coolant JEEP CHEROKEE 1994 Service Manual PDF
[x] Cancel search | Manufacturer: JEEP, Model Year: 1994, Model line: CHEROKEE, Model: JEEP CHEROKEE 1994Pages: 1784, PDF Size: 77.09 MB
Page 856 of 1784

(a) Disconnect the power steering 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 material from entering the
system.
(21) Disconnect the coolant hoses from the rear of
the intake manifold.
(22) Identify, tag and disconnect all necessary wire
connectors and vacuum hoses.
(23) Raise the vehicle.
(24) Remove the oil filter.
(25) Remove the starter motor.
(26) Disconnect the exhaust pipe from the exhaust
manifold.
(27) Remove the flywheel/converter housing access
cover.
(28) If equipped with an automatic transmission,
mark the converter and drive plate location in refer-
ence to each other and remove the converter-to-drive
plate bolts.(29) Remove the upper flywheel/converter housing
bolts and loosen the bottom bolts.
(30) Remove the engine support cushion-to-engine
compartment bracket bolts.
(31) Remove the engine shock damper bracket
from the sill.
(32) Lower the vehicle.
(33) Attach a lifting device to the engine.
(34) Raise the engine slightly off the front sup-
ports.
(35) Place a support stand under the converter or
flywheel housing.
(36) Remove the remaining bottom converter or
flywheel housing bolts.
(37) Lift the engine out of the engine compartment
and install on an engine stand.
(38) 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) If equipped with a manual transmission:
(a) Insert the transmission shaft into the clutch
spline.
(b) Align the flywheel housing with the engine.
(c) Install and tighten the flywheel housing
lower bolts finger tight.
(4) If equipped with an automatic transmission:
Fig. 16 Heater Hoses (LH Drive Vehicles), Throttle
Linkage & Quick-Connect Fuel Lines
Fig. 17 Heater Hoses (RH Drive Vehicle)
Fig. 18 Air Cleaner and Power Steering Pump
J2.5L ENGINE 9 - 15
Page 857 of 1784

(a) Align the transmission torque converter
housing with the engine.
(b) Loosely install the converter housing lower
bolts and install the next higher bolt and nut on
each side.
(c) Tighten all 4 bolts finger-tight.
(5) Install the engine support cushions (if re-
moved).
(6) Lower the engine and engine support cushions
onto the engine compartment brackets.
(7) Remove the engine lifting device.
(8) Raise the vehicle.
(9) If equipped with an automatic transmission:
(a) Install the converter-to-drive plate bolts. En-
sure the installation reference marks are aligned.
Tighten the bolts to 54 Nzm (40 ft. lbs.) torque.
(b) Install the converter-housing access cover.
(c) Install the exhaust pipe support.
(10) Install the remaining converter or flywheel
housing bolts.
(11) Install the starter motor and connect the ca-
ble. Tighten the bolts to 45 Nzm (33 ft. lbs.) torque.
(12) Tighten the engine support cushing through-
bolt nuts.
(13) Install the remaining flywheel/converter hous-
ing bolts. Tighten the bolts to 38 Nzm (28 ft. lbs.)
torque.
(14) Connect the exhaust pipe to the manifold.
(15) Install the oil filter.
(16) Lower the vehicle.
(17) Connect the coolant hoses and tighten the
clamps.
(18) If equipped with power steering:
(a) Remove the protective caps
(b) Connect the hoses to the fittings at the steer-
ing gear. Tighten the nut to 52 Nzm (38 ft. lbs.)
torque.
(c) Fill the pump reservoir with fluid.
(19) Remove the pulley-to-water pump flange
alignment capscrew and install the fan and spacer or
Tempatrol fan assembly.
(20) Install the fan shroud and radiator/condenser
(if equipped with air conditioning).
(21) Connect the radiator hoses.
(22) Connect the automatic transmission fluid
cooler pipes, if equipped.
(23) Connect the oxygen sensor wire connector.
(24) Connect the throttle valve rod and retainer.
Connect the throttle cable and install the rod. Install
the throttle valve rod spring.
(25) Connect the speed control cable, if equipped.
(26) Connect the fuel supply and return lines to
the throttle body.
(27) Connect all the vacuum hoses and wire con-
nectors.
(28) Connect the service valves to the A/C com-
pressor ports, if equipped with air conditioning.(29) Fill the power steering reservoir.
(30) Connect the battery cables.
(31) Install the hood.
(32) Install the air cleaner.
(33) Start the engine and inspect for leaks.
(34) Fill the cooling system.
(35) Stop the engine and check the fluid levels.
Add fluid, as required.
ENGINE ASSEMBLYÐYJ VEHICLES
REMOVAL
(1) Place a protective cloth over the windshield
frame. Raise the hood and rest it on the windshield
frame (Fig. 19).
(2) Disconnect the battery cable clamps and re-
move the battery.
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) 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.
Fig. 19 Hood on Windshield Frame
9 - 16 2.5L ENGINEJ
Page 858 of 1784

(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
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(14) Install the remaining flywheel housing bolts.
Tighten the bolts to 38 Nzm (28 ft. lbs.) torque.
(15) Install the starter motor and connect the ca-
ble. Tighten the bolts to 45 Nzm (33 ft. lbs.) torque.
(16) Install the oil filter.
(17) Lower the vehicle.
(18) Connect the coolant hoses and tighten the
clamps.
(19) If equipped with power steering:
(a) Remove the protective caps
(b) Connect the hoses to the fittings at the steer-
ing gear. Tighten the nut to 52 Nzm (38 ft. lbs.)
torque.
(c) Fill the pump reservoir with fluid.
(20) Remove the pulley-to-water pump flange
alignment capscrew and install the fan and spacer or
Tempatrol fan assembly.
(21) Tighten the serpentine drive belt according to
the specifications listed in Group 7, Cooling System.
(22) Install the fan shroud and radiator.
(23) Connect the radiator hoses.
(24) Connect the heater hoses.
(25) Connect the throttle valve rod and retainer.
(26) Connect the throttle cable and install the rod.
(27) Install the throttle valve rod spring.
(28) Connect the speed control cable, if equipped.
(29) Connect the oxygen sensor wire connector.
(30) Install the vacuum hose and check valve on
the brake booster.
(31) Connect the coolant temperature sensor wire
connector.
(32) Connect the idle speed actuator wire connec-
tor.
(33) Connect the fuel inlet and return hoses at the
fuel rail. Verify that the quick-connect fitting assem-
bly fits securely over the fuel lines by giving the fuel
lines a firm tug.
(34) Install the fuel line bracket to the intake
manifold.
(35) Connect all fuel injection wire connections.
(36) Install the engine ground strap.
(37) Connect the ignition coil wire connector.
(38) Remove the coolant temperature sending unit
to permit air to escape from the block. Fill the cool-
ing system with coolant. Install the coolant tempera-
ture sending unit when the system is filled.
(39) Install the battery and connect the battery ca-
bles.
(40) Install the air cleaner bonnet to the throttle
body.
(41) Install the air cleaner.
(42) Lower the hood and secure in place.
(43) Start the engine and inspect for leaks.
(44) Stop the engine and check the fluid levels.
Add fluid, as required.ENGINE CYLINDER HEAD COVER
A cured gasket is part of the engine cylinder head
cover.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Disconnect the Crankcase Ventilation (CCV)
vacuum hose from engine cylinder head cover (Fig.
1).
(3) Disconnect the fresh air inlet hose from the en-
gine cylinder head cover (Fig. 1).
(4) Remove the engine cylinder head cover mount-
ing bolts.
(5) Remove the engine cylinder head cover.
CLEANING
Remove any original sealer from the cover sealing
surface of the engine cylinder head and clean the
surface using a fabric cleaner.
Remove all residue from the sealing surface using
a clean, dry cloth.
INSPECTION
Inspect the engine cylinder head cover for cracks.
Replace the cover, if cracked.
The original grey gasket material should NOT be
removed. If sections of the gasket material are miss-
ing or are compressed, replace the engine cylinder
head cover. However, sections with minor damage
such as small cracks, cuts or chips may be repaired
with a hand held applicator. The new material must
be smoothed over to maintain gasket height. Allow
the gasket material to cure prior to engine cylinder
head cover installation.
INSTALLATION
(1) If a replacement cover is installed, transfer the
CCV valve grommet the oil filler cap from the origi-
nal cover to the replacement cover.
(2) Install engine cylinder head cover. Tighten the
mounting bolts to 10 Nzm (85 in. lbs.) torque.
Fig. 1 Engine Cylinder Head Cover
9 - 18 2.5L ENGINEJ
Page 860 of 1784

(3) Connect the CCV hoses (Fig. 1).
(4) Connect negative cable to battery.
ROCKER ARMS
This procedure can be done with the engine in or
out of the vehicle.
REMOVAL
(1) Remove the engine cylinder head cover.
(2) Remove the capscrews at each bridge and pivot
assembly (Fig. 2). Alternately loosen the capscrews
one turn at a time to avoid damaging the bridges.
(3) Check for rocker arm bridges which are caus-
ing misalignment of the rocker arm to valve tip area.
(4) Remove the bridges, pivots and corresponding
pairs of rocker arms (Fig. 2). Place them on a bench
in the same order as removed.
(5) Remove the push rods and place them on a
bench in the same order as removed.
CLEANING
Clean all the components with cleaning solvent.
Use compressed air to blow out the oil passages in
the rocker arms and push rods.
INSPECTION
Inspect the pivot surface area of each rocker arm.
Replace any that are scuffed, pitted, cracked or ex-
cessively worn.
Inspect the valve stem tip contact surface of each
rocker arm and replace any rocker arm that is deeply
pitted.
Inspect each push rod end for excessive wear and
replace as required. If any push rod is excessivelyworn because of lack of oil, replace it and inspect the
corresponding hydraulic tappet for excessive wear.
Inspect the push rods for straightness by rolling
them on a flat surface or by shining a light between
the push rod and the flat surface.
A wear pattern along the length of the push rod is
not normal. Inspect the engine cylinder head for ob-
struction if this condition exists.
INSTALLATION
(1) Lubricate the ball ends of the push rods with
Mopar Engine Oil Supplement, or equivalent and in-
stall push rods in their original locations. Ensure
that the bottom end of each push rod is centered in
the tappet plunger cap seat.
(2) Using Mopar Engine Oil Supplement, or equiv-
alent, lubricate the area of the rocker arm that the
pivot contacts. Install rocker arms, pivots and bridge
above each cylinder in their originally position.
(3) Loosely install the capscrews through each
bridge.
(4) At each bridge, tighten the capscrews alter-
nately, one turn at a time, to avoid damaging the
bridge. Tighten the capscrews to 28 Nzm (21 ft. lbs.)
torque.
(5) Install the engine cylinder head cover.
ENGINE CYLINDER HEAD
This procedure can be done with the engine in or
out of the vehicle.
REMOVAL
(1) Disconnect negative cable from battery.
WARNING: DO NOT REMOVE THE CYLINDER
BLOCK DRAIN PLUGS OR LOOSEN THE RADIATOR
DRAIN COCK WITH THE SYSTEM HOT AND PRES-
SURIZED BECAUSE SERIOUS BURNS FROM THE
COOLANT CAN OCCUR.
(2) Drain the coolant and disconnect the hoses at
the engine thermostat housing. DO NOT waste reus-
able coolant. If the solution is clean and is being
drained only to service the engine or cooling system,
drain the coolant into a clean container for reuse.
(3) Remove the air cleaner assembly.
(4) Remove the engine cylinder head cover.
(5) Remove the capscrews, bridge and pivot assem-
blies and rocker arms (Fig. 2).
(6) Remove the push rods (Fig. 2).Retain the
push rods, bridges, pivots and rocker arms in
the same order as removed.
(7) Loosen the serpentine drive belt at the power
steering pump, if equipped or at the idler pulley (re-
fer to Group 7, Cooling System for the proper proce-
dure).
(8) If equipped with air conditioning, perform the
following:
Fig. 2 Rocker Arm Assembly
J2.5L ENGINE 9 - 19
Page 861 of 1784

(a) Remove the bolts from the A/C compressor
mounting bracket and set the compressor aside.
(b) Remove the air conditioner compressor
bracket bolts from the engine cylinder head.
(c) Loosen the through bolt at the bottom of the
bracket.
(9) If equipped, disconnect the power steering
pump bracket. Set the pump and bracket aside. DO
NOT disconnect the hoses.
(10) Remove the fuel lines and vacuum advance
hose.
(11) Remove the intake and engine exhaust mani-
folds from the engine cylinder head (refer to Group
11, Exhaust System and Intake Manifold for the
proper procedures).
(12) Disconnect the ignition wires and remove the
spark plugs.
(13) Disconnect the temperature sending unit wire
connector.
(14) Remove the ignition coil and bracket assem-
bly.
(15) Remove the engine cylinder head bolts.
(16) Remove the engine cylinder head and gasket
(Fig. 3).
(17) If this was the first time the bolts were re-
moved, put a paint dab on the top of the bolt. If the
bolts have a paint dab on the top of the bolt or it
isn't known if they were used before, discard the
bolts.
(18) Stuff clean lint free shop towels into the cyl-
inder bores.
CLEANING
Thoroughly clean the engine cylinder head and cyl-
inder block mating surfaces. Clean the intake and
exhaust manifold and engine cylinder head mating
surfaces. Remove all gasket material and carbon.
Check to ensure that no coolant or foreign material
has fallen into the tappet bore area.
Remove the carbon deposits from the combustion
chambers and top of the pistons.
INSPECTION
Use a straightedge and feeler gauge to check the
flatness of the engine cylinder head and block mat-
ing surfaces.
INSTALLATION
The engine cylinder head gasket is a composition
gasket. The gasket is to be installed DRY.DO NOT
use a gasket sealing compound on the gasket.
If the engine cylinder head is to be replaced and
the original valves used, measure the valve stem di-
ameter. Only standard size valves can be used with a
service replacement engine cylinder head unless the
replacement head valve stem guide bores are reamed
to accommodate oversize valve stems. Remove all
carbon buildup and reface the valves.
(1) Fabricate two engine cylinder head alignment
dowels from used head bolts (Fig. 4). Use the longest
head bolt. Cut the head of the bolt off below the hex
head. Then cut a slot in the top of the dowel to allow
easier removal with a screwdriver.
(2) Install one dowel in bolt hole No.10 and the
other dowel in bolt hole No.8 (Fig. 5).
(3) Remove the shop towels from the cylinder
bores. Coat the bores with clean engine oil.
(4) Place the engine cylinder head gasket (with the
numbers facing up) over the dowels.
Fig. 3 Engine Cylinder Head Assembly
Fig. 4 Fabricate Alignment Dowels
Fig. 5 Alignment Dowel Locations
9 - 20 2.5L ENGINEJ
Page 862 of 1784

(5) Place the engine cylinder head over the dowels.
CAUTION: Engine cylinder head bolts should be re-
used only once. Replace the head bolts if they were
used before or if they have a paint dab on the top
of the bolt.
(6) Coat the threads of bolt No.7, only, with Loctite
PST sealant or equivalent.
(7) Install all head bolts, except No.8 and No.10.
(8) Remove the dowels.
(9) Install No.8 and No.10 head bolts.
(10) Tighten the engine cylinder head bolts in se-
quence according to the following procedure (Fig. 6):
(a) Tighten all bolts in sequence (1 through 10)
to 30 Nzm (22 ft. lbs.) torque.
(b) Tighten all bolts in sequence (1 through 10)
to 61 Nzm (45 ft. lbs.) torque.
(c) Check all bolts to verify they are set to 61
Nzm (45 ft. lbs.) torque.
(d) Tighten bolts (in sequence):
²Bolts 1 through 6 to 149 Nzm (110 ft. lbs.) torque.
²Bolt 7 to 136 Nzm (100 ft. lbs.) torque.
²Bolts 8 through 10 to 149 Nzm (110 ft. lbs.) torque.
CAUTION: During the final tightening sequence,
bolt No.7 will be tightened to a lower torque than
the rest of the bolts. DO NOT overtighten bolt No.7.
(e) Check all bolts in sequence to verify the cor-
rect torque.
(f) If not already done, clean and mark each bolt
with a dab of paint after tightening. Should you
encounter bolts which were painted in an earlier
service operation, replace them.
(11) Install the ignition coil and bracket assembly.
(12) Connect the temperature sending unit wire
connector.
(13) Install the spark plugs and tighten to 37 Nzm
(27 ft. lbs.) torque. Connect the ignition wires.(14) Install the intake and exhaust manifolds (re-
fer to Group 11, Exhaust System and Intake Mani-
fold for the proper procedures).
(15) Install the fuel lines and the vacuum advance
hose.
(16) If equipped, attach the power steering pump
and bracket.
(17) Install the push rods, rocker arms, pivots and
bridges in the order they were removed.
(18) Install the engine cylinder head cover.
(19) Attach the air conditioning compressor mount-
ing bracket to the engine cylinder head and block.
Tighten the bolts to 40 Nzm (30 ft. lbs.) torque.
(20) Attach the air conditioning compressor to the
bracket. Tighten the bolts to 27 Nzm (20 ft. lbs.)
torque.
CAUTION: The serpentine drive belt must be routed
correctly. Incorrect routing can cause the water
pump to turn in the opposite direction causing the
engine to overheat.
(21) Install the serpentine drive belt and correctly
tension the belt (refer to Group 7, Cooling System for
the proper procedure).
(22) Install the air cleaner and ducting.
(23) Install the engine cylinder head cover.
(24) Connect the hoses to the thermostat housing
and fill the cooling system to the specified level (re-
fer to Group 7, Cooling Systems for the proper proce-
dure).
(25) The automatic transmission throttle linkage
and cable must be adjusted after completing the en-
gine cylinder head installation (refer to Group 21,
Transmissions for the proper procedures).
(26) Install the temperature sending unit and con-
nect the wire connector.
(27) Connect the fuel pipe and vacuum advance
hose.
(28) Connect negative cable to battery.
(29) Connect the upper radiator hose and heater
hose at the thermostat housing.
(30) Fill the cooling system. Check for leaks.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN DIRECT
LINE WITH THE FAN. DO NOT PUT HANDS NEAR
THE PULLEYS, BELTS OR FAN. DO NOT WEAR
LOOSE CLOTHING.
(31) Operate the engine with the radiator cap off.
Inspect for leaks and continue operating the engine
until the thermostat opens. Add coolant, if required.
VALVE SPRINGS AND OIL SEALS
This procedure can be done with the engine cylin-
der head installed on the block.
Fig. 6 Engine cylinder head Bolt Tightening
Sequence
J2.5L ENGINE 9 - 21
Page 864 of 1784

INSPECTION
Inspect for cracks in the combustion chambers and
valve ports.
Inspect for cracks on the exhaust seat.
Inspect for cracks in the gasket surface at each
coolant passage.
Inspect valves for burned, cracked or warped heads.
Inspect for scuffed or bent valve stems.
Replace valves displaying any damage.
VALVE REFACING
(1) Use a valve refacing machine to reface the in-
take and exhaust valves to the specified angle.
(2) After refacing, a margin of at least 0.787 mm
(0.031 inch) must remain (Fig. 8). If the margin is
less than 0.787 mm (0.031 inch), the valve must be
replaced.
VALVE SEAT REFACING
(1) Install a pilot of the correct size in the valve
guide bore. Reface the valve seat to the specified an-
gle with a good dressing stone. Remove only enough
metal to provide a smooth finish.
(2) Use tapered stones to obtain the specified seat
width when required.
(3) Control valve seat runout to a maximum of
0.0635 mm (0.0025 in.)Ð(Fig. 9).
VALVE STEM OIL SEAL REPLACEMENT
Valve stem oil seals are installed on each valve
stem to prevent rocker arm lubricating oil from en-
tering the combustion chamber through the valve
guide bores. One seal is marked INT (intake valve)
and the other is marked EXH (exhaust valve).Replace the oil seals whenever valve service is per-
formed or if the seals have deteriorated.
VALVE GUIDES
The valve guides are an integral part of the engine
cylinder head and are not replaceable.
When the valve stem guide clearance is excessive,
the valve guide bores must be reamed oversize. Ser-
vice valves with oversize stems are available in 0.076
mm (0.003 inch) and 0.381 mm (0.015 inch) incre-
ments.
Corresponding oversize valve stem seals are also
available and must be used with valves having 0.381
mm (0.015 inch) oversize stems.
If the valve guides are reamed oversize, the
valve seats must be ground to ensure that the
valve seat is concentric to the valve guide.
VALVE STEM-TO-GUIDE CLEARANCE
MEASUREMENT
Valve stem-to-guide clearance may be measured by
either of the following two methods.
PREFERRED METHOD:
(1) Remove the valve from the head.
(2) Clean the valve stem guide bore with solvent
and a bristle brush.
(3) Insert a telescoping gauge into the valve stem
guide bore approximately 9.525 mm (.375 inch) from
the valve spring side of the head (Fig. 10).
(4) Remove and measure telescoping gauge with a
micrometer.
(5) Repeat the measurement with contacts length-
wise to engine cylinder head.
(6) Compare the crosswise to lengthwise measure-
ments to determine out-of-roundness. If the measure-
ments differ by more than 0.0635 mm (0.0025 in.),
ream the guide bore to accommodate an oversize
valve stem.
Fig. 8 Valve Facing Margin
Fig. 9 Measurement of Valve Seat Runout
J2.5L ENGINE 9 - 23
Page 870 of 1784

(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
Page 872 of 1784

CAMSHAFT PIN REPLACEMENT
REMOVAL
WARNING: DO NOT LOOSEN THE RADIATOR
DRAIN COCK WITH THE SYSTEM HOT AND PRES-
SURIZED BECAUSE SERIOUS BURNS FROM COOL-
ANT CAN OCCUR.
(1) Disconnect negative cable from battery.
(2) Drain the radiator. DO NOT waste reusable
coolant. Drain the coolant into a clean container.
(3) Remove the fan and shroud.
(4) Disconnect the radiator overflow tube, radiator
hoses, automatic transmission fluid cooler pipes (if
equipped).
(5) Remove the radiator.
(6) If equipped with air conditioning:
CAUTION: DO NOT loosen or disconnect any air
conditioner system fittings. Move the condenser
and receiver/drier aside as a complete assembly.
(a) Remove the A/C compressor serpentine drive
belt idler pulley.
(b) Disconnect and remove the generator.
(c) Remove the A/C condenser attaching bolts
and move the condenser and receiver/drier assem-
bly up and out of the way.
(7) Remove the serpentine drive belt.
(8) Remove the crankshaft vibration damper.
(9) Remove the timing case cover. Clean the gas-
ket material from the cover.
(10) Rotate crankshaft until the crankshaft
sprocket timing mark is closest to and on the center
line with the camshaft sprocket timing mark (Fig.
15).
(11) Remove camshaft sprocket retaining bolt.
(12) Remove the crankshaft oil slinger.
(13) Remove the sprockets and chain as an assem-
bly (Fig. 16).CAUTION: The following procedural step must be
accomplished to prevent the camshaft from damag-
ing the rear camshaft plug during pin installation.
(14) Inspect the damaged camshaft pin.
(15) If the pin is a spring-type pin, remove the bro-
ken pin by inserting a self-tapping screw into the pin
and carefully pulling the pin from the camshaft.
(16) If the pin is a dowel-type pin, center-punch it.
Ensure the exact center is located when center-
punching the pin.
CAUTION: Cover the opened oil pan area to prevent
metal chips from entering the pan.
(17) Drill into the pin center witha4mm(5/32
inch) drill bit.
(18) Insert a self-tapping screw into the drilled pin
and carefully pull the pin from the camshaft.
CAMSHAFT BEARINGS
The camshaft rotates within four steel-shelled, bab-
bitt-lined bearings that are pressed into the cylinder
block and then line reamed. The camshaft bearing
bores and bearing diameters are not the same size.
They are stepped down in 0.254 mm (0.010 inch) in-
crements from the front bearing (largest) to the rear
bearing (smallest). This permits easier removal and
installation of the camshaft. The camshaft bearings
are pressure lubricated.
It is not advisable to attempt to replace cam-
shaft bearings unless special removal and instal-
lation tools are available.
Camshaft end play is maintained by the load
placed on the camshaft by the oil pump and distrib-
utor drive gear. The helical cut of the gear holds the
camshaft sprocket thrust face against the cylinder
block face.
Fig. 15 Timing Chain Alignment
Fig. 16 Camshaft and Crankshaft Sprocket and
Chain
J2.5L ENGINE 9 - 31