engine CHRYSLER VOYAGER 2002 Service Manual
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ENGINE 3.3/3.8L
TABLE OF CONTENTS
page page
ENGINE 3.3/3.8L
DESCRIPTION.........................76
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - INTRODUCTION...........77
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - PERFORMANCE...........78
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - MECHANICAL.............80
DIAGNOSIS AND TESTING - ENGINE OIL
LEAK INSPECTION....................82
DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE TEST........83
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE
TEST...............................83
STANDARD PROCEDURE
STANDARD PROCEDURE - MEASURING
BEARING CLEARANCE USING
PLASTIGAGE........................84
STANDARD PROCEDURE - FORM-IN-
PLACE GASKETS AND SEALERS.........84
STANDARD PROCEDURE - ENGINE
GASKET SURFACE PREPARATION........85
STANDARD PROCEDURE - HYDROSTATIC
LOCKED ENGINE.....................86
STANDARD PROCEDURE - REPAIR OF
DAMAGED OR WORN THREADS.........86
STANDARD PROCEDURE - ENGINE CORE
AND OIL GALLERY PLUGS..............86
REMOVAL - ENGINE ASSEMBLY...........87
INSTALLATION - ENGINE ASSEMBLY........90
SPECIFICATIONS
3.3/3.8L ENGINE......................92
SPECIFICATIONS - TORQUE............95
SPECIAL TOOLS
3.3/3.8L ENGINE......................96
AIR CLEANER ELEMENT
REMOVAL.............................99
INSTALLATION.........................99
AIR CLEANER HOUSING
REMOVAL.............................99
INSTALLATION........................100
CYLINDER HEAD
DESCRIPTION........................100
OPERATION..........................100
DIAGNOSIS AND TESTINGÐCYLINDER HEAD
GASKET...........................100
REMOVAL - CYLINDER HEAD............100
CLEANING...........................101INSPECTION.........................101
INSTALLATION - CYLINDER HEAD.........102
CYLINDER HEAD COVER(S)
DESCRIPTION........................103
CYLINDER HEAD COVER - RIGHT
REMOVAL............................103
INSTALLATION........................103
CYLINDER HEAD COVER - LEFT
REMOVAL............................105
INSTALLATION........................105
INTAKE/EXHAUST VALVES & SEATS
DESCRIPTION........................105
OPERATION..........................105
STANDARD PROCEDURE - REFACING
VALVESANDVALVESEATS ............105
REMOVAL............................106
CLEANING...........................106
INSPECTION.........................106
INSTALLATION........................107
VALVE SPRINGS
DESCRIPTION........................107
OPERATION..........................107
REMOVAL
REMOVAL - CYLINDER HEAD OFF.......108
REMOVAL - CYLINDER HEAD ON........108
INSPECTION.........................109
INSTALLATION
INSTALLATION - CYLINDER HEAD OFF . . . 109
INSTALLATION - CYLINDER HEAD ON....109
ROCKER ARMS
DESCRIPTION
DESCRIPTION - ROCKER ARMS.........110
DESCRIPTION - PUSHRODS............110
OPERATION
OPERATION - ROCKER ARMS..........110
OPERATION - PUSHRODS.............110
REMOVAL - ROCKER ARMS AND SHAFT....110
DISASSEMBLY - ROCKER ARMS AND
SHAFT.............................110
ASSEMBLY - ROCKER ARMS AND SHAFT . . . 111
INSTALLATION - ROCKER ARMS AND
SHAFT.............................111
VALVE STEM SEALS
DESCRIPTION........................112
REMOVAL............................113
INSTALLATION........................113
ENGINE BLOCK
DESCRIPTION........................113
STANDARD PROCEDURE - CYLINDER BORE
HONING............................113
9 - 74 ENGINE 3.3/3.8LRS
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CLEANING...........................113
INSPECTION..........................113
CAMSHAFT & BEARINGS (IN BLOCK)
DESCRIPTION........................114
OPERATION..........................114
REMOVAL............................114
INSPECTION..........................115
INSTALLATION........................115
CONNECTING ROD BEARINGS
STANDARD PROCEDURE - MEASURING
CONNECTING ROD BEARING
CLEARANCE........................115
CRANKSHAFT
DESCRIPTION
DESCRIPTION - 3.3L..................116
DESCRIPTION - 3.8L..................117
OPERATION..........................117
STANDARD PROCEDURE - MEASURING
CRANKSHAFT END PLAY..............117
REMOVAL............................117
INSPECTION..........................118
INSTALLATION........................118
CRANKSHAFT MAIN BEARINGS
STANDARD PROCEDURE - MAIN BEARING
FITTING............................119
REMOVAL - CRANKSHAFT MAIN
BEARINGS..........................121
INSTALLATION - CRANKSHAFT MAIN
BEARINGS..........................121
CRANKSHAFT OIL SEAL - FRONT
REMOVAL............................122
INSTALLATION........................123
CRANKSHAFT OIL SEAL - REAR
REMOVAL............................123
INSTALLATION........................123
CRANKSHAFT REAR OIL SEAL RETAINER
REMOVAL............................124
INSTALLATION........................124
FLEX PLATE
REMOVAL............................124
INSTALLATION........................124
HYDRAULIC LIFTERS (CAM IN BLOCK)
DESCRIPTION........................125
DIAGNOSIS AND TESTING - HYDRAULIC
LIFTERS...........................125
REMOVAL............................126
INSTALLATION........................126
PISTON & CONNECTING ROD
DESCRIPTION........................126
OPERATION..........................126
STANDARD PROCEDURE
STANDARD PROCEDURE - FITTING
CONNECTING RODS..................127
STANDARD PROCEDURE - FITTING
PISTONS...........................127
REMOVAL............................127
INSTALLATION........................128PISTON RINGS
STANDARD PROCEDURE - PISTON RING
FITTING............................130
REMOVAL............................131
INSTALLATION........................131
VIBRATION DAMPER
REMOVAL............................132
INSTALLATION........................132
ENGINE MOUNTING
DESCRIPTION........................133
FRONT MOUNT
REMOVAL............................133
INSTALLATION........................133
LEFT MOUNT
REMOVAL............................134
INSTALLATION........................134
REAR MOUNT
REMOVAL............................135
INSTALLATION........................136
RIGHT MOUNT
REMOVAL............................137
INSTALLATION........................137
LUBRICATION
DESCRIPTION........................137
OPERATION..........................137
DIAGNOSIS AND TESTING - ENGINE OIL
PRESSURE.........................137
OIL
STANDARD PROCEDURE
STANDARD PROCEDURE - ENGINE OIL
AND FILTER CHANGE.................138
STANDARD PROCEDURE - ENGINE OIL
LEVEL CHECK.......................139
OIL COOLER & LINES
DESCRIPTION........................140
OPERATION..........................140
REMOVAL............................140
INSTALLATION........................140
OIL FILTER
REMOVAL............................140
INSTALLATION........................140
OIL FILTER ADAPTER
REMOVAL............................141
INSTALLATION........................141
OIL PAN
REMOVAL............................141
CLEANING...........................141
INSPECTION.........................142
INSTALLATION........................142
OIL PRESSURE RELIEF VALVE
REMOVAL............................142
INSTALLATION........................143
OIL PRESSURE SWITCH
DESCRIPTION........................143
OPERATION..........................143
REMOVAL............................143
INSTALLATION........................143
RSENGINE 3.3/3.8L9-75
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OIL PUMP
DESCRIPTION........................143
REMOVAL............................143
DISASSEMBLY........................144
CLEANING...........................144
INSPECTION.........................144
ASSEMBLY...........................146
INSTALLATION........................146
INTAKE MANIFOLD
DESCRIPTION........................146
OPERATION..........................146
DIAGNOSIS AND TESTING - INTAKE
MANIFOLD LEAKS....................146
INTAKE MANIFOLD - UPPER
STANDARD PROCEDURE
STANDARD PROCEDURE - MANIFOLD
STRIPPED THREAD REPAIR............146
STANDARD PROCEDURE - INTAKE
MANIFOLD VACUUM PORT REPAIR......147
REMOVAL - UPPER INTAKE MANIFOLD.....147
CLEANING...........................148
INSPECTION.........................149
INSTALLATION - UPPER INTAKE
MANIFOLD..........................149
INTAKE MANIFOLD - LOWER
REMOVAL - LOWER INTAKE MANIFOLD....150
CLEANING...........................150
INSPECTION.........................150
INSTALLATION - LOWER INTAKE MANIFOLD . 150
EXHAUST MANIFOLD
DESCRIPTION........................152OPERATION..........................152
EXHAUST MANIFOLD - RIGHT
REMOVAL............................152
CLEANING...........................152
INSPECTION.........................153
INSTALLATION........................153
EXHAUST MANIFOLD - LEFT
REMOVAL............................154
CLEANING...........................154
INSPECTION.........................154
INSTALLATION........................154
VALVE TIMING
STANDARD PROCEDURE
STANDARD PROCEDURE - VALVE TIMING
VERIFICATION.......................155
STANDARD PROCEDURE - MEASURING
TIMING CHAIN WEAR.................155
TIMING CHAIN COVER
REMOVAL............................155
INSTALLATION........................156
TIMING CHAIN AND SPROCKETS
REMOVAL
REMOVAL - TIMING CHAIN AND
CAMSHAFT SPROCKET...............159
REMOVAL - CRANKSHAFT SPROCKET . . . 159
INSTALLATION
INSTALLATION - CRANKSHAFT
SPROCKET.........................159
INSTALLATION - TIMING CHAIN AND
CAMSHAFT SPROCKET...............159
ENGINE 3.3/3.8L
DESCRIPTION
The 3.3 Liter (201 cu. in.) and 3.8 Liter (231 cu.
in.) engines are 60É V-6 engines with cast iron cylin-
der blocks and aluminum cylinder heads (Fig. 1). The
engine uses a single, block mounted camshaft with
pushrods to actuate the valves. These engines do not
have provisions for a free wheeling valve train.The firing order is 1±2±3±4±5±6. The cylinders are
numbered from the front of the engine to the rear.
The front cylinder bank is numbered 2, 4, and 6. The
rear cylinder bank is numbered 1, 3, and 5.
The engine identification number is located on the
rear of the cylinder block just below the cylinder
head (Fig. 2).
9 - 76 ENGINE 3.3/3.8LRS
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DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - INTRODUCTION
Engine diagnosis is helpful in determining the
causes of malfunctions not detected and remedied by
routine maintenance.
These malfunctions may be classified as either
mechanical (e.g., a strange noise), or performance
(e.g., engine idles rough and stalls).
Refer to the Engine Mechanical and the Engine
Performance diagnostic charts, for possible causes
and corrections of malfunctions (Refer to 9 - ENGINE
- DIAGNOSIS AND TESTING - MECHANICAL)
(Refer to 9 - ENGINE - DIAGNOSIS AND TESTING
- PERFORMANCE).
For fuel system diagnosis, (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY - DIAGNOSIS AND
TESTING).
Additional tests and diagnostic procedures may be
necessary for specific engine malfunctions that can-
not be isolated with the Service Diagnosis charts.
Information concerning additional tests and diagno-
sis is provided within the following:
²Cylinder Compression Pressure Test
²Cylinder Combustion Pressure Leakage Test
²Engine Cylinder Head Gasket Failure Diagnosis
²Intake Manifold Leakage Diagnosis
²Hydraulic Lash Adjuster Noise Diagnosis
²Engine Oil Leak Inspection
Fig. 1 3.3/3.8L V-6 Engines
Fig. 2 Engine Identification
RSENGINE 3.3/3.8L9-77
ENGINE 3.3/3.8L (Continued)
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DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - PERFORMANCE
CONDITION POSSIBLE CAUSE CORRECTION
ENGINE WILL NOT START 1. Weak battery. 1. Test battery. Charge or replace
as necessary. (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM -
DIAGNOSIS AND TESTING)
2. Corroded or loose battery
connections.2. Clean and tighten battery
connections. Apply a coat of light
mineral grease to terminals.
3. Faulty starter. 3. Test starting system. (Refer to 8 -
ELECTRICAL/STARTING -
DIAGNOSIS AND TESTING)
4. Faulty coil(s) or control unit. 4. Test and replace as needed.
(Refer to Appropriate Diagnostic
Information)
5. Incorrect spark plug gap. 5. Set gap. (Refer to 8 -
ELECTRICAL/IGNITION CONTROL
- SPECIFICATIONS)
6. Contamination in fuel system. 6. Clean system and replace fuel
filter.
7. Faulty fuel pump. 7. Test fuel pump and replace as
needed. (Refer to Appropriate
Diagnostic Information)
8. Incorrect engine timing. 8. Check for a skipped timing
belt/chain.
ENGINE STALLS OR IDLES
ROUGH1. Idle speed too low. 1. Test minimum air flow. (Refer to
Appropriate Diagnostic Information)
2. Incorrect fuel mixture. 2. (Refer to Appropriate Diagnostic
Information)
3. Intake manifold leakage. 3. Inspect intake manifold, manifold
gasket, and vacuum hoses.
4. Faulty ignition coil(s). 4. Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)
9 - 78 ENGINE 3.3/3.8LRS
ENGINE 3.3/3.8L (Continued)
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CONDITION POSSIBLE CAUSE CORRECTION
ENGINE LOSS OF POWER 1. Dirty or incorrectly gapped plugs. 1. Clean plugs and set gap.
2. Contamination in fuel system. 2. Clean system and replace fuel
filter.
3. Faulty fuel pump. 3. Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)
4. Incorrect valve timing. 4. Correct valve timing.
5. Leaking cylinder head gasket. 5. Replace cylinder head gasket.
6. Low compression. 6. Test compression of each
cylinder.
7. Burned, warped, or pitted valves. 7. Replace valves.
8. Plugged or restricted exhaust
system.8. Perform exhaust restriction test.
(Refer to 11 - EXHAUST SYSTEM -
DIAGNOSIS AND TESTING) Install
new parts, as necessary.
9. Faulty ignition coil(s). 9. Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)
ENGINE MISSES ON
ACCELERATION1. Dirty or incorrectly gapped spark
plugs.1. Clean spark plugs and set gap.
2. Contamination in Fuel System. 2. Clean fuel system and replace
fuel filter.
3. Burned, warped, or pitted valves. 3. Replace valves.
4. Faulty ignition coil(s). 4. Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)
ENGINE MISSES AT HIGH SPEED 1. Dirty or incorrect spark plug gap. 1. Clean spark plugs and set gap.
2. Faulty ignition coil(s). 2. Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)
3. Dirty fuel injector(s). 3. Test and replace as necessary.
(Refer to Appropriate Diagnostic
Information)
4. Contamination in fuel system. 4. Clean system and replace fuel
filter.
RSENGINE 3.3/3.8L9-79
ENGINE 3.3/3.8L (Continued)
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DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - MECHANICAL
CONDITION POSSIBLE CAUSES CORRECTION
NOISY VALVES 1. High or low oil level in
crankcase.1. Check and correct engine oil
level.
2. Thin or diluted oil. 2. Change oil to correct viscosity.
3. Thick oil 3. (a) Change engine oil and filter.
(b) Run engine to operating
temperature.
(c) Change engine oil and filter
again.
4. Low oil pressure. 4. Check and correct engine oil
pressure problem.
5. Dirt in hydraulic lifters/lash
adjusters.5. Replace hydraulic lifters/lash
adjusters.
6. Worn rocker arms. 6. Inspect oil supply to rocker arms.
7. Worn hydraulic lifters/lash
adjusters.7. Replace hydraulic lifters/lash
adjusters.
8. Worn valve guides. 8. Replace cylinder head assembly.
9. Excessive runout of valve seats
on valve faces.9. Grind valve seats and valves.
CONNECTING ROD NOISE 1. Insufficient oil supply. 1. Check engine oil level.
2. Low oil pressure. 2. Check engine oil level. Inspect oil
pump relief valve and spring.
3. Thin or diluted oil. 3. Change oil to correct viscosity.
4. Thick oil 4. (a) Change engine oil and filter.
(b) Run engine to operating
temperature.
(c) Change engine oil and filter
again.
5. Excessive bearing clearance. 5. Measure bearings for correct
clearance. Repair as necessary.
6. Connecting rod journal
out-of-round.6. Replace crankshaft or grind
surface.
7. Misaligned connecting rods. 7. Replace bent connecting rods.
9 - 80 ENGINE 3.3/3.8LRS
ENGINE 3.3/3.8L (Continued)
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CONDITION POSSIBLE CAUSES CORRECTION
MAIN BEARING NOISE 1. Insufficient oil supply. 1. Check engine oil level.
2. Low oil pressure. 2. Check engine oil level. Inspect oil
pump relief valve and spring.
3. Thin or diluted oil. 3. Change oil to correct viscosity.
4. Thick oil 4. (a) Change engine oil and filter.
(b) Run engine to operating
temperature.
(c) Change engine oil and filter
again.
5. Excessive bearing clearance. 5. Measure bearings for correct
clearance. Repair as necessary.
6. Excessive end play. 6. Check thrust bearing for wear on
flanges.
7. Crankshaft journal out-of-round
or worn.7. Replace crankshaft or grind
journals.
8. Loose flywheel or torque
converter.8. Tighten to correct torque.
OIL PRESSURE DROP 1. Low oil level. 1. Check engine oil level.
2. Faulty oil pressure sensor/switch. 2. Replace oil pressure sensor/
switch.
3. Low oil pressure. 3. Check oil pressure sensor/switch
and main bearing oil clearance.
4. Clogged oil filter. 4. Install new oil filter.
5. Worn parts in oil pump. 5. Replace worn parts or pump.
6. Thin or diluted oil. 6. Change oil to correct viscosity.
7. Oil pump relief valve stuck. 7. Remove valve and inspect, clean,
or replace.
8. Oil pump suction tube loose. 8. Remove oil pan and install new
tube or clean, if necessary.
9. Oil pump cover warped or
cracked.9. Install new oil pump.
10. Excessive bearing clearance. 10. Measure bearings for correct
clearance.
OIL LEAKS 1. Misaligned or deteriorated
gaskets.1. Replace gasket(s).
2. Loose fastener, broken or porous
metal part.2. Tighten, repair or replace the
part.
3. Misaligned or deteriorated cup or
threaded plug.3. Replace as necessary.
RSENGINE 3.3/3.8L9-81
ENGINE 3.3/3.8L (Continued)
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CONDITION POSSIBLE CAUSES CORRECTION
OIL CONSUMPTION OR SPARK
PLUGS FOULED1. PCV system malfunction. 1. Check system and repair as
necessary. (Refer to 25 -
EMISSIONS CONTROL/
EVAPORATIVE EMISSIONS/PCV
VALVE - DIAGNOSIS AND
TESTING)
2. Worn, scuffed or broken rings. 2. Hone cylinder bores. Install new
rings.
3. Carbon in oil ring slots. 3. Install new rings.
4. Rings fitted too tightly in grooves. 4. Remove rings and check
grooves. If groove is not proper
width, replace piston.
5. Worn valve guide(s). 5. Replace cylinder head assembly.
6. Valve stem seal(s) worn or
damaged.6. Replace seal(s).
DIAGNOSIS AND TESTING - ENGINE OIL LEAK
INSPECTION
Begin with a thorough visual inspection of the
engine, particularly at the area of the suspected leak.
If an oil leak source is not readily identifiable, the
following steps should be followed:
(1) Do not clean or degrease the engine at this
time because some solvents may cause rubber to
swell, temporarily stopping the leak.
(2) Add an oil soluble dye (use as recommended by
manufacturer). Start the engine and let idle for
approximately 15 minutes. Check the oil dipstick to
make sure the dye is thoroughly mixed as indicated
with a bright yellow color under a black light.
(3) Using a black light, inspect the entire engine
for fluorescent dye, particularly at the suspected area
of oil leak. If the oil leak is found and identified,
repair as necessary.
(4) If dye is not observed, drive the vehicle at var-
ious speeds for approximately 24 km (15 miles), and
repeat inspection.
(5)If the oil leak source is not positively
identified at this time, proceed with the air leak
detection test method as follows:
²Disconnect the fresh air hose (make-up air) at
the cylinder head cover and plug or cap the nipple on
the cover.
²Remove the PCV valve hose from the cylinder
head cover. Cap or plug the PCV valve nipple on the
cover.
²Attach an air hose with pressure gauge and reg-
ulator to the dipstick tube.
CAUTION: Do not subject the engine assembly to
more than 20.6 kpa (3 PSI) of test pressure.²Gradually apply air pressure from 1 psi to 2.5
psi maximum while applying soapy water at the sus-
pected source. Adjust the regulator to the suitable
test pressure that provides the best bubbles which
will pinpoint the leak source. If the oil leak is
detected and identified, repair per service manual
procedures.
²If the leakage occurs at the crankshaft rear oil
seal area, refer to the section, Inspection for Rear
Seal Area Leak.
(6) If no leaks are detected, turn off the air supply.
Remove the air hose, all plugs, and caps. Install the
PCV valve and fresh air hose (make-up air). Proceed
to next step.
(7) Clean the oil off the suspect oil leak area using
a suitable solvent. Drive the vehicle at various
speeds approximately 24 km (15 miles). Inspect the
engine for signs of an oil leak by using a black light.
NOTE: If oil leakage is observed at the dipstick tube
to block location; remove the tube, clean and reseal
using MoparTStud & Bearing Mount (press fit tube
applications only), and for O-ring style tubes,
remove tube and replace the O-ring seal.
INSPECTION FOR REAR SEAL AREA LEAKS
Since it is sometimes difficult to determine the
source of an oil leak in the rear seal area of the
engine, a more involved inspection is necessary. The
following steps should be followed to help pinpoint
the source of the leak.
If the leakage occurs at the crankshaft rear oil seal
area:
(1) Disconnect the battery.
(2) Raise the vehicle.
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ENGINE 3.3/3.8L (Continued)
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(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)
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