose, Fan Shroud & Power Steering Pump
9 - 58 4.0L ENGINEJ