ENGINE 8.0L
TABLE OF CONTENTS
page page
ENGINE 8.0L
DESCRIPTION.........................58
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - INTRODUCTION...........58
DIAGNOSIS AND TESTINGÐENGINE
DIAGNOSIS - PERFORMANCE...........59
DIAGNOSIS AND TESTINGÐ ENGINE
DIAGNOSIS - MECHANICAL.............61
DIAGNOSIS AND TESTINGÐENGINE
DIAGNOSIS - LUBRICATION.............63
DIAGNOSIS AND TESTINGÐCYLINDER
COMPRESSION PRESSURE.............64
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE......64
STANDARD PROCEDURE
STANDARD PROCEDUREÐCYLINDER
BORE HONING.......................65
STANDARD PROCEDURE - FORM-IN-
PLACE GASKETS AND SEALERS.........66
STANDARD PROCEDURE - REPAIR
DAMAGED OR WORN THREADS.........66
STANDARD PROCEDUREÐHYDROSTATIC
LOCK...............................66
REMOVAL.............................67
INSTALLATION.........................68
SPECIFICATIONS
8.OL ENGINE........................68
TORQUE............................71
SPECIAL TOOLS
8.0L ENGINE.........................72
AIR CLEANER ELEMENT
REMOVAL - 8.0L........................75
INSTALLATION - 8.0L....................75
CYLINDER HEAD
DESCRIPTION.........................76
DIAGNOSIS AND TESTINGÐCYLINDER HEAD
GASKET FAILURE.....................76
REMOVAL.............................76
CLEANING............................77
INSPECTION..........................77
INSTALLATION.........................77
CYLINDER HEAD COVER(S)
DESCRIPTION.........................78
REMOVAL.............................78
CLEANING............................79
INSPECTION..........................79
INSTALLATION.........................79INTAKE/EXHAUST VALVES & SEATS
DESCRIPTION.........................80
STANDARD PROCEDURE
VALVE SERVICE......................80
REMOVAL
REMOVALÐVALVE STEM SEALS.........82
REMOVALÐVALVES AND VALVE SPRINGS . 82
CLEANING............................83
INSPECTION..........................83
INSTALLATION
INSTALLATIONÐVALVE STEM SEAL......83
INSTALLATIONÐVALVES AND VALVE
SPRINGS............................84
ROCKER ARM / ADJUSTER ASSY
REMOVAL.............................84
INSTALLATION.........................84
ENGINE BLOCK
CLEANING............................85
INSPECTION..........................85
CAMSHAFT & BEARINGS (IN BLOCK)
REMOVAL
REMOVALÐCAMSHAFT BEARINGS.......85
REMOVALÐCAMSHAFT................85
INSTALLATION
INSTALLATIONÐCAMSHAFT BEARINGS . . . 86
INSTALLATIONÐCAMSHAFT............86
CONNECTING ROD BEARINGS
STANDARD PROCEDURE - CONNECTING
ROD BEARING FITTING................87
CRANKSHAFT
REMOVAL.............................87
INSTALLATION.........................88
CRANKSHAFT MAIN BEARINGS
STANDARD PROCEDUREÐFITTING
CRANKSHAFT MAIN BEARINGS..........88
REMOVAL.............................88
INSTALLATION.........................88
CRANKSHAFT OIL SEAL - FRONT
REMOVAL
REMOVALÐFRONT OIL SEAL - FRONT
COVER INSTALLED....................89
REMOVALÐFRONT OIL SEAL - FRONT
COVER REMOVED....................89
INSTALLATION
INSTALLATIONÐFRONT OIL SEAL ± FRONT
COVER INSTALLED....................89
INSTALLATIONÐFRONT OIL SEAL - FRONT
COVER REMOVED....................90
9 - 56 ENGINE 8.0LBR/BE
CRANKSHAFT OIL SEAL - REAR
REMOVAL.............................90
INSTALLATION.........................90
CRANKSHAFT REAR OIL SEAL RETAINER
REMOVAL.............................90
INSTALLATION.........................90
HYDRAULIC LIFTERS
DIAGNOSIS AND TESTINGÐHYDRAULIC
TAPPETS............................91
REMOVAL.............................92
CLEANING............................92
INSTALLATION.........................92
PISTON & CONNECTING ROD
DESCRIPTION.........................93
STANDARD PROCEDUREÐPISTON FITTING . 93
REMOVAL.............................94
CLEANING............................94
INSPECTION..........................94
INSTALLATION.........................94
PISTON RINGS
STANDARD PROCEDUREÐFITTING PISTON
RINGS..............................95
VIBRATION DAMPER
REMOVAL.............................96
INSTALLATION.........................97
FRONT MOUNT
REMOVAL.............................97
INSTALLATION.........................98
REAR MOUNT
REMOVAL.............................98
INSTALLATION.........................98
LUBRICATION
DESCRIPTION.........................98
OPERATION...........................98
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTINGÐENGINE OIL
LEAKS..............................99
DIAGNOSIS AND TESTINGÐENGINE OIL
PRESSURE.........................101OIL
STANDARD PROCEDURE - ENGINE OIL....101
OIL FILTER
REMOVAL............................102
INSTALLATION........................102
OIL PAN
REMOVAL............................102
CLEANING...........................103
INSPECTION.........................103
INSTALLATION........................103
OIL PUMP
REMOVAL............................104
CLEANING...........................104
INSPECTION.........................104
INSTALLATION........................106
INTAKE MANIFOLD
DESCRIPTION........................106
DIAGNOSIS AND TESTINGÐINTAKE
MANIFOLD LEAKAGE.................106
REMOVAL............................107
CLEANING...........................107
INSPECTION.........................108
INSTALLATION........................108
EXHAUST MANIFOLD
DESCRIPTION........................109
OPERATION..........................109
REMOVAL............................109
CLEANING...........................109
INSPECTION.........................109
INSTALLATION........................109
TIMING BELT / CHAIN COVER(S)
REMOVAL............................110
INSTALLATION........................110
TIMING BELT/CHAIN AND SPROCKETS
REMOVAL............................111
INSPECTIONÐMEASURING TIMING CHAIN
STRETCH...........................111
INSTALLATION........................111
BR/BEENGINE 8.0L 9 - 57
ENGINE 8.0L
DESCRIPTION
The 8.0 Liter (488 CID) ten-cylinder engine is a
V-Type lightweight, single cam, overhead valve
engine with hydraulic roller tappets. This engine is
designed for unleaded fuel.
Engine lubrication system consists of a gerotor
type oil pump mounted in the timing chain cover and
driven by the crankshaft. The V-10 uses a full flow
oil filter.
The cylinders are numbered from front to rear; 1,
3, 5, 7, 9 on the left bank and 2, 4, 6, 8, 10 on the
right bank. The firing order is 1-10-9-4-3-6-5-8-7-2
(Fig. 1) .
The engine serial number is located on the lower
left front of the cylinder block in front of the engine
mount (Fig. 2) . When component part replacement is
necessary, use the engine type and serial number for
reference.
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 9 - ENGINE - DIAGNOSIS AND TEST-
ING - Preformance) or (Refer to 9 - ENGINE - DIAG-
NOSIS AND TESTING - Mechanical). Refer to 14 -
FUEL SYSTEM for fuel system diagnosis.
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 (Refer to 9 -
ENGINE - DIAGNOSIS AND TESTING)
²Cylinder Combustion Pressure Leakage Test
(Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
²Cylinder Head Gasket Failure Diagnosis (Refer
to 9 - ENGINE/CYLINDER HEAD - DIAGNOSIS
AND TESTING)
²Intake Manifold Leakage Diagnosis (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
DIAGNOSIS AND TESTING)
²Lash Adjuster (Tappet) Noise Diagnosis (Refer to
9 - ENGINE/ENGINE BLOCK/HYDRAULIC LIFT-
ERS (CAM IN BLOCK) - DIAGNOSIS AND TEST-
ING)
²Engine Oil Leak Inspection (Refer to 9 -
ENGINE/LUBRICATION - DIAGNOSIS AND TEST-
ING)
Fig. 1 Firing Order
Fig. 2 Engine IdentificationÐ(Serial Number)
1 - ENGINE SERIAL NO.
2 - ENGINE MOUNT LOCATION
9 - 58 ENGINE 8.0LBR/BE
CONDITION POSSIBLE CAUSES CORRECTION
7. Blown cylinder head gasket 7. Install new cylinder head gasket
8. Low compression 8. Test cylinder compression (Refer
to 9 - ENGINE - DIAGNOSIS AND
TESTING).
9. Burned, warped, or pitted valves 9. Install/Reface valves as
necessary
10. Plugged or restricted exhaust
system10. Install new parts as necessary
11. Faulty ignition cables 11. Replace any cracked or shorted
cables
12. Faulty ignition coil 12. Test and replace, as necessary
(Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL).
ENGINE STALLS OR ROUGH IDLE 1. Carbon build-up on throttle plate 1. Remove throttle body and
de-carbon. (Refer to 14 - FUEL
SYSTEM/FUEL INJECTION/
THROTTLE BODY - REMOVAL).
2. Engine idle speed too low 2. Check Idle Air Control circuit.
(Refer to 14 - FUEL SYSTEM/FUEL
INJECTION/IDLE AIR CONTROL
MOTOR - DESCRIPTION)
3. Worn or incorrectly gapped spark
plugs3. Replace or clean and re-gap
spark plugs (Refer to 8 -
ELECTRICAL/IGNITION CONTROL/
SPARK PLUG - CLEANING)
4. Worn or burned distributor rotor 4. Install new distributor rotor
5. Spark plug cables defective or
crossed5. Check for correct firing order or
replace spark plug cables. (Refer to
8 - ELECTRICAL/IGNITION
CONTROL/SPARK PLUG CABLE -
DIAGNOSIS AND TESTING)
6. Faulty coil 6. Test and replace, if necessary
(Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL)
7. Intake manifold vacuum leak 7. Inspect intake manifold gasket
and vacuum hoses (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE
MANIFOLD - DIAGNOSIS AND
TESTING).
ENGINE MISSES ON
ACCELERATION1. Worn or incorrectly gapped spark
plugs1. Replace spark plugs or clean and
set gap. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG
- CLEANING)
2. Spark plug cables defective or
crossed2. Replace or rewire secondary
ignition cables. (Refer to 8 -
ELECTRICAL/IGNITION CONTROL/
SPARK PLUG CABLE - REMOVAL)
9 - 60 ENGINE 8.0LBR/BE
ENGINE 8.0L (Continued)
CONDITION POSSIBLE CAUSES CORRECTION
3. Dirt in fuel system 3. Clean fuel system
4. Burned, warped or pitted valves 4. Install new valves
5. Faulty coil 5. Test and replace as necessary
(Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL)
DIAGNOSIS AND TESTINGÐ ENGINE
DIAGNOSIS - MECHANICAL
ENGINE MECHANICAL DIAGNOSIS CHART
CONDITION POSSIBLE CAUSES CORRECTION
NOISY VALVES/LIFTERS 1. High or low oil level in crankcase 1. Check for correct oil level. Adjust
oil level by draining or adding as
needed
2. Thin or diluted oil 2. Change oil. (Refer to 9 -
ENGINE/LUBRICATION/OIL -
STANDARD PROCEDURE)
3. Low oil pressure 3. Check engine oil level. If ok,
Perform oil pressure test. (Refer to
9 - ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING) for
engine oil pressure test/
specifications
4. Dirt in tappets/lash adjusters 4. Clean/replace hydraulic
tappets/lash adjusters
5. Bent push rod(s) 5. Install new push rods
6. Worn rocker arms 6. Inspect oil supply to rocker arms
and replace worn arms as needed
7. Worn tappets/lash adjusters 7. Install new hydraulic tappets/lash
adjusters
8. Worn valve guides 8. Inspect all valve guides and
replace as necessary
9. Excessive runout of valve seats
or valve faces9. Grind valves and seats
CONNECTING ROD NOISE 1. Insufficient oil supply 1. Check engine oil level.
2. Low oil pressure 2. Check engine oil level. If ok,
Perform oil pressure test. (Refer to
9 - ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING) engine
oil pressure test/specifications
3. Thin or diluted oil 3. Change oil to correct viscosity.
(Refer to 9 - ENGINE/
LUBRICATION/OIL - STANDARD
PROCEDURE) for correct
procedure/engine oil specifications
BR/BEENGINE 8.0L 9 - 61
ENGINE 8.0L (Continued)
CONDITION POSSIBLE CAUSES CORRECTION
4. Excessive connecting rod
bearing clearanceMeasure bearings for correct
clearance with plasti-gage. Repair
as necessary
5. Connecting rod journal out of
round5. Replace crankshaft or grind
journals
6. Misaligned connecting rods 6. Replace bent connecting rods
MAIN BEARING NOISE 1. Insufficient oil supply 1. Check engine oil level.
2. Low oil pressure 2. Check engine oil level. If ok,
Perform oil pressure test. (Refer to
9 - ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING)
3. Thin or diluted oil 3. Change oil to correct viscosity.
4. Excessive main bearing
clearance4. Measure bearings for correct
clearance. Repair as necessary
5. Excessive end play 5. Check crankshaft thrust bearing
for excessive wear on flanges
6. Crankshaft main journal out of
round or worn6. Grind journals or replace
crankshaft
7. Loose flywheel or torque
converter7. Inspect crankshaft, flexplate/
flywheel and bolts for damage.
Tighten to correct torque
LOW OIL PRESSURE 1. Low oil level 1. Check oil level and fill if
necessary
2. Faulty oil pressure sending unit 2. Install new sending unit
3. Clogged oil filter 3. Install new oil filter
4. Worn oil pump 4. Replace oil pump assembly.
5. Thin or diluted oil 5. Change oil to correct viscosity.
6. Excessive bearing clearance 6. Measure bearings for correct
clearance
7. Oil pump relief valve stuck 7. Remove valve to inspect, clean
and reinstall
8. Oil pump suction tube loose,
broken, bent or clogged8. Inspect suction tube and clean or
replace if necessary
9. Oil pump cover warped or
cracked9. Install new oil pump
OIL LEAKS 1. Misaligned or deteriorated
gaskets1. Replace gasket
2. Loose fastener, broken or porous
metal part2. Tighten, repair or replace the part
3. Front or rear crankshaft oil seal
leaking3. Replace seal
4. Leaking oil gallery plug or cup
plug4. Remove and reseal threaded
plug. Replace cup style plug
9 - 62 ENGINE 8.0LBR/BE
ENGINE 8.0L (Continued)
CONDITION POSSIBLE CAUSES CORRECTION
EXCESSIVE OIL CONSUMPTION
OR SPARK PLUGS OIL FOULED1. CCV System malfunction 1. (Refer to 25 - EMISSIONS
CONTROL/EVAPORATIVE
EMISSIONS - DESCRIPTION) for
correct operation
2. Defective valve stem seal(s) 2. Repair or replace seal(s)
3. Worn or broken piston rings 3. Hone cylinder bores. Install new
rings
4. Scuffed pistons/cylinder walls 4. Hone cylinder bores and replace
pistons as required
5. Carbon in oil control ring groove 5. Remove rings and de-carbon
piston
6. Worn valve guides 6. Inspect/replace valve guides as
necessary
7. Piston rings fitted too tightly in
grooves7. Remove rings and check ring end
gap and side clearance. Replace if
necessary
DIAGNOSIS AND TESTINGÐENGINE
DIAGNOSIS - LUBRICATION
CONDITION POSSIBLE CAUSES CORRECTION
OIL LEAKS 1. Gaskets and O-Rings. 1.
(a) Misaligned or damaged. (a) Replace as necessary.
(b) Loose fasteners, broken or
porous metal parts.(b) Tighten fasteners, Repair or
replace metal parts.
2. Crankshaft rear seal 2. Replace as necessary.
3. Crankshaft seal flange.
Scratched, nicked or grooved.3. Polish or replace crankshaft.
4. Oil pan flange cracked. 4. Replace oil pan.
5. Timing chain cover seal,
damaged or misaligned.5. Replace seal.
6. Scratched or damaged vibration
damper hub.6. Polish or replace damper.
OIL PRESSURE DROP 1. Low oil level. 1. Check and correct oil level.
2. Faulty oil pressure sending unit. 2. Replace sending unit.
3. Low oil pressure. 3. Check pump and bearing
clearance.
4. Clogged oil filter. 4. Replace oil filter.
5. Worn oil pump. 5. Replace as necessary.
6. Thin or diluted oil. 6. Change oil and filter.
7. Excessive bearing clearance. 7. Replace as necessary.
8. Oil pump relief valve stuck. 8. Clean or replace relief valve.
9. Oil pump suction tube loose or
damaged.9. Replace as necessary.
BR/BEENGINE 8.0L 9 - 63
ENGINE 8.0L (Continued)
CONDITION POSSIBLE CAUSES CORRECTION
OIL PUMPING AT RINGS; SPARK
PLUGS FOULING1. Worn or damaged rings. 1. Hone cylinder bores and replace
rings.
2. Carbon in oil ring slots. 2. Replace rings.
3. Incorrect ring size installed. 3. Replace rings.
4. Worn valve guides. 4. Ream guides and replace valves.
5. Leaking intake gasket. 5. Replace intake gaskets.
6. Leaking valve guide seals. 6. Replace valve guide seals.
DIAGNOSIS AND TESTINGÐCYLINDER
COMPRESSION PRESSURE
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) Clean the spark plug recesses with compressed
air.
(2) Remove the spark plugs (Refer to 8 - ELEC-
TRICAL/IGNITION CONTROL/SPARK PLUG -
REMOVAL).
(3) Secure the throttle in the wide-open position.
(4) Disconnect the ignition coil.
(5) Insert a compression pressure gauge and rotate
the engine with the engine starter motor for three
revolutions.
(6) Record the compression pressure on the third
revolution. Continue the test for the remaining cylin-
ders.
(Refer to 9 - ENGINE - SPECIFICATIONS) for the
correct engine compression pressures.
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE
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
jacket²Any causes for combustion/compression pressure
loss
WARNING: DO NOT REMOVE THE RADIATOR CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE.
SERIOUS BURNS FROM HOT COOLANT CAN
OCCUR.
Check the coolant level and fill as required. DO
NOT install the radiator cap.
Start and operate the engine until it attains nor-
mal operating temperature, then turn OFF the
engine.
Remove the spark plugs.
Remove the oil filler cap.
Remove the air cleaner.
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 and 552 kPa (80 psi) recom-
mended.
Perform the test procedure on each cylinder accord-
ing to the tester manufacturer's instructions. While
testing, listen for pressurized air escaping through
the throttle body, tailpipe or oil filler cap opening.
Check for bubbles in the radiator coolant.
All gauge pressure indications should be equal,
with no more than 25% leakage.
FOR EXAMPLE:At 552 kPa (80 psi) input pres-
sure, a minimum of 414 kPa (60 psi) should be main-
tained in the cylinder CYLINDER COMBUSTION
PRESSURE LEAKAGE DIAGNOSIS CHART.
9 - 64 ENGINE 8.0LBR/BE
ENGINE 8.0L (Continued)