2004 CHRYSLER VOYAGER engine

CYLINDER HEAD
DESCRIPTION
The aluminum cylinder heads (Fig. 1) 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 incorpo-
rates the combustion chamber. Two valves per-cylin-
der 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 misfiring²Poor 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.
Fig. 1 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
9s - 16 ENGINE 3.3/3.8L SUPPLEMENTRS

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.
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. 2).
(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. 6).
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.
Remove all gasket material from cylinder head and
block (Refer to 9 - ENGINE - STANDARD PROCE-
DURE). Be careful not to gouge or scratch the alumi-
num head sealing surface.
Clean all engine oil passages.
INSPECTION
(1) Before cleaning, check for leaks, damage and
cracks.
(2) Clean cylinder head and oil passages.
(3) Check cylinder head for flatness (Fig. 3).
(4) Cylinder head must be flat within:
Fig. 2 DIPSTICK & TUBE
1 - DIPSTICK
2 - BOLT
3 - TUBE
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CYLINDER HEAD (Continued)

²Standard dimension = less than 0.05 mm (0.002
inch.)
²Service Limit = 0.2 mm (0.008 inch.)
²Grinding Limit = Maximum of 0.2 mm (0.008
inch.) is permitted.
CAUTION: 0.20 mm (0.008 in.) MAX is a combined
total dimension of the stock removal limit from cyl-
inder head and block top surface (Deck) together.
INSTALLATION - CYLINDER HEAD
(1) Clean all sealing surfaces of engine block and
cylinder heads. (Refer to 9 - ENGINE - STANDARD
PROCEDURE)
(2) Position new gasket(s) on engine block (Fig. 4).
The left bank gasket is identified with the ªLº
stamped in the exposed area of the gasket located at
front of engine (shown in (Fig. 4)). The right bank
gasket is identified with a ªRº stamped in the
exposed area of the gasket also, but is located at the
rear of the engine.(3)The cylinder head bolts are torqued using
the torque yield method, they should be exam-
ined BEFORE reuse. If the threads are necked
down, the bolts must be replaced(Fig. 5).
(4) Necking can be checked by holding a scale or
straight edge against the threads. If all the threads
do not contact the scale the bolt should be replaced.
(5) Tighten the cylinder head bolts 1±8 in the
sequence shown in (Fig. 6). Using the 4 step torque
turn method, tighten according to the following val-
ues:
²Step 1: Bolts1±8to61N´m(45ft.lbs.)
²Step 2: Bolts1±8to88N´m(65ft.lbs.)
²Step 3: Bolts1±8(again) to 88 N´m (65 ft. lbs.)
²Step 4: Bolts1±8turn an additional 1/4 Turn.
(Do not use a torque wrench for this step.)
NOTE: Bolt torque after 1/4 turn should be over 122
N´m (90 ft. lbs.). If not, replace the bolt.
(6) Inspect push rods and replace worn or bent
rods.
(7) Install the push rods.
(8) Install the rocker arm and shaft assemblies.
(Refer to 9 - ENGINE/CYLINDER HEAD/ROCKER
ARMS - INSTALLATION)
(9) Install the cylinder head covers. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION)
Fig. 3 Checking Cylinder Head FlatnessÐTypical
Fig. 4 Head Gasket Installation
1 - CYLINDER HEAD GASKET
2 - LOCATION IDENTIFICATION (L = LEFT BANK, R = RIGHT
BANK)
Fig. 5 Checking Bolts for Stretching (Necking)
1 - STRETCHED BOLT
2 - THREADS ARE NOT STRAIGHT ON LINE
3 - THREADS ARE STRAIGHT ON LINE
4 - UNSTRETCHED BOLT
Fig. 6 CYLINDER HEAD TIGHTENING SEQUENCE
9s - 18 ENGINE 3.3/3.8L SUPPLEMENTRS
CYLINDER HEAD (Continued)

(10) Install the exhaust manifolds. (Refer to 9 -
ENGINE/MANIFOLDS/EXHAUST MANIFOLD -
INSTALLATION)
(11) Install new O-ring on dipstick tube. Install
dipstick tube assembly (Fig. 2).
(12) Install the spark plugs.
(13) Install upper and lower intake manifolds.
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - INSTALLATION)
(14) Fill the cooling system. (Refer to 7 - COOL-
ING - STANDARD PROCEDURE)
(15) Connect negative cable to battery.
CYLINDER HEAD COVER(S)
DESCRIPTION
The cylinder head covers are made of stamped
steel. The covers are sealed with steel reinforced sil-
icon rubber gaskets. The cylinder head cover uses
rubber isolators at each fastener location (Fig. 7).
NOTE: Due to the tight packaging near the cylinder
head covers, which makes spill clean-up difficult, a
spill during an engine oil change may be misinter-
preted as an oil leak. When investigating an oil leak
in the location of the cylinder head covers and
intake manifold, follow the procedure found in Oil
Leak Diagnosis (Refer to 9 - ENGINE - DIAGNOSIS
AND TESTING) for determining the source of a leak.
CYLINDER HEAD COVER-
RIGHT
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove the wiper module. (Refer to 8 - ELEC-
TRICAL/WIPERS/WASHERS/WIPER MODULE -
REMOVAL)
(3) Disconnect spark plug wires from plugs.
(4) Disconnect PCV hose from cylinder head cover
(Fig. 8).
(5) Remove cylinder head cover bolts.
(6) Remove cylinder head cover and gasket (Fig.
7).
INSTALLATION
(1) Clean cylinder head and cover mating surfaces.
Inspect cylinder head cover surface for flatness.
Replace gasket as necessary.
(2) Inspect seal on the cover bolt for wear or dam-
age (Fig. 9). Replace bolt assembly as necessary.
NOTE: The cylinder head cover bolts contain a
torque limiter sleeve and a seal (Fig. 9). The seal
and torque sleeve is replaced with the bolt.
Fig. 7 Cylinder Head Cover
1 - CYLINDER HEAD COVER
2 - BOLT
Fig. 8 PCV Hose
1 - HOSE - PCV
2 - P C V VA LV E
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CYLINDER HEAD (Continued)

(3) Assemble gasket to cylinder cover by inserting
the bolt assemblies through each bolt hole on the
cover and gasket (Fig. 9).
(4) Install cylinder head cover and bolts (Fig. 10).
(5) Tighten cylinder head cover bolts to 12 N´m
(105 in. lbs.) (Fig. 10).
(6) Connect PCV hose to cylinder head cover.
(7) Connect spark plug wires to spark plugs.
(8) Install wiper module. (Refer to 8 - ELECTRI-
CAL/WIPERS/WASHERS/WIPER MODULE -
INSTALLATION)
(9) Connect negative cable to battery.
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. 9).
(3) Install the cylinder head cover and bolts (Fig.
10).
(4) Tighten cylinder head cover bolts to 12 N´m
(105 in. lbs.) (Fig. 10).
(5) Connect crankcase vent hose.
(6) Connect spark plug wires to spark plugs.
Fig. 9 CYLINDER HEAD COVER GASKET
1 - CYLINDER HEAD COVER
2 - BOLT
3 - SEAL (SERVICED WITH BOLT)
4 - GASKET
Fig. 10 Cylinder Head Cover
1 - CYLINDER HEAD COVER
2 - BOLT
9s - 20 ENGINE 3.3/3.8L SUPPLEMENTRS
CYLINDER HEAD COVER-RIGHT (Continued)

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. 11).
VALVES
(1) Inspect the remaining margin after the valves
are refaced (Fig. 12). (Refer to 9 - ENGINE - SPEC-
IFICATIONS)
VALVE SEATS
CAUTION: Remove metal from valve seat only. Do
not remove material from cylinder head (Fig. 13).
(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.
Fig. 11 VALVE FACE AND SEAT
1 - VALVE FACE WIDTH
2 - VALVE FACE ANGLE
3 - SEAT ANGLE
4 - SEAT CONTACT AREA
Fig. 12 Valve Margin
1 - VALVE FACE
2 - VALVE MARGIN
Fig. 13 Refacing Valve Seats
1 - REFACING STONE MUST NOT CUT INTO CYLINDER HEAD
2-STONE
3 - PILOT
4 - SEAT
RSENGINE 3.3/3.8L SUPPLEMENT9s-21

(2) Measure the concentricity of valve seat using
dial indicator (Fig. 14). 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.
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. 11).
(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. 15). 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. 15).
If valves and/or seats are reground, measure
the installed height of springs (Fig. 15), 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.
(2) Measure valve stems for wear (Fig. 16). For
valve specifications, (Refer to 9 - ENGINE - SPECI-
FICATIONS).
NOTE: Valve stems are chrome plated and should
not be polished (Fig. 16).
Fig. 14 Measurement of Valve Seat Runout
1 - DIAL INDICATOR
Fig. 15 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)
9s - 22 ENGINE 3.3/3.8L SUPPLEMENTRS
INTAKE/EXHAUST VALVES & SEATS (Continued)

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. 17).
(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. 19).
(3) Install new seals on all valve stems and over
valve guides (Fig. 19). Install valve springs and valve
retainers (Fig. 19).
(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. 18). The springs are seated on
a steel washer on the cylinder head with retainers
and locks retaining the springs (Fig. 19). The springs
are installed with the smaller diameter against
spring retainer (Fig. 18).
OPERATION
The valve spring returns the valve against its seat
for a positive seal of the combustion chamber.
Fig. 16 Intake and Exhaust Valves
1 - MARGIN
2-FACE
3 - STEM
4 - VALVE SPRING RETAINER LOCK GROOVES
Fig. 17 Measuring Valve Guide Wear - Typical
Fig. 18 Valve Spring - Type A
1 - VALVE SPRING (TOP - SMALLER DIAMETER)
RSENGINE 3.3/3.8L SUPPLEMENT9s-23
INTAKE/EXHAUST VALVES & SEATS (Continued)