Silver Valve Guide Sleeve Tool C6818
Dial Indicator Tool C3339
Crankshaft Pulley/Damper Installer Tool C3688
Crankshaft Sprocket Puller Tool 6444
Crankshaft Sprocket Puller Jaws Tool 6820
Crankshaft Sprocket Installer Tool 3718
Crankshaft Sprocket Installer Tool MD990799
Front Oil Seal Installer Tool 6806
Front Oil Seal Installer Tool 6761
Camshaft Bearing Installer Tool C3132A
9 - 368 ENGINE 8.0LDR
ENGINE 8.0L (Continued)
Compression Ring Installer Tool C4184
Piston Ring Compressor Tool C385
Seal Installer Tool 6687
Crankshaft Main Bearing Remover/Installer Tool
C3059
Puller 1026
Crankshaft Damper Removal Insert 8513
Pressure Tester Kit 7700
Bloc±Chek±Kit C-3685±A
DRENGINE 8.0L 9 - 369
ENGINE 8.0L (Continued)
AIR CLEANER ELEMENT
REMOVAL
Filter Element Only
Housing removal is not necessary for element (fil-
ter) replacement.
(1) Loosen clamp (Fig. 4) and disconnect air duct
at air cleaner cover.
(2) Pry over 4 spring clips (Fig. 4) from housing
cover (spring clips retain cover to housing).
(3) Release housing cover from locating tabs on
housing (Fig. 4) and remove cover.
(4) Remove air cleaner element (filter) from hous-
ing.
(5) Clean inside of housing before replacing ele-
ment.
Housing Assembly
(1) Loosen clamp (Fig. 4) and disconnect air duct
at air cleaner cover.
(2) Lift entire housing assembly from 4 locating
pins (Fig. 5).
INSTALLATION
(1) Install filter element into housing.
(2) Position housing cover into housing locating
tabs (Fig. 4).(3) Pry up 4 spring clips (Fig. 4) and lock cover to
housing.
(4) Install air duct to air cleaner cover and tighten
hose clamp to 3 N´m (30 in. lbs.) torque.
(5) If any other hose clamps were removed from
air intake system, tighten them to 3.4 N´m (30 in.
lbs.) torque.
(6) If any bolts were removed from air resonator
housing or air intake tubing, tighten them to 4.5 N´m
(40 in. lbs.) torque.
CYLINDER HEAD
DESCRIPTION
The alloy cast iron cylinder heads (Fig. 6) are held
in place by 12 bolts. The spark plugs are located in
the peak of the wedge between the valves.
DIAGNOSIS AND TESTINGÐCYLINDER HEAD
GASKET FAILURE
A cylinder head gasket leak can be located between
adjacent cylinders or between a cylinder and the
adjacent water jacket.
²Possible indications of the cylinder head gasket
leaking between adjacent cylinders are:
þ Loss of engine power
þ Engine misfiring
þ Poor fuel economy
Fig. 4 AIR CLEANER HOUSING COVER
1 - CLAMP
2 - AIR DUCT
3 - AIR CLEANER COVER
4 - LOCATING TABS
5 - CLIPS (4)
Fig. 5 AIR CLEANER HOUSING
1 - AIR CLEANER HOUSING ASSEMBLY
2 - LOCATING PINS (4)
9 - 370 ENGINE 8.0LDR
²Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
þ Engine overheating
þ Loss of coolant
þ Excessive steam (white smoke) emitting from
exhaust
þ Coolant 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 in this
section. An engine cylinder head gasket leaking
between adjacent cylinders will result in approxi-
mately 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.
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
(1) Disconnect the negative cable from the battery.
(2) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(3) Remove the heat shields (Fig. 7).
(4) Remove the intake manifold-to-generator
bracket support rod. Remove the generator (Refer to
8 - ELECTRICAL/CHARGING/GENERATOR -
REMOVAL).
(5) Remove closed crankcase ventilation system.
(6) Disconnect the evaporation control system.
(7) Remove the air cleaner.
(8) Perform the Fuel System Pressure release pro-
cedure (Refer to 14 - FUEL SYSTEM/FUEL DELIV-
ERY - STANDARD PROCEDURE). Disconnect the
Fig. 6 Cylinder Head Assembly
1 - SPARK PLUG
2 - INTAKE VALVES
3 - SPARK PLUG
4 - INTAKE VALVES
5 - SPARK PLUG
6 - SPARK PLUG
7 - INTAKE VALVE
8 - SPARK PLUG
9 - EXHAUST VALVE
10 - EXHAUST VALVES
11 - EXHAUST VALVES
Fig. 7 Spark Plug Wire Heat Shields (Left Side
Shown)
1 - EXHAUST MANIFOLD
2 - HEAT SHIELD
DRENGINE 8.0L 9 - 371
CYLINDER HEAD (Continued)
fuel line (Refer to 14 - FUEL SYSTEM/FUEL DELIV-
ERY/QUICK CONNECT FITTING - STANDARD
PROCEDURE).
(9) Disconnect accelerator linkage and if so
equipped, the speed control and transmission kick-
down cables.
(10) Remove coil pack and bracket (Fig. 8).
(11) Disconnect the coil wires.
(12) Disconnect heat indicator sending unit wire.
(13) Disconnect heater hoses and bypass hose.
(14) Remove upper intake manifold and throttle
body as an assembly (Refer to 9 - ENGINE/MANI-
FOLDS/INTAKE MANIFOLD - REMOVAL).
(15) Remove cylinder head covers and gaskets
(Refer to 9 - ENGINE/CYLINDER HEAD/CYLIN-
DER HEAD COVER(S) - REMOVAL).
(16) Remove the EGR tube. Discard the gasket, for
right side only.
(17) Remove lower intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL). Discard the flange side gaskets and the
front and rear cross-over gaskets.
(18) Disconnect exhaust pipe from exhaust mani-
fold.
(19) Remove exhaust manifolds and gaskets (Refer
to 9 - ENGINE/MANIFOLDS/EXHAUST MANIFOLD
- REMOVAL).
(20) Remove rocker arm assemblies and push rods
(Refer to 9 - ENGINE/CYLINDER HEAD/ROCKER
ARM / ADJUSTER ASSY - REMOVAL). Identify to
ensure installation in original locations.(21) Remove the head bolts from each cylinder
head and remove cylinder heads. Discard the cylin-
der head gasket.
(22) Remove spark plugs.
CLEANING
Clean all surfaces of cylinder block and cylinder
heads. Be sure material does not fall into the lifters
and surrounding valley.
Clean cylinder block front and rear gasket surfaces
using a suitable solvent.
Clean the exhaust manifold to cylinder head mat-
ing areas.
INSPECTION
Inspect all surfaces with a straightedge if there is
any reason to suspect leakage. The out-of-flatness
specifications are 0.0007 mm/mm (0.0004 inch/inch),
0.127 mm/152 mm (0.005 inch/6 inches) any direction
or 0.254 mm (0.010 inch) overall across head. If
exceeded, either replace head or lightly machine the
head surface.
The cylinder head surface finish should be
1.78-4.57 microns (15-80 microinches).
Inspect push rods. Replace worn or bent rods.
Inspect rocker arms. Replace if worn or scored.
INSTALLATION
(1) Position the new cylinder head gaskets onto
the cylinder block.
(2) Position the cylinder heads onto head gaskets
and cylinder block.
(3) Tighten the cylinder head bolts in two steps
(Fig. 9):
²Step 1ÐTighten all cylinder head bolts, in
sequence, to 58 N´m (43 ft. lbs.) torque.
²Step 2ÐTighten all cylinder head bolts, in
sequence, to 143 N´m (105 ft. lbs.) torque.
²
CAUTION: When tightening the rocker arm bolts,
make sure the piston in that cylinder is NOT at
TDC. Contact between the valves and piston could
occur.
Fig. 8 Coil Pack and Bracket
1 - COIL PACKS AND BRACKET
2 - MOUNTING BOLTS (4)
Fig. 9 Cylinder Head Bolt Tightening Sequence
9 - 372 ENGINE 8.0LDR
CYLINDER HEAD (Continued)
(4) Install push rods and rocker arm assemblies in
their original position (Refer to 9 - ENGINE/CYLIN-
DER HEAD/ROCKER ARM / ADJUSTER ASSY -
INSTALLATION).
(5) Install lower intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSTALLATION).
(6) Install the upper intake manifold onto the
lower intake manifold (Refer to 9 - ENGINE/MANI-
FOLDS/INTAKE MANIFOLD - INSTALLATION).
(7) Install the exhaust manifolds and new gaskets
(Refer to 9 - ENGINE/MANIFOLDS/EXHAUST
MANIFOLD - INSTALLATION).
(8) Install exhaust pipe to the exhaust manifold.
Tighten the bolts to 34 n´m (25 ft. lbs.) torque.
(9) Using a new gasket, position the EGR tube to
the intake manifold and the exhaust manifold.
Tighten the EGR tube nut to 34 N´m (25 ft. lbs.)
torque. Tighten the bolts to 20 N´m (174 in. lbs.)
torque.
(10) Install the heat shields and the washers.
Make sure that heat shields tabs hook over the
exhaust gasket.Tighten the nuts to 15 N´m (132 in.
lbs.) torque.
(11) Adjust and Install the spark plugs (Refer to 8
- ELECTRICAL/IGNITION CONTROL/SPARK
PLUG - INSTALLATION).
(12) Install coil packs and bracket. Tighten the
bracket bolts to 21 N´m (190 in. lbs.) torque. Connect
the coil wires.
(13) Connect heat indicator sending unit wire.
(14) Connect the heater hoses and bypass hose.
(15) Connect the accelerator linkage and if so
equipped, the speed control and transmission kick-
down cables.
(16) Install the fuel line (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/QUICK CONNECT FIT-
TING - STANDARD PROCEDURE).
(17) Install the generator (Refer to 8 - ELECTRI-
CAL/CHARGING/GENERATOR - INSTALLATION)
and drive belt (Refer to 7 - COOLING/ACCESSORY
DRIVE/DRIVE BELTS - INSTALLATION).
(18) Install the intake manifold-to-generator
bracket support rod. Tighten the bolts to 41 N´m (30
ft. lbs.) torque.
(19) The cylinder head cover gasket can be used
again. Install the gasket onto the head rail.For the
left side the number tab is at the front of
engine with the number up. For the right side
the number tab is at the rear of engine with the
number up.
CAUTION: The cylinder head cover fasteners have a
special plating. DO NOT use alternative fasteners.(20) Install cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(21) Install closed crankcase ventilation system.
(22) Connect the evaporation control system.
(23) Install the air cleaner.
(24) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(25) Connect the negative cable to the battery.
(26) Check for leaks (fuel, oil, antifreeze, etc.).
CYLINDER HEAD COVER(S)
DESCRIPTION
Die-cast magnesium cylinder head covers (Fig. 10)
reduce noise and provide a good sealing surface. A
steel backed silicon gasket is used with the cylinder
head cover. This gasket can be used again.
REMOVAL
Die-cast magnesium cylinder head covers (Fig. 12)
reduce noise and provide a good sealing surface. A
steel backed silicon gasket is used with the cylinder
head cover (Fig. 11).
(1) Disconnect the negative cable from the battery.
(2) Disconnect closed ventilation system and evap-
oration control system from cylinder head cover.
Identify each system for installation.
(3) Remove the upper intake manifold to remove
the right side head cover (Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - REMOVAL).
Fig. 10 Cylinder Head Cover
1 - CYLINDER HEAD COVER
DRENGINE 8.0L 9 - 373
CYLINDER HEAD (Continued)
(4) Remove cylinder head cover bolts and stud
bolts. Remove the covers and gaskets (Fig. 11). The
gasket may be used again.
CLEANING
Clean cylinder head cover gasket surface.
Clean head rail, if necessary.
INSPECTION
Inspect cover for distortion and straighten, if nec-
essary.
Check the gasket for use in head cover installation.
If damaged, use a new gasket.
INSTALLATION
(1) Check the gasket for use in head cover instal-
lation. If damaged, use a new gasket.
(2) Install the gasket onto the head rail.For the
left side the number tab is at the front of
engine with the number up. For the right side
the number tab is at the rear of engine with the
number up.
CAUTION: The cylinder head cover fasteners have a
special plating. DO NOT use alternative fasteners.
(3) Position the cylinder head cover onto the gas-
ket. Install the stud bolts and hex head bolts in theproper positions (Fig. 12). Tighten the stud bolts and
the bolts to 16 N´m (144 in. lbs.) torque.
(4) If removed, install the upper intake manifold
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - INSTALLATION).
(5) Install closed crankcase ventilation system and
evaporation control system onto the proper head
cover. DO NOT switch the systems.
(6) Connect the negative cable to the battery.
(7) Start engine and check for leaks.
Fig. 11 Cylinder Head Cover Gaskets
1 - CYLINDER HEAD COVER GASKETS
2 - TAB WITH NUMBER UP
Fig. 12 Cylinder Head Covers
1 - CYLINDER HEAD COVER
2 - CYLINDER HEAD COVER GASKET
9 - 374 ENGINE 8.0LDR
CYLINDER HEAD COVER(S) (Continued)
INTAKE/EXHAUST VALVES &
SEATS
DESCRIPTION
The valves (Fig. 13) are arranged in-line and
inclined 18É. The rocker pivot support and the valve
guides are cast integral with the heads.
STANDARD PROCEDURE
VALVE SERVICE
VALVE GUIDES
Measure valve stem guide clearance as follows:
(1) Install Black Valve Guide Sleeve Tool C-6819
over valve stem for theINTAKEvalve and install
valve (Fig. 14). The special sleeve places the valve at
the correct height for checking with a dial indicator.
(2) Install Silver Valve Guide Sleeve Tool C-6818
over valve stem for theEXHAUSTvalve and install
valve. The special sleeve places the valve at the cor-
rect height for checking with a dial indicator.
(3) Attach Dial Indicator Tool C-3339 to cylinder
head and set it at right angle of valve stem being
measured (Fig. 15).
(4) Move valve to and from the indicator. The total
dial indicator reading should not exceed 0.432 mm
(0.017 inch). Ream the guides for valves with over-
size stems if dial indicator reading is excessive or if
the stems are scuffed or scored.
Service valves with oversize stems are available as
shown below
REAMER SIZE CHART
REAMER O/S VALVE GUIDE SIZE
0.076 mm 8.026 - 8.052 mm
(0.003 in.) (0.316 - 0.317 in.)
0.381 mm 8.331 - 8.357 mm
(0.015 in.) (0.316 - 0.329 in.)
(5) Slowly turn reamer by hand and clean guide
thoroughly before installing new valve.Ream the
valve guides from standard to 0.381 mm (0.015
inch). Use a 2 step procedure so the valve
guides are reamed true in relation to the valve
seat:
²Step 1ÐReam to 0.0763 mm (0.003 inch).
²Step 2ÐReam to 0.381 mm (0.015 inch).
Fig. 13 Intake and Exhaust ValvesÐ8.0L Engine
1 - MARGIN
2 - VALVE SPRING RETAINER LOCK GROOVE
3 - STEM
4-FACE
Fig. 14 Positioning Valve Spacer Tool (Typical)
1 - VALVE
2 - SPACER TOOL
Fig. 15 Measuring Valve Guide Wear
1 - VALVE
2 - SPECIAL TOOL C-3339
DRENGINE 8.0L 9 - 375