2003 CHRYSLER CARAVAN coolant

INTAKE MANIFOLD - LOWER
REMOVAL
(1) Perform fuel system pressure release proce-
durebefore attempting any repairs.(Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY - STANDARD
PROCEDURE)
(2) Remove upper intake manifold. (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL)
CAUTION: Cover intake manifold openings to pre-
vent foreign material from entering engine.
(3) Disconnect fuel line. (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/QUICK CONNECT FIT-
TING - STANDARD PROCEDURE)
(4) Drain the cooling system. (Refer to 7 - COOL-
ING - STANDARD PROCEDURE)
(5) Remove heater supply and radiator upper
hoses at intake manifold.
(6) Disconnect coolant temperature sensor/fuel
injector wire harness connector.
(7) Remove lower intake manifold support bracket
upper bolts (Fig. 107).
(8) Loosen the lower intake manfold support
bracket lower bolt (Fig. 107).
(9) Disconnect fuel injector harness.
(10) Remove the bolts attaching the power steering
reservoir to manifold. Set reservoir aside.Do not
disconnect line from reservoir.
(11) Remove lower intake manifold fasteners (Fig.
108). Remove the manifold from engine.
(12) Inspect the manifold. (Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - INSPECTION)
INSPECTION
(1) Check manifold surfaces for flatness with
straight edge. Surface must be flat within 0.15 mm
per 300 mm (0.006 in. per foot) of manifold length.
(2) Inspect manifold for cracks or distortion.
Replace manifold if necessary.
INSTALLATION
If the following items were removed, install and
torque to specifications:
²Fuel rail bolts - 22 N´m (200 in. lbs.)
²Coolant outlet connector bolts - 28 N´m (250 in.
lbs.)
²Coolant temperature sensor - 7 N´m (60 in. lbs.)
(1) Position a new gasket on cylinder head and
install lower manifold.
(2) Install and tighten intake manifold fasteners to
28 N´m (250 in. lbs.) in the sequence shown in (Fig.
108). Repeat procedure until all bolts are at specified
torque.
(3) Install lower intake manifold support bracket
bolts (Fig. 107) and tighten to:
²Bolts to intake 28 N´m (250 in. lbs.)
²Bolt to engine block 54 N´m (40 ft. lbs.)
(4) Position power steering reservoir on manifold
and install bolts.
(5) Connect the fuel line. (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/QUICK CONNECT FIT-
TING - STANDARD PROCEDURE)
(6) Connect coolant temperature sensor/fuel injec-
tor wiring harness electrical connector.
(7) Install the radiator upper and heater supply
hoses.
(8) Install the upper intake manifold. (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSTALLATION)
(9) Fill the cooling system. (Refer to 7 - COOLING
- STANDARD PROCEDURE)
Fig. 107 Lower Intake Manifold Support Bracket
1 - SUPPORT BRACKET
2 - BOLTS - UPPER TO MANIFOLD
3 - BOLT - LOWER TO ENGINE BLOCK
Fig. 108 Lower Intake Manifold Tightening
Sequence
9 - 60 ENGINE 2.4LRS
ProCarManuals.com

CAUTION: When aligning crankshaft and camshaft
timing marks always rotate engine from crankshaft.
Camshaft should not be rotated after timing belt is
removed. Damage to valve components may occur.
Always align timing marks before removing timing
belt.
(14) Before the removal of the timing belt, rotate
crankshaft until the TDC mark on oil pump housing
aligns with the TDC mark on crankshaft sprocket
(trailing edge of sprocket tooth) (Fig. 116).
NOTE: The crankshaft sprocket TDC mark is
located on the trailing edge of the sprocket tooth.
Failure to align trailing edge of sprocket tooth to
TDC mark on oil pump housing will cause the cam-
shaft timing marks to be misaligned.
(15) Loosen timing belt tensioner lock bolt (Fig.
117).
(16) Inserta6mmAllen wrench into the hexagon
opening located on the top plate of the belt tensioner
pulley (Fig. 117). Rotate the top plateCLOCKWISE
until there is enough slack in timing belt to allow for
removal.
(17) Remove timing belt.CAUTION: If timing belt was damaged due to incor-
rect tracking (alignment), the belt tensioner pulley
and bracket must be replaced as an assembly
(Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT
TENSIONER & PULLEY - REMOVAL).
REMOVAL - CAMSHAFT SPROCKETS
(1) Disconnect negative battery cable.
(2) Remove timing belt (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT AND SPROCKETS -
REMOVAL).
(3) Hold camshaft sprockets with Special Tool 6847
while removing center bolts (Fig. 118).
REMOVAL - CRANKSHAFT SPROCKET
(1) Disconnect negative battery cable.
(2) Remove timing belt (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT AND SPROCKETS -
REMOVAL).
(3) Remove crankshaft sprocket using Special
Tools 6793 and insert C-4685-C2 (Fig. 119).
CLEANING
Do Not attempt to clean a timing belt. If contami-
nation from oil, grease, or coolants have occurred, the
timing belt should be replaced.
Clean all sprockets using a suitable solvent. Clean
all sprocket grooves of any debris.
Fig. 116 Crankshaft and Camshaft Timing
1 - CAMSHAFT TIMING MARKS
2 - CRANKSHAFT TDC MARKS
3 - TRAILING EDGE OF SPROCKET TOOTH
Fig. 117 Timing Belt Tensioner
1 - LOCK BOLT
2 - TOP PLATE
9 - 64 ENGINE 2.4LRS
TIMING BELT AND SPROCKET(S) (Continued)
ProCarManuals.com

(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)
ProCarManuals.com

Calibrate the tester according to the manufactur-
er's instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1,379
kPa (200 psi) maximum, with 552 kPa (80 psi) rec-
ommended.
Perform the test procedures on each cylinder
according to the tester manufacturer's instructions.
While testing, listen for pressurized air escaping
through the throttle body, tailpipe and oil filler cap
opening. Check for bubbles in the coolant.
All gauge pressure indications should be equal,
with no more than 25% leakage per cylinder.
FOR EXAMPLE:At 552 kPa (80 psi) input pres-
sure, a minimum of 414 kPa (60 psi) should be main-
tained in the cylinder.
STANDARD PROCEDURE
STANDARD PROCEDURE - MEASURING
BEARING CLEARANCE USING PLASTIGAGE
Engine crankshaft bearing clearances can be deter-
mined by use of Plastigage or equivalent. The follow-
ing is the recommended procedure for the use of
Plastigage:
(1) Remove oil film from surface to be checked.
Plastigage is soluble in oil.
(2) Place a piece of Plastigage across the entire
width of the bearing shell in the cap approximately
6.35 mm (1/4 in.) off center and away from the oil
holes (Fig. 3). (In addition, suspected areas can be
checked by placing the Plastigage in the suspected
area). Torque the bearing cap bolts of the bearing
being checked to the proper specifications.
(3) Remove the bearing cap and compare the
width of the flattened Plastigage with the metric
scale provided on the package. Locate the band clos-est to the same width. This band shows the amount
of clearance in thousandths of a millimeter. Differ-
ences in readings between the ends indicate the
amount of taper present. Record all readings taken.
Compare clearance measurements to specs found in
engine specifications (Refer to 9 - ENGINE - SPECI-
FICATIONS).Plastigage generally is accompa-
nied by two scales. One scale is in inches, the
other is a metric scale.
NOTE: Plastigage is available in a variety of clear-
ance ranges. Use the most appropriate range for
the specifications you are checking.
(4) Install the proper crankshaft bearings to
achieve the specified bearing clearances.
STANDARD PROCEDURE - FORM-IN-PLACE
GASKETS AND SEALERS
There are numerous places where form-in-place
gaskets are used on the engine. Care must be taken
when applying form-in-place gaskets to assure
obtaining the desired results.Do not use form-in-
place gasket material unless specified.Bead size,
continuity, and location are of great importance. Too
thin a bead can result in leakage while too much can
result in spill-over which can break off and obstruct
fluid feed lines. A continuous bead of the proper
width is essential to obtain a leak-free gasket.
There are numerous types of form-in-place gasket
materials that are used in the engine area. Mopart
Engine RTV GEN II, MopartATF-RTV, and Mopart
Gasket Maker gasket materials, each have different
properties and can not be used in place of the other.
MOPARtENGINE RTV GEN IIis used to seal
components exposed to engine oil. This material is a
specially designed black silicone rubber RTV that
retains adhesion and sealing properties when
exposed to engine oil. Moisture in the air causes the
material to cure. This material is available in three
ounce tubes and has a shelf life of one year. After one
year this material will not properly cure. Always
inspect the package for the expiration date before
use.
MOPARtATF RTVis a specifically designed
black silicone rubber RTV that retains adhesion and
sealing properties to seal components exposed to
automatic transmission fluid, engine coolants, and
moisture. This material is available in three ounce
tubes and has a shelf life of one year. After one year
this material will not properly cure. Always inspect
the package for the expiration date before use.
MOPARtGASKET MAKERis an anaerobic type
gasket material. The material cures in the absence of
air when squeezed between two metallic surfaces. It
will not cure if left in the uncovered tube. The
Fig. 3 Plastigage Placed in Lower ShellÐTypical
1 - PLASTIGAGE
9 - 84 ENGINE 3.3/3.8LRS
ENGINE 3.3/3.8L (Continued)
ProCarManuals.com

anaerobic material is for use between two machined
surfaces. Do not use on flexible metal flanges.
MOPARtBED PLATE SEALANTis a unique
(green-in-color) anaerobic type gasket material that
is specially made to seal the area between the bed-
plate and cylinder block without disturbing the bear-
ing clearance or alignment of these components. The
material cures slowly in the absence of air when
torqued between two metallic surfaces, and will rap-
idly cure when heat is applied.
MOPARtGASKET SEALANTis a slow drying,
permanently soft sealer. This material is recom-
mended for sealing threaded fittings and gaskets
against leakage of oil and coolant. Can be used on
threaded and machined parts under all tempera-
tures. This material is used on engines with multi-
layer steel (MLS) cylinder head gaskets. This
material also will prevent corrosion. MopartGasket
Sealant is available in a 13 oz. aerosol can or 4oz./16
oz. can w/applicator.
SEALER APPLICATION
MopartGasket Maker material should be applied
sparingly 1 mm (0.040 in.) diameter or less of sealant
to one gasket surface. Be certain the material sur-
rounds each mounting hole. Excess material can eas-
ily be wiped off. Components should be torqued in
place within 15 minutes. The use of a locating dowel
is recommended during assembly to prevent smear-
ing material off the location.
MopartEngine RTV GEN II or ATF RTV gasket
material should be applied in a continuous bead
approximately 3 mm (0.120 in.) in diameter. All
mounting holes must be circled. For corner sealing, a
3.17 or 6.35 mm (1/8 or 1/4 in.) drop is placed in the
center of the gasket contact area. Uncured sealant
may be removed with a shop towel. Components
should be torqued in place while the sealant is still
wet to the touch (within 10 minutes). The usage of a
locating dowel is recommended during assembly to
prevent smearing material off the location.
MopartGasket Sealant in an aerosol can should be
applied using a thin, even coat sprayed completely
over both surfaces to be joined, and both sides of a
gasket. Then proceed with assembly. Material in a
can w/applicator can be brushed on evenly over the
sealing surfaces. Material in an aerosol can should be
used on engines with multi-layer steel gaskets.
STANDARD PROCEDURE - ENGINE GASKET
SURFACE PREPARATION
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.Neveruse the following to clean gasket surfaces:
²Metal scraper
²Abrasive pad or paper to clean cylinder block
and head
²High speed power tool with an abrasive pad or a
wire brush (Fig. 4)
NOTE: Multi-Layer Steel (MLS) head gaskets require
a scratch free sealing surface.
Only use the following for cleaning gasket surfaces:
²Solvent or a commercially available gasket
remover
²Plastic or wood scraper (Fig. 4)
²Drill motor with 3M RolocŸ Bristle Disc (white
or yellow) (Fig. 4)
CAUTION: Excessive pressure or high RPM (beyond
the recommended speed), can damage the sealing
surfaces. The mild (white, 120 grit) bristle disc is
recommended. If necessary, the medium (yellow, 80
grit) bristle disc may be used on cast iron surfaces
with care.
STANDARD PROCEDURE - HYDROSTATIC
LOCKED ENGINE
When an engine is suspected to be hydrostatically
locked, regardless of what caused the problem, the
following steps should be used.
CAUTION: DO NOT use starter motor to rotate the
engine, severe damage may occur.
Fig. 4 Proper Tool Usage For Surface Preparation
1 - ABRASIVE PAD
2 - 3M ROLOCŸ BRISTLE DISC
3 - PLASTIC/WOOD SCRAPER
RSENGINE 3.3/3.8L9-85
ENGINE 3.3/3.8L (Continued)
ProCarManuals.com

(11) Disconnect the throttle cables from the throt-
tle body.
(12) Disconnect the MAP, IAC, and TPS electrical
connectors.
(13) Disconnect the EGR transducer electrical con-
nector (if equipped).
(14) Disconnect the vacuum hoses from throttle
body.
(15) Disconnect the brake booster and speed con-
trol vacuum hoses.
(16) Disengage wire harness clip from the right
side engine mount.
(17) Remove the power steering reservoir from
mounting position and set aside.Do notdisconnect
hose.
(18) Disconnect ground strap from rear of cylinder
head.
(19) Disconnect engine coolant temperature (ECT)
sensor and ignition coil electrical connectors.
(20) Disconnect the fuel injector electrical harness
connector and disengage clip from support bracket.
(21) Disconnect camshaft and crankshaft position
sensor electrical connectors.
(22) Evacuate air conditioning system. Refer to 24
- HEATING & AIR CONDITIONING.
(23) Disconnect A/C compressor electrical connec-
tor.
(24) Disconnect the A/C lines from compressor.
Cover and seal all openings of hoses and compressor.
(25) Remove the radiator upper hose.
(26) Disengage electrical harness clip at transaxle
dipstick tube.
(27) Remove transaxle dipstick tube. Seal opening
using a suitable plug.
NOTE: When the transaxle cooler lines are removed
from the rolled-groove type fittings at the transaxle,
damage to the inner wall of the hose will occur. To
prevent prevent potential leakage, the cooler hoses
must be cut off flush at the transaxle fitting, and a
service cooler hose splice kit must be installed
upon reassembly.
(28) Using a blade or suitable hose cutter, cut
transaxle oil cooler lines off flush with fittings. Plug
cooler lines and fittings to prevent debris from enter-
ing transaxle or cooler circuit. A service splice kit will
be installed upon reassembly.
(29) Disconnect transaxle shift linkage and electri-
cal connectors.
(30)
Raise vehicle on hoist and drain the engine oil.
(31) Remove the axle shafts. (Refer to 3 - DIFFER-
ENTIAL & DRIVELINE/HALF SHAFT - REMOVAL)
(32) Remove crossmember cradle plate (Fig. 6).
(33)AWD equipped:Remove the power transfer
unit (PTU) (Refer to 21 - TRANSMISSION/TRANS-
AXLE/POWER TRANSFER UNIT - REMOVAL).(34) Disconnect exhaust pipe from the manifold
(Fig. 7).
(35) Remove front engine mount and bracket as an
assembly.
(36) Remove the engine rear mount bracket.
(37) Remove the engine to transaxle struts (Fig. 8).
(38) Remove transaxle case cover (Fig. 8).
(39) Remove flex plate to torque converter bolts.
Mark torque converter to flex plate for orientation for
reassembly.
(40) Remove the power steering pressure hose sup-
port clip attaching bolt.
Fig. 6 Crossmember Cradle Plate
1 - CRADLE PLATE
Fig. 7 Catalytic Converter to Exhaust Manifold
1 - FLAG NUT
2 - GASKET
3 - BOLT
4 - CATALYTIC CONVERTER
RSENGINE 3.3/3.8L9-87
ENGINE 3.3/3.8L (Continued)
ProCarManuals.com

(8) Install the generator and wiring harness (Refer
to 8 - ELECTRICAL/CHARGING/GENERATOR -
INSTALLATION).
(9) Raise vehicle.
(10) Attach wiring harness support clip to the
engine oil dipstick tube.
(11) Connect oil pressure switch electrical connec-
tor.
(12) Install the A/C compressor.
(13) Install the water pump pulley.
(14) Connect the radiator lower hose.(15) Install the accessory drive belt and splash
shield (Refer to 7 - COOLING/ACCESSORY DRIVE/
DRIVE BELTS - INSTALLATION).
(16) Connect the engine block heater electrical con-
nector (if equipped).
(17) Connect the knock sensor electrical connector
(3.8L only).
(18) Install the torque converter to flex plate bolts.
(19) Install the transaxle case cover (Fig. 8).
(20) Install the powertrain struts (Fig. 8).
(21) Install the engine rear mount bracket.
(22) Install the engine front mount and bracket
assembly.
(23)AWD equipped;Install the power transfer
unit (PTU) (Refer to 21 - TRANSMISSION/TRANS-
AXLE/POWER TRANSFER UNIT - INSTALLA-
TION).
(24) Install the axle shafts (Refer to 3 - DIFFER-
ENTIAL & DRIVELINE/HALF SHAFT - INSTALLA-
TION).
(25) Connect exhaust pipe to manifold (Fig. 7).
(26) Install crossmember cradle plate (Fig. 6).
(27) Lower vehicle.
(28) Connect transaxle shift linkage.
(29) Connect transaxle electrical connectors.
(30) Remove plugs from transmission cooler hoses
and install transaxle oil cooler line service splice kit.
Refer to instructions included with kit.
(31) Install transaxle dipstick tube and attach
electrical harness clip.
(32) Connect the A/C lines to compressor.
(33) Connect the A/C compressor electrical connec-
tor.
(34) Evacuate and recharge A/C system.
(35) Connect crankshaft and camshaft position
sensors.
(36) Connect the fuel injector electrical harness
connector and engage clip to support bracket.
(37) Connect engine coolant temperature (ECT)
sensor and ignition coil electrical connectors.
(38) Connect the ground strap to rear of cylinder
head.
(39) Install power steering reservoir.
(40) Engage wire harness clip to engine right side
mount.
(41) Connect the brake booster and speed control
vacuum hoses.
(42) Connect the vacuum hoses to the throttle
body.
(43) Connect the EGR transducer electrical connec-
tor (if equipped).
(44) Connect the TPS, IAC, and MAP sensor elec-
trical connectors.
(45) Connect throttle cables to throttle body.
(46) Install the radiator fans (Refer to 7 - COOL-
ING/ENGINE/RADIATOR FAN - INSTALLATION).
Fig. 13 Right Mount to Engine
1 - BOLT
2 - MOUNT BRACKET
3 - ENGINE RIGHT MOUNT ASSEMBLY
Fig. 14 LEFT MOUNT TO FRAME BRACKET
1 - FRAME BRACKET
2 - FRAME RAIL - LEFT
3 - BOLT
4 - TRANSAXLE MOUNT
9 - 90 ENGINE 3.3/3.8LRS
ENGINE 3.3/3.8L (Continued)
ProCarManuals.com

AIR CLEANER HOUSING
REMOVAL
(1) Disconnect the negative battery cable.
(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
RSENGINE 3.3/3.8L9-99
ProCarManuals.com