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-
outside
surface of each O/S
tappet bore.
Milled pad adjacent to two tapped holes 3/89
on each end of cylinder head.ValveCompressorAdaptingStudTool6715
ValveSpringCompressorAdapterTool6716A
ValveSpringCompressorToolMD-998772A
ValveSpringCompressorScrewTool6756
BlackValveGuideSleeveToolC6819
ENGINE 8.0L
9 - 368
ENGINE 8.0L (Continued)DR
SilverValveGuideSleeveToolC6818
CrankshaftSprocketInstallerTool3718
DialIndicatorToolC3339
CrankshaftSprocketInstallerToolMD990799
CrankshaftPulley/DamperInstallerToolC3688
FrontOilSealInstallerTool6806
CrankshaftSprocketPullerTool6444
FrontOilSealInstallerTool6761
CrankshaftSprocketPullerJawsTool6820
CamshaftBearingInstallerToolC3132A
DR ENGINE 8.0L (Continued)
ENGINE 8.0L
9 - 369
CrankshaftDamperRemovalInsert8513
PressureTesterKit7700
Bloc–Chek–KitC-3685–A
CompressionRingInstallerToolC4184
PistonRingCompressorToolC385
SealInstallerTool6687
CrankshaftMainBearingRemover/InstallerTool
C3059
Puller1026
9 - 370
ENGINE 8.0L
DR
AIR CLEANER ELEMENT REMOVAL
Filter Element Only
Housing removal is not necessary for element (fil-
ter) replacement.
at air cleaner cover.
(1) Loosen clamp (Fig. 4) and disconnect air duct
(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-
(5) Clean inside of housing before replacing ele-
ing.
ment.
Fig.5AIRCLEANERHOUSING
1 - AIR CLEANER HOUSING ASSEMBLY 2 - LOCATING PINS (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 TESTING—CYLINDER HEAD GASKET FAILURE
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:
− Loss of engine power − Engine misfiring − Poor fuel economy
Fig.4AIRCLEANERHOUSINGCOVER
1 - CLAMP 2 - AIR DUCT 3 - AIR CLEANER COVER 4 - LOCATING TABS 5 - CLIPS (4)
Housing Assembly
(1) Loosen clamp (Fig. 4) and disconnect air duct
at air cleaner cover.
pins (Fig. 5).
(2) Lift entire housing assembly from 4 locating
INSTALLATION
(1) Install filter element into housing. (2) Position housing cover into housing locating
tabs (Fig. 4).
ENGINE 8.0L
9 - 371
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).
DR CYLINDER HEAD (Continued)
Fig.6CylinderHeadAssembly
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
† Possible indications of the cylinder head gasket leaking between a cylinder and an adjacent water jacket are:
− Engine overheating − Loss of coolant − Excessive steam (white smoke) emitting from
exhaust
− 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.
Fig.7SparkPlugWireHeatShields(LeftSide
Shown)
1 - EXHAUST MANIFOLD 2 - HEAT SHIELD
the
(4) Remove
intake manifold-to-generator bracket support rod. Remove the generator (Refer to - 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
ENGINE 8.0L
9 - 372
CYLINDER HEAD (Continued)fuel line (Refer to 14 - FUEL SYSTEM/FUEL DELIV- ERY/QUICK CONNECT FITTING - STANDARD PROCEDURE).
(9) Disconnect accelerator
so equipped, the speed control and transmission kick- down cables.
linkage and if
(10) Remove coil pack and bracket (Fig. 8).
Fig.8CoilPackandBracket
1 - COIL PACKS AND BRACKET 2 - MOUNTING BOLTS (4)
(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 REMOVAL). Discard the flange side gaskets and the front and rear cross-over gaskets.
MANIFOLD
(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.
DR
(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.
and cylinder block.
(2) Position the cylinder heads onto head gaskets
(Fig. 9):
(3) Tighten the cylinder head bolts in two steps † Step 1—Tighten all cylinder head bolts, † Step 2—Tighten all cylinder head bolts, †
sequence, to 143 N·m (105 ft. lbs.) torque.
sequence, to 58 N·m (43 ft. lbs.) torque.
in
in
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.9CylinderHeadBoltTighteningSequence
DR CYLINDER HEAD (Continued)
ENGINE 8.0L
9 - 373
(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 -
MANIFOLD
ENGINE/MANIFOLDS/INTAKE 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 to 9 - ENGINE/MANIFOLDS/EXHAUST
(Refer 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
CONTROL/SPARKELECTRICAL/IGNITION
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
intake manifold-to-generator bracket support rod. Tighten the bolts to 41 N·m (30
ft. lbs.) torque.the
(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.
Fig.10CylinderHeadCover
1 - CYLINDER HEAD COVER
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).
ENGINE 8.0L
9 - 374
CYLINDER HEAD COVER(S) (Continued)(4) Remove cylinder head cover bolts and stud bolts. Remove the covers and gaskets (Fig. 11). The gasket may be used again.
DR
proper positions (Fig. 12). Tighten the stud bolts and the bolts to 16 N·m (144 in. lbs.) torque.
Fig.11CylinderHeadCoverGaskets
1 - CYLINDER HEAD COVER GASKETS 2 - TAB WITH NUMBER UP
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 the
Fig.12CylinderHeadCovers
1 - CYLINDER HEAD COVER 2 - CYLINDER HEAD COVER GASKET
(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.
DR
ENGINE 8.0L
9 - 375
INTAKE/EXHAUST VALVES & SEATS DESCRIPTION
The valves (Fig. 13) are arranged in-line and inclined 18°. The rocker pivot support and the valve guides are cast integral with the heads.
Fig.14PositioningValveSpacerTool(Typical)
1 - VALVE 2 - SPACER TOOL
Fig.13IntakeandExhaustValves—8.0LEngine
1 - MARGIN 2 - VALVE SPRING RETAINER LOCK GROOVE 3 - STEM 4 - FACE
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 the INTAKE valve 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 the EXHAUST valve 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
Fig.15MeasuringValveGuideWear
1 - VALVE 2 - SPECIAL TOOL C-3339
REAMER SIZE CHART
REAMER O/S
VALVE GUIDE SIZE
0.076 mm (0.003 in.) 0.381 mm (0.015 in.)
8.026 - 8.052 mm (0.316 - 0.317 in.) 8.331 - 8.357 mm (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:† Step 1—Ream to 0.0763 mm (0.003 inch). † Step 2—Ream to 0.381 mm (0.015 inch).ENGINE 8.0L
9 - 376
INTAKE/EXHAUST VALVES & SEATS (Continued) REFACING VALVES AND VALVE SEATSThe intake and exhaust valves have a 45° face
angle and a 45° to 44 1/2° seat angle (Fig. 16).
DR
Fig.16ValveFaceandSeatAngles
1 - CONTACT POINT
VALVE FACE AND SEAT ANGLES CHART
ITEM
DESCRIPTION SPECIFICATION SEAT WIDTH
1.016 - 1.524
mm
INTAKE
(0.040 - 0.060
in.)
SEAT WIDTH
1.016 - 1.524
mm
EXHAUST
(0.040 - 0.060
FACE ANGLE (INT. and EXT.) SEAT ANGLE (INT. and EXT.)
CONTACT SURFACE
in.)
45°
441⁄2°
—
VALVES
Inspect the remaining margin after the valves are refaced (Fig. 17). Valves with less than 1.190 mm (0.047 inch) margin should be discarded.
VALVE SEATS
(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.
Fig.17IntakeandExhaustValves
1 - MARGIN 2 - VALVE SPRING RETAINER LOCK GROOVE 3 - STEM 4 - FACE
(2) Measure the concentricity of valve seat using a dial indicator. Total runout should not exceed 0.038
mm (0.0015 inch) total indicator reading.(3) Inspect the valve seat with Prussian blue to determine where the valve contacts the seat. To do this, coat valve seat LIGHTLY with 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 the top edge of valve face, lower valve seat with a 15° stone. If the blue is transferred to bottom edge of valve face raise valve seat with a 60° stone. (4) When seat is properly positioned the width of valve seats should be 1.016-1.524 mm (0.040-0.060
inch).VALVE SPRING INSPECTION
Whenever valves have been removed for inspection, reconditioning or replacement, valve springs should be tested. As an example the compression length of the spring to be tested is 1-5/16 inch. Turn table of Universal Valve Spring Tester Tool until surface is in line with the 1-5/16 inch mark on the threaded stud. Be sure the zero mark is to the front (Fig. 18). 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 2. This will give the spring load at test length. Fractional measurements are indicated on the table for finer adjustments. Refer to specifications to obtain specified height and allowable tensions. Discard the springs that do not meet specifications.
DR INTAKE/EXHAUST VALVES & SEATS (Continued)
ENGINE 8.0L
9 - 377
Fig.18TestingValveSpringforCompressed
1 - TORQUE WRENCH 2 - VALVE SPRING TESTER
REMOVAL
REMOVAL—VALVE STEM SEALS
NOTE: This procedure is done with the cylinder head installed.
(1) Disconnect the negative cable from the battery. (2) Set engine basic timing to Top Dead Center
(TDC) and remove air cleaner.
(3) Remove cylinder head covers (Refer to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) - REMOVAL) and spark plugs (Refer to 8
CONTROL/SPARK PLUG - REMOVAL).ELECTRICAL/IGNITION
(4) Using suitable socket and flex handle at crank- shaft retaining bolt, turn engine so that the piston of the cylinder to be worked on, is at TDC on the com- pression stroke.
(5) Remove rocker arms (Refer to 9 - ENGINE/ CYLINDER HEAD/ROCKER ARM / ADJUSTER ASSY - REMOVAL).
(6) With air hose attached to an adapter installed in the spark plug hole, apply 620-689 kPa (90-100
psi) air pressure.Valve
(7) Using
Tool MD-998772A with adapter 6716A (Fig. 19), compress valve spring and remove retainer valve locks and valve spring.
Compressor
Spring
(8) Remove the valve stem seal.
Fig.19ValveSpringCompressorMD-998772Awith
Adaptor6716-AandScrew6765
1 - SPECIAL TOOL MD 998772A 2 - SPECIAL TOOL 6765
3 - SPECIAL TOOL 6716A 4 - AIR HOSEREMOVAL—VALVES AND VALVE SPRINGS
(1) Remove the cylinder head (Refer ENGINE/CYLINDER HEAD - REMOVAL).
to 9 -
(2) Special studs must be used to adapt the Valve Spring Compressor Tool to the V-10 cylinder head (Fig. 20). Install the metric end into the Special Tool MD998772A and the 5/16 end into the cylinder head.
Fig.20SpecialStuds6715forV-10Engine
1 - SPECIAL TOOL 6715
ENGINE 8.0L
9 - 378
INTAKE/EXHAUST VALVES & SEATS (Continued)(3) Compress valve springs using Valve Spring Compressor Tool MD-998772A with Adapter 6716A and Screw 6765 (Fig. 21). Tap the retainer using a brass drift and ball peen hammer to loosen locks away from retainer.
DR
Fig.22PositioningValvewithToolC-3973
1 - VALVE 2 - SPACER TOOL
Fig.23MeasuringValveGuideWear
1 - VALVE 2 - SPECIAL TOOL C-3339
stems if dial indicator reading is excessive or if the stems are scuffed or scored.
INSTALLATION
INSTALLATION—VALVE STEM SEAL (1) Install new seal onto valve stem. (2) Position valve spring onto valve stem. (3) Position Valve Spring Compressor with Adapter
Studs onto cylinder head
(4) Compress valve spring and install retainer
valve locks.
hole.
Studs.
(5) Remove air hose and adapter from spark plug
(6) Remove Valve Spring Compressor and Adapter
(7) Install rocker arms (Refer to 9 - ENGINE/CYL- INDER HEAD/ROCKER ARM / ADJUSTER ASSY - INSTALLATION).
Fig.21ValveSpringCompressorMD-998772Awith
Adaptor6716-AandScrew6765
1 - SPECIAL TOOL MD 998772A 2 - SPECIAL TOOL 6765
3 - SPECIAL TOOL 6716A 4 - AIR HOSE(4) Remove valve retaining locks, valve spring retainers and valve springs. Check for abnormal wear, replace as required.
(5) Remove the valve stem seals. (6) Before removing valves, remove any burrs from valve stem lock grooves to prevent damage to the valve guides. Identify valves to ensure installation in original location.
CLEANING
Clean valves thoroughly. Discard burned, warped,
or cracked valves.
Remove carbon and varnish deposits from inside of
valve guides with a reliable guide cleaner.
INSPECTION
Measure valve stems for wear. If wear exceeds
0.051 mm (0.002 in.), replace the valve.
Measure valve stem guide clearance as follows: (1) Install Valve Guide Sleeve Tool C-3973 over valve stem and install valve (Fig. 22). The special sleeve places the valve at the correct height for checking with a dial indicator.
(2) Attach dial indicator Tool C-3339 to cylinder head and set it at right angles to valve stem being measured (Fig. 23).
(3) Move valve to and from the indicator. The total dial indicator reading should not exceed 0.432 mm (0.017 in.). Ream the guides for valves with oversize
DR INTAKE/EXHAUST VALVES & SEATS (Continued)
ENGINE 8.0L
9 - 379
(8) 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.
(9) Install
cylinder head cover
to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) - INSTALLATION) (Fig. 24).
(Refer
Fig.24CylinderHeadCovers
1 - CYLINDER HEAD COVER 2 - CYLINDER HEAD COVER GASKET
(10) Install closed crankcase ventilation system. (11) Connect the evaporation control system. (12) Install air cleaner. (13) Connect the negative cable to the battery. (14) Road test vehicle and check for leaks.
INSTALLATION—VALVES AND VALVE SPRINGS thoroughly. Discard burned,
(1) Clean valves
warped and cracked valves.
(2) Remove carbon and varnish deposits from inside of valve guides with a reliable guide cleaner. (3) Measure valve stems for wear. If wear exceeds
0.051 mm (0.002 inch), replace the valve.
(4) Make sure there are no burrs on valve stems. (5) Coat valve stems with lubrication oil. Insert
valves into valve guides in cylinder head.
(6) Install new seals on all valve guides (BLACK on intake and BROWN on exhaust). Install valve springs and valve retainers.
(7) Compress valve springs with Valve Spring Compressor Tool MD-998772A and adapter 6716A, install locks and release tool. Tap the retainer with a brass or heavy plastic hammer to ensure locks have been seated.
(8) If valves and/or seats were ground, measure the installed height of springs. Make sure the mea- surement is taken from bottom of spring seat in cyl- inder head to the bottom surface of spring retainer. If spacers are installed, measure from the top of spacer. If height is greater than 42.86 mm (1-11/16 inches), install a 1.587 mm (1/16 inch) spacer in head coun- terbore. Ensure this brings spring height back to nor- mal, 41.27 to 42.86 mm (1-5/8 to 1-11/16 inch).
(9) Install the cylinder head (Refer to 9 - ENGINE/
CYLINDER HEAD - INSTALLATION).
ROCKER ARM / ADJUSTER ASSY REMOVAL
(1) Disconnect spark plug wires by pulling the boot
straight out in line with plug.
(2) Remove cylinder head cover and gasket (Refer - ENGINE/CYLINDER HEAD/CYLINDER
to HEAD COVER(S) - REMOVAL).
(3) Remove the rocker arm bolts and the rocker arm assembly (Fig. 25). Place rocker arm assemblies on a bench in the same order as removed.
(4) Remove the push rods and place them on a
bench in the same order as removed.
INSTALLATION
CAUTION: DO NOT rotate or crank the engine dur- ing or immediately after rocker arm installation. Allow the hydraulic roller tappets adequate time to bleed down (about 5 minutes).
ENGINE 8.0L
9 - 380
ROCKER ARM / ADJUSTER ASSY (Continued)DR
CAMSHAFT & BEARINGS (IN BLOCK)
REMOVAL
REMOVAL—CAMSHAFT BEARINGS
This procedure requires that the engine is removed
from the vehicle.
(1) With engine completely disassembled, drive out
rear cam bearing core hole plug.
NOTE: It is not advisable to attempt to replace cam- shaft bearings unless special removal and installa- tion tools are available, such as recommended tool 8544 Camshaft Bushing Remover Installer.
(2) Using recommended tool 8544 Camshaft Bush-
ing Remover Installer, Drive out bearing shells.
REMOVAL—CAMSHAFT
(1) Remove rocker arms and push rods (Refer to 9
- ENGINE/CYLINDER HEAD/ROCKER ARM / ADJUSTER ASSY - REMOVAL). Identify each part so it can be installed in its original location.NOTE: The 4 corner tappets can not be removed without removing the cylinder heads and gaskets. However, they can be lifted and retained for cam- shaft removal.
(2) Remove the Bolts retaining the yoke retaining spider. Remove the yoke retaining spider, tappet aligning yokes and tappets.
(3) Remove upper and lower intake manifolds (Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI- FOLD - REMOVAL).
(4) Remove timing chain cover (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT / CHAIN COVER(S) - REMOVAL) and timing chain and sprockets (Refer to 9 - ENGINE/VALVE TIMING/ TIMING BELT/CHAIN AND SPROCKETS REMOVAL).
Fig.25RockerArm-Typical
1 - ROCKER ARMS 2 - ROCKER ARM PEDESTALS 3 - RETAINER
(1) Install the push rods in the same order as
removed.
(2) Install rocker arm assemblies in the same order as removed. Tighten the rocker arm bolts to 53
N·m (40 ft. lbs.) torque.(3) Install cylinder head cover and gasket (Refer to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) - INSTALLATION).
(4) Connect spark plug wires.
ENGINE BLOCK CLEANING
Clean cylinder block thoroughly and check all core
hole plugs for evidence of leaking.
INSPECTION
Examine block for cracks or fractures. The cylinder walls should be checked for out-of- round and taper with Cylinder Bore Indicator Tool, Special tool 6879 or equivalent. The cylinder block should be bored and honed with new pistons and rings fitted if: † The cylinder bores show more than 0.127 mm † The cylinder bores show a taper of more than † The cylinder walls are badly scuffed or scored. Boring and honing operation should be closely coor- dinated with the fitting of pistons and rings so spec- ified clearances may be maintained.
(0.005 inch) out-of-round.
0.254 mm (0.010 inch).
DR CAMSHAFT & BEARINGS (IN BLOCK) (Continued)
ENGINE 8.0L
9 - 381
(5) Remove camshaft thrust plate (Fig. 26).
(4) Line up key with keyway in sprocket, then using Special Tools C-3688, C-3718 and MB990799
install crankshaft timing sprocket. Make sure the sprocket seats against the crankshaft shoulder (Fig. 27).Fig.26Camshaft
1 - CAMSHAFT 2 - THRUST PLATE
(6) Install a long bolt into front of camshaft to aid in removal of the camshaft. Remove camshaft, being careful not to damage cam bearings with the cam lobes.
INSTALLATION
INSTALLATION—CAMSHAFT BEARINGS
(1) Install new camshaft bearings using recom- mended Tool 8544 Camshaft Bushing Remover Installer, by sliding the new camshaft bearing shell over proper adapter.
(2) Bearings must be carefully aligned to bring oil holes into full register with oil passages from the main bearing. If the camshaft bearing shell oil holes are not in exact alignment, remove and install them correctly. Install a new core hole plug at the rear of camshaft. Be sure this plug does not leak.
INSTALLATION—CAMSHAFT
(1) Lubricate camshaft lobes and camshaft bearing journals. Using a long bolt, insert the camshaft into the cylinder block.
NOTE: Whenever an engine has been rebuilt, a new camshaft and/or new tappets installed, add 1 pint of MoparT Crankcase Conditioner, or equivalent. The oil mixture should be left in engine for a minimum of 805 km (500 miles). Drain at the next normal oil change.
(2) Install camshaft thrust plate. Tighten the torx
bolts to 22 N·m (16 ft. lbs.) torque.
(3) Check camshaft end play. The end play should be 0.051-0.152 mm (0.002-0.006 inch) with a new thrust plate and up to 0.254 mm (0.010 inch) with a used thrust plate. If not within these limits install a new thrust plate.
Fig.27CrankshaftSprocketInstallation
1 - SPECIAL TOOL C-3688
2 - SPECIAL TOOL C-3718
3 - SPECIAL TOOL MD990799(5) Install timing chain and sprocket (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT/CHAIN AND SPROCKETS - INSTALLATION).
(6) Install the timing chain cover (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT / CHAIN COVER(S) - INSTALLATION).
(7) Install the crankshaft pulley/damper (Refer to BLOCK/VIBRATION
ENGINE/ENGINE
DAMPER - INSTALLATION).
(8) Prime oil pump by squirting oil in the oil filter mounting hole and filling the J-trap of the front tim- ing cover. When oil is running out, install oil filter that has been filled with oil.
(9) Each tappet reused must be installed in the same position from which it was removed. When camshaft is replaced, all of the tappets must be replaced.
(10) Install tappets and push rods in their original
location.
retaing spider.
(11) Position the tappet aligning yokes and yoke
(12) Install the retaining spider mounting bolts.
Tighten bolts to 22 N·m (16 ft. lbs.).
ENGINE 8.0L
9 - 382
CAMSHAFT & BEARINGS (IN BLOCK) (Continued)DR
(13) Install the rocker arms (Refer to 9 - ENGINE/ CYLINDER HEAD/ROCKER ARM / ADJUSTER ASSY - INSTALLATION).
(14) 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.
Fig.28CylinderHeadCover
1 - CYLINDER HEAD COVER 2 - CYLINDER HEAD COVER GASKET
CAUTION: The cylinder head cover fasteners have a special plating. DO NOT use alternative fasteners.
(15) Install cylinder head cover (Fig. 28) (Refer to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) - INSTALLATION).
(16) Install the intake manifolds (Refer to 9 -
MANIFOLD
ENGINE/MANIFOLDS/INTAKE INSTALLATION).
(17) Start engine and check for leaks.
CONNECTING ROD BEARINGS STANDARD PROCEDURE - CONNECTING ROD BEARING FITTING
Fit all rods on a bank until completed. DO NOT alternate from one bank to another, because connect- ing rods and pistons are not interchangeable from one bank to another.
The bearing caps are not
should be marked at removal assembly.
interchangeable and to ensure correct
Each bearing cap has a small V-groove across the parting face. When installing the lower bearing shell, be certain that the V-groove in the shell is in line with the V-groove in the cap. This provides lubrica- tion of the cylinder wall in the opposite bank.
The bearing shells must be installed so that the tangs are in the machined grooves in the rods and caps.
Limits of taper or out-of-round on any crankshaft journals should be held to 0.025 mm (0.001 in.). Bearings are available in 0.025 mm (0.001 in.), 0.051
mm (0.002 in.), 0.076 mm (0.003 in.), 0.254 mm (0.010 in.) and 0.305 mm (0.012 in.) undersize. Install the bearings in pairs. DO NOT use a new bearing half with an old bearing half. DO NOT file the rods or bearing caps.CRANKSHAFT REMOVAL
When a crankshaft is replaced, all main and con- necting rod bearings should be replaced with new bearings. Therefore, selective fitting of the bearings is not required when a crankshaft and bearings are replaced.
(1) Remove the oil pan and oil pickup tube (refer
to Oil Pan in this section for correct procedure).
(2) Remove the timing chain cover and gasket. Remove and discard the front crankshaft oil seal and cover gasket.
(3) Remove Transmission (refer
to Group 21,
Transmission).
(4) Remove the rear seal retainer (refer to Crank- shaft Rear Seal Retainer in this section for correct procedure).
(5) Identify main bearing caps before removal (Fig. 29). Remove bearing caps and lower bearings one at a time.
(6) Remove the connecting rod bearing caps. (7) Lift the crankshaft straight out of the block. (8) Remove the upper main bearings from the
block.
DR CRANKSHAFT (Continued)
ENGINE 8.0L
9 - 383
(9) Apply a rearward axial
load of 667 N (150
lbs-f) on crankshaft centerline, driving No.3 main cap and thrust bearing against No.3 bulkhead. Repeat procedure, driving crankshaft forward to align rear flange of thrust bearings in a common plane. Front face of No.1 main cap must not extend forward in front of face of No.1 bulkhead.(10) Install the oil pickup tube. Tighten the bolts
to 16 N·m (144 in. lbs.) torque.
(11) Install the oil pan.
CRANKSHAFT MAIN BEARINGS STANDARD PROCEDURE—FITTING CRANKSHAFT MAIN BEARINGS
Bearing caps are not interchangeable and should be marked at removal to ensure correct assembly. Upper and lower bearing halves are NOT inter- changeable. All lower main bearing halves are inter- changeable. Upper main bearing halves of No. 2, 4, and 5 are interchangeable. Upper main bearing halves of No. 1 and 6 are interchangeable, this also applies to the lower bearing halves.
The No.3 main bearing is flanged to carry the crankshaft thrust loads. This bearing is NOT inter- changeable with any other bearing halves in the engine. Bearing shells are available in standard and the following undersizes: 0.25 mm (0.001 inch), 0.051
mm (0.002 inch), 0.076 mm (0.003 inch), 0.254 mm (0.010 inch) and 0.305 mm (0.012 inch). Never install an undersize bearing that will reduce clearance below specifications.REMOVAL
(1) Remove the oil pan and oil pump pick-up tube (Refer to 9 - ENGINE/LUBRICATION/OIL PAN - REMOVAL).
(2) Identify bearing caps before removal. Remove
bearing caps one at a time.
(3) Remove upper half of bearing by inserting Crankshaft Main Bearing Remover/Installer Tool C-3059 into the oil hole of crankshaft (Fig. 30).
(4) Slowly rotate crankshaft clockwise, forcing out
upper half of bearing shell.
INSTALLATION
Only one main bearing should be selectively fitted while all other main bearing caps are properly tight- ened. All bearing capbolts removed during service procedures are to be cleaned and oiled before instal- lation.
When installing a new upper bearing shell, slightly
chamfer the sharp edges from the plain side.
Fig.29MainBearingIdentification
1 - MAIN BEARING CAP 2 - UPPER MAIN BEARINGS 3 - CRANKSHAFT 4 - LOWER MAIN BEARINGS
INSTALLATION
When a crankshaft is replaced, all main and con- necting rod bearings should be replaced with new bearings. Therefore, selective fitting of the bearings is not required when a crankshaft and bearings are replaced.
NOTE: Lubricate crankshaft main bearings with clean engine oil.
(1) Position upper main bearings into block. (2) Position the crankshaft into the cylinder block. (3) Lubricate the main journals with clean engine oil. Install upper main bearings, caps and bolts. Fol- low the 2 step tightening sequence, starting with main bearing cap 1.
(4) Lubricate the connecting rod bearings and jour- nals with clean engine oil. Carefully install connect- ing rods to the crankshaft.
(5) Using Special Tool 8359 Seal Installer install
new oil into oil seal retainer.
(6) Using Special Tool 6687 Guide, install the rear
seal retainer with a new gasket.
(7) Install the timing chain cover with a new gas-
ket and oil seal.
(8) Prime oil pump by squirt oil in the oil filter mounting hole and filling the J-trap of the front tim- ing cover. When oil is running out, install oil filter that has been filled with oil.
ENGINE 8.0L
9 - 384
CRANKSHAFT MAIN BEARINGS (Continued)DR
(3) Place a suitable tool behind the lips of the oil seal to pry the oil seal outward. Be careful not to damage the crankshaft seal surface of the cover (Fig. 31).
Fig.30UpperMainBearingRemovaland
InstallationwithToolC-3059
1 - SPECIAL TOOL C-3059
2 - BEARING 3 - SPECIAL TOOL C-3059
4 - BEARING(1) Start bearing in place, and insert Crankshaft Main Bearing Remover/Installer Tool C-3059 into oil hole of crankshaft (Fig. 30).
(2) Slowly rotate crankshaft counterclockwise slid-
ing the bearing into position. Remove Tool C-3059.
(3) Lubricate the main journals with clean engine oil. Install main bearing caps and bolts. Follow the 2
step tightening sequence, starting with No. 1 main bearing cap.(4) Apply a rearward axial
load of 667 N (150
lbs-f) on crankshaft centerline, driving No.3 main cap and thrust bearing against No.3 bulkhead. Repeat procedure, driving crankshaft forward to align rear flange of thrust bearings in a common plane. Front face of No.1 main cap must not extend forward in front of face of No.1 bulkhead.(5) Install the oil pump pick-up tube and oil pan (Refer to 9 - ENGINE/LUBRICATION/OIL PAN - INSTALLATION).
CRANKSHAFT OIL SEAL - FRONT
REMOVAL
REMOVAL—FRONT OIL SEAL - FRONT COVER INSTALLED
(1) Disconnect the negative cable from the battery. (2) Remove vibration damper from the crankshaft (Refer to 9 - ENGINE/ENGINE BLOCK/VIBRATION DAMPER - REMOVAL).
Fig.31TimingChainCoverandOilSeal
1 - TIMING CHAIN COVER 2 - OIL SEAL
REMOVAL—FRONT OIL SEAL - FRONT COVER REMOVED
(1) Remove engine front
to 9 - ENGINE/VALVE TIMING/TIMING BELT / CHAIN COVER(S) - REMOVAL).
(Refer
cover
(2) Place a suitable tool behind the lips of the oil seal to pry the oil seal outward. Be careful not to damage the crankshaft seal surface of the cover.
INSTALLATION
INSTALLATION—FRONT OIL SEAL – FRONT COVER INSTALLED
(1) Position the crankshaft front oil seal onto seal installer special tool 6806 and C-3688 (Fig. 32). Install seal.
(2) Install vibration damper (Refer to 9 - ENGINE/ ENGINE BLOCK/VIBRATION DAMPER - INSTAL- LATION).
(3) Install serpentine belt (Refer to 7 - COOLING/ ACCESSORY DRIVE/DRIVE BELTS - INSTALLA- TION).
(4) Install cooling fan and shroud (Refer to 7 - COOLING/ENGINE/RADIATOR FAN - INSTALLA- TION).
(5) Connect negative cable to the battery. (6) Start engine and check for leaks.
INSTALLATION—FRONT OIL SEAL - FRONT COVER REMOVED
(1) Position the crankshaft front oil seal onto seal
installer special tool 6806.
DR CRANKSHAFT OIL SEAL - FRONT (Continued)
ENGINE 8.0L
9 - 385
Fig.32TimingChainCoverandOilSeal
1 - SPECIAL TOOL C-3688
2 - SPECIAL TOOL 6806(2) Use tool 6761 to support timing chain cover when installing oil seal with tool 6806 (Fig. 33), install seal (Fig. 34).
Fig.33OilSeal,Tools—6806and6761
1 - FRONT COVER 2 - SPECIAL TOOL 6761
3 - FRONT OIL SEAL 4 - SPECIAL TOOL 6806Fig.34OilSealInstalled
1 - SPECIAL TOOL 6806
2 - SPECIAL TOOL 6761(3) Install engine front
to 9 - ENGINE/VALVE TIMING/TIMING BELT / CHAIN COVER(S) - INSTALLATION).
(Refer
cover
CRANKSHAFT OIL SEAL - REAR REMOVAL
NOTE: This procedure does not require the removal of the seal retainer from the engine block.
(1) Remove the transmission. (2) Carefully,
remove the rear
retainer. Discard the oil seal.
seal
from the
INSTALLATION
(1) Wash all parts in a suitable solvent and inspect
carefully for damage or wear.
(2) Position Special Tool 6687 Seal Guide, onto the
crankshaft.
(3) Position the oil seal onto the Seal guide, then using Special Tool 8359 Seal Installer and C–4171
Driver Handle, Install the oil seal.(4) The seal face surface must be countersunk into
the retainer .762–1.27mm (0.030–0.050 in.).
(5) Install the transmission. (6) Check and verify engine oil is at correct level. (7) Start engine and check for leaks.
9 - 386
ENGINE 8.0L
DR
CRANKSHAFT REAR OIL SEAL RETAINER REMOVAL
(1) Disconnect negative cable from battery. (2) Remove the transmission. (3) Remove the drive plate / flywheel. (4) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(5) Remove the rear oil seal retainer mounting
(6) Carefully remove the retainer from the engine
bolts.
block.
INSTALLATION
engine block.
from the retainer.
(1) Throughly clean all gasket resdue from the
(2) Use extream care and clean all gasket resdue
(3) Apply a small amount of Mopart Silicone Rub- ber Adhesive Sealant to the retainer gasket. Position the gasket onto the retainer.
(4) Position Special Tool 6687 Seal Guide onto the
crankshaft.
(5) Position the retainer and seal over the guide
and onto the engine block.
(6) Install the retainer mounting bolts. Tighten the
bolts to 22 N·m (16 ft. lbs.).
(7) Install the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - INSTALLATION).
(8) Install the drive plate / flywheel. (9) Install the transmission. (10) Check and verify engine oil level. (11) Start engine and check for leaks.
HYDRAULIC LIFTERS DIAGNOSIS AND TESTING—HYDRAULIC TAPPETS
Before disassembling any part of the engine to cor- rect tappet noise, check the oil pressure. If vehicle has no oil pressure gauge, install a reliable gauge at the pressure sending-unit. The pressure should be between 207-552 kPa (30-80 psi) at 3,000 RPM.
level, check dipstick. The oil
Check the oil level after the engine reaches normal operating temperature. Allow 5 minutes to stabilize oil in the pan should never be above the FULL mark or below the ADD OIL mark on dipstick. Either of these two con- ditions could be responsible for noisy tappets.
level
OIL LEVEL
HIGH
If oil level is above the FULL mark, it is possible for the connecting rods to dip into the oil. With the engine running, this condition could create foam in the oil pan. Foam in oil pan would be fed to the hydraulic tappets by the oil pump causing them to lose length and allow valves to seat noisily.
LOW
Low oil level may allow oil pump to take in air. When air is fed to the tappets, they lose length, which allows valves to seat noisily. Any leaks on intake side of oil pump through which air can be drawn will create the same tappet action. Check the lubrication system from the intake strainer to the pump cover, including the relief valve retainer cap. When tappet noise is due to aeration, it may be intermittent or constant, and usually more than one tappet will be noisy. When oil level and leaks have been corrected, operate the engine at fast idle. Run engine for a sufficient time to allow all of the air inside the tappets to be bled out.
TAPPET NOISE DIAGNOSIS
(1) To determine source of tappet noise, operate
engine at idle with cylinder head covers removed.
(2) Feel each valve spring or rocker arm to detect noisy tappet. The noisy tappet will cause the affected spring and/or rocker arm to vibrate or feel rough in operation.
NOTE: Worn valve guides or cocked springs are sometimes mistaken for noisy tappets. If such is the case, noise may be dampened by applying side thrust on the valve spring. If noise is not apprecia- bly reduced, it can be assumed the noise is in the tappet. Inspect the rocker arm push rod sockets and push rod ends for wear.
(3) Valve tappet noise ranges from light noise to a heavy click. A light noise is usually caused by exces- sive leak-down around the unit plunger, or by the plunger partially sticking in the tappet body cylinder. The tappet should be replaced. A heavy click is caused by a tappet check valve not seating, or by for- eign particles wedged between the plunger and the tappet body. This will cause the plunger to stick in the down position. This heavy click will be accompa- nied by excessive clearance between the valve stem and rocker arm as valve closes. In either case, tappet assembly should be removed for inspection and clean- ing.
DR HYDRAULIC LIFTERS (Continued)
(4) The valve train generates a noise very much like a light tappet noise during normal operation. Care must be taken to ensure that tappets are mak- ing the noise. If more than one tappet seems to be noisy, it’s probably not the tappets.
LEAK-DOWN TEST
ENGINE 8.0L
9 - 387
After cleaning and inspection, test each tappet for specified leak-down rate tolerance to ensure zero-lash operation (Fig. 35).
Swing the weighted arm of the hydraulic valve tap- pet tester away from the ram of the Universal Leak- Down Tester.
(1) Place a 7.925-7.950 mm (0.312-0.313 inch) diameter ball bearing on the plunger cap of the tap- pet.
(2) Lift the ram and position the tappet (with the
ball bearing) inside the tester cup.
(3) Lower the ram, then adjust the nose of the ram until it contacts the ball bearing. DO NOT tighten the hex nut on the ram.
(4) Fill the tester cup with hydraulic valve tappet
test oil until the tappet is completely submerged.
(5) Swing the weighted arm onto the push rod and pump the tappet plunger up and down to remove air. When the air bubbles cease, swing the weighted arm away and allow the plunger to rise to the normal position.
(6) Adjust the nose of the ram to align the pointer with the SET mark on the scale of the tester and tighten the hex nut.
(7) Slowly swing the weighted arm onto the push
rod.
(8) Rotate the cup by turning the handle at the base of the tester clockwise one revolution every 2
seconds.(9) Observe the leak-down time interval from the instant the pointer aligns with the START mark on the scale until the pointer aligns with the 0.125
mark. A normally functioning tappet will require 20-110 seconds to leak-down. Discard tappets with leak-down time interval not within this specification.Fig.35Leak-DownTester
1 - POINTER 2 - WEIGHTED ARM 3 - RAM 4 - CUP 5 - HANDLE 6 - PUSH ROD
(6) Cut the cylinder head gasket for accessibility if
the end tappets are to be removed.
(7) Remove yoke retainer spider and tappet align-
ing yokes (Fig. 36).
REMOVAL
(1) Disconnect the negative cable from the battery. (2) Remove the air cleaner. (3) Remove cylinder head cover (Refer to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) - REMOVAL).
(4) Remove rocker arm assembly and push rods (Refer to 9 - ENGINE/CYLINDER HEAD/ROCKER ARM / ADJUSTER ASSY - REMOVAL). Identify push rods to ensure installation in original location. intake manifold (Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI- FOLD - REMOVAL).
(5) Remove upper and lower
Fig.36Tappets,AligningYokeandYokeRetaining
Spider
1 - TAPPET ALIGNING YOLK 2 - YOKE RETAINING SPIDER 3 - TAPPET
DR
PISTON & CONNECTING ROD DESCRIPTION
The pistons (Fig. 37) are elliptically turned so that the diameter at the pin boss is less than its diameter across the thrust face. This allows for expansion under normal operating conditions. Under operating temperatures, expansion forces the pin bosses away from each other, causing the piston to assume a more nearly round shape.
All pistons are machined to the same weight,
regardless of size, to maintain piston balance.
The piston pin rotates in the piston only and is retained by the press interference fit of the piston pin in the connecting rod.
The pistons have a unique dry-film lubricant coat- ing baked onto the skirts to reduce friction. The lubricant is particularly effective during engine break-in, but with time, the material becomes embed- ded into cylinder bore walls and continues to reduce friction.
The pistons are LH and RH bank specific.
ENGINE 8.0L
9 - 388
HYDRAULIC LIFTERS (Continued)(8) Pull tappet out of bore with a twisting motion. If all tappets are to be removed, identify tappets to ensure installation in original location.
(9) If the tappet or bore in cylinder block is scored, scuffed, or shows signs of sticking, ream the bore to next oversize. Replace with oversize tappet.
(10) Check camshaft lobes for abnormal wear.
CLEANING
Clean tappet with a suitable solvent. Rinse in hot water and blow dry with a clean shop rag or com- pressed air.
INSTALLATION
(1) Lubricate tappets. (2) Install
tappets
in their original positions. Ensure that the oil bleed hole (if so equipped) faces forward.
(3) Install tappet aligning yokes. Position the yoke retainer spider over the tappet aligning yokes (Fig. 36)Install the yoke retaining spider bolts and tighten to 22 N·m (16 ft. lbs.) torque.
(4) Install the push rods in their original location. (5) Install the rocker arms (Refer to 9 - ENGINE/ CYLINDER HEAD/ROCKER ARM / ADJUSTER ASSY - INSTALLATION).
(6) Install lower and upper intake manifold (Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANIFOLD - INSTALLATION).
(7) 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. (8) Install
to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) - INSTALLATION).
cylinder head cover
(Refer
(9) Install the air cleaner.
CAUTION: To prevent damage to valve mechanism, engine must not be run above fast idle until all hydraulic tappets have filled with oil and have become quiet.
(10) Connect the negative cable to the battery. (11) Road test vehicle and check for leaks.
Fig.37PistonandConnectingRod—8.0LEngine 1 - FRONT I.D. TOWARDS THIS SIDE 2 - ORIENTATION BUTTON TOWARDS REAR (R.H. ONLY) 2, 4, 6, 8, 10
3 - ORIENTATION BUTTON TOWARDS FRONT (L.H. ONLY) 1, 3, 5, 7, 9DR PISTON & CONNECTING ROD (Continued) STANDARD PROCEDURE—PISTON FITTING
REMOVAL
ENGINE 8.0L
9 - 389
Piston and cylinder wall must be clean and dry. Specified clearance between the piston and the cylin- der wall is 0.013-0.038 mm (0.0005-0.0015 inch). The max. allowable clearance is 0.0762 mm (0.003 in.).
Piston diameter should be measured at the top of skirt, 90° to piston pin axis. Cylinder bores should be measured halfway down the cylinder bore and trans- verse to the engine crankshaft center line.
Pistons and cylinder bores should be measured at
normal room temperature, 21°C (70°F).
(1) To correctly select the proper size piston, a cyl- inder bore gauge, capable of reading in .00019
INCREMENTS is required (Fig. 38). If a bore gauge is not available, do not use an inside micrometer.The coating material is applied to the piston after the final piston machining process. Measuring the out- side diameter of a coated piston will not provide accurate results. Therefore measuring the inside diameter of the cylinder bore with a dial Bore Gauge is MANDATORY. . To correctly select the proper size piston, a cylinder bore gauge capable of reading in .00019 increments is required.Piston installation into the cylinder bore require slightly more pressure than that required for non-coated pistons. The bonded coating on the piston will give the appearance of a line-to-line fit with the cylinder bore.Fig.38BoreGauge
1 - BORE GAUGE 2 - CYLINDER BORE 3 - 2-5/16 in.
(1) Remove the engine from the vehicle (Refer to 9
- ENGINE - REMOVAL).
(2) Remove cylinder head (Refer to 9 - ENGINE/
CYLINDER HEAD - REMOVAL).
(3) Remove the oil pan and oil pump pick-up tube (Refer to 9 - ENGINE/LUBRICATION/OIL PAN - REMOVAL).
(4) Remove top ridge of cylinder bores with a reli- able ridge reamer before removing pistons from cyl- inder block. Be sure to keep tops of pistons covered during this operation.
(5) Be sure the connecting rod and connecting rod cap are identified with the cylinder number. Remove connecting rod cap. Install connecting rod bolt guide set on connecting rod bolts.
(6) Pistons and connecting rods must be removed from top of cylinder block. When removing piston and connecting rod assemblies, rotate crankshaft center the connecting rod in the cylinder bore and at BDC. Be careful not to nick crankshaft journals. DO NOT try to remove black coating on skirt. This is the dry film lubricant.
(7) After removal, install bearing cap on the mat-
ing rod.
CLEANING
Clean the piston and connecting rod assembly
using a suitable solvent.
INSPECTION
Check the connecting rod journal
for excessive wear, taper and scoring (Refer to 9 - ENGINE/EN- GINE BLOCK/CONNECTING ROD BEARINGS - STANDARD PROCEDURE).
Check the connecting rod for signs of twist or bend-
ing.
Check the piston for taper and elliptical shape before it is fitted into the cylinder bore (Refer to 9 - ENGINE/ENGINE BLOCK/PISTON & CONNECT- ING ROD - STANDARD PROCEDURE).
Check the piston for scoring, or scraping marks in the piston skirts. Check the ring lands for cracks and/or deterioration.
INSTALLATION
(1) Check the crankshaft connecting rod journal
for excessive wear, taper and scoring.
(2) Check the cylinder block bore for out-of-round,
taper, scoring and scuffing.
(3) Be sure that compression ring gaps are stag- gered so that neither is in line with oil ring rail gap. (4) Before installing the ring compressor, make sure the oil ring expander ends are butted and the rail gaps located properly (Fig. 39).
ENGINE 8.0L
9 - 390
PISTON & CONNECTING ROD (Continued)NOTE: Be sure position of rings does not change during the following step.
(5) Immerse the piston head and rings in clean engine oil. Slide Piston Ring Compressor Tool C-385
over the piston and tighten with the special wrench (part of Tool C-385).DR
Fig.39ProperRingInstallation
1 - TOP COMPRESSION RING GAP UPPER OIL RING GAP 2 - 2ND COMPRESSION RING GAP LOWER OIL RAIL GAP 3 - SPACER GAP
(6) Install connecting rod bolt protectors on rod bolts, a long protector should be installed on the numbered side of the connecting rod.
(7) Rotate crankshaft so that the connecting rod journal is on the center of the cylinder bore in the bottom dead center (BDC) position. Be sure connect- ing rod and cylinder bore number are the same. Insert rod and piston into cylinder bore. Be sure the piston and rod assemblies are installed in the proper orientation (Fig. 40).
(8) The notch, groove or arrow on top of piston must be pointing toward front of engine. The larger chamfer of the connecting rod bore must be installed toward crankshaft journal fillet.
(9) While tapping the piston down in cylinder bore with the handle of a hammer, guide the connecting rod over the crankshaft journal.
(10) Install rod caps. Install nuts on cleaned and oiled rod bolts and tighten nuts to 61 N·m (45 ft. lbs.) torque.
(11) Install the oil pump pick-up tube and oil pan (Refer to 9 - ENGINE/LUBRICATION/OIL PAN - INSTALLATION).
(12) Install
the cylinder head (Refer
to 9 - ENGINE/CYLINDER HEAD - INSTALLATION) and cylinder head cover (Refer to 9 - ENGINE/CYLIN- DER HEAD/CYLINDER HEAD COVER(S) INSTALLATION).
Fig.40PistonandRodOrientation
1 - FRONT I.D. TOWARDS THIS SIDE 2 - ORIENTATION BUTTON TOWARDS REAR (R.H. ONLY) 2, 4, 6, 8, 10
3 - ORIENTATION BUTTON TOWARDS FRONT (L.H. ONLY) 1, 3, 5, 7, 9(13) Install intake manifold (Refer to 9 - ENGINE/ INSTALLA-
MANIFOLDS/INTAKE MANIFOLD - TION).
(14) Install the engine into the vehicle (Refer to 9 -
ENGINE - INSTALLATION).
PISTON RINGS STANDARD PROCEDURE—FITTING PISTON RINGS
(1) Measurement of end gaps:
(a) Measure piston ring gap 2 inches from bot- tom of cylinder bore. An inverted piston can be used to push the rings down to ensure positioning rings squarely in the cylinder bore before measur- ing.
(b) Insert feeler stock in the gap. Gap for com- pression rings should be between 0.254-0.508 mm (0.010-0.020 inch). The oil ring gap should be 0.381- 1.397 mm (0.015-0.055 inch).
DR PISTON RINGS (Continued)
ENGINE 8.0L
9 - 391
(c) Rings with insufficient end gap may be prop- erly filed to the correct dimension. Ends should be stoned smooth after filing with Arkansas White Stone. Rings with excess gaps should not be used. (2) Install rings and confirm ring side clearance:
(a) Install oil rings being careful not to nick or scratch the piston. Install the oil control rings according to instructions in the package. It is not necessary to use a tool to install the upper and lower rails. Insert oil rail spacer first, then side rails.
(b) Install the second compression rings using Installation Tool C-4184. The compression rings must be installed with the identification mark face up (toward top of piston) and chamfer facing down. An identification mark on the ring is a drill point, a stamped letter O, an oval depression or the word TOP (Fig. 41) (Fig. 43).
(c) Using a ring installer, install the top com- pression ring with the chamfer facing up (Fig. 43). An identification mark on the ring is a drill point, a stamped letter O, an oval depression or the word TOP facing up (Fig. 42).
(d) Measure side clearance between piston ring and ring land. Clearance should be 0.074-0.097 mm (0.0029-0.0038 inch) for the compression rings. The steel rail oil ring should be free in groove, but should not exceed 0.246 mm (0.0097 inch) side clearance.
(e) Pistons with insufficient or excessive side
clearance should be replaced.
Fig.42TopCompressionRingIdentification—Typical 1 - TOP COMPRESSION RING (GRAY IN COLOR) 2 - CHAMFER 3 - ONE DOT
Fig.43CompressionRingChamferLocation—Typical 1 - CHAMFER 2 - TOP COMPRESSION RING 3 - SECOND COMPRESSION RING 4 - PISTON 5 - CHAMFER
Fig.41SecondCompressionRingIdentification—
Typical
1 - SECOND COMPRESSION RING (BLACK CAST IRON) 2 - CHAMFER 3 - TWO DOTS
(3) Arrange ring gaps 180° apart as shown in (Fig.
44).
Fig.44ProperRingInstallation
1 - TOP COMPRESSION RING GAP UPPER OIL RING GAP 2 - 2ND COMPRESSION RING GAP LOWER OIL RAIL GAP 3 - SPACER GAP
9 - 392
ENGINE 8.0L
VIBRATION DAMPER REMOVAL
(1) Disconnect the negative cable from the battery. (2) Remove the following: † Radiator fan (Refer to 7 - COOLING/ENGINE/ RADIATOR FAN - REMOVAL) † Accessory drive belt (Refer to 7 - COOLING/AC- CESSORY DRIVE/DRIVE BELTS - REMOVAL) † Radiator (Refer to 7 - COOLING/ENGINE/RA-
DIATOR - REMOVAL)
(3) Remove crankshaft pulley/damper bolt and
washer from end of crankshaft.
(4) Using Special Tool, 1026 3 Jaw Puller and Spe- cial Tool 8513 Insert, remove pulley—damper from the crankshaft (Fig. 45).
Fig.45CrankshaftPulley—DamperRemoval
1 - 3 JAW PULLER
(5) Inspect crankshaft oil seal.
If damaged or worn, replace the front oil seal (Refer to 9 - ENGINE/ ENGINE BLOCK/CRANKSHAFT OIL SEAL - FRONT - REMOVAL).
INSTALLATION
(1) Position the crankshaft pulley/damper onto the
crankshaft.
(2) Use Special Tool, C-3688 Crankshaft Pulley/ Damper Installer to press the pulley—damper onto the crankshaft. Install crankshaft bolt and washer and tighten to 312 N·m (230 ft. lbs.) torque (Fig. 46). (3) Install the following: † Radiator (Refer to 7 - COOLING/ENGINE/RA-
DIATOR - INSTALLATION)
DR
