Downloaded from www.Manualslib.com manuals search engine 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.
(3) Secure the throttle in the wide-open position.
(4) Disable the fuel system. (Refer to Group 14,
Fuel System for the correct procedure)
(5) Disconnect the ignition coil.
(6) Insert a compression pressure gauge and rotate
the engine with the engine starter motor for three
revolutions.
(7) Record the compression pressure on the 3rd
revolution. Continue the test for the remaining cylin-
ders.
Refer to Engine Specifications for the correct
engine compression pressures.
CYLINDER HEAD GASKET FAILURE DIAGNOSIS
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:
²Loss of engine power
²Engine misfiring
²Poor fuel economy
²Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
²Engine overheating
²Loss of coolant
²Excessive steam (white smoke) emitting from
exhaust
²Coolant 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.
CYLINDER COMBUSTION PRESSURE LEAKAGE
TEST
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
²Exhaust and intake valve leaks (improper seat-
ing).
²Leaks between adjacent cylinders or into water
jacket.
²Any causes for combustion/compression pressure
loss.
(1) Check the coolant level and fill as required. DO
NOT install the radiator cap.
(2) Start and operate the engine until it attains
normal operating temperature, then turn the engine
OFF.
(3) Remove the spark plugs.
(4) Remove the oil filler cap.
(5) Remove the air cleaner.
(6)
Calibrate the tester according to the manufacturer's
instructions. The shop air source for testing should main-
tain 483 kPa (70 psi) minimum, 1,379 kPa (200 psi) maxi-
mum and 552 kPa (80 psi) recommended.
(7) Perform the test procedures on each cylinder
according to the tester manufacturer's instructions.
While testing, listen for pressurized air escaping
through the throttle body, tailpipe and 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.
Refer to the Cylinder Combustion Pressure Leak-
age Test Diagnosis chart.
9 - 12 4.7L ENGINEDN
DIAGNOSIS AND TESTING (Continued)
Downloaded from www.Manualslib.com manuals search engine Fig. 13 Securing Timing Chain Tensioners Using Timing Chain Wedge
1 ± LEFT CYLINDER HEAD
2 ± RIGHT CYLINDER HEAD3 ± SPECIAL TOOL 8350 WEDGE
4 ± SPECIAL TOOL 8350 WEDGE
Fig. 12 Camshaft Sprocket V8 Marks
1 ± LEFT CYLINDER HEAD
2 ± RIGHT CYLINDER HEAD
DN4.7L ENGINE 9 - 21
SERVICE PROCEDURES (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 INSTALLATION
(1) Thoroughly clean the idler shaft bore.
(2) Position the idler shaft in the bore.
NOTE: The two lubrication holes in the idler shaft
do not require any special alignment.
NOTE: Before using the retaining bolt to install the
idler shaft, coat the threads and the pilot on the
idler shaft with clean engine oil.
(3) Using the primary idler sprocket retaining bolt
and washer, carefully draw the idler shaft into the
bore until fully seated.
(4) Coat the idler shaft with clean engine oil and
install the timing chains and sprockets. Refer to pro-
cedure in this section.
CAMSHAFTSÐIN VEHICLE
LEFT CAMSHAFT
REMOVAL
CAUTION: When the timing chain is removed and
the cylinder heads are still installed, DO NOT force-
fully rotate the camshafts or crankshaft indepen-
dently of each other. Severe valve and/or piston
damage can occur.CAUTION: When removing the cam sprocket, tim-
ing chains or camshaft, Failure to use Special Tool
8350 will result in hydraulic tensioner ratchet over
extension, requiring timing chain cover removal to
reset the tensioner ratchet.
(1) Remove cylinder head cover. Refer to Cylinder
Head Cover in this section.
(2) Set engine to TDC cylinder #1, camshaft
sprocket V8 marks at the 12 o'clock position.
(3) Mark one link on the secondary timing chain
on both sides of the V8 mark on the camshaft
sprocket to aid in installation.
CAUTION: Do not hold or pry on the camshaft tar-
get wheel (Located on the right side camshaft
sprocket) for any reason, Severe damage will occur
to the target wheel resulting in a vehicle no start
condition.
(4) Loosen butDO NOTremove the camshaft
sprocket retaining bolt. Leave the bolt snug against
the sprocket.
NOTE: The timing chain tensioners must be
secured prior to removing the camshaft sprockets.
Failure to secure tensioners will allow the tension-
ers to extend, requiring timing chain cover removal
in order to reset tensioners.
CAUTION: Do not force wedge past the narrowest
point between the chain strands. Damage to the
tensioners may occur.
(5) Position Special Tool 8350 timing chain wedge
between the timing chain strands, tap the tool to
securely wedge the timing chain against the ten-
sioner arm and guide (Fig. 91).
(6) Hold the camshaft with adjustable pliers while
removing the camshaft sprocket bolt and sprocket
(Fig. 92).
(7) Using the pliers, gently allow the camshaft to
rotate 15É clockwise until the camshaft is in the neu-
tral position (no valve load).
(8) Starting at the outside working inward, loosen
the camshaft bearing cap retaining bolts 1/2 turn at
a time. Repeat until all load is off the bearing caps.
CAUTION: DO NOT STAMP OR STRIKE THE CAM-
SHAFT BEARING CAPS. SEVERE DAMAGE WILL
OCCUR TO THE BEARING CAPS.
NOTE: When the camshaft is removed the rocker
arms may slide downward, mark the rocker arms
before removing camshaft.
Fig. 90 Removing Idler Shaft
1 ± IDLER SHAFT
2 ± SPECIAL TOOL 8517
9 - 56 4.7L ENGINEDN
REMOVAL AND INSTALLATION (Continued)
Downloaded from www.Manualslib.com manuals search engine (9) Remove the camshaft bearing caps and the
camshaft.INSTALLATION
(1) Lubricate camshaft journals with clean engine
oil.
NOTE: Position the left side camshaft so that the
camshaft sprocket dowel is near the 1 o'clock posi-
tion, This will place the camshaft at the neutral
position easing the installation of the camshaft
bearing caps.
(2) Position the camshaft into the cylinder head.
(3) Install the camshaft bearing caps, hand tighten
the retaining bolts.
(4) Working in
1¤2turn increments, tighten the
bearing cap retaining bolts starting with the middle
cap working outward (Fig. 93).
(5) Torque the camshaft bearing cap retaining
bolts to 11 N´m (100 in. lbs.).
(6) Position the camshaft drive gear into the tim-
ing chain aligning the V8 mark between the two
marked chain links (Two links marked during
removal) (Fig. 94).
(7) Using the adjustable pliers, rotate the cam-
shaft until the camshaft sprocket dowel is aligned
with the slot in the camshaft sprocket. Install the
sprocket onto the camshaft (Fig. 95).
Fig. 91 Securing Timing Chain Tensioners Using Timing Chain Wedge
1 ± LEFT CYLINDER HEAD
2 ± RIGHT CYLINDER HEAD3 ± SPECIAL TOOL 8350 WEDGE
4 ± SPECIAL TOOL 8350 WEDGE
Fig. 92 Camshaft Sprocket and Chain
1 ± CAMSHAFT SPROCKET AND CHAIN
2 ± ADJUSTABLE PLIERS
3 ± CAMSHAFT
DN4.7L ENGINE 9 - 57
REMOVAL AND INSTALLATION (Continued)
Downloaded from www.Manualslib.com manuals search engine (2) Set engine to TDC cylinder #1, camshaft
sprocket V8 marks at the 12 o'clock position.
(3) Mark one link on the secondary timing chain
on both sides of the V8 mark on the camshaft
sprocket to aid in installation.
CAUTION: Do not hold or pry on the camshaft tar-
get wheel for any reason, Severe damage will occur
to the target wheel. A damaged target wheel could
cause a vehicle no start condition.
(4) Loosen butDO NOTremove the camshaft
sprocket retaining bolt. Leave bolt snug against
sprocket.
NOTE: The timing chain tensioners must be
secured prior to removing the camshaft sprockets.
Failure to secure tensioners will allow the tension-
ers to extend, requiring timing chain cover removal
in order to reset tensioners.
CAUTION: Do not force wedge past the narrowest
point between the chain strands. Damage to the
tensioners may occur.
(5) Position Special Tool 8350 timing chain wedge
between the timing chain strands. Tap the tool to
securely wedge the timing chain against the ten-
sioner arm and guide (Fig. 97).
(6) Remove the camshaft position sensor (Fig. 98).(7) Hold the camshaft with adjustable pliers while
removing the camshaft sprocket bolt and sprocket
(Fig. 99).
(8) Using the pliers, gently allow the camshaft to
rotate 45É counter-clockwise until the camshaft is in
the neutral position (no valve load).
(9) Starting at the outside working inward, loosen
the camshaft bearing cap retaining bolts 1/2 turn at
a time. Repeat until all load is off the bearing caps.
CAUTION: DO NOT STAMP OR STRIKE THE CAM-
SHAFT BEARING CAPS. SEVERE DAMAGE WILL
OCCUR TO THE BEARING CAPS.
NOTE: When the camshaft is removed the rocker
arms may slide downward, mark the rocker arms
before removing camshaft.
(10) Remove the camshaft bearing caps and the
camshaft.
Fig. 95 Camshaft Sprocket Installation
1 ± ADJUSTABLE PLIERS
2 ± CAMSHAFT DOWEL
Fig. 96 Tightening Left Side Cam Sprocket
Retaining Bolt
1 ± TORQUE WRENCH
2 ± CAMSHAFT SPROCKET
3 ± LEFT CYLINDER HEAD
4 ± SPECIAL TOOL 6958 SPANNER WITH ADAPTER PINS 8346
DN4.7L ENGINE 9 - 59
REMOVAL AND INSTALLATION (Continued)
Downloaded from www.Manualslib.com manuals search engine Fig. 97 Securing Timing Chain Tensioners Using Timing Chain Wedge
1 ± LEFT CYLINDER HEAD
2 ± RIGHT CYLINDER HEAD3 ± SPECIAL TOOL 8350 WEDGE
4 ± SPECIAL TOOL 8350 WEDGE
Fig. 98 Camshaft Position Sensor
1 ± CRANKSHAFT POSITION SENSOR
2 ± CYLINDER HEAD COVER
3 ± CAMSHAFT POSITION SENSOR
4 ± RIGHT SIDE CYLINDER BLOCKFig. 99 Camshaft Sprocket and Chain
1 ± ADJUSTABLE PLIERS
2 ± SPROCKET BOLT
3 ± CAMSHAFT SPROCKET AND CHAIN
4 ± CAMSHAFT
9 - 60 4.7L ENGINEDN
REMOVAL AND INSTALLATION (Continued)
Downloaded from www.Manualslib.com manuals search engine (2) Install new bolt and washer assemblies in the
remaining holes (Fig. 42). Start at the center arm
and work outward. Tighten the bolts and nuts to 24
N´m (18 ft. lbs.) torque.
(3) Position three washers, heat shield and nuts on
the right side exhaust manifold. Tighten nuts to 24
N´m (18 ft. lbs.).
(4) Position two washers, heat shield and nuts on
the left side exhaust manifold. Tighten nuts to 24
N´m (18 ft. lbs.).
(5) Raise the vehicle.
(6) Assemble the exhaust pipe to the exhaust man-
ifold and secure with bolts, nuts and washers.
Tighten these nuts to 27 N´m (20 ft. lbs.) torque.(7) Lower the vehicle.
(8) Connect the battery negative cable.
CYLINDER HEAD COVER
A steel backed silicon gasket is used with the cyl-
inder head cover (Fig. 43). This gasket can be used
again.
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Disconnect closed ventilation system and evap-
oration control system from cylinder head cover.
(3) Remove the air inlet hose.
(4) Remove cylinder head cover and gasket. The
gasket may be used again.
INSTALLATION
(1) The cylinder head cover gasket can be used
again. Install the gasket onto the head rail.
Fig. 40 Exhaust Manifold Heat ShieldÐRight Side
1 ± WASHER
2 ± NUT AND WASHER
3 ± EXHAUST MANIFOLD HEAT SHIELD
Fig. 41 Exhaust Manifold Heat ShieldÐLeft Side
1 ± WASHER
2 ± NUT AND WASHER
3 ± EXHAUST MANIFOLD HEAT SHIELD
Fig. 42 Exhaust Manifold InstallationÐ5.9L Engine
1 ± EXHAUST MANIFOLD (LEFT)
2 ± BOLTS & WASHERS
3 ± NUTS & WASHERS
4 ± EXHAUST MANIFOLD (RIGHT)
5 ± BOLTS & WASHERS
Fig. 43 Cylinder Head Cover Gasket
1 ± CYLINDER HEAD COVER GASKET
9 - 106 5.2L ENGINEDN
REMOVAL AND INSTALLATION (Continued)