2002 JEEP LIBERTY vent

MopartGasket Sealant in an aerosol can should be
applied using a thin, even coat sprayed completely
over both surfaces to be joined, and both sides of a
gasket. Then proceed with assembly. Material in a
can w/applicator can be brushed on evenly over the
sealing surfaces. Material in an aerosol can should be
used on engines with multi-layer steel gaskets.
STANDARD PROCEDURE - ENGINE GASKET
SURFACE PREPARATION
To ensure engine gasket sealing, proper surface
preparation must be performed, especially with the
use of aluminum engine components and multi-layer
steel cylinder head gaskets.
Neveruse the following to clean gasket surfaces:
²Metal scraper
²Abrasive pad or paper to clean cylinder block
and head
²High speed power tool with an abrasive pad or a
wire brush (Fig. 3)
NOTE: Multi-Layer Steel (MLS) head gaskets require
a scratch free sealing surface.
Only use the following for cleaning gasket surfaces:
²Solvent or a commercially available gasket
remover
²Plastic or wood scraper (Fig. 3)
²Drill motor with 3M RolocŸ Bristle Disc (white
or yellow) (Fig. 3)
CAUTION: Excessive pressure or high RPM (beyond
the recommended speed), can damage the sealing
surfaces. The mild (white, 120 grit) bristle disc is
recommended. If necessary, the medium (yellow, 80
grit) bristle disc may be used on cast iron surfaces
with care.
STANDARD PROCEDURE - MEASURING
BEARING CLEARANCE USING PLASTIGAGE
Engine crankshaft bearing clearances can be deter-
mined by use of Plastigage or equivalent. The follow-
ing is the recommended procedure for the use of
Plastigage:
(1) Remove oil film from surface to be checked.
Plastigage is soluble in oil.
(2) Place a piece of Plastigage across the entire
width of the bearing shell in the cap approximately
6.35 mm (1/4 in.) off center and away from the oil
holes (Fig. 4). (In addition, suspected areas can be
checked by placing the Plastigage in the suspected
area). Torque the bearing cap bolts of the bearing
being checked to the proper specifications.
(3) Remove the bearing cap and compare the
width of the flattened Plastigage with the metricscale provided on the package. Locate the band clos-
est to the same width. This band shows the amount
of clearance in thousandths of a millimeter. Differ-
ences in readings between the ends indicate the
amount of taper present. Record all readings taken.
Compare clearance measurements to specs found in
engine specifications (Refer to 9 - ENGINE - SPECI-
FICATIONS).Plastigage generally is accompa-
nied by two scales. One scale is in inches, the
other is a metric scale.
Fig. 3 Proper Tool Usage For Surface Preparation
1 - ABRASIVE PAD
2 - 3M ROLOCŸ BRISTLE DISC
3 - PLASTIC/WOOD SCRAPER
Fig. 4 Plastigage Placed in Lower ShellÐTypical
1 - PLASTIGAGE
KJENGINE9s-11
ENGINE - 2.4L (Continued)

REMOVAL
(1) Remove cylinder head cover. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL)
(2) Remove camshaft position sensor and camshaft
target magnet. (Refer to 8 - ELECTRICAL/IGNI-
TION CONTROL/CAMSHAFT POSITION SENSOR -
REMOVAL)
(3) Remove timing belt. (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - REMOVAL)(4) Remove camshaft sprockets and timing belt
rear cover. (Refer to 9 - ENGINE/VALVE TIMING/
TIMING BELT / CHAIN COVER(S) - REMOVAL)
(5) Bearing caps are identified for location.
Remove the outside bearing caps first (Fig. 17).
(6) Loosen the camshaft bearing cap attaching
fasteners in sequence shown (Fig. 18) one camshaft
at a time.
CAUTION: Camshafts are not interchangeable. The
intake cam number 6 thrust bearing face spacing is
wider.
(7) Identify the camshafts before removing from
the head. The camshafts are not interchangeable.
(8) Remove camshafts from cylinder head.
NOTE: If removing rocker arms, identify for reinstal-
lation in the original position.
CLEANING
Clean camshaft with a suitable solvent.
Fig. 15 Camshafts
CAM PLUG - NOT SHOWN
1 - CAMSHAFT BEARING CAPS
2 - PLUG
3 - CAMSHAFT
4 - CYLINDER HEAD
5 - CAMSHAFT OIL SEAL
Fig. 16 Camshaft End Play - Typical
Fig. 17 Camshaft Bearing Cap Identification
Fig. 18 Camshaft Bearing Cap - Removal
1 - REMOVE OUTSIDE BEARING CAPS FIRST
9s - 24 ENGINEKJ
CAMSHAFT(S) (Continued)

CYLINDER HEAD COVER
REMOVAL
(1) Remove intake manifold. (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL)
(2) Remove ignition coil and spark plug wires.
(3) Disconnect PCV and make-up air hoses from
cylinder head cover.
(4) Remove cylinder head cover bolts.
(5) Remove cylinder head cover from cylinder
head.
CLEANING
Clean cylinder head and cover mating surfaces
using a suitable solvent.
INSPECTION
Inspect cover rails for flatness.
INSTALLATION
NOTE: Replace spark plug well seals and bolt
assemblies when installing a new cylinder head
cover gasket.
(1) Install new cylinder head cover gaskets and
spark plug well seals (Fig. 22).
(2) Replace cylinder head cover bolt assemblies
(Fig. 23).
CAUTION: Do not allow oil or solvents to contact
the timing belt as they can deteriorate the rubber
and cause tooth skipping.(3) Apply MopartEngine RTV GEN II at the
camshaft cap corners and at the top edges of the 1/2
round seal (Fig. 24).
Fig. 22 Spark Plug Well Seals
Fig. 23 Cylinder Head Cover Bolt Assembly
Fig. 24 Sealer Locations - Typical
1 ± SEALER LOCATION
9s - 26 ENGINEKJ

(4) Install cylinder head cover assembly to cylin-
der head. Install all bolts, ensuring the two (2) bolts
containing the sealing washer are located in the cen-
ter locations of cover. Tighten bolts in sequence
shown in (Fig. 25). Using a 3 step torque method as
follows:
(a) Tighten all bolts to 4.5 N´m (40 in. lbs.).
(b) Tighten all bolts to 9.0 N´m (80 in. lbs.).
(c) Tighten all bolts to 12 N´m (105 in. lbs.).
(5) Install intake manifold.
(6) Install ignition coil and spark plug wires.
Tighten fasteners to 12 N´m (105 in. lbs.).
(7) If the PCV valve was removed, apply Mopart
Thread Sealant with Teflon to threads and install
valve to cylinder head cover. Tighten PCV valve to 8
N´m (70 in. lbs.).
(8) Connect PCV and make-up air hoses to cylin-
der head cover.
INTAKE/EXHAUST VALVES &
SEATS
DESCRIPTION
The four valves per cylinder are opened by using
roller rocker arms which pivot on hydraulic lash
adjusters. The valves have chrome plated valve
stems. Viton rubber valve stem seals are integral
with the spring seats.They have chrome plated stems
to prevent scuffing. Viton rubber valve stem seals are
integral with the spring seats. The valves, spring
retainers,and locks, are the 3 - bead lock design
CLEANING
(1) Clean all valves thoroughly and discard
burned, warped and cracked valves.
VALVE SPRINGS
REMOVAL
REMOVAL - CYLINDER HEAD ON
(1) Remove camshafts.
(2) Rotate crankshaft until piston is at TDC on
compression.
(3) With air hose attached to adapter tool installed
in spark plug hole, apply 90-120 psi air pressure.
(4) Using Special Tool MD-998772-A with adapter
6779 (Fig. 26), compress valve springs and remove
valve locks.
(5) Remove valve spring(s).
(6) Remove valve stem seal(s) by a using valve
stem seal tool (Fig. 28).
REMOVAL - CYLINDER HEAD OFF
(1) With cylinder head removed from cylinder
block, compress valve springs using a universal valve
spring compressor.
(2) Remove valve retaining locks, valve spring
retainers, valve stem seals and valve springs.
(3) Before removing valves,remove any burrs
from valve stem lock grooves to prevent dam-
age to the valve guides.Identify valves, locks and
retainers to insure installation in original location.
(4) Inspect the valves. (Refer to 9 - ENGINE/CYL-
INDER HEAD/VALVE SPRINGS - INSPECTION)
Fig. 25 CYLINDER HEAD TIGHTENING SEQUENCE
Fig. 26 Valve Spring - Removal/Installation
1 - VALVE SPRING COMPRESSOR MD 998772A
2 - AIR HOSE
KJENGINE9s-27
CYLINDER HEAD COVER (Continued)

shown in (Fig. 34). Refer to for Engine Specifications
(Refer to 9 - ENGINE - SPECIFICATIONS). Correct
piston to bore clearance must be established in order
to assure quiet and economical operation.
NOTE: Pistons and cylinder bores should be mea-
sured at normal room temperature, 21ÉC (70ÉF).
STANDARD PROCEDURE - CYLINDER BORE
HONING
(1) Used carefully, the cylinder bore resizing hone,
recommended tool C-823 or equivalent, equipped
with 220 grit stones, is the best tool for this honing
procedure. In addition to deglazing, it will reduce
taper and out-of-round as well as removing light
scuffing, scoring or scratches. Usually a few strokes
will clean up a bore and maintain the required lim-
its.
(2) Deglazing of the cylinder walls may be done
using a cylinder surfacing hone, recommended toolC-3501 or equivalent, equipped with 280 grit stones,
if the cylinder bore is straight and round. 20±60
strokes depending on the bore condition, will be suf-
ficient to provide a satisfactory surface. Use a light
honing oil.Do not use engine or transmission oil,
mineral spirits or kerosene.Inspect cylinder walls
after each 20 strokes.
(3) Honing should be done by moving the hone up
and down fast enough to get a cross-hatch pattern.
When hone marksintersectat 40-60 degrees, the
cross hatch angle is most satisfactory for proper seat-
ing of rings (Fig. 36).
(4) A controlled hone motor speed between
200±300 RPM is necessary to obtain the proper cross-
hatch angle. The number of up and down strokes per
minute can be regulated to get the desired 40±60
degree angle. Faster up and down strokes increase
the cross-hatch angle.
(5) After honing, it is necessary that the block be
cleaned again to remove all traces of abrasive.
CAUTION: Ensure all abrasives are removed from
engine parts after honing. It is recommended that a
solution of soap and hot water be used with a
brush and the parts then thoroughly dried. The bore
can be considered clean when it can be wiped
clean with a white cloth and cloth remains clean.
Oil the bores after cleaning to prevent rusting.
CLEANING
Clean cylinder block thoroughly using a suitable
cleaning solvent.
Fig. 34 Checking Cylinder Bore -Typical
Fig. 35 Piston Measurement - Typical
Fig. 36 Cylinder Bore Cross-Hatch Pattern
1 - CROSS-HATCH PATTERN
2 - 40ɱ60É
KJENGINE9s-31
ENGINE BLOCK (Continued)

OPERATION
The crankshaft transfers force generated by com-
bustion within the cylinder to the flywheel or flex-
plate.
STANDARD PROCEDURE - CRANKSHAFT END
PLAY
(1) Using Dial Indicator C-3339 and Mounting
Post L-4438, attach to front of engine, locating probe
perpendicular on nose of crankshaft (Fig. 40).
(2) Move crankshaft all the way to the rear of its
travel.
(3) Zero the dial indicator.
(4) Move crankshaft all the way to the front and
read the dial indicator. Refer to Engine Specifica-
tions.
REMOVAL
NOTE: Crankshaft can not be removed when engine
is in vehicle.
(1) Remove engine assembly from vehicle. (Refer to
9 - ENGINE - REMOVAL)
(2) Remove flex plate and crankshaft rear oil seal.
(3) Mount engine on a repair stand.
(4) Drain engine oil and remove oil filter.
(5) Remove the oil pan. (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL)
(6) Remove the timing belt covers. (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL)(7) Remove the timing belt. (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - REMOVAL)
(8) Remove the oil pump. (Refer to 9 - ENGINE/
LUBRICATION/OIL PUMP - REMOVAL)
(9) Remove balance shafts and housing assembly.
(Refer to 9 - ENGINE/VALVE TIMING/BALANCE
SHAFT - REMOVAL)
(10) Remove all bedplate bolts from the engine
block (Fig. 41).
(11) Using a mallet gently tap the bedplate loose
from the engine block dowel pins.
CAUTION: Do not pry up on one side of the bed-
plate. Damage may occur to cylinder block to bed-
plate alignment and thrust bearing.
(12) Bedplate should be removed evenly from the
cylinder block dowel pins to prevent damage to the
dowel pins and thrust bearing.
(13) Lift out crankshaft from cylinder block. Do
not damage the main bearings or journals when
removing the crankshaft.
Fig. 39 Crankshaft - Typical
1 - MAIN BEARING JOURNALS
2 - COUNTER BALANCE WEIGHTS
Fig. 40 CHECKING CRANKSHAFT END PLAY
Fig. 41 Bedplate Bolt Tightenening Sequence
KJENGINE9s-33
CRANKSHAFT (Continued)

INSTALLATION
CAUTION: If burr or scratch is present on the
crankshaft edge (chamfer), cleanup with 400 grit
sand paper to prevent seal damage during installa-
tion of new seal.
NOTE: When installing seal, no lube on seal is
needed.
(1) Place Special Tool 6926-1 Seal Guide on crank-
shaft (Fig. 57).
(2) Position seal over guide tool (Fig. 57). Guide
tool should remain on crankshaft during installation
of seal. Ensure that the lip of the seal is facing
towards the crankcase during installation.
CAUTION: If the seal is driven into the block past
flush, this may cause an oil leak.
(3) Drive the seal into the block using Special Tool
6926-2 and handle C-4171 (Fig. 58) until the tool bot-
toms out against the block (Fig. 59).
Fig. 56 Rear Crankshaft Oil SealÐRemoval
1 - REAR CRANKSHAFT SEAL
2 - ENGINE BLOCK
3 - ENGINE BLOCK
4 - REAR CRANKSHAFT SEAL METAL CASE
5 - PRY IN THIS DIRECTION
6 - CRANKSHAFT
7 - SCREWDRIVER
8 - REAR CRANKSHAFT SEAL DUST LIP
9 - SCREWDRIVER
Fig. 57 Rear Crankshaft Seal and Special Tool
6926-1
1 - SPECIAL TOOL 6926±1 PILOT
2 - SEAL
Fig. 58 Crankshaft Seal and Special Tools 6926-2 &
C-4171
1 - SPECIAL TOOL 6926±1 PILOT
2 - SEAL
3 - SPECIAL TOOL 6926±2 INSTALLER
4 - SPECIAL TOOL C-4171
KJENGINE9s-39
CRANKSHAFT OIL SEAL - REAR (Continued)

(6) Install oil pressure switch and connector. (Refer
to 9 - ENGINE/LUBRICATION/OIL PRESSURE
SENSOR/SWITCH - INSTALLATION)
OIL
STANDARD PROCEDURE
ENGINE OIL LEVEL CHECK
The best time to check engine oil level is after it
has sat overnight, or if the engine has been running,
allow the engine to be shut off for at least 5 minutes
before checking oil level.
Checking the oil while the vehicle is on level
ground will improve the accuracy of the oil level
reading. Remove dipstick and observe oil level. Add
oil only when the level is at or below the ADD mark
(Fig. 78).
STANDARD PROCEDURE - ENGINE OIL AND
FILTER CHANGE
Change engine oil at mileage and time intervals
described in the Maintenance Schedule. (Refer to
LUBRICATION & MAINTENANCE/MAINTE-
NANCE SCHEDULES - DESCRIPTION)
WARNING: NEW OR USED ENGINE OIL CAN BE
IRRITATING TO THE SKIN. AVOID PROLONGED OR
REPEATED SKIN CONTACT WITH ENGINE OIL.
CONTAMINANTS IN USED ENGINE OIL, CAUSED BY
INTERNAL COMBUSTION, CAN BE HAZARDOUS TO
YOUR HEALTH. THOROUGHLY WASH EXPOSED
SKIN WITH SOAP AND WATER. DO NOT WASH
SKIN WITH GASOLINE, DIESEL FUEL, THINNER, OR
SOLVENTS, HEALTH PROBLEMS CAN RESULT. DO
NOT POLLUTE, DISPOSE OF USED ENGINE OIL
PROPERLY. CONTACT YOUR DEALER OR GOVERN-
MENT AGENCY FOR LOCATION OF COLLECTION
CENTER IN YOUR AREA.
Run engine until achieving normal operating tem-
perature.
(1) Position the vehicle on a level surface and turn
engine off.(2) Hoist and support vehicle on safety stands.
Refer to Hoisting and Jacking Recommendations.
(Refer to LUBRICATION & MAINTENANCE/HOIST-
ING - STANDARD PROCEDURE)
(3) Remove oil fill cap.
(4) Place a suitable drain pan under crankcase
drain.
(5) Remove drain plug from crankcase and allow
oil to drain into pan. Inspect drain plug threads for
stretching or other damage. Replace drain plug and
gasket if damaged.
(6) Remove oil filter. (Refer to 9 - ENGINE/LUBRI-
CATION/OIL FILTER - REMOVAL)
(7) Install and tighten drain plug in crankcase.
(8) Install new oil filter. (Refer to 9 - ENGINE/LU-
BRICATION/OIL FILTER - INSTALLATION)
(9) Lower vehicle and fill crankcase with specified
type and amount of engine oil. (Refer to LUBRICA-
TION & MAINTENANCE/FLUID TYPES -
DESCRIPTION)
(10) Install oil fill cap.
(11) Start engine and inspect for leaks.
(12) Stop engine and inspect oil level.
NOTE: Care should be exercised when disposing
used engine oil after it has been drained from a
vehicle engine. Refer to the WARNING listed above.
OIL FILTER
DESCRIPTION
The engine oil filter is a high quality full-flow, dis-
posable type. Replace the oil filter with a Mopartor
the equivalent.
REMOVAL
(1) Raise vehicle on hoist.
(2) Position an oil collecting container under oil fil-
ter location.
CAUTION: When servicing the oil filter avoid
deforming the filter can by installing the remove/in-
stall tool band strap against the can to base lock
seam. The lock seam joining the can to the base is
reinforced by the base plate.
(3) Using a suitable filter wrench, turn oil filter
counterclockwise to remove (Fig. 79).
INSTALLATION
(1) Clean and check filter mounting surface. The
surface must be smooth, flat and free of debris or
pieces of gasket.
(2) Lubricate new oil filter gasket with clean
engine oil.
Fig. 78 Oil Level
1 - ENGINE OIL LEVEL DIPSTICK
KJENGINE9s-47
LUBRICATION (Continued)