(2) Disconnect the inlet air temperature sensor
(Fig. 16).
(3) Remove the inlet hose to throttle body.
(4) Remove the bolt for air box at upper radiator
cross member.
(5) Pull air box up and off over the single locating
pin.
(6) Remove air box from vehicle
INSTALLATION
(1) Install air box into vehicle and onto the locat-
ing pin.
(2) Install bolt to hold air box to the upper radia-
tor cross member.
(3) Install the inlet hose to the throttle body.
(4) Connect the inlet air temperature sensor (Fig.
16).
(5) Connect the negative battery cable.
CYLINDER HEAD
DESCRIPTION
The aluminum cylinder heads (Fig. 17) are
designed to create high flow combustion chambers to
improve performance, while minimizing the change
to the burn rate in the chamber. The cylinder head
incorporates the combustion chamber. Two valves
per-cylinder are used with inserted valve seats and
guides. A multi-layer steel (MLS) type gasket is used
between the cylinder head and engine block.
DIAGNOSIS AND TESTINGÐCYLINDER 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
Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
²Engine overheating
²Loss of coolant
²Excessive steam (white smoke) emitting from
exhaust
²Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test (Refer
to 9 - ENGINE - DIAGNOSIS AND TESTING). An
engine cylinder head gasket leaking between adja-
cent cylinders will result in approximately a 50±70%
reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING WITH COOLANT PRES-
SURE CAP REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure
cap. Start the engine and allow it to warm up until
thermostat opens.
If a large combustion/compression pressure leak
exists, bubbles will be visible in the coolant.
COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE PRESSURE BUILT UP, BY CONTINUOUS
ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to
pressure cap neck. Start the engine and observe the
tester's pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.
Fig. 16 Inlet Air Temperature Sensor
9 - 102 ENGINE 3.3/3.8LRS
AIR CLEANER HOUSING (Continued)
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also
be checked by using Bloc-Chek Kit C-3685-A or
equivalent. Perform test following the procedures
supplied with the tool kit.
REMOVAL - CYLINDER HEAD
(1) Drain the cooling system. (Refer to 7 - COOL-
ING - STANDARD PROCEDURE)
(2) Disconnect negative cable from battery.
(3) Remove upper and lower intake manifolds.
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - REMOVAL)
WARNING: INTAKE MANIFOLD GASKET IS MADE
OF VERY THIN METAL AND MAY CAUSE PER-
SONAL INJURY, HANDLE WITH CARE.
(4) Remove the cylinder head covers. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL)
(5) Remove the spark plugs from cylinder head.(6) Remove the dipstick and tube (Fig. 18).
(7) Remove exhaust manifold(s). (Refer to 9 -
ENGINE/MANIFOLDS/EXHAUST MANIFOLD -
REMOVAL)
(8) Remove rocker arm and shaft assemblies.(Refer
to 9 - ENGINE/CYLINDER HEAD/ROCKER ARMS -
REMOVAL) Remove push rods andmark positions
to ensure installation in original locations.
(9) Remove the eight head bolts from each cylinder
head and remove cylinder heads (Fig. 22).
CLEANING
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.
NOTE: Multi-Layer Steel (MLS) head gaskets require
a scratch free sealing surface.
Fig. 17 Cylinder Head and Components
1 - VALVE LOCKS 5 - SPRING SEATS
2 - RETAINERS 6 - CYLINDER HEAD
3 - VALVE SPRINGS 7 - VALVE - EXHAUST
4 - VALVE STEM SEALS 8 - VALVE - INTAKE
RSENGINE 3.3/3.8L9 - 103
CYLINDER HEAD (Continued)
CYLINDER HEAD COVER -
LEFT
REMOVAL
(1) Disconnect spark plug wires from spark plugs.
(2) Disconnect crankcase vent hose from cylinder
head cover.
(3) Remove cylinder head cover bolts.
(4) Remove cylinder head cover and gasket.
INSTALLATION
(1) Clean cylinder head and cover mating surfaces.
Inspect cylinder head cover surface for flatness.
Replace gasket as necessary.
(2) Assemble gasket to cylinder cover by inserting
the fasteners through each bolt hole on cover and
gasket (Fig. 25).
(3) Install the cylinder head cover and bolts (Fig.
26).
(4) Tighten cylinder head cover bolts to 12 N´m
(105 in. lbs.) (Fig. 26).
(5) Connect crankcase vent hose.
(6) Connect spark plug wires to spark plugs.
INTAKE/EXHAUST VALVES &
SEATS
DESCRIPTION
The valves have chrome plated valve stems with
four-bead lock grooves. The valve stem seals are
made of Viton rubber.
OPERATION
The two valves per cylinder are opened using
hydraulic lifters, push rods, and rocker arms.
STANDARD PROCEDURE - REFACING VALVES
AND VALVE SEATS
The intake and exhaust valves and seats are
machined to specific angles (Fig. 27).
VALVES
(1) Inspect the remaining margin after the valves
are refaced (Fig. 28). (Refer to 9 - ENGINE - SPEC-
IFICATIONS)
VALVE SEATS
CAUTION: Remove metal from valve seat only. Do
not remove material from cylinder head (Fig. 29).
(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 (Fig. 30). 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. 27 VALVE FACE AND SEAT
1 - VALVE FACE WIDTH
2 - VALVE FACE ANGLE
3 - SEAT ANGLE
4 - SEAT CONTACT AREA
Fig. 28 Valve Margin
1 - VALVE FACE
2 - VALVE MARGIN
RSENGINE 3.3/3.8L9 - 107
NOTE: Valve seats which are worn or burned can
be reworked, provided that correct angle and seat
width are maintained. Otherwise cylinder head must
be replaced.
(4) When seat is properly positioned the width of
intake and exhaust seats should be 1.50±2.00 mm
(0.059±0.078 in.) (Fig. 27).
(5) After grinding the valve seats or faces, install
the valve in cylinder head and check valve installed
height by measuring from valve tip to spring seat
(Fig. 31). Remove valve from cylinder head and grind
valve tip until within specifications. Check valve tip
for scoring. The tip chamfer should be reground (if
necessary) to prevent seal damage when the valve is
installed.(6) Check the valve spring installed height after
refacing the valve and seat (Fig. 31).
If valves and/or seats are reground, measure
the installed height of springs (Fig. 31), make
sure measurements are taken from top of
spring seat to the bottom surface of spring
retainer. If height is greater than specifica-
tions, install a 0.794 mm (0.0312 in.) spacer in
head counterbore to bring spring height back
within specifications.
REMOVAL
(1) With cylinder head removed, compress valve
springs using Valve Spring Compressor Tool
C-3422-D with adapter 8464 (Refer to 9 - ENGINE -
SPECIAL TOOLS).
(2) Remove valve retaining locks.
(3) Slowly release valve spring compressor.
Remove valve spring retainer, valve spring, and valve
stem seal.
(4) Before removing valves,remove any burrs
from valve stem lock grooves to prevent dam-
age to the valve guides.Identify valves to insure
installation in original location.
CLEANING
(1) Clean all valves thoroughly and discard
burned, warped and cracked valves.
INSPECTION
VALVES
(1) Clean and inspect valves thoroughly. Replace
burned, warped and cracked valves.
Fig. 29 Refacing Valve Seats
1 - REFACING STONE MUST NOT CUT INTO CYLINDER HEAD
2-STONE
3 - PILOT
4 - SEAT
Fig. 30 Measurement of Valve Seat Runout
1 - DIAL INDICATOR
Fig. 31 Checking Valve and Spring Installed Height
1 - SPRING RETAINER
2 - VALVE INSTALLED HEIGHT* - 48.1±49.7 mm (1.89±1.95 in.)
3 - CYINDER HEAD SURFACE
4 - SPRING INSTALLED HEIGHT* - 41.1±42.7 mm (1.61±1.68 in.)
*(MEASURED FROM TOP OF SPRING SEAT)
9 - 108 ENGINE 3.3/3.8LRS
INTAKE/EXHAUST VALVES & SEATS (Continued)
(2) Measure valve stems for wear (Fig. 32). For
valve specifications, (Refer to 9 - ENGINE - SPECI-
FICATIONS).
NOTE: Valve stems are chrome plated and should
not be polished (Fig. 32).
VALVE GUIDES
(1) Remove carbon and varnish deposits from
inside of valve guides with a reliable guide cleaner.
(2) Measure valve stem-to-guide clearance as fol-
lows:
(3) Install valve into cylinder head so it is 15 mm
(0.590 inch.) off the valve seat. A small piece of hose
may be used to hold valve in place.
(4) Attach dial indicator Tool C-3339 to cylinder
head and set it at right angle of valve stem being
measured (Fig. 33).
(5) Move valve to and from the indicator. For cler-
ance specifications, (Refer to 9 - ENGINE - SPECIFI-
CATIONS).
NOTE: Replace cylinder head if stem-to-guide clear-
ance exceeds specifications, or if guide is loose in
cylinder head.
INSTALLATION
(1) Coat valve stems with clean engine oil and
insert them in cylinder head.
(2) Install valve spring seat on head (Fig. 35).
(3) Install new seals on all valve stems and over
valve guides (Fig. 35). Install valve springs and valve
retainers (Fig. 35).(4) Install the valve springs. (Refer to 9 -
ENGINE/CYLINDER HEAD/VALVE SPRINGS -
INSTALLATION)
VALVE SPRINGS
DESCRIPTION
There are two interchangeable, floating (spring
rotates during operation), valve spring designs. Type
A may be identified by the counterclockwise (spring
spirals down and to the left) appearance, And Type B
may be identified by the clockwise (spring spirals
down and to the right) appearance. Both of the valve
springs are a bee-hive shaped design but have differ-
ent specifications (Fig. 34). The springs are seated on
a steel washer on the cylinder head with retainers
and locks retaining the springs (Fig. 35). The springs
are installed with the smaller diameter against
spring retainer (Fig. 34).
OPERATION
The valve spring returns the valve against its seat
for a positive seal of the combustion chamber.
REMOVAL
REMOVAL - CYLINDER HEAD OFF
(1) With the cylinder head on a bench, position
Special Tool C-3422-D with 8464 Adapter on the
valve and spring retainer (Fig. 36).
(2) Compress the spring only enough to remove the
valve retainer locks.
(3) Slowly release the spring tension and remove
the valve spring and retainer.
(4) For removal of the valve stem seal (Refer to 9 -
ENGINE/CYLINDER HEAD/VALVE STEM SEALS -
REMOVAL).
Fig. 32 Intake and Exhaust Valves
1 - MARGIN
2-FACE
3 - STEM
4 - VALVE SPRING RETAINER LOCK GROOVES
Fig. 33 Measuring Valve Guide Wear - Typical
RSENGINE 3.3/3.8L9 - 109
INTAKE/EXHAUST VALVES & SEATS (Continued)
Fig. 34 Valve Spring - Type A
1 - VALVE SPRING (TOP - SMALLER DIAMETER)
Fig. 35 VALVE COMPONENTS
1 - VALVE LOCKS 5 - SPRING SEATS
2 - RETAINERS 6 - CYLINDER HEAD
3 - VALVE SPRINGS 7 - VALVE - EXHAUST
4 - VALVE STEM SEALS 8 - VALVE - INTAKE
Fig. 36 VALVE SPRING - REMOVE/INSTALL
1 - SPECIAL TOOL C-3422-D SPRING COMPRESSOR
2 - SPECIAL TOOL 8464 ADAPTER
9 - 110 ENGINE 3.3/3.8LRS
VALVE SPRINGS (Continued)
CRANKSHAFT REAR OIL SEAL
RETAINER
REMOVAL
(1) Remove crankshaft rear oil seal (Refer to 9 -
ENGINE/ENGINE BLOCK/CRANKSHAFT OIL
SEAL - REAR - REMOVAL).
(2) Remove oil pan (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PAN - REMOVAL).
(3) Remove oil seal retainer screws (Fig. 83).
(4) Remove oil seal retainer (Fig. 83).
(5) Clean engine block and retainer of oil and gas-
ket material. Make sure surfaces are clean and free
of oil.
INSTALLATION
(1) Position new gasket and install retainer on
block (Fig. 83). Tighten attaching screws to 12 N´m
(105 in. lbs.).
(2) Install oil pan (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PAN - INSTALLATION).
(3) Install oil seal (Refer to 9 - ENGINE/ENGINE
BLOCK/CRANKSHAFT OIL SEAL - REAR -
INSTALLATION).
VIBRATION DAMPER
REMOVAL
(1) Disconnect negative cable from battery.
(2) Raise vehicle on hoist.
(3) Remove the right front wheel and inner splash
shield.
(4) Remove the accessory drive belt. (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL)
(5) Remove vibration damper bolt.
(6) Insert Special Tool 8450 into crankshaft nose
(Fig. 84).
(7) Position 3-jaw puller Special Tool 1026 on
damper as shown in (Fig. 84). Turn puller forcing
screw until damper releases from crankshaft.
(8) Remove the crankshaft vibration damper.
INSTALLATION
(1) Install crankshaft vibration damper using the
forcing screw, nut, and thrust bearing/washer from
Special Tool 8452 (Fig. 85).
NOTE: To minimize friction and prolong tool life,
lubricate the threads on the forcing screw of Spe-
cial Tool 8452.
(2) Position vibration damper on crankshaft.
(3) Screw Special Tool 8452 into crankshaft until
the bolt seats. Turn the nut to install damper until it
seats fully.
(4) Remove Special Tool 8452.
(5) Install vibration damper bolt. Torque bolt to 54
N´m (40 ft. lbs.).
Fig. 82 Rear Crankshaft Oil SealÐInstallation
1 - SPECIAL TOOLS:
2 - C-4171 HANDLE
3 - 6926±2 INSTALLER
4 - 6926±1 GUIDE
5 - SEAL
Fig. 83 CRANKSHAFT REAR OIL SEAL
1 - OIL SEAL
2 - BOLT
3 - RETAINER - OIL SEAL
4 - GASKET
9 - 132 ENGINE 3.3/3.8LRS
CRANKSHAFT OIL SEAL - REAR (Continued)
INSTALLATION
INSTALLATION - CRANKSHAFT SPROCKET
(1) Position the sprocket on the crankshaft (timing
mark out) with the timing slot aligned with the tim-
ing pin.
(2) Install sprocket using Special Tool 8452 (Fig.
143). Install sprocket until it is fully seats on the
crankshaft.(3) Install the timing chain and camshaft sprocket.
(Refer to 9 - ENGINE/VALVE TIMING/TIMING
BELT/CHAIN AND SPROCKETS - INSTALLATION)INSTALLATION - TIMING CHAIN AND
CAMSHAFT SPROCKET
(1) Rotate crankshaft so the timing arrow is to the
12 o'clock position (Fig. 141).
NOTE: Lubricate timing chain and sprockets with
clean engine oil before installation.
(2) While holding camshaft sprocket and chain in
hand, place timing chain around the sprocket, align-
ing the plated link with the dot on the sprocket. Posi-
tion the timing arrow to the 6 o'clock position (Fig.
141).
(3) Place timing chain around crankshaft sprocket
with the plated link lined up with the dot on the
sprocket. Install camshaft sprocket into position.
(4) Use a straight edge to check alignment of tim-
ing marks.
(5) Install camshaft sprocket bolt and washer.
Tighten bolt to 54 N´m (40 ft. lbs.).
(6) Rotate crankshaft 2 revolutions and check tim-
ing mark alignment (Fig. 141). If timing marks do
not line up, remove camshaft sprocket and realign.
(7) Install the timing chain cover. (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION)
(8) Connect negative cable to battery.
Fig. 143 CRANKSHAFT SPROCKET - INSTALLATION
1 - SPECIAL TOOL 8452-3
2 - SPECIAL TOOL 8452-1
3 - CRANKSHAFT SPROCKET
4 - THRUST BEARING / WASHER
9 - 160 ENGINE 3.3/3.8LRS
TIMING CHAIN AND SPROCKETS (Continued)