2002 JEEP LIBERTY seats

(6) Position the camshaft drive gear into the tim-
ing chain aligning the V6 mark between the two
marked chain links (Two links marked during remov-
al).
(7) Using Special Tool 8428 Camshaft Wrench,
rotate the camshaft until the camshaft sprocket
dowel is aligned with the slot in the camshaft
sprocket. Install the sprocket onto the camshaft.
CAUTION: Remove excess oil from camshaft
sprocket bolt. Failure to do so can cause bolt over-
torque resulting in bolt failure.
(8) Remove excess oil from camshaft sprocket bolt,
then install the camshaft sprocket retaining bolt and
hand tighten.
(9) Remove timing chain wedge special tool 8379.
(10) Using Special Tool 6958 spanner wrench with
adapter pins 8346, torque the camshaft sprocket
retaining bolt to 122 N´m (90 ft. lbs.).
(11) Install the camshaft position sensor.
(12) Install the cylinder head cover.
CYLINDER HEAD COVER(S)
REMOVAL
(1) Disconnect battery negative cable.
(2) Remove air cleaner assembly, resonator assem-
bly and air inlet hose.
(3) Drain cooling system, below the level of the
heater hoses. Refer to COOLING SYSTEM.(4) Remove accessory drive belt.
(5) Remove air conditioning compressor retaining
bolts and move compressor to the left.
(6) Remove heater hoses.
(7) Disconnect injector and ignition coil connectors.
(8) Disconnect and remove positive crankcase ven-
tilation (PCV) hose.
(9) Remove oil fill tube.
(10) Un-clip injector and ignition coil harness and
move away from cylinder head cover.
(11) Remove right rear breather tube and filter
assembly.
(12) Remove cylinder head cover retaining bolts.
(13) Remove cylinder head cover.
INSTALLATION
CAUTION: Do not use harsh cleaners to clean the
cylinder head covers. Severe damage to covers
may occur.
NOTE: The gasket may be used again, provided no
cuts, tears, or deformation has occurred.
(1) Clean cylinder head cover and both sealing sur-
faces. Inspect and replace gasket as necessary.
(2) Tighten cylinder head cover bolts and double
ended studs to 12 N´m (105 in. lbs).
(3) Install right rear breather tube and filter
assembly.
(4) Connect injector, ignition coil electrical connec-
tors and harness retaining clips.
(5) Install the oil fill tube.
(6) Install PCV hose.
(7) Install heater hoses.
(8) Install air conditioning compressor retaining
bolts.
(9) Install accessory drive belt
(10) Fill Cooling system
(11) Install air cleaner assembly, resonator assem-
bly and air inlet hose.
(12) Connect battery negative cable.
INTAKE/EXHAUST VALVES &
SEATS
STANDARD PROCEDURE - REFACING
NOTE: Valve seats that are worn or burned can be
reworked, provided that correct angle and seat
width are maintained. Otherwise the cylinder head
must be replaced.
Fig. 23 Camshaft Bearing Caps Tightening
Sequence
9 - 34 ENGINE - 3.7LKJ
CAMSHAFT(S) (Continued)

NOTE: When refacing valves and valve seats, it is
important that the correct size valve guide pilot be
used for reseating stones. A true and complete sur-
face must be obtained.
(1) Using a suitable dial indicator measure the
center of the valve seat Total run out must not
exceed 0.051 mm (0.002 in).
(2) Apply a small amount of Prussian blue to the
valve seat, insert the valve into the cylinder head,
while applying light pressure on the valve rotate the
valve. Remove the valve and examine the valve face.
If the blue is transferred below the top edge of the
valve face, lower the valve seat using a 15 degree
stone. If the blue is transferred to the bottom edge of
the valve face, raise the valve seat using a 65 degree
stone.
(3) When the seat is properly positioned the width
of the intake seat must be 1.75 ± 2.36 mm (0.0689 ±
0.0928 in.) and the exhaust seat must be 1.71 ± 2.32
mm (0.0673 ± 0.0911 in.).
(4) Check the valve spring installed height after
refacing the valve and seat. The installed height for
both intake and exhaust valve springs must not
exceed 41.44 mm (1.6315 in.).
(5) The valve seat and valve face must maintain a
face angle of 44.5 ± 45 degrees angle (Fig. 24).REMOVAL
NOTE: The cylinder heads must be removed in
order to perform this procedure.
(1) Remove rocker arms and lash adjusters. Refer
to procedures in this section (Fig. 25).
(2) Remove the camshaft bearing caps and the
camshaft.
NOTE: All six valve springs and valves are removed
in the same manner; this procedure only covers
one valve and valve spring.
(3) Using Special Tool C-3422±B or C-3422±C
Valve Spring Compressor and Special tool 8519
Adapter, compress the valve spring.
NOTE: It may be necessary to tap the top of the
valve spring to loosen the spring retainers locks
enough to be removed.
(4) Remove the two spring retainer lock halves.
NOTE: the valve spring is under tension use care
when releasing the valve spring compressor.
(5) Remove the valve spring compressor.
(6) Remove the spring retainer, and the spring.
Fig. 24 Valve Assembly Configuration
1 - VALVE LOCKS (3±BEAD)
2 - RETAINER
3 - VALVE STEM OIL SEAL
4 - INTAKE VALVE
5 - EXHAUST VALVE
6 - VALVE SPRING
Fig. 25 Rocker Arm Removal
1 - CAMSHAFT
2 - SPECIAL TOOL 8516
KJENGINE - 3.7L 9 - 35
INTAKE/EXHAUST VALVES & SEATS (Continued)

NOTE: Check for sharp edges on the keeper
grooves. Remove any burrs from the valve stem
before removing the valve from the cylinder head.
(7) Remove the valve from the cylinder head.
NOTE: The valve stem seals are common between
intake and exhaust.
(8) Remove the valve stem seal. Mark the valve for
proper installation.
TESTING VALVE SPRINGS
NOTE: Whenever the valves are removed from the
cylinder head it is recommended that the valve
springs be inspected and tested for reuse.
Inspect the valve springs for physical signs of wear
or damage. Turn table of tool C-647 until surface is
in line with the 40.69 mm (1.602 in.) mark on the
threaded stud and the zero mark on the front. Place
spring over the stud on the table and lift compress-
ing lever to set tone device. Pull on torque wrench
until Ping is heard. Take reading on torque wrench
at this instant. Multiply this reading by two. This
will give the spring load at test length. Fractional
measurements are indicated on the table for finer
adjustments. Refer to Specifications Section to obtain
specified height and allowable tensions. Replace any
springs that do not meet specifications (Fig. 26).
INSTALLATION
(1) coat the valve stem with clean engine oil and
insert it into the cylinder head.
(2) Install the valve stem seal. make sure the seal
is fully seated and that the garter spring at the top
of the seal is intact.
(3) Install the spring and the spring retainer.
(4) Using the valve spring compressor, compress
the spring and install the two valve spring retainer
halves (Fig. 27).
(5) Release the valve spring compressor and make
sure the two spring retainer halves and the spring
retainer are fully seated.
(6) lubricate the camshaft journal with clean
engine oil then Position the camshaft (with the
sprocket dowel on the left camshaft at 11 o'clock and
the right camshaft at 12 o'clock), then position the
camshaft bearing caps.
(7) Install the camshaft bearing cap retaining
bolts. Tighten the bolts 9±13 N´m (100 in. lbs.) in ó
turn increments in the sequence shown (Fig. 28).
(8) Position the hydraulic lash adjusters and
rocker arms.
Fig. 26 Testing Valve Springs
1 - SPECIAL TOOL C-647
Fig. 27 Valve Assembly Configuration
1 - VALVE LOCKS (3±BEAD)
2 - RETAINER
3 - VALVE STEM OIL SEAL
4 - INTAKE VALVE
5 - EXHAUST VALVE
6 - VALVE SPRING
9 - 36 ENGINE - 3.7LKJ
INTAKE/EXHAUST VALVES & SEATS (Continued)

ROCKER ARM
DESCRIPTION
The rocker arms are steel stampings with an inte-
gral roller bearing. The rocker arms incorporate a 2.8
mm (0.11 inch) oil hole in the lash adjuster socket for
roller and camshaft lubrication.
REMOVAL
NOTE: Disconnect the battery negative cable to pre-
vent accidental starter engagement.
(1) Remove the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(2) For rocker arm removal on cylinder #4, Rotate
the crankshaft until cylinder #1 is at TDC exhaust
stroke.
(3) For rocker arm removal on cylinder #1, Rotate
the crankshaft until cylinder #1 is at TDC compres-
sion stroke.
(4) For rocker arm removal on cylinders #2 and #3,
Rotate the crankshaft until cylinder #1 is at BDC
compression stroke.
(5) For rocker arm removal on cylinders #5 and #6,
Rotate the crankshaft until cylinder #1 is at BDC
exhaust stroke.
(6) Using special tool 8516 Rocker Arm Remover,
press downward on the valve spring, remove rocker
arm (Fig. 29).
INSTALLATION
CAUTION: Make sure the rocker arms are installed
with the concave pocket over the lash adjusters.
Failure to do so may cause severe damage to the
rocker arms and/or lash adjusters.
NOTE: Coat the rocker arms with clean engine oil
prior to installation.
(1) For rocker arm installation on cylinders #4,
Rotate the crankshaft until cylinder #1 is at TDC
exhaust stroke.
(2) For rocker arm installation on cylinder #1,
Rotate the crankshaft until cylinder #1 is at TDC
compression stroke.
(3) For rocker arm installation on cylinders #2 and
#3, Rotate the crankshaft until cylinder #1 is at BDC
compression stroke.
(4) For rocker arm installation on cylinders #5 and
#6, Rotate the crankshaft until cylinder #1 is at BDC
exhaust stroke.
(5) Using special tool 8516 press downward on the
valve spring, install rocker arm (Fig. 30).
(6) Install the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
Fig. 28 Camshaft Bearing Caps Tightening
SequenceFig. 29 Rocker Arm - Removal
1 - CAMSHAFT
2 - SPECIAL TOOL 8516
KJENGINE - 3.7L 9 - 37
INTAKE/EXHAUST VALVES & SEATS (Continued)

CRANKSHAFT OIL SEAL -
REAR
REMOVAL
NOTE: This procedure can be performed in vehicle.
(1) If being preformed in vehicle, remove the
transmission.
(2) Remove the flexplate (Refer to 9 - ENGINE/
ENGINE BLOCK/FLEX PLATE - REMOVAL).
NOTE: The crankshaft oil seal CAN NOT be reused
after removal.
NOTE: The crankshaft rear oil seal remover Special
Tool 8506 must be installed deeply into the seal.
Continue to tighten the removal tool into the seal
until the tool can not be turned farther. Failure to
install tool correctly the first time will cause tool to
pull free of seal without removing seal from engine.
(3) Using Special Tool 8506 (Fig. 48), remove the
crankshaft rear oil seal.
INSTALLATION
(1) Position the magnetic seal guide Special Tool
8349±2 (Fig. 49) onto the crankshaft rear face. Then
position the crankshaft rear oil seal onto the guide.(2) Using Special Tools 8349 Crankshaft Rear Oil
Seal Installer and C-4171 Driver Handle (Fig. 50),
with a hammer, tap the seal into place. Continue to
tap on the driver handle until the seal installer seats
against the cylinder block crankshaft bore.
(3) Install the flexplate.
(4) Install the transmission.
Fig. 48 Crankshaft Rear Oil Seal Removal
1 - REAR CRANKSHAFT SEAL
2 - SPECIAL TOOL 8506
Fig. 49 Crankshaft Rear Oil Seal Guide Special Tool
8349±2 and Oil
1 - REAR CRANKSHAFT SEAL
2 - SPECIAL TOOL 8349±2 GUIDE
Fig. 50 Crankshaft Rear Oil Seal Installation
1 - REAR CRANKSHAFT SEAL
2 - SPECIAL TOOL 8349±1 INSTALLER
3 - SPECIAL TOOL C-4171 HANDLE
9 - 48 ENGINE - 3.7LKJ

ENGINE
TABLE OF CONTENTS
page page
ENGINE - 2.4L
DESCRIPTION..........................3
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE
TEST................................3
DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE TEST.........3
DIAGNOSIS AND TESTING - ENGINE OIL
LEAK INSPECTION.....................4
DIAGNOSIS AND TESTING - ENGINE.......5
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - PERFORMANCE............5
DIAGNOSIS AND TESTING - ENGINE
MECHANICAL.........................7
STANDARD PROCEDURE
STANDARD PROCEDURE - ENGINE CORE
AND OIL GALLERY PLUGS...............9
STANDARD PROCEDURE - REPAIR OF
DAMAGED OR WORN THREADS..........9
STANDARD PROCEDURE - HYDROSTATIC
LOCKED ENGINE......................9
STANDARD PROCEDURE - FORM-IN-
PLACE GASKETS AND SEALERS.........10
STANDARD PROCEDURE - ENGINE
GASKET SURFACE PREPARATION........11
STANDARD PROCEDURE - MEASURING
BEARING CLEARANCE USING
PLASTIGAGE.........................11
REMOVAL - ENGINE ASSEMBLY...........12
INSTALLATION - ENGINE ASSEMBLY........12
SPECIFICATIONS
SPECIFICATIONS - 2.4L ENGINE.........13
SPECIFICATIONS - TORQUE............16
SPECIAL TOOLS
2.4L ENGINE.........................17
AIR CLEANER ELEMENT
REMOVAL - 2.4L........................19
INSTALLATION - 2.4L....................19
CYLINDER HEAD
DESCRIPTION.........................19
OPERATION...........................19
DIAGNOSIS AND TESTING - CYLINDER HEAD
GASKET............................19
REMOVAL - CYLINDER HEAD.............20
CLEANING............................20
INSPECTION..........................21
INSTALLATION - CYLINDER HEAD..........21CAMSHAFT OIL SEAL(S)
REMOVAL.............................22
INSTALLATION.........................22
CAMSHAFT(S)
DESCRIPTION.........................23
OPERATION...........................23
STANDARD PROCEDURE - CAMSHAFT
END-PLAY...........................23
REMOVAL.............................24
CLEANING............................24
INSPECTION..........................25
INSTALLATION.........................25
CYLINDER HEAD COVER
REMOVAL.............................26
CLEANING............................26
INSPECTION..........................26
INSTALLATION.........................26
INTAKE/EXHAUST VALVES & SEATS
DESCRIPTION.........................27
CLEANING............................27
VALVE SPRINGS
REMOVAL
REMOVAL - CYLINDER HEAD ON.........27
REMOVAL - CYLINDER HEAD OFF........27
INSPECTION..........................28
INSTALLATION
INSTALLATION - CYLINDER HEAD ON.....28
INSTALLATION - CYLINDER HEAD OFF....28
HYDRAULIC LIFTERS
DIAGNOSIS AND TESTING - LASH ADJUSTER
(TAPPET) NOISE DIAGNOSIS............28
REMOVAL.............................29
INSTALLATION.........................29
ROCKER ARMS
REMOVAL.............................29
INSPECTION..........................30
INSTALLATION.........................30
ENGINE BLOCK
DESCRIPTION.........................30
STANDARD PROCEDURE
STANDARD PROCEDURE - PISTON TO
CYLINDER BORE FITTING..............30
STANDARD PROCEDURE - CYLINDER
BORE HONING.......................31
CLEANING............................31
INSPECTION..........................32
CONNECTING ROD BEARINGS
STANDARD PROCEDURE
CONNECTING ROD - FITTING...........32
KJENGINE 9s - 1

DIAGNOSIS AND TESTING - ENGINE MECHANICAL
CONDITION POSSIBLE CAUSES CORRECTION
NOISY VALVES 1. High or low oil level in
crankcase.1. Check and correct engine oil
level.
2. Thin or diluted oil. 2. Change oil to correct viscosity.
3. Thick oil 3. (a) Change engine oil and filter.
(b) Run engine to operating
temperature.
(c) Change engine oil and filter
again.
4. Low oil pressure. 4. Check and correct engine oil
level.
5. Dirt in tappets/lash adjusters. 5. Replace rocker arm/hydraulic
lash adjuster assembly.
6. Worn rocker arms. 6. Inspect oil supply to rocker arms.
7. Worn tappets/lash adjusters. 7. Install new rocker arm/hydraulic
lash adjuster assembly.
8. Worn valve guides. 8. Replace cylinder head assembly.
9. Excessive runout of valve seats
on valve faces.9. Grind valve seats and valves.
10. Missing adjuster pivot. 10. Replace rocker arm/hydraulic
lash adjuster assembly.
CONNECTING ROD NOISE 1. Insufficient oil supply. 1. Check engine oil level.
2. Low oil pressure. 2. Check engine oil level. Inspect oil
pump relief valve and spring.
3. Thin or diluted oil. 3. Change oil to correct viscosity.
4. Thick oil 4. (a) Change engine oil and filter.
(b) Run engine to operating
temperature.
(c) Change engine oil and filter
again.
5. Excessive bearing clearance. 5. Measure bearings for correct
clearance. Repair as necessary.
6. Connecting rod journal
out-of-round.6. Replace crankshaft or grind
surface.
7. Misaligned connecting rods. 7. Replace bent connecting rods.
KJENGINE9s-7
ENGINE - 2.4L (Continued)

AIR CLEANER ELEMENT
REMOVAL - 2.4L
Housing removal is not necessary for element (fil-
ter) replacement.
(1) Disconnect air intake duct at side of element
cover.
(2) Pry up 2 spring clips from front of housing
cover (spring clips retain cover to housing).
(3) Release housing cover from locating tabs
located on rear of housing, and remove cover.
(4) Remove air cleaner element (filter) from hous-
ing.
(5) Clean inside of housing before replacing ele-
ment.
INSTALLATION - 2.4L
(1) Install element into housing.
(2) Position housing cover into housing locating
tabs.
(3) Pry up spring clips and lock cover to housing.
(4) Connect air intake duct.
If any air filter, air resonator, air intake tubes or
air filter housing clamps had been loosened or
removed, tighten them to 5 N´m (40 in. lbs.) torque.
CYLINDER HEAD
DESCRIPTION
The cross flow designed, aluminum cylinder head
contains dual over-head camshafts with four valves
per cylinder (Fig. 5). The valves are arrange in two
in-line banks. The intake valves face toward the left
side of the vehicle. The exhaust valves face the right
side. The cylinder head incorporates powdered metalvalve guides and seats. The cylinder head is sealed to
the block using a multi-layer steel head gasket and
retaining bolts.
Integral oil galleries providing lubrication passages
to the hydraulic lash adjusters, camshafts, and valve
mechanisms.
OPERATION
The cylinder head closes the combustion chamber,
allowing the pistons to compress the fuel/air mixture
for ignition. The valves are actuated by the lobe pro-
files on the camshaft to open and close at specified
duration to either allow clean air in the combustion
chamber or the exhaust gases out; depending on the
stroke of the engine.
DIAGNOSIS AND TESTING - CYLINDER HEAD
GASKET
A cylinder head gasket leak can be located between
adjacent cylinders or between a cylinder and the
adjacent water jacket.
Possible indications of the cylinder head gasket
leaking between adjacent cylinders are:
²Loss of engine power
²Engine misfiring
²Poor fuel economy
Combustion Leak Tester C-3685-A
Cylinder Compression Pressure Adaptor 8116
Fig. 5 Cylinder Head and Camshafts
CAM PLUG - NOT SHOWN
1 - CAMSHAFT BEARING CAPS
2 - PLUG
3 - CAMSHAFT
4 - CYLINDER HEAD
5 - CAMSHAFT OIL SEAL
KJENGINE9s-19
ENGINE - 2.4L (Continued)