spark plugs replace CHRYSLER VOYAGER 2004 Owner's Manual

(3) Remove torque converter or clutch housing
cover and inspect rear of block for evidence of oil.
Use a black light to check for the oil leak. If a leak is
present in this area, remove transmission for further
inspection.
(a) Circular spray pattern generally indicates
seal leakage or crankshaft damage.
(b) Where leakage tends to run straight down,
possible causes are a porous block, oil gallery cup
plug, bedplate to cylinder block mating surfaces
and seal bore. See proper repair procedures for
these items.
(4) If no leaks are detected, pressurize the crank-
case as previously described.
CAUTION: Do not exceed 20.6 kPa (3 psi).
(5) If the leak is not detected, very slowly turn the
crankshaft and watch for leakage. If a leak is
detected between the crankshaft and seal while
slowly turning the crankshaft, it is possible the
crankshaft seal surface is damaged. The seal area on
the crankshaft could have minor nicks or scratches
that can be polished out with emery cloth.
CAUTION: Use extreme caution when crankshaft
polishing is necessary to remove minor nicks and
scratches. The crankshaft seal flange is especially
machined to complement the function of the rear oil
seal.
(6) For bubbles that remain steady with shaft
rotation, no further inspection can be done until dis-
assembled.
(7) After the oil leak root cause and appropriate
corrective action have been identified, replace compo-
nent(s) as necessary.
DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE TEST
The results of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise the indicated compression pressures may
not be valid for diagnosis purposes.
(1) Check engine oil level and add oil if necessary.
(2) Drive the vehicle until engine reaches normal
operating temperature. Select a route free from traf-
fic and other forms of congestion, observe all traffic
laws, and accelerate through the gears several times
briskly.
(3) Remove all spark plugs from engine. As spark
plugs are being removed, check electrodes for abnor-
mal firing indicators fouled, hot, oily, etc. Record cyl-
inder number of spark plug for future reference.(4) Remove the Auto Shutdown (ASD) relay from
the PDC.
(5) Be sure throttle blade is fully open during the
compression check.
(6) Insert compression gauge adaptor Special Tool
8116 or the equivalent, into the #1 spark plug hole in
cylinder head. Connect the 0±500 psi (Blue) pressure
transducer (Special Tool CH7059) with cable adap-
tors to the DRBIIIt. For Special Tool identification,
(Refer to 9 - ENGINE - SPECIAL TOOLS).
(7) Crank engine until maximum pressure is
reached on gauge. Record this pressure as #1 cylin-
der pressure.
(8) Repeat the previous step for all remaining cyl-
inders.
(9) Compression should not be less than 689 kPa
(100 psi) and not vary more than 25 percent from cyl-
inder to cylinder.
(10) If one or more cylinders have abnormally low
compression pressures, repeat the compression test.
(11) If the same cylinder or cylinders repeat an
abnormally low reading on the second compression
test, it could indicate the existence of a problem in
the cylinder in question.The recommended com-
pression pressures are to be used only as a
guide to diagnosing engine problems. An engine
should not be disassembled to determine the
cause of low compression unless some malfunc-
tion is present.
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE TEST
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
²Exhaust and intake valve leaks (improper seat-
ing).
²Leaks between adjacent cylinders or into water
jacket.
²Any causes for combustion/compression pressure
loss.
WARNING: DO NOT REMOVE THE PRESSURE CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM COOLANT CAN
OCCUR.
Check the coolant level and fill as required. DO
NOT install the pressure cap.
Start and operate the engine until it attains nor-
mal operating temperature, then turn the engine
OFF.
Clean spark plug recesses with compressed air.
Remove the spark plugs.
Remove the oil filler cap.
Remove the air cleaner.
RSENGINE 3.3/3.8L9-83
ENGINE 3.3/3.8L (Continued)

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)
(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. 18).
(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. 23).
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. 24).
(5) Remove cylinder head cover bolts.
(6) Remove cylinder head cover and gasket (Fig.
23).
Fig. 21 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. 22 CYLINDER HEAD TIGHTENING SEQUENCE
Fig. 23 Cylinder Head Cover
1 - CYLINDER HEAD COVER
2 - BOLT
9 - 102 ENGINE 3.3/3.8LRS
CYLINDER HEAD (Continued)

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. 25). Replace bolt assembly as necessary.
NOTE: The cylinder head cover bolts contain a
torque limiter sleeve and a seal (Fig. 25). The seal
and torque sleeve is replaced with the bolt.
(3) Assemble gasket to cylinder cover by inserting
the bolt assemblies through each bolt hole on the
cover and gasket (Fig. 25).
(4) Install cylinder head cover and bolts (Fig. 26).
(5) Tighten cylinder head cover bolts to 12 N´m
(105 in. lbs.) (Fig. 26).
(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.
Fig. 24 PCV Hose
1 - HOSE - PCV
2 - P C V VA LV E
Fig. 25 CYLINDER HEAD COVER GASKET
1 - CYLINDER HEAD COVER
2 - BOLT
3 - SEAL (SERVICED WITH BOLT)
4 - GASKET
Fig. 26 Cylinder Head Cover
1 - CYLINDER HEAD COVER
2 - BOLT
RSENGINE 3.3/3.8L9 - 103
CYLINDER HEAD COVER - RIGHT (Continued)

(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.
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.
Fig. 27 Valve Face and Seat
1 - SEAT WIDTH
2 - FACE ANGLE
3 - SEAT ANGLE
4 - SEAT CONTACT AREA
Fig. 28 Valve Margin
1 - VALVE FACE
2 - VALVE MARGIN
Fig. 29 Refacing Valve Seats
1 - REFACING STONE MUST NOT CUT INTO CYLINDER HEAD
2-STONE
3 - PILOT
4 - SEAT
9 - 104 ENGINE 3.3/3.8LRS
CYLINDER HEAD COVER - LEFT (Continued)

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
The valve springs are a bee-hive shaped design
(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).
REMOVAL - CYLINDER HEAD ON
(1) Disconnect negative cable from battery.
(2) Remove spark plug wires and all spark plugs.
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
Fig. 34 Valve Spring
1 - VALVE SPRING (TOP - SMALLER DIAMETER)
9 - 106 ENGINE 3.3/3.8LRS
INTAKE/EXHAUST VALVES & SEATS (Continued)

(11) Repeat procedure for each cylinder requiring
valve spring removal.
INSPECTION
Whenever valves have been removed for inspection,
reconditioning or replacement, valve springs should
be tested (Fig. 38).As an example;the compression
length of a spring to be tested is 38.00 mm (1.496
in.). Turn the table of Tool C-647 until surface is in
line with the 38.00 mm (1.496 in.) mark on the
threaded stud and the zero mark on the front. Place
spring over stud on the table and lift compressing
lever to set tone device. Pull on torque wrench until
ping is heard. Take reading on torque wrench at this
instant. Multiply this reading by two. This will give
the spring load at test length. Fractional measure-
ments are indicated on the table for finer adjust-
ments. Refer to Engine Specifications to obtain
specified height and allowable tensions (Refer to 9 -
ENGINE - SPECIFICATIONS). Replace any springs
that do not meet specifications.
INSTALLATION
INSTALLATION - CYLINDER HEAD OFF
(1) If removed, install a new valve stem seal (Refer
to 9 - ENGINE/CYLINDER HEAD/VALVE STEM
SEALS - INSTALLATION).
(2) Position valve spring and retainer on spring
seat.(3) Using Special Tool C-3422-D with 8464 Adapter
(Fig. 36), compress the spring only enough to install
the valve retainer locks. Install valve retainer locks.
(4) Slowly release the spring tension. Ensure the
retainer locks are seated properly.
INSTALLATION - CYLINDER HEAD ON
(1) The intake valve stem seals should be pushed
firmly and squarely over the valve guide using the
valve stem as guide.Do Not Forceseal against top
of guide. When installing the valve retainer locks,
compress the springonly enoughto install the
locks.
CAUTION: Do not pinch seal between retainer and
top of valve guide.
(2) Follow the same procedure on the remaining 5
cylinders using the firing sequence 1-2-3-4-5-6.Make
sure piston in cylinder is at TDC on the valve
spring that is being covered.
(3) Remove spark plug adapter tool.
(4) Install rocker arms and shaft assembly. (Refer
to 9 - ENGINE/CYLINDER HEAD/ROCKER ARMS -
INSTALLATION)
(5) Install cylinder head covers. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION)
(6) Install spark plugs and connect wires.
(7) Connect negative cable to battery.
Fig. 37 VALVE SPRING - REMOVE/INSTALL (HEAD
ON)
1 - SPECIAL TOOL 8453
2 - BOLTS - SPECIAL TOOL ATTACHING
3 - AIR SUPPLY HOSE ADAPTER
Fig. 38 TESTING VALVE SPRING
1 - SPECIAL TOOL C-647
9 - 108 ENGINE 3.3/3.8LRS
VALVE SPRINGS (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
RSENGINE 3.3/3.8L SUPPLEMENT9s-19
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)

The combustion reaction caused by the catalyst
releases additional heat in the exhaust system, caus-
ing temperature increases in the area of the reactor
under severe operating conditions. Such conditions
can exist when the engine misfires or otherwise does
not operate at peak efficiency.Do notremove spark
plug wires from plugs or by any other means short
out cylinders, if exhaust system is equipped with a
catalytic converter. Failure of the catalytic converter
can occur due to temperature increases caused by
unburned fuel passing through the converter. This
deterioration of the catalyst core can result in exces-
sively high emission levels, noise complaints, and
exhaust restrictions.
Unleaded gasoline must be used to avoid ruining
the catalyst core. Do not allow engine to operate
above 1200 RPM in neutral for extended periods over
5 minutes. This condition may result in excessive
exhaust system/floor pan temperatures because of no
air movement under the vehicle.
The flex joint allows flexing as the engine moves,
preventing breakage that could occur from the back-
and-forth motion of a transverse mounted engine.
CAUTION: Due to exterior physical similarities of
some catalytic converters with pipe assemblies,
extreme care should be taken with replacement
parts. There are internal converter differences
required in some parts of the country (particularly
vehicles built for States with strict emission
requirements) and between model years.
REMOVAL
(1) Loosen clamp and disconnect the muffler/reso-
nator assembly from catalytic converter pipe.
(2) Disconnect downstream oxygen sensor electri-
cal connector (Fig. 4). For removal of downstream
oxygen sensor, (Refer to 14 - FUEL SYSTEM/FUEL
INJECTION/O2 SENSOR - REMOVAL).
(3) Remove catalytic converter to exhaust manifold
attaching fasteners (Fig. 5).
(4) Remove catalytic converter and gasket (Fig. 5).
INSPECTION
WARNING: THE NORMAL OPERATING TEMPERA-
TURE OF THE EXHAUST SYSTEM IS VERY HIGH.
THEREFORE, NEVER ATTEMPT TO SERVICE ANY
PART OF THE EXHAUST SYSTEM UNTIL IT IS
COOLED. SPECIAL CARE SHOULD BE TAKEN
WHEN WORKING NEAR THE CATALYTIC CON-
VERTER. THE TEMPERATURE OF THE CONVERTER
RISES TO A HIGH LEVEL AFTER A SHORT PERIOD
OF ENGINE OPERATION TIME.Check catalytic converter for a flow restriction.
(Refer to 11 - EXHAUST SYSTEM - DIAGNOSIS
AND TESTING) Exhaust System Restriction Check
for procedure.
Fig. 4 Downstream Oxygen Sensor
1 - OXYGEN SENSOR CONNECTOR
2 - CATALYTIC CONVERTER
3 - DOWNSTREAM OXYGEN SENSOR
4 - ENGINE HARNESS CONNECTOR
Fig. 5 Catalytic Converter to Exhaust Manifold
1 - FLAG NUT
2 - GASKET
3 - BOLT
4 - CATALYTIC CONVERTER
RSEXHAUST SYSTEM11-5
CATALYTIC CONVERTER (Continued)