1999 DODGE DURANGO Group 8D

Downloaded from www.Manualslib.com manuals search engine OIL PAN
DESCRIPTION
The engine oil pan is made of laminated steel and
has a single plane sealing surface. The sandwich
style oil pan gasket has an integrated windage tray
and steel carrier. The sealing area of the gasket is
molded with rubber and is designed to be reused as
long as the gasket is not cut, torn or ripped.
STRUCTURAL DUST COVER
DESCRIPTION
The structural dust cover is made of die cast alu-
minum and joins the lower half of the transmission
bell housing to the engine bedplate.
OPERATION
The structural cover provides additional power-
train stiffness and reduces noise and vibration.
INTAKE MANIFOLD
DESCRIPTION
The intake manifold is made of a composite mate-
rial and features long runners which maximizes low
end torque. The intake manifold uses single plane
sealing which consist of eight individual press in
place port gaskets to prevent leaks. Eight studs and
two bolts are used to fasten the intake to the head.
EXHAUST MANIFOLD
DESCRIPTION
The exhaust manifolds are log style with a pat-
ented flow enhancing design to maximize perfor-mance. The exhaust manifolds are made of high
silicon molybdenum cast iron. A perforated core
graphite exhaust manifold gasket is used to improve
sealing to the cylinder head. The exhaust manifolds
are covered by a three layer laminated heat shield
for thermal protection and noise reduction. The heat
shields are fastened with a torque prevailing nut
that is backed off slightly to allow for the thermal
expansion of the exhaust manifold.
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 per-
formance (e.g., engine idles rough and stalls) or
mechanical (e.g., a strange noise).
Refer to the Service DiagnosisÐPerformance chart
and the Service DiagnosisÐMechanical chart for pos-
sible causes and corrections of malfunctions. Refer to
Group 14, 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 diagnosis:
²Cylinder Compression Pressure Test.
²Cylinder Combustion Pressure Leakage Test.
²Engine Cylinder Head Gasket Failure Diagnosis.
²Intake Manifold Leakage Diagnosis.
DN4.7L ENGINE 9 - 7
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 CONDITION POSSIBLE CAUSE CORRECTION
ENGINE LOSS OF POWER 1. Incorrect ignition timing. 1. Refer to Group 8D, Ignition
System.
2. Worn or burned distributor rotor. 2. Replace distributor rotor.
3. Worn distributor shaft. 3. Refer to Group 8D, Ignition
System.
4. Dirty or incorrectly gapped spark
plugs.4. Refer to Group 8D, Ignition
System.
5. Dirt or water in fuel system. 5. Clean system and replace fuel
filter.
6. Faulty fuel pump. 6. Refer to Group 14, Fuel System.
7. Blown cylinder head gasket. 7. Replace cylinder head gasket.
8. Low compression. 8. Test compression, repair as
necessary.
9. Burned, warped or pitted valves. 9. Replace as necessary.
10. Plugged or restricted exhaust
system.10. Inspect and replace as
necessary.
11. Faulty ignition cables. 11. Replace as necessary.
12. Faulty coil. 12. Refer to Group 8D, Ignition
System.
13. Incorrect cam timing. 13. Refer to Valve Timing in this
section.
ENGINE MISSES ON
ACCELERATION1. Spark plugs dirty or incorrectly
gapped.1. Refer to Group 8D, Ignition
System.
2. Incorrect ignition timing. 2. Refer to Group 8D, Ignition
System.
3. Dirt in fuel system. 3. Clean fuel system.
4. Burned, warped or pitted valves. 4. Replcae as necessary.
5. Faulty coil. 5. Refer to Group 8D, Ignition
System.
6. Incorrect cam timing. 6. Refer to Valve Timing in this
section.
ENGINE MISSES AT HIGH SPEED 1. Spark plugs dirty or incorrectly
gapped.1. Refer to Group 8D, Ignition
System.
2. Worn Distributor Shaft. 2. Refer to Group 8D, Ignition
System.
3. Worn or burned distributor rotor. 3. Replace distributor rotor.
4. Faulty coil. 4. Refer to Group 8D, Ignition
System.
5. Incorrect ignition timing. 5. Refer to Group 8D, Ignition
System.
6. Dirt or water in fuel system. 6. Clean system and replace fuel
filter.
7. Incorrect cam timing. 7. Refer to Valve Timing in this
section.
DN4.7L ENGINE 9 - 9
DIAGNOSIS AND TESTING (Continued)

Downloaded from www.Manualslib.com manuals search engine SERVICE DIAGNOSISÐMECHANICAL
CONDITION POSSIBLE CAUSES CORRECTIONS
NOISY VALVES 1. High or low oil level in
crankcase.1. Refer to Group 0, Lubrication and
Maintenance.
2. Thin or diluted oil. 2. Change oil and filter.
3. Low oil pressure. 3. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
4. Dirt in lash adjusters. 4. Clean lash adjusters.
5. Bent push rods. 5. Replace as necessary.
6. Worn rocker arms. 6. Replace as necessary.
7. Worn tappets 7. Replace as necessary.
8. Worn valve guides. 8. Refer to Valve Service in this
section.
9. Excessive runout of valve seats
on valve faces.9. Service valves and valve seats.
Refer to Valve Service in this
section.
CONNECTING ROD NOISE 1. Insufficient oil supply. 1. Refer to Group 0, Lubrication and
maintenance.
2. Low oil pressure. 2. Refer to Group 0, Lubrication and
maintenance.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Connecting rod journal
out-of-round.5. Service or replace crankshaft.
6. Misaligned connecting rods. 6. Replace bent connecting rods.
MAIN BEARING NOISE 1. Insufficient oil supply. 1. Refer to Group 0, Lubrication and
maintenance.
2. Low oil pressure. 2. Refer to Group 0, Lubrication and
maintenance.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Excessive end play. 5. Check No. 3 main bearing for
wear on flanges.
6. Crankshaft journal out-of round. 6. Service or replace crankshaft.
7. Loose flywheel or torque
converter.7. Tighten to correct torque
9 - 10 4.7L ENGINEDN
DIAGNOSIS AND TESTING (Continued)

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 filter runoff, and main bearing cap to cylinder
block mating surfaces.
(4) If no leaks are detected, pressurize the crank-
case as outlined in the, Inspection (Engine oil Leaks
in general)
CAUTION: Do not exceed 20.6 kPa (3 psi).
(5) If the leak is not detected, very slowly turn the
crankshaft and watch for leakage. If a leak is
detected between the crankshaft and seal while
slowly turning the crankshaft, it is possible the
crankshaft seal surface is damaged. The seal area on
the crankshaft could have minor nicks or scratches
that can be polished out with emery cloth.
CAUTION: Use extreme caution when crankshaft
polishing is necessary to remove minor nicks and
scratches. The crankshaft seal flange is especially
machined to complement the function of the rear oil
seal.
(6) For bubbles that remain steady with shaft
rotation, no further inspection can be done until dis-
assembled.
REAR SEAL AREA LEAKSÐINSPECTION
Since it is sometimes difficult to determine the
source of an oil leak in the rear seal area of the
engine, a more involved inspection is necessary. The
following steps should be followed to help pinpoint
the source of the leak.
If the leakage occurs at the crankshaft rear oil seal
area:
(1) Disconnect the battery.
(2) Raise the vehicle.
(3) Remove torque converter or clutch housing
cover and inspect rear of block for evidence of oil.
Use a black light to check for the oil leak:
(a) Circular spray pattern generally indicates
seal leakage or crankshaft damage.
(b) Where leakage tends to run straight down,
possible causes are a porous block, distributor seal,
camshaft bore cup plugs, oil galley pipe plugs, oil
filter runoff, and main bearing cap to cylinder
block mating surfaces. See Group 9, Engines, for
proper repair procedures of these items.
(4) If no leaks are detected, pressurized the crank-
case as outlined in the section, Inspection (Engine oil
Leaks in general)
CAUTION: Do not exceed 20.6 kPa (3 psi).
(5) If the leak is not detected, very slowly turn the
crankshaft and watch for leakage. If a leak is
detected between the crankshaft and seal while
slowly turning the crankshaft, it is possible thecrankshaft seal surface is damaged. The seal area on
the crankshaft could have minor nicks or scratches
that can be polished out with emery cloth.
CAUTION: Use extreme caution when crankshaft
polishing is necessary to remove minor nicks or
scratches. The crankshaft seal flange is specially
machined to complement the function of the rear oil
seal.
(6) For bubbles that remain steady with shaft
rotation, no further inspection can be done until dis-
assembled. Refer to the service DiagnosisÐMechani-
cal, under the Oil Leak row, for components
inspections on possible causes and corrections.
(7) After the oil leak root cause and appropriate
corrective action have been identified, Refer to Group
9, EnginesÐCrankshaft Rear Oil Seals, for proper
replacement procedures.
HYDRAULIC LASH ADJUSTER NOISE
DIAGNOSIS
A tappet-like noise may be produced from several
items. Check the following items.
(1) Engine oil level too high or too low. This may
cause aerated oil to enter the adjusters and cause
them to be spongy.
(2) Insufficient running time after rebuilding cylin-
der head. Low speed running up to 1 hour may be
required.
(3) Turn engine off and let set for a few minutes
before restarting. Repeat this several times after
engine has reached normal operating temperature.
(4) Low oil pressure.
(5) The oil restrictor in cylinder head gasket or the
oil passage to the cylinder head is plugged with
debris.
(6) Air ingested into oil due to broken or cracked
oil pump pick up.
(7) Worn valve guides.
(8) Rocker arm ears contacting valve spring
retainer.
(9) Rocker arm loose, adjuster stuck or at maxi-
mum extension and still leaves lash in the system.
(10) Faulty lash adjuster.
a. Check lash adjusters for sponginess while
installed in cylinder head and cam on camshaft at
base circle. Depress part of rocker arm over adjuster.
Normal adjusters should feel very firm. Spongy
adjusters can be bottomed out easily.
b. Remove suspected lash adjusters, and replace.
c. Before installation, make sure adjusters are at
least partially full of oil. This can be verified by little
or no plunger travel when lash adjuster is depressed.
9 - 14 4.7L ENGINEDN
DIAGNOSIS AND TESTING (Continued)

Downloaded from www.Manualslib.com manuals search engine Damaged or worn threads can be repaired. Essen-
tially, this repair consists of:
²Drilling out worn or damaged threads.
²Tapping the hole with a special Heli-Coil Tap, or
equivalent.
²Installing an insert into the tapped hole to bring
the hole back to its original thread size.
CYLINDER BOREÐHONING
Before honing, stuff plenty of clean shop towels
under the bores and over the crankshaft to keep
abrasive materials from entering the crankshaft
area.
(1) Used carefully, the Cylinder Bore Sizing Hone
C-823, equipped with 220 grit stones, is the best tool
for this job. In addition to deglazing, it will reduce
taper and out-of-round, as well as removing light
scuffing, scoring and scratches. Usually, a few strokes
will clean up a bore and maintain the required lim-
its.
CAUTION: DO NOT use rigid type hones to remove
cylinder wall glaze.
(2) Deglazing of the cylinder walls may be done if
the cylinder bore is straight and round. Use a cylin-
der surfacing hone, Honing Tool C-3501, equipped
with 280 grit stones (C-3501-3810). about 20-60
strokes, depending on the bore condition, will be suf-
ficient to provide a satisfactory surface. Using honing
oil C-3501-3880, or a light honing oil, available from
major oil distributors.
CAUTION: DO NOT use engine or transmission oil,
mineral spirits, or kerosene.
(3) Honing should be done by moving the hone up
and down fast enough to get a crosshatch pattern.The hone marks should INTERSECT at 50É to 60É
for proper seating of rings (Fig. 9).
(4) A controlled hone motor speed between 200 and
300 RPM is necessary to obtain the proper cross-
hatch angle. The number of up and down strokes per
minute can be regulated to get the desired 50É to 60É
angle. Faster up and down strokes increase the cross-
hatch angle.
(5) After honing, it is necessary that the block be
cleaned to remove all traces of abrasive. Use a brush
to wash parts with a solution of hot water and deter-
gent. Dry parts thoroughly. Use a clean, white, lint-
free cloth to check that the bore is clean. Oil the
bores after cleaning to prevent rusting.
HYDROSTATIC LOCK
When an engine is suspected of hydrostatic lock
(regardless of what caused the problem), follow the
steps below.
(1) Perform the Fuel Pressure Release Procedure
(refer to Group 14, Fuel System).
(2) Disconnect the battery negative cable.
(3) Inspect air cleaner, induction system and
intake manifold to ensure system is dry and clear of
foreign material.
(4) Place a shop towel around the spark plugs to
catch any fluid that may possibly be under pressure
in the cylinder head. Remove the plugs from the
engine.
CAUTION: DO NOT use the starter motor to rotate
the crankshaft. Severe damage could occur.
(5) With all spark plugs removed, rotate the crank-
shaft using a breaker bar and socket.
Fig. 8 Oil Filter Sealing SurfaceÐTypical
1 ± SEALING SURFACE
2 ± RUBBER GASKET
3 ± OIL FILTER
Fig. 9 Cylinder Bore Crosshatch Pattern
1 ± CROSSHATCH PATTERN
2 ± INTERSECT ANGLE
9 - 18 4.7L ENGINEDN
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine nal diameter specification (Main Bearing Fitting
Chart). Select inserts required to obtain the specified
bearing-to-journal clearance.
Install the crankshaft into the cylinder block. Refer
to Crankshaft in this section for procedure.
CRANKSHAFT MAIN BEARING SELECTION
(1) Service main bearings are available in three
grades. The chart below identifies the three service
grades available.
REMOVAL AND INSTALLATION
ENGINE MOUNTSÐLEFT AND RIGHT
REMOVAL
(1) Disconnect the negative cable from the battery.
CAUTION: Remove the fan blade, fan clutch and
fan shroud before raising engine. Failure to do so
may cause damage to the fan blade, fan clutch and
fan shroud.
(2) Remove the fan blade, fan clutch and fan
shroud. Refer to Group 7. for procedure.
(3) Remove the engine oil filter.
(4) Support the engine with a suitable jack and a
block of wood across the full width of the engine oil
pan.
(5) Remove the four (4) cylinder block-to-insulator
mount bolts and the nut from the engine insulator
mount through bolt (4x2 Vehicles only) (Fig. 32) (Fig.
33).
(6) Remove the three (3) cylinder block-to-insulator
mount bolts and loosen the nut from the engine insu-
lator mount through bolt (4x4 Vehicles only) (Fig. 34)
(Fig. 35).
(7) Using the jack, raise the engine high enough to
remove the engine insulator mount through bolt and
the insulator mount.
INSTALLATION
(1) Position the insulator mount and install the
insulator mount through bolt.
(2) Lower the engine until the four cylinder block-
to-insulator mount bolts can be installed.
(3) Remove the jack and block of wood.
(4) Torque the cylinder block-to-insulator mount
bolts to 61N´m ( 45 ft. lbs.).
(5) Install and torque the through bolt retaining
nut to 61N´m (45 ft. lbs.).
(6) Install the fan blade, fan clutch and fan
shroud.
GRADE SIZE mm
(in.)FOR USE WITH
MARKING JOURNAL SIZE
A.008 mm U/S 63.488-63.496 mm
(.0004 in.)
U/S(2.4996-2.4999 in.)
BSTANDARD 63.496-63.504 mm
(2.4996-2.4999 in.)
C.008 mm O/S 63.504-63.512 mm
(.0004 in.)
O/S(2.5002-2.5005 in.)
Fig. 32 Engine Insulator Mount 4x2 VehicleÐLeft
Side
1 ± ENGINE INSULATOR MOUNT-LEFT SIDE
2 ± MOUNTING BOLT
Fig. 33 Engine Insulator Mount 4x2 VehicleÐRight
Side
1 ± ENGINE INSULATOR MOUNT-RIGHT SIDE
2 ± MOUNTING BOLT
9 - 28 4.7L ENGINEDN
SERVICE PROCEDURES (Continued)