
dure of 0.15 mm (0.005 in.), 0.40 mm (0.015 in.)
and 0.80 mm (0.030 in.) so the valve guides may
be reamed true in relation to the valve seat.
After reaming guides, the seat runout should be
measured and resurfaced if necessary. See
Refacing Valves and Valve Seats.VALVE GUIDES
NOTE: Replace cylinder head if guide does not
clean up with 0.80 mm (0.030 in.) oversize reamer,
or if guide is loose in cylinder head.
REFACING VALVES AND VALVE SEATS
The intake and exhaust valves have a 44-1/2 to 45
degree face angle. The valve seats have a 45 to 45-1/2
degree face angle. The valve face and valve seat
angles are shown in (Fig. 19).
VALVES
(1) Inspect the remaining margin after the valves
are refaced Refer to Valve Dimension Chart.
VALVE SEATS
CAUTION: Remove metal from valve seat only. Do
not remove metal from cylinder head (Fig. 20).
(1) When refacing valve seats, it is important that
the correct size valve guide pilot be used for reseat-
ing stones. A true and complete surface must be
obtained.
(2) Measure the concentricity of valve seat using
dial indicator. Total runout should not exceed 0.051
mm (0.002 in.) total indicator reading.
(3) Inspect the valve seat using Prussian blue to
determine where the valve contacts the seat. To do
this, coat valve seatLIGHTLYwith Prussian blue
then set valve in place. Rotate the valve with light
pressure. If the blue is transferred to the center of
valve face, contact is satisfactory. If the blue is trans-
ferred to top edge of valve face, lower valve seat with
a 15 degree stone. If the blue is transferred to the
bottom edge of valve face raise valve seat with a 65
degrees stone.
Fig. 18 Intake and Exhaust Valves
VALVE GUIDE SPECIFICATION CHART
Intake Valve Exhaust Valve
Dial Indicator
Reading
(Maximum):0.247 mm
(0.009 in.)0.414 mm
(0.016 in.)
Valve Guide
Reamer
OversizeValve Guide Size
0.15 mm
(0.005 in.)8.125 - 8.150 mm
(0.3198 - 0.3208 in.)
0.40 mm
(0.015 in.)8.375 - 8.400 mm
(0.3297 - 0.3307 in.)
0.80 mm
(0.030 in.)8.775 - 8.800 mm
(0.3454 - 0.3464 in.)
VALVE SPECIFICATION CHART
Intake Valve (Minimum)
Stem Diameter: 7.935 mm (0.3124 in.)
Face Angle: 44.5É
Valve Margin: 0.794 mm (0.031 in.)
Head Diameter: 45.5 mm (1.79 in.)
Length: 127.2 mm (5.008 in.)
Exhaust Valve (Minimum)
Stem Diameter: 7.906 mm (0.3112 in.)
Face Angle: 44.5É
Valve Margin: 1.191 mm (0.0469 in.)
Head Diameter: 37.5 mm (1.476 in.)
Length: 127.82 (5.032 in.)
Fig. 19 Valve Seats
NS3.3/3.8L ENGINE 9 - 101
SERVICE PROCEDURES (Continued)

(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)

(2) Drill a 3.175 mm (1/8 inch) hole into the relief
valve retainer cap and insert a self-threading sheet
metal screw into cap.
(3) Clamp screw into a vise and while supporting
chain case cover, remove cap by tapping chain case
cover using a soft hammer. Discard retainer cap and
remove spring and relief valve (Fig. 73).
(4) Remove oil pump cover screws, and lift off
cover.
(5) Remove pump rotors.
(6) Wash all parts in a suitable solvent and inspect
carefully for damage or wear (Fig. 76).
OIL PUMP ASSEMBLY
(1) Assemble pump, using new parts as required.
Install the inner rotor with chamfer facing the
cast iron oil pump cover.
(2) Tighten cover screws to 12 N´m (105 in. lbs.).
(3) Prime oil pump before installation by filling
rotor cavity with engine oil.
(4) Install chain case cover. Refer to Timing Chain
Cover Installation of this section.
HYDRAULIC TAPPETS
DISASSEMBLY
(1) Pry out plunger retainer spring clip (Fig. 74).
(2) Clean varnish deposits from inside of tappet
body above plunger cap.
(3) Invert tappet body and remove plunger cap,
plunger, flat or ball check valve, check valve spring,
check valve retainer and plunger spring. Check valve
could be flat or ball.
ASSEMBLY
(1) Clean all tappet parts in a solvent that will
remove all varnish and carbon.
(2) Replace tappets that are unfit for further ser-
vice with new assemblies.(3) If plunger shows signs of scoring or wear, valve
is pitted, or valve seat on end of plunger indicates
any condition that would prevent valve from seating,
install a new tappet assembly.
(4) Assemble tappets (Fig. 74).
CLEANING AND INSPECTION
CYLINDER HEAD
(1) Before cleaning, check for leaks, damage and
cracks.
(2) Clean cylinder head and oil passages.
(3) Check cylinder head for flatness (Fig. 75).
(4) Inspect all surfaces with a straightedge if there
is any reason to suspect leakage. If out of flatness
exceeds 0.019 mm (0.00075 in.) times the span length
in inches, in any direction, either replace head or
lightly machine the head surface. As an example, if a
12 inch span is 0.1 mm (.004 in.) out of flat, allow-
able is 12 x .019 mm (.00075 in.) equals .22 mm (.009
in.) This amount of out of flat is acceptable. Maxi-
mum of 0.2 mm (.008 in.) for grinding is permitted.
CAUTION: This is a combined total dimension of
stock removal from cylinder head and block top
surface.
Fig. 73 Oil Pressure Relief Valve
Fig. 74 Hydraulic Roller Tappet Assembly
Fig. 75 Check Cylinder Head
9 - 120 3.3/3.8L ENGINENS
DISASSEMBLY AND ASSEMBLY (Continued)

SPARK PLUG TUBE
(1) Remove valve cover. Refer to procedure out-
lined in this section.
(2) Using locking pliers remove the tube from the
cylinder head (Fig. 11). Discard old tube.
(3) Clean area around spark plug with Mopart
parts cleaner or equivalent.
(4) Apply MopartStud and Bearing Mount or
equivalent to a new tube approximately 1 mm from
theendina3mmwide area.
(5) Install sealer end of tube into the cylinder
head. Then carefully install the tube using a hard-
wood block and mallet until the tube is seated into
the bottom of the bore.
(6) Install valve cover. Refer to procedure outlined
in this section.
SPARK PLUG TUBE SEALS
The spark plug tube seals are located in the cylin-
der head cover (Fig. 12). These seals are pressed into
the cylinder head cover to seal the outside perimeterof the spark plug tubes. If these seals show signs of
hardness and/or cracking they should be replaced.
CAMSHAFT
NOTE: TO REMOVE CAMSHAFT THE CYLINDER
HEAD MUST BE REMOVED.
REMOVAL
(1) Perform fuel system pressure release procedure
before attempting any repairs.Refer to Group 14,
Fuel System
(2) Remove the cylinder head cover. Refer to proce-
dure outlined in this section.
(3) Mark rocker arm shaft assemblies so that they
are installed in their original positions.
(4) Remove rocker arm shaft bolts. Refer to proce-
dure outlined in this section.
(5) Remove timing belt, timing belt tensioner, and
camshaft sprocket. Refer to timing belt service out-
lined in this section.
(6) Remove inner timing belt cover.
(7) Remove cylinder head. Refer to procedure out-
lined in this section.
(8) Remove camshaft sensor and camshaft target
magnet.
(9) Remove camshaft from the rear of cylinder
head.
INSPECT CYLINDER HEAD FOR THE FOLLOWING:
NOTE:
²Check oil feed holes for blockage.
²Inspect cylinder head camshaft bearings for
wear, Refer to Cylinder Head, Inspection and Clean-
ing.
²Check camshaft bearing journals for scratches
and worn areas. If light scratches are present, they
may be removed with 400 grit sand paper. If deep
Fig. 10 Ingition Coil Pack
Fig. 11 Servicing Spark Plug Tubes
Fig. 12 Spark Plug Tube Seals
NS/GSENGINE 9 - 7
REMOVAL AND INSTALLATION (Continued)

(14) Install crankshaft damper using M12-1.75 x
150 mm bolt, washer, thrust bearing and nut from
Special Tool 6792. Install crankshaft damper bolt and
tighten to 142 N´m (105 ft. lbs.) (Fig. 39).
(15) Install accessory drive belts. Refer to Group 7,
Cooling System Accessory Drive section for proce-
dure.
(16) Perform camshaft and crankshaft timing
relearn. Refer to Group 25, Emission Control Sys-
tems for procedure.
TIMING BELTÐw/AUTO TENSIONERÐIF
EQUIPPED
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) Raise vehicle on a hoist and remove right inner
splash shield (Fig. 42).
(3) Remove crankshaft damper bolt. Remove
damper using the large side of Special Tool 1026 and
insert 6827-A (Fig. 30).
(4) Lower vehicle and place a jack under engine.
(5) Remove right engine mount. Refer to procedure
outlined in this section.
(6) Remove right engine mount bracket (Fig. 44).
(7) Remove front timing belt cover (Fig. 31).CAUTION: Align camshaft and crankshaft timing
marks before removing the timing belt by rotating
the engine with the crankshaft.
(8) Inserta8mmAllen wrench into the belt ten-
sioner. Before rotating the tensioner insert the long
end of a 1/8º or 3 mm Allen wrench into the pin hole
on the front of the tensioner (Fig. 33). Rotate the ten-
sioner counterclockwise with the Allen wrench, while
pushing in lightly on the 1/8 in. or 3 mm Allen
wrench, until it slides into the locking hole.
(9) Remove timing belt.
CAUTION: Do not rotate the camshafts once the
timing belt has been removed or damage to valve
components may occur.
CAMSHAFT AND CRANKSHAFT TIMING PROCEDURE AND
BELT INSTALLATION ÐSOHC ENGINE
(1) Set crankshaft sprocket to TDC by aligning the
sprocket with the arrow on the oil pump housing,
then back off to 3 notches before TDC (Fig. 35).
(2) Set camshaft to TDC by aligning mark on
sprocket with the arrow on the rear of timing belt
cover (Fig. 36).
(3) Move crankshaft to 1/2 mark before TDC (Fig.
37) for belt installation.
(4) Install timing belt. Starting at the crankshaft,
go around the water pump sprocket and then around
the camshaft sprocket.
(5) Move crankshaft sprocket to TDC to take up
belt slack.
(6) Remove the pin or 1/8º or 3 mm Allen wrench
from belt tensioner.
(7) Rotate crankshaft 2 revolutions and check the
alignment of the timing marks (Fig. 50).
(8) Install front half of timing cover.
(9) Install engine mount bracket.
(10) Install Right engine mount. Refer to proce-
dure outlined in this section.
(11) Remove jack from under engine.
(12) Install crankshaft damper using M12-1.75 x
150 mm bolt, washer, thrust bearing and nut from
Special Tool 6792. Install crankshaft damper bolt and
tighten to 142 N´m (105 ft. lbs.) (Fig. 39).
(13) Install accessory drive belts. Refer to Group 7,
Cooling System Accessory Drive section for proce-
dure.
(14) Raise vehicle on hoist and install right inner
splash shield.
(15) Perform camshaft and crankshaft timing
relearn procedure as follows:
²Connect the DRB scan tool to the data link
(diagnostic) connector. This connector is located in
the passenger compartment; at the lower edge of
instrument panel; near the steering column.
Fig. 39 Crankshaft DamperÐInstallation
9 - 16 ENGINENS/GS
REMOVAL AND INSTALLATION (Continued)

filter on until gasket contacts base. Tighten to 21
N´m (15 ft. lbs.).
OIL PUMP
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove Timing Belt. Refer to Timing Belt Sys-
tem, in this section.
(3) Remove Oil Pan. Refer to Oil Pan Removal in
this section.
(4) Remove Crankshaft Sprocket using Special Tool
6793 and insert C-4685-C2 (Fig. 70).
(5) Remove oil pick-up tube.
(6) Remove oil pump (Fig. 71) and front crankshaft
seal.
INSTALLATION
(1) Make sure all surfaces are clean and free of oil
and dirt.(2) Apply MopartGasket Maker to oil pump as
shown in (Fig. 72). Install o±ring into oil pump body
discharge passage.
(3) Prime oil pump before installation.
(4) Align oil pump rotor flats with flats on crank-
shaft as you install the oil pump to the block.
NOTE: Front crankshaft seal MUST be out of pump
to align, or damage may result.
(5) Torque all oil pump attaching bolts to 28 N´m
(250 in. lbs.)
(6) Install new front crankshaft seal using Special
Tool 6780 (Fig. 73).
(7) Install crankshaft sprocket, using Special Tool
6792 (Fig. 74).
(8) Install oil pump pick-up tube and oil pan.
(9) Install Timing Belt. Refer to procedure outlined
in this section.
(10) Connect negative cable to battery.
PISTON AND CONNECTING ROD
REMOVAL
(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. 75).
(2) Remove oil pan. Scribe the cylinder number on
the side of the rod and cap (Fig. 76) for identification.
(3) Pistons will have a stamping in the approxi-
mate location shown in (Fig. 75). These stamps will
be either a directional arrow or a weight identifica-
tion for the assembly. L is for light and H is for
heavy. These assemblies should all be the same
weight class. Service piston assemblies are marked
with a S and can be used with either L or H produc-
tion assemblies. The weight designation stamps
should face toward the timing belt side of the 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 connecting rod cap boltsDo not use
old bolts if reinstalling connecting rod.Push
each piston and rod assembly out of cylinder bore.
NOTE: Be careful not to nick crankshaft journals.
(6) After removal, install bearing cap on the mat-
ing rod.
(7) Piston and Rods are serviced as an assembly.
PISTON RINGÐREMOVAL
(1) ID mark on face of upper and intermediate pis-
ton rings must point toward piston crown.
Fig. 69 Engine Oil Filter
Fig. 70 Crankshaft SprocketÐRemoval
NS/GSENGINE 9 - 25
REMOVAL AND INSTALLATION (Continued)