(3) Slowly rotate crankshaft clockwise, forcing out
upper half of bearing shell.
INSTALLATION
NOTE: Only one main bearing should be selec-
tively fitted while all other main bearing caps are
properly tightened.
When installing a new upper bearing shell, slightly
chamfer the sharp edges from the plain side.
(1) Start bearing in place, and insert Main Bearing
Tool C-3059 into oil hole of crankshaft (Fig. 64).
(2) Slowly rotate crankshaft counterclockwise slid-
ing the bearing into position. Remove Special Main
Bearing Tool C-3059.
(3) Install each main cap and tighten bolts finger
tight.
(4) Tighten number 1, 3 and 4 main cap bolts to 41
N´m + 1/4 Turn (30 ft. lbs.+ 1/4 Turn).(5) Rotate the crankshaft until number 6 piston is
at TDC.
(6) To ensure correct thrust bearing alignment the
following procedure must be done:
a. Move crankshaft all the way to the rear of its
travel.
b. Then, move crankshaft all the way to the front
of its travel.
c. Wedge a appropriate tool between the rear of
the cylinder block and rear crankshaft counter-
weight. This will hold the crankshaft in it's most for-
ward position.
d. Tighten the #2 Thrust Bearing cap bolts to 41
N´m + 1/4 Turn (30 ft. lbs.+ 1/4 Turn). Remove the
holding tool.
(7) Install oil pan.
(8) Fill engine crankcase with proper oil to correct
level.
CRANKSHAFT OIL SEALÐFRONT
REMOVAL
(1) Disconnect negative cable from battery.
(2) Raise vehicle on hoist. Remove right wheel and
inner splash shield.
(3) Remove drive belt. Refer to Group 7, Cooling
System for procedure.
(4) Remove crankshaft damper (Fig. 65).
(5) Using Tool 6341A to remove oil seal (Fig. 66).
Be careful not to damage that crankshaft seal sur-
face of cover.
INSTALLATION
(1) Install new seal by using Tool C-4992 (Fig. 67).
(2) Place seal into opening with seal spring
towards the inside of engine. Install seal until flush
with cover.
(3) Install crankshaft pulley using plate L-4524.
Thrust Bearing/washer and 5.9 inch screw (Fig. 68).
Fig. 63 Main Bearing Identification
Fig. 64 Removing and Installing Upper Main Bearing
With Special Tool C-3059
Fig. 65 Crankshaft DamperÐRemoval
NS3.3/3.8L ENGINE 9 - 117
REMOVAL AND INSTALLATION (Continued)
(4) Install drive belt Refer to Group 7, Cooling
System for installation procedure.
(5) Install inner splash shield and wheel.
(6) Lower vehicle and connect negative cable to
battery.
CRANKSHAFT OIL SEALÐREAR
REMOVAL
(1) Insert a 3/16 flat bladed pry tool between the
dust lip and the metal case of the crankshaft seal.
Angle the pry tool (Fig. 69) through the dust lip
against metal case of the seal. Pry out seal.
CAUTION: Do not permit the pry tool blade to con-
tact crankshaft seal surface. Contact of the pry toolblade against crankshaft edge (chamfer) is permit-
ted.
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.
(1) Place Special Tool 6926-1 magnetic pilot tool on
crankshaft (Fig. 70).
(2) Lightly coat seal O.D. with MopartStud N'
Bearing Mount Adhesive or equivalent.
(3) Place seal over Special Tool 6926-1 Pilot. Using
Special Tool 6926-2 Installer with C-4171 Handle,
drive seal into the retainer housing (Fig. 70).
REAR CRANKSHAFT SEAL RETAINER
When retainer removal is required, remove
retainer and clean engine block and retainer of old
gasket. Make sure surfaces are clean and free of oil.
Fig. 66 Front Crankshaft Oil SealÐRemoval
Fig. 67 Crankshaft Oil SealÐInstallation
Fig. 68 Crankshaft DamperÐInstallation
Fig. 69 Rear Crankshaft Oil SealÐRemoval
9 - 118 3.3/3.8L ENGINENS
REMOVAL AND INSTALLATION (Continued)
Install new gasket and tighten screws to 12 N´m (105
in. lbs.).
OIL FILTER
CAUTION: When servicing the oil filter (Fig. 71)
avoid deforming the filter can by installing the
remove/install 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.
(1) Using Tool C-4065, turn filter counterclockwise
to remove from base. Properly discard filter.
(2) Wipe base clean, then inspect gasket contact
surface.
(3) Lubricate gasket of new filter with clean
engine oil.
(4) Install new filter until gasket contacts base.
Tighten filter 1 turn or 20 N´m (15 ft. lbs.). Use filter
wrench if necessary.
(5) Start engine and check for leaks.
ENGINE OIL GALLERY PLUGS
REMOVAL
Using a blunt tool such as a drift and a hammer,
strike the bottom edge of the cup plug. With the cup
plug rotated, grasp firmly with pliers or other suit-
able tool and remove plug (Fig. 72).CAUTION: Do not drive cup plug into the casting
as restricted cooling can result and cause serious
engine problems.
INSTALLATION
Thoroughly clean inside of cup plug hole in cylin-
der block or head. Be sure to remove old sealer.
Lightly coat inside of cup plug hole with Loctite Stud
N' Bearing Mount or equivalent. Make certain the
new plug is cleaned of all oil or grease. Using proper
drive plug, drive plug into hole so that the sharp
edge of the plug is at least 0.5 mm (0.020 in.) inside
the lead-in chamfer.
DISASSEMBLY AND ASSEMBLY
OIL PUMP
It is necessary to remove the oil pan, oil pickup
and chain case cover to service the oil pump rotors.
The oil pump pressure relief valve can be serviced by
removing the oil pan and oil pickup tube. Refer to
Timing Chain Cover Removal and Installation of this
section for procedures.
DISASSEMBLY
(1) To remove the relief valve, proceed as follows:
Fig. 70 Rear Crankshaft Oil SealÐInstallation
Fig. 71 Oil Filter
Fig. 72 Core Hole Plug Removal
NS3.3/3.8L ENGINE 9 - 119
REMOVAL AND INSTALLATION (Continued)
SPLASH LUBRICATION
Oil returning to the pan from pressurized compo-
nents supplies lubrication to the valve stems. Cylin-
der bores and wrist pins are splash lubricated from
directed slots on the connecting rod thrust collars.
ENGINE COMPONENTS
CYLINDER BLOCK AND BEDPLATE ASSEM-
B LY:A partial open deck is used for cooling and
weight reduction with water pump molded into the
block. Nominal wall thickness is 4 mm. The bedplate
incorporates main bearing caps. Rear seal retainer is
integral with the block.
CRANKSHAFT:A nodular cast iron crankshaft is
used. The engine has 5 main bearings, with number
3 flanged to control thrust. The 52 mm diameter
main and 48 mm diameter crank pin journals (all)
have undercut fillet radiuses that are deep rolled for
added strength. To optimize bearing loading 8 coun-
terweights are used. Hydrodynamic seals provide end
sealing, where the crankshaft exits the block.
Anaerobic gasket material is used for parting line
sealing. A sintered iron timing belt sprocket is
mounted on the crankshaft nose. This sprocket trans-
mits crankshaft movement, via timing belt to the
camshaft sprocket providing timed valve actuation.
PISTONS:The SOHC EngineDOES NOThave
provision for a free wheeling valve train. Non free
wheeling valve train means, in the event of a broken
timing belt Pistons will contact the Valves. All
engines use pressed-in piston pins to attach forged
powdered metal connecting rods. The connecting rods
are a cracked cap design and are not repairable. Hexhead cap screw are used to provide alignment and
durability in the assembly. Pistons And Connecting
rods are serviced as an assembly.
PISTON RINGS:The piston rings include a
molybdenum faced top ring for reliable compression
sealing and a taper faced intermediate ring for addi-
tional cylinder pressure control. Oil Control Ring
Package consist of 2 steel rails and a expander
spacer.
CYLINDER HEADÐSOHC:It features a Single
Over Head Camshaft, four-valves per cylinder cross
flow design. The valves are arranged in two inline
banks, with the two intake per cylinder facing
toward the radiator. The exhaust valves facing
toward the dash panel. Rocker arm shafts mount
directly to the cylinder head. It incorporates powder
metal valve guides and seats. The hollow rocker arm
shafts supplies oil to the hydraulic lash adjusters,
camshaft and valve mechanisms.
CAMSHAFTÐSOHC:The nodular iron camshaft
has five bearing journals and 3 cam lobes per cylin-
der. Provision for cam position sensor on the cam at
the rear of cylinder head which also acts as thrust
plate. A hydrodynamic oil seal is used for oil control
at the front of the camshaft.
VALVESÐSOHC:Four valves per cylinder are
actuated by roller rocker arms/hydraulic lash adjust-
ers assemblies which pivot on rocker arm shafts. All
valves have 6 mm diameter chrome plated valve
stems. The valve train has 33 mm (1.299 inch) diam-
eter intake valves and 28 mm (1.10 inch) diameter
exhaust valves. Viton rubber valve stem seals are
integral with spring seats. Valve springs, spring
retainers, and locks are conventional design.
INTAKE MANIFOLD:The intake manifold is a
molded plastic composition, attached to the cylinder
head with ten fasteners. This long branch design
enhances low and mid-range torque.
EXHAUST MANIFOLD:The exhaust manifold is
made of nodular cast iron for strength and high tem-
peratures. Exhaust gasses exit through a machined,
articulated joint connection to the exhaust pipe.
DIAGNOSIS AND TESTING
CHECKING ENGINE OIL PRESSURE
(1) Remove oil pressure switch and install gauge
assembly C-3292 with adaptor.
(2) Run engine until thermostat opens.
CAUTION: If oil pressure is 0 at idle, Do Not per-
form the 3000 RPM test in the next step.
(3) Oil Pressure:Curb Idle25 kPa (4 psi) mini-
mum3000 RPM170-550 kPa (25-80 psi).
Fig. 2 Engine Lubrication SystemÐ SOHC
NS/GSENGINE 9 - 3
DESCRIPTION AND OPERATION (Continued)
HYDRAULIC LASH ADJUSTER NOISE
A tappet-like noise may be produced from several
items. Refer to Lash Adjuster Noise - Diagnosis in
Standard Service Procedures, outlined in this Group.
Lash adjusters are replaced with the rocker
arm as an assembly.
VALVE SEALS AND SPRINGS IN VEHICLE
REMOVAL
(1) Remove rocker arm shafts assemblies as previ-
ously outlined in this section.
(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-998772A with adapter
6779 (Fig. 19) compress valve springs and remove
valve locks.
(5) Remove valve spring.
(6) Remove valve stem seal by using a valve stem
seal tool (Fig. 20).
INSTALLATION
(1) Install valve seal/valve spring seat assembly
as outlined in the Valve Installation procedure in this
section.
(2) Using Special Tool MD-998772A compress valve
springs only enough to install locks. Correct align-
ment of tool is necessary to avoid nicking valve stems
(air pressure required), piston at TDC.
(3) Install rocker arm shaft assemblies as previ-
ously outlined in this section.
(4) Install valve cover as previously outlined in
this section.
CYLINDER HEAD
REMOVAL
(1) Perform fuel system pressure release procedure
before attempting any repairs.Refer to Group 14,
Fuel System
(2) Disconnect negative battery cable. Drain cool-
ing system. Refer to Group 7, Cooling System.
(3) Disconnect all vacuum lines, electrical wiring
and fuel lines from throttle body.
(4) Remove throttle linkage.
(5) Remove accessory drive belts. Refer to Group 7,
Cooling System for procedure.
(6) Remove power brake vacuum hose from intake
manifold.
(7) Raise vehicle and remove exhaust pipe from
manifold.
(8) Remove power steering pump assembly and set
aside.
(9) Disconnect coil pack wiring connector and
remove coil pack and bracket from engine.
(10) Remove cylinder head cover.
(11) Remove cam sensor and fuel injectors wiring
connectors.
(12) Remove intake manifold. Removal procedure
outline in Group 11.
Fig. 19 Removing and Installing Valve Spring
Fig. 20 Valve Stem Oil Seal Tool
Fig. 21 Valve Spring Assembly
9 - 10 ENGINENS/GS
REMOVAL AND INSTALLATION (Continued)
(13) Remove timing belt and camshaft sprocket.
Refer to procedure outlined in this section.
(14) Remove rocker arm shaft assemblies.
(15) Remove cylinder head bolts.
NOTE: Inspect camshaft bearing journals for scor-
ing. Cylinder head must be flat within 0.1 mm (0.004
inch) (Fig. 22).INSTALLATION
(1) Before installing the bolts the threads should
be oiled with engine oil. The 4 short bolts 110 mm
(4.330 in.) are to be installed in positions 7, 8, 9, and
10 (Fig. 23).
(2) Tighten the cylinder head bolts in the sequence
shown in (Fig. 23). Using the 4 step torque method,
tighten according to the following values:
²First All to 34 N´m (25 ft. lbs.)
²Second All to 68 N´m (50 ft. lbs.)
²Third All to 68 N´m (50 ft. lbs.)
²Fourth Turn an additional 1/4 Turn,Do not use
a torque wrench for this step.
For the rest of installation, reverse removal proce-
dure.
TIMING BELT COVER
REMOVAL
(1) Remove accessory drive belts. Refer to Group 7,
Cooling System for procedure outlined in that sec-
tion.
(2) Remove crankshaft vibration damper. Refer to
procedure outlined in this section for removal.
(3) Remove front timing belt cover (Fig. 24).
Cylinder Head and Valve Assembly
Fig. 22 Checking Cylinder Head Flatness
NS/GSENGINE 9 - 11
REMOVAL AND INSTALLATION (Continued)
INSTALLATION
(1) Install front timing cover.
(2) Install crankshaft vibration damper Refer to
procedure outlined in this section for installation.
(3) Install accessory drive belts. Refer to Group 7,
Cooling System Accessory Drive section for proce-
dure.
CAMSHAFT OIL SEAL
REMOVAL
CAUTION: Do Not Rotate the camshaft or crank-
shaft when timing belt is removed damage to the
engine may occur.(1) Remove timing belt cover and belt. Removal
procedure is outlined in this section. Remove cam-
shaft sprocket bolt, with the Modified Special Tool
C-4687-1 as shown in (Fig. 25).
(2) Hold camshaft sprocket with modified tool
while removing bolt. Remove sprocket from camshaft.
(3) Remove camshaft seal using Special Tool
C-4679±A (Fig. 26).
CAUTION: Do not nick shaft seal surface or seal
bore.
(4) Shaft seal lip surface must be free of varnish,
dirt or nicks. Polish with 400 grit paper if necessary.
Fig. 23 Cylinder Head Tightening Sequence
Fig. 24 Timing Belt Cover
Fig. 25 Modification to Special Tool
Fig. 26 Removing Camshaft Oil Seal
9 - 12 ENGINENS/GS
REMOVAL AND INSTALLATION (Continued)
INSTALLATION
(1) Install camshaft seal flush with cylinder head
using Special Tool MD 998306 (Fig. 27).
(2) Install camshaft sprocket retaining bolt. Hold
camshaft sprocket with Special Tool C-4687-1 (Fig.
25) and tighten bolt to 115 N´m (85 ft. lbs.).
TIMING BELT SYSTEM
CHECKING BELT TIMINGÐCOVER INSTALLED
²Remove number one spark plug.
²Using a dial indicator, set number one cylinder
to TDC on the compression stroke.²Remove the access plug from the outer timing
belt cover (Fig. 28).
²Check the timing mark on the camshaft
sprocket, it should align with the arrow on the rear
belt cover (Fig. 29).
REMOVALÐTIMING BELT
(1) Remove accessory drive belts. Refer to Group 7,
Cooling System for procedure outlined in that sec-
tion.
(2) Remove crankshaft damper bolt. Remove
damper using the large side of Special Tool 1026 and
insert 6827-A (Fig. 30).
Fig. 27 Installing Camshaft Seal
Fig. 28 Timing Belt System
Fig. 29 Camshaft Timing Marks
NS/GSENGINE 9 - 13
REMOVAL AND INSTALLATION (Continued)