²Third All to 68 N´m (50 ft. lbs.)
CAUTION: Do not use a torque wrench for the fol-
lowing step.
²Fourth Turn an additional 1/4 Turn,
(5) Install rocker arms. (Refer to 9 - ENGINE/
CYLINDER HEAD/ROCKER ARMS - INSTALLA-
TION)
(6) Install camshafts. (Refer to 9 - ENGINE/CYL-
INDER HEAD/CAMSHAFT(S) - INSTALLATION).
(7) Install cylinder head cover. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION)
(8) Install timing belt rear cover and timing belt
idler pulley. (Refer to 9 - ENGINE/VALVE TIMING/
TIMING BELT / CHAIN COVER(S) - INSTALLA-
TION)
(9) Install timing belt and camshaft sprockets.
(Refer to 9 - ENGINE/VALVE TIMING/TIMING
BELT/CHAIN AND SPROCKETS - INSTALLATION)
(10) Connect cam sensor and fuel injectors wiring
connectors.(11) Install ignition coil and wires. Connect igni-
tion coil wiring connector.
(12) Install accessary drive bracket.
(13) Install power steering pump to cylinder head.
(14) Raise vehicle and install the exhaust pipe to
the manifold.
(15) Install accessory drive belts. (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION)
(16) Install heater tube support bracket to cylinder
head.
(17) Install intake manifold.
(18) Connect all vacuum lines, electrical wiring,
ground straps and fuel line.
(19) Fill cooling system. (Refer to 7 - COOLING -
STANDARD PROCEDURE)
(20) Connect battery negative cable.
CAMSHAFT OIL SEAL(S)
REMOVAL
(1) Remove timing belt. (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - REMOVAL)
(2) Hold each camshaft sprocket with Special Tool
6847 while removing center bolt (Fig. 12).
(3) Remove camshaft sprockets.
(4) Remove exhaust camshaft target ring.
(5) Remove exhaust camshaft sensor.
CAUTION: Inspect sensor and target ring for exces-
sive wear. Clean sensor face and install new spacer
pad.
(6) Remove rear timing belt cover. (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL)
(7) Remove camshaft seal using Special Tool
C-4679-A (Fig. 13).
CAUTION: Do not nick shaft seal surface or seal
bore.
INSTALLATION
NOTE: Clean and inspect sensor and target ring for
excessive wear. Clean sensor face and always
install a new spacer pad.
(1) Shaft seal surface must be free of varnish, dirt
or nicks. Polish with 400 grit paper if necessary.
(2) Install camshaft seals into cylinder head using
Special Tool MD-998306 until flush with head (Fig.
14).
Fig. 10 Cylinder Head Gasket Positioning
1 - PART NUMBER FACES UP
2 - NO. 1 CYLINDER
Fig. 11 Cylinder Head Tightening Sequence
9s - 22 ENGINEKJ
CYLINDER HEAD (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)
(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)
INSPECTION
(1) Whenever valves have been removed for inspec-
tion, reconditioning or replacement, valve springs
should be tested for correct tension. Discard the
springs that do not meet specifications. The following
specifications apply to both intake and exhaust
valves springs:
²Valve Closed Nominal TensionÐ76 lbs. @ 38.0
mm (1.50 in.)
²Valve Open Nominal TensionÐ136 lbs. @ 29.75
mm (1.17 in.)
(2) Inspect each valve spring for squareness with a
steel square and surface plate, test springs from both
ends. If the spring is more than 1.5 mm (1/16 inch)
out of square, install a new spring.
INSTALLATION
INSTALLATION - CYLINDER HEAD ON
(1) Install valve seal/valve spring seat assembly
(Fig. 27). Push the assembly down to seat it onto the
valve guide.
(2) Install valve spring and retainer, use Special
Tool MD-998772-A with adapter 6779 to compress
valve springs only enough to install locks. Correct
alignment of tool is necessary to avoid nicking valve
stems.
(3) Remove air hose and install spark plugs.
(4) Install camshafts and cylinder head cover .
INSTALLATION - CYLINDER HEAD OFF
(1) Coat valve stems with clean engine oil and
insert in cylinder head.(2) Install new valve stem seals on all valves
using a valve stem seal tool (Fig. 28). The valve stem
seals should be pushed firmly and squarely over
valve guide.
CAUTION: When oversize valves are used, the cor-
responding oversize valve seal must also be used.
Excessive guide wear may result if oversize seals
are not used with oversize valves.
(3) Install valve springs and retainers. Compress
valve springs only enough to install locks, taking
care not to misalign the direction of compression.
Nicked valve stems may result from misalignment of
the valve spring compressor.
CAUTION: When depressing the valve spring retain-
ers with valve spring compressor the locks can
become dislocated. Ensure both locks are in the
correct location after removing tool.
(4) Check the valve spring installed height B after
refacing the valve and seat (Fig. 29). Make sure mea-
surements are taken from top of spring seat to the
bottom surface of spring retainer. If height is greater
than 38.75 mm (1.525 in.), install a 0.762 mm (0.030
in.) spacer under the valve spring seat to bring
spring height back within specification.
HYDRAULIC LIFTERS
DIAGNOSIS AND TESTING - LASH ADJUSTER
(TAPPET) NOISE DIAGNOSIS
A tappet-like noise may be produced from several
items. Check the following items.
(1) Engine oil level too high or too low. This may
cause aerated oil to enter the adjusters and cause
them to be spongy.
Fig. 27 Valve Stem Seal/Valve Spring Seat - Typical
1 - 3-GROOVE -VALVE RETAINING LOCKS
2 - VALVE SPRING
3 - VALVE SEAL AND VALVE SPRING SEAT ASSEMBLY
4 - VALVE SPRING RETAINER
Fig. 28 Valve Stem Oil Seal Tool
1 - VALVE SEAL TOOL
2 - VALVE STEM
9s - 28 ENGINEKJ
VALVE SPRINGS (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)
(4) Install flex plate. Apply MopartLock & Seal
Adhesive to bolt threads and tighten bolts to 95 N´m
(70 ft. lbs.).
(5) Install the transmission.
PISTON & CONNECTING ROD
DESCRIPTION
The pistons are made of a cast aluminum alloy.
The pistons have pressed-in pins attached to forged
powdered metal connecting rods. The pistons pin is
offset 1 mm (0.0394 in.) towards the thrust side of
the piston. The connecting rods are a cracked cap
design and are not repairable. Hex head cap screws
are used to provide alignment and durability in the
assembly. The pistons and connecting rods are ser-
viced as an assembly.
OPERATION
The piston and connecting rod is the link between
the combustion force to the crankshaft.
REMOVAL
NOTE: Cylinder Head must be removed before Pis-
tons and Rods. Refer to Cylinder Head Removal in
this section.
(1) Remove top ridge of cylinder bores with a reli-
able ridge reamer before removing pistons from cyl-
inder block.Be sure to keep tops of pistons
covered during this operation. Mark piston with
matching cylinder number (Fig. 60).
(2) Remove oil pan. Scribe the cylinder number on
the side of the rod and cap (Fig. 61) for identification.
(3) Pistons have a directional stamping in the
front half of the piston facing towards thefrontof
engine.
(4) Pistons and connecting rods must be removed
from top of cylinder block. Rotate crankshaft so that
each connecting rod is centered in cylinder bore.
(5) Remove Balance Shaft Assembly. Refer to Bal-
ance Shaft Removal in this section.
(6) Remove connecting rod cap bolts. Push each
piston and rod assembly out of cylinder bore.
NOTE: Be careful not to nick crankshaft journals.
(7) After removal, install bearing cap on the mat-
ing rod.
(8) Piston and Rods are serviced as an assembly.
Fig. 59 Rear Crankshaft SealÐInstallation
1 - SPECIAL TOOL 6926±2 INSTALLER
Fig. 60 Piston Markings
1 - DIRECTIONAL ARROW WILL BE IMPRINTED IN THIS AREA
9s - 40 ENGINEKJ
CRANKSHAFT OIL SEAL - REAR (Continued)
EXHAUST MANIFOLD
DESCRIPTION
The exhaust manifold is made of Hi-Silicone Moly
nodular cast iron for strength and high tempera-
tures. The manifold attaches to the cylinder head.
OPERATION
The exhaust manifold collects the exhaust gasses
exiting the combustion chambers. Then it channels
the exhaust gasses to the exhaust pipe attached to
the manifold.
REMOVAL
(1) Raise vehicle and disconnect exhaust pipe from
the exhaust manifold.
(2) Lower the vehicle.
(3) Disconnect upstream oxygen sensor connector
at the rear of exhaust manifold.
(4) Remove the air cleaner bracket (Fig. 91).
(5) Remove the heat shield.
(6) Remove the bolts attaching the manifold to the
cylinder head.
(7) Remove exhaust manifold.
(8) Inspect the manifold. (Refer to 9 - ENGINE/
MANIFOLDS/EXHAUST MANIFOLD - INSPEC-
TION)
CLEANING
(1) Discard gasket (if equipped) and clean all sur-
faces of manifold and cylinder head.
INSPECTION
(1) Inspect manifold gasket surfaces for flatness
with straight edge. Surface must be flat within 0.15
mm per 300 mm (0.006 in. per foot) of manifold
length.
(2) Inspect manifolds for cracks or distortion.
Replace manifold as necessary.
INSTALLATION
(1) Clean the manifold mating surfaces.
(2) Install exhaust manifold with a new gasket.
Tighten attaching nuts to 20 N´m (175 in. lbs.).
(3) Attach exhaust pipe to exhaust manifold and
tighten fasteners to 37 N´m (27 ft. lbs.).
(4) Install and connect the oxygen sensor. (Refer to
14 - FUEL SYSTEM/FUEL INJECTION/O2 SENSOR
- COMPONENT LOCATION)
(5) Install the heat shield.
(6) Install the air cleaner bracket.
TIMING BELT COVER(S)
REMOVAL
FRONT COVER
(1) Remove crankshaft vibration damper. (Refer to
9 - ENGINE/ENGINE BLOCK/VIBRATION
DAMPER - REMOVAL)
(2) Remove generator drive belt tensioner assem-
bly. (Refer to 7 - COOLING/ACCESSORY DRIVE/
BELT TENSIONERS - REMOVAL)
(3) Remove timing belt front cover bolts, and
remove covers.
REAR COVER
(1) Remove front covers.
(2) Remove timing belt. (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - REMOVAL)
(3) Hold camshaft sprocket with Special Tool 6847
while removing center bolt.
(4) Remove timing belt idler pulley.
(5) Remove rear cover fasteners and remove cover
from engine.
INSTALLATION
REAR COVER
(1) Install timing belt rear cover and bolts (Fig.
92). Torque bolts to 12 N´m (105 in. lbs).
Fig. 91 AIR CLEANER BRACKET
1 - AIR CLEANER BRACKET
2 - BOLT (2)
KJENGINE9s-53