
Downloaded from www.Manualslib.com manuals search engine firing order is 1±8±4±3±6±5±7±2. The engine serial
number is located at the right front side of the
engine block (Fig. 1)
ENGINE LUBRICATION SYSTEM
DESCRIPTION
The lubrication system (Fig. 2) is a full flow filtra-
tion pressure feed type.
OPERATION
Oil from the oil pan is pumped by a gerotor type oil
pump directly mounted to the crankshaft nose. Oil
pressure is controlled by a relief valve mounted
inside the oil pump housing. For lubrication flow
refer to (Fig. 2).
The camshaft exhaust valve lobes and rocker arms
are lubricated through a small hole in the rocker
arm; oil flows through the lash adjuster then through
the rocker arm and onto the camshaft lobe. Due to
the orentation of the rocker arm, the camshaft intake
lobes are not lubed in the same manner as the
exhaust lobes. The intake lobes are lubed through
internal passages in the camshaft. Oil flows through
a bore in the number 3 camshaft bearing bore, and
as the camshaft turns, a hole in the camshaft aligns
with the hole in the camshaft bore allowing engine
oil to enter the camshaft tube. The oil then exits
through 1.6mm (0.063 in.) holes drilled into theintake lobes, lubricating the lobes and the rocker
arms.
ENGINE LUBRICATION FLOW CHARTÐBLOCK: TABLE 1
FROM TO
Oil Pickup Tube Oil Pump
Oil Pump Oil Filter
Oil Filter Block Main Oil Gallery
Block Main Oil Gallery 1. Crankshaft Main Journal
2. Left Cylinder Head*
3. Right Cylinder Head*
Crankshaft Main Journals Crankshaft Rod Journals
Crankshaft Number One Main Journal 1.Front Timing Chain Idler Shaft
2. Both Secondary Chain Tensioners
Left Cylinder Head See Table 2
Right Cylinder Head See Table 2
* The cylinder head
gaskets have an oil restricter to control oil flow to the cylinder heads.
Fig. 1 Engine Identification Location.
1 ± VEHICLE VIN NUMBER LOCATION
2 ± CYLINDER BLOCK RIGHT HAND SIDE
3 ± CYLINDER BORE #2
DN4.7L ENGINE 9 - 3
DESCRIPTION AND OPERATION (Continued)

Downloaded from www.Manualslib.com manuals search engine VALVE SPRING
DESCRIPTION
The valve springs are made from high strength
chrome silicon steel. The springs are common for
intake and exhaust applications. The valve spring
seat is integral with the valve stem seal, which is a
positive type seal to control lubrication.
HYDRAULIC LASH ADJUSTER
DESCRIPTION
Valve lash is controlled by hydraulic lash adjusters
that are stationary mounted in the cylinder heads.
The lash adjusters have a hole in the ball plunger
that feeds oil through the rocker arm squirt holes for
rocker arm roller and camshaft lobe lubrication.
TIMING DRIVE SYSTEM
DESCRIPTION
The timing drive system has been designed to pro-
vide quiet performance and reliability to support a
non-free wheelingengine. Specifically the intake
valves are non-free wheeling and can be easily dam-
aged with forceful engine rotation if camshaft-to-
crankshaft timing is incorrect. The timing drive
system consists of a primary chain and two second-
ary timing chain drives.
OPERATION
The primary timing chain is a single inverted tooth
type. The primary chain drives the large fifty tooth
idler sprocket directly from a 25 tooth crankshaft
sprocket. Primary chain motion is controlled by a
pivoting leaf spring tensioner arm and a fixed guide.
The arm and the guide both use nylon plastic wear
faces for low friction and long wear. The primary
chain receives oil splash lubrication from the second-
ary chain drive and oil pump leakage. The idler
sprocket assembly connects the primary and second-
ary chain drives. The idler sprocket assembly con-
sists of two integral thirty tooth sprockets and a fifty
tooth sprocket that is splined to the assembly. The
spline joint is a non ± serviceable press fit anti rattle
type. A spiral ring is installed on the outboard side of
the fifty tooth sprocket to prevent spline disengage-
ment. The idler sprocket assembly spins on a station-
ary idler shaft. The idler shaft is press-fit into the
cylinder block. A large washer on the idler shaft bolt
and the rear flange of the idler shaft are used to con-
trol sprocket thrust movement. Pressurized oil is
routed through the center of the idler shaft to pro-
vide lubrication for the two bushings used in the
idler sprocket assembly.There are two secondary drive chains, both are
inverted tooth type, one to drive the camshaft in each
SOHC cylinder head. There are no shaft speed
changes in the secondary chain drive system. Each
secondary chain drives a thirty tooth cam sprocket
directly from the thirty tooth sprocket on the idler
sprocket assembly. A fixed chain guide and a hydrau-
lic oil damped tensioner are used to maintain tension
in each secondary chain system. The hydraulic ten-
sioners for the secondary chain systems are fed pres-
surized oil from oil reservoir pockets in the block.
Each tensioner also has a mechanical ratchet system
that limits chain slack if the tensioner piston bleeds
down after engine shut down. The tensioner arms
and guides also utilize nylon wear faces for low fric-
tion and long wear. The secondary timing chains
receive lubrication from a small orifice in the ten-
sioners. This orifice is protected from clogging by a
fine mesh screen which is located on the back of the
hydraulic tensioners.
CAMSHAFT
DESCRIPTION
The camshafts consist of powdered metal steel
lobes which are sinter-bonded to a steel tube. A steel
post or nose piece is friction-welded to the steel cam-
shaft tube. Five bearing journals are machined into
the camshaft, four on the steel tube and one on the
steel nose piece. Camshaft end play is controlled by
two thrust walls that border the nose piece journal.
Engine oil enters the hollow camshafts at the third
journal and lubricates every intake lobe rocker
through a drilled passage in the intake lobe.
ROCKER ARM
DESCRIPTION
The rocker arms are steel stampings with an inte-
gral roller bearing. The rocker arms incorporate a 2.8
mm (0.11 inch) oil hole in the lash adjuster socket for
roller and camshaft lubrication.
CYLINDER HEAD COVER
DESCRIPTION
The cylinder head covers are made of die cast mag-
nesium, and are not interchangeable from side-to-
side. It is imperative that nothing rest on the
cylinder head covers. Prolonged contact with other
items may wear a hole in the cylinder head cover.
9 - 6 4.7L ENGINEDN
DESCRIPTION AND OPERATION (Continued)

Downloaded from www.Manualslib.com manuals search engine SERVICE DIAGNOSISÐPERFORMANCE
CONDITION POSSIBLE CAUSE CORRECTION
ENGINE WILL NOT START 1. Weak battery 1. Charge or replace as necessary.
2. Corroded or loose battery
connections.2. Clean and tighten battery
connections. Apply a coat of light
mineral grease to the terminals.
3. Faulty starter. 3. Refer to Group 8A, Battery/
Starter/ Charging System
Diagnostics.
4. Moisture on ignition wires and
distributor cap.4. Wipe wires and cap clean and
dry.
5. Faulty ignition cables. 5. Replace as necessary.
6. Faulty coil or control unit. 6. Refer to Group 8D, Ignition
System.
7. Incorrect spark plug gap. 7. Refer to Group 8D, Ignition
System.
8. Incorrect ignition timing. 8. Refer to Group 8D, Ignition
System.
9. Dirt or water in fuel system. 9. Clean system and replace fuel
filter.
10. Faulty fuel pump, relay or
wiring.10. Refer to Group 14, Fuel System.
ENGINE STALLS OR ROUGH IDLE 1. Idle speed set to low. 1. Refer to Group 14, Fuel System.
2. Idle mixture to lean or to rich. 2. Refer to Group 14, Fuel System.
3. Vacuum leak. 3. Inspect intake manifold and
vacuum hoses, repair or replace as
necessary.
4. Worn or burned distributor rotor. 4. Replace distributor rotor.
5. Incorrect ignition wiring. 5. Install correct wiring.
6. Faulty coil. 6. Refer to Group 8D, Ignition
System.
7. EGR valve leaking. 7. Refer to Group 25, Emissions
Control System.
8. Incorrect cam timing. 8. Refer to Valve Timing in this
section.
9 - 8 4.7L ENGINEDN
DIAGNOSIS AND TESTING (Continued)

Downloaded from www.Manualslib.com manuals search engine ²Throttle Position (TPS) Switch
²Idle Air Control (IAC) Motor
²Engine Oil Pressure Switch
²Engine Coolant Temperature (ECT) Sensor
²Manifold absolute pressure (MAP) Sensor
²Camshaft Position (CMP) Sensor
²Coil Over Plugs
(31) Disconnect the vacuum lines at the throttle
body and intake manifold.
(32) Release fuel rail pressure then disconnect the
fuel supply quick connect fitting at the fuel rail.
Refer toFUEL SYSTEM for procedure.
(33) Remove power steering pump and position out
of the way.
(34) Install Special Tools 8400 Lifting Studs, into
the cylinder heads.
(35) Install Engine Lifting Fixture Special Tool
8347 (Fig. 47) following these steps.
²Holding the lifting fixture at a slight angle, slide
the large bore in the front plate over the hex portion
of the lifting stud.
²Position the two remaining fixture arms onto
the two Special Tools 8400 Lifting Studs, in the cyl-
inder heads.
²Pull foward and upward on the lifting fixture so
that the lifting stud rest in the slotted area below the
large bore.²Secure the lifting fixture to the three studs
using three 7/16 ± 14 N/C locknuts.
²Make sure the lifting loop in the lifting fixture is
in the last hole (closest to the throttle body) to min-
imize the angle of engine during removal.
(36) Disconnect body ground strap at the right side
cowl (Fig. 48).
(37) Disconnect body ground strap at the left side
cowl (Fig. 49).
NOTE: It will be necessary to support the transmis-
sion in order to remove the engine.
(38) Position a suitable jack under the transmis-
sion.
(39) Remove engine from the vehicle.
INSTALLATION
(1) Position engine in the vehicle.
Position both the left and right side engine mount
brackets and install the through bolts and nuts.
Tighten nuts to4X2 vehicles95 N´m (70 ft. lbs.).
4X4 vehicles102 N´m (75 ft. lbs.).
Fig. 41 Engine Mount Through Bolt and Nut
Removal / InstallationÐ4X4 Vehicles
1 ± ENGINE MOUNT BRACKET (2)
2 ± THROUGH BOLT (2)
3 ± LOCKNUT AND WASHER (2)
4 ± ENGINE ISOLATOR TO ENGINE MOUNT BRACKET STUD (2)
5 ± LOCKNUT (2)
Fig. 42 Axle Isolator Bracket Removal /
InstallationÐ4X4 Vehicles With Automatic
Transmission
1 ± TRANSMISSION
2 ± AXLE ISOLATOR BRACKET
3 ± FRONT AXLE 4X4 VEHICLES
4 ± BOLTS
5 ± ENGINE
9 - 32 4.7L ENGINEDN
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine (2)4X4 vehiclesInstall locknuts onto the engine
mount brackets. Tighten locknuts to 41 N´m (30 ft.
lbs.).
(3) Remove jack from under the transmission.
(4) Remove Engine Lifting Fixture Special Tool
8347 (Fig. 47).
(5) Remove Special Tools 8400 Lifting Studs.
(6) Position generator wiring behind the oil dip-
stick tube, then install the oil dipstick tube upper
mounting bolt.
(7) Connect both left and right side body ground
straps.(8) Install power steering pump.
(9) Connect fuel supply line quick connect fitting.
(10) Connect the vacuum lines at the throttle body
and intake manifold.
(11) Connect engine harness at the following
points (Fig. 46) :
²Intake Air Temperature (IAT) Sensor
²Idle Air Control (IAC) Motor
²Fuel Injectors
²Throttle Position (TPS) Switch
²Engine Oil Pressure Switch
²Engine Coolant Temperature (ECT) Sensor
²Manifold Absolute Pressure (MAP) Sensor
²Camshaft Position (CMP) Sensor
²Coil Over Plugs
(12) Position and install heater hoses and tubes
onto intake manifold.
(13) Install the heater hoses onto the heater core
and the engine front cover.
(14) Install generator.
(15) Install A/C condenser, radiator and transmis-
sion oil cooler as an assembly.
(16) Connect radiator upper and lower hoses.
(17) Connect the transmission oil cooler lines to
the radiator.
(18) Install accessory drive belt, fan assembly and
shroud.
(19) Install A/C compressor. Tighten the A/C com-
pressor and generator M10 mounting bolts 40±68N´M
(30±50 ft. lbs.) and the M8 bolts 22±34 N´m (200±300
in. lbs.).
Fig. 43 Crankshaft Position Sensor
1 ± CRANKSHAFT POSITION SENSOR
2 ± CYLINDER HEAD COVER
3 ± CAMSHAFT POSITION SENSOR
4 ± RIGHT SIDE CYLINDER BLOCK
Fig. 44 Crankcase Breather Connection Points
1 ± CRANKCASE BREATHERS
Fig. 45 Heater Hoses and Tubes Removal /
Installation
1 ± HEATER HOSES AND TUBES
2 ± ROUTING/RETAINING CLIPS
DN4.7L ENGINE 9 - 33
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine INTAKE MANIFOLD
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove resonator assembly and air inlet hose.
(3) Disconnect throttle and speed control cables.
(4) Disconnect electrical connectors for the follow-
ing components: Refer to FUEL SYSTEM for compo-
nent locations.
²Manifold Absolute Pressure (MAP) Sensor
²Intake Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Coolant Temperature (CTS) Sensor
²Idle Air Control (IAC) Motor
(5) Disconnect vapor purge hose, brake booster
hose, speed control servo hose, positive crankcase
ventilation (PCV) hose.
(6) Disconnect generator electrical connections.
(7) Disconnect air conditioning compressor electri-
cal connections.
(8) Disconnect left and right radio suppressor
straps.
(9) Disconnect and remove ignition coil towers.
(10) Remove top oil dipstick tube retaining bolt
and ground strap.
(11) Bleed fuel system. Refer to FUEL SYSTEM.
(12) Remove fuel rail.
(13) Remove throttle body assembly and mounting
bracket.
(14) Drain cooling system below coolant tempera-
ture level. Refer to COOLING SYSTEM.
(15) Remove the heater hoses from the engine
front cover and the heater core.
(16) Unclip and remove heater hoses and tubes
from intake manifold (Fig. 50).
(17) Remove coolant temperature sensor. Refer to
FUEL SYSTEM.
(18) Remove intake manifold retaining fasteners in
reverse order of tightening sequence (Fig. 51).
(19) Remove intake manifold.
INSTALLATION
(1) Install intake manifold gaskets.
(2) Install intake manifold.
(3) Install intake manifold retaining bolts and
tighten in sequence shown in (Fig. 51) to 12 N´m
(105 in. lbs.).
(4) Install left and right radio suppressor straps.
(5) Install throttle body assembly.
(6) Install throttle cable bracket.
(7) Connect throttle cable and speed control cable
to throttle body.
(8) Install fuel rail.
(9) Install ignition coil towers.
Fig. 48 Body Ground StrapÐRight Side Removal /
Installation
1 ± NUT
2 ± A/C ACCUMULATOR
3 ± GROUND STRAP
Fig. 49 Body Ground StrapÐLeft Side Removal /
Installation
1 ± NUT
2 ± GROUND STRAP
3 ± BRAKE BOOSTER
DN4.7L ENGINE 9 - 35
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine (10) Position and install heater hoses and tubes
onto intake manifold.
(11) Install the heater hoses to the heater core and
engine front cover.(12) Connect electrical connectors for the following
components:
²Manifold Absolute Pressure (MAP) Sensor
²Intake Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Coolant Temperature (CTS) Sensor
²Idle Air Control (IAC) Motor
²Ignition coil towers
²Fuel injectors
(13) Install top oil dipstick tube retaining bolt and
ground strap.
(14) Connect generator electrical connections.
(15) Connect Vapor purge hose, Brake booster
hose, Speed control servo hose, Positive crankcase
ventilation (PCV) hose.
(16) Fill cooling system.
(17) Install resonator assembly and air inlet hose.
(18) Connect negative cable to battery.
EXHAUST MANIFOLDS
RIGHT EXHAUST MANIFOLD
REMOVAL
(1) Disconnect negative cable for battery.
(2) Remove air cleaner assembly, resonator assem-
bly and air inlet hose.
(3) Remove accessory drive belt. Refer to COOL-
ING SYSTEM.
(4) Remove A/C compressor from mounting and set
aside.
(5) Remove A/C accumulator support bracket fas-
tener.
(6) Drain coolant below heater hose level. Refer to
COOLING SYSTEM.
(7) Remove heater hoses at engine.
(8) Remove fasteners attaching exhaust manifold
heat shield.
(9) Remove heat shield.
(10) Remove upper exhaust manifold attaching fas-
teners.
(11) Raise vehicle on hoist.
(12) Disconnect exhaust pipe from manifold.
(13) Remove fasteners attaching starter. Move
starter aside.
(14) Remove lower exhaust manifold attaching fas-
teners.
(15) Remove exhaust manifold and gasket (Fig.
52). Manifold is removed from below the engine com-
partment.
Fig. 50 Heater Hoses and Tubes Removal /
Installation
1 ± HEATER HOSES AND TUBES
2 ± ROUTING/RETAINING CLIPS
Fig. 51 Intake Manifold Tightening Sequence
9 - 36 4.7L ENGINEDN
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine CRANKSHAFT MAIN BEARINGS
DESCRIPTION
Main bearings are located in the cylinder block.
One half of the main bearing is located in the crank-
shaft main bore the other half of the matching bear-
ing is located in the main bearing cap (Fig. 9). There
are five main bearings. Number three main bearing
is flanged, this flange controls crankshaft thrust.
OPERATION
The main bearings encircle the crankshaft main
bearing journals, this aligns the crankshaft to the
centerline of the engine and allows the crankshaft to
turn without wobbling or shaking therefore eliminat-
ing vibration. The main bearings are available in
standard and undersizes.
CRANKSHAFT
DESCRIPTION
The crankshaft is of a cast nodular steel splayed
type design, with five main bearing journals. The
crankshaft is located at the bottom of the engine
block and is held in place with five main bearing
caps. The number 3 counterweight is the location for
journal size identification (Fig. 10).
OPERATION
The crankshaft transfers force generated by com-
bustion within the cylinder bores to the flywheel or
flexplate.
DIAGNOSIS AND TESTING
ENGINE DIAGNOSISÐINTRODUCTION
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 Service DiagnosisÐMechanical Chart
and the Service DiagnosisÐPerformance Chart, for
possible causes and corrections of malfunctions. Refer
to FUEL SYSTEM for the 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
²Cylinder Combustion Pressure Leakage Test
²Cylinder Head Gasket Failure Diagnosis
²Intake Manifold Leakage Diagnosis
²Lash Adjuster (Tappet) Noise Diagnosis
²Engine Oil Leak Inspection
Fig. 9 Main Bearing Orientation
Fig. 10 Crankshaft with Journal Size Identification
DN5.9L ENGINE 9 - 141
DESCRIPTION AND OPERATION (Continued)