1998 DODGE DURANGO vehicle

Downloaded from www.Manualslib.com manuals search engine 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.
Check the oil level after the engine reaches normal
operating temperature. Allow 5 minutes to stabilize
oil level, check dipstick. The oil level 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.
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 theplunger 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.
(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
After cleaning and inspection, test each tappet for
specified leak-down rate tolerance to ensure zero-lash
operation (Fig. 11).
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.
ENGINE OIL PRESSURE
(1) Remove oil pressure sending unit.
9 - 148 5.9L ENGINEDN
DIAGNOSIS AND TESTING (Continued)

Downloaded from www.Manualslib.com manuals search engine (2) Install Oil Pressure Line and Gauge Tool
C-3292. Start engine and record pressure. Refer to
Oil Pressure in Engine Specifications for the proper
pressures.
SERVICE PROCEDURES
FORM-IN-PLACE GASKETS
There are several places where form-in-place gas-
kets are used on the engine.DO NOT use form-in-
place gasket material unless specified.Care
must be taken when applying form-in-place gaskets.
Bead size, continuity and location are of great impor-
tance. Too thin a bead can result in leakage while too
much can result in spill-over. A continuous bead of
the proper width is essential to obtain a leak-free
joint.
Two types of form-in-place gasket materials are
used in the engine area (Mopar Silicone Rubber
Adhesive Sealant and Mopar Gasket Maker). Each
have different properties and cannot be used inter-
changeably.
MOPAR SILICONE RUBBER ADHESIVE SEALANT
Mopar Silicone Rubber Adhesive Sealant, normally
black in color, is available in 3 ounce tubes. Moisture
in the air causes the sealant material to cure. This
material is normally used on flexible metal flanges.
It has a shelf life of a year and will not properly cure
if over aged. Always inspect the package for the expi-
ration date before use.
MOPAR GASKET MAKER
Mopar Gasket Maker, normally red in color, is
available in 6 cc tubes. This anaerobic type gasket
material cures in the absence of air when squeezed
between smooth machined metallic surfaces. It will
not cure if left in the uncovered tube. DO NOT use
on flexible metal flanges.
SURFACE PREPARATION
Parts assembled with form-in-place gaskets may be
disassembled without unusual effort. In some
instances, it may be necessary to lightly tap the part
with a mallet or other suitable tool to break the seal
between the mating surfaces. A flat gasket scraper
may also be lightly tapped into the joint but care
must be taken not to damage the mating surfaces.
Scrape or wire brush all gasket surfaces to remove
all loose material. Inspect stamped parts to ensure
gasket rails are flat. Flatten rails with a hammer on
a flat plate, if required. Gasket surfaces must be free
of oil and dirt. Make sure the old gasket material is
removed from blind attaching holes.
GASKET APPLICATION
Assembling parts using a form-in-place gasket
requires care.
Mopar Silicone Rubber Adhesive Sealant should be
applied in a continuous bead approximately 3 mm
(0.12 inch) in diameter. All mounting holes must be
circled. For corner sealing,a3or6mm(1/8 or 1/4
inch) drop is placed in the center of the gasket con-
tact area. Uncured sealant may be removed with a
shop towel. Components should be torqued in place
while the sealant is still wet to the touch (within 10
minutes). The use of a locating dowel is recom-
mended during assembly to prevent smearing the
material off location.
Mopar Gasket Maker should be applied sparingly
to one gasket surface. The sealant diameter should
be 1.00 mm (0.04 inch) or less. Be certain the mate-
rial surrounds each mounting hole. Excess material
can easily be wiped off. Components should be
torqued in place within 15 minutes. The use of a
locating dowel is recommended during assembly to
prevent smearing the material off location.
ENGINE PERFORMANCE
It is important that the vehicle is operating to its
optimum performance level to maintain fuel economy
and the lowest emission levels. If vehicle is not oper-
ating to these standards, refer to Engine Diagnosis
outlined in this section. The following procedures can
assist in achieving the proper engine diagnosis.
(1) Test cranking amperage draw. Refer to Electri-
cal Group 8B, Cold Cranking Test.
Fig. 11 Leak-Down Tester
1 ± POINTER
2 ± WEIGHTED ARM
3 ± RAM
4 ± CUP
5 ± HANDLE
6 ± PUSH ROD
DN5.9L ENGINE 9 - 149
DIAGNOSIS AND TESTING (Continued)

Downloaded from www.Manualslib.com manuals search engine (2) Check intake manifold bolt torque.
(3) Perform cylinder compression test. Refer to
Cylinder Compression Pressure Test in the Engine
Diagnosis area of this section.
(4) Clean or replace spark plugs as necessary and
adjust gap as specified in Electrical Group 8D.
Tighten to specifications.
(5) Test resistance of spark plug cables. Refer to
Electrical Group 8D, Spark Plug Cables.
(6) Inspect the primary wires. Test coil output volt-
age and primary resistance. Replace parts as neces-
sary. Refer to Electrical Group 8D, for specifications.
(7) Test fuel pump for pressure. Refer to Group 14,
Fuel System Specifications.
(8) The air filter elements should be replaced as
specified in Lubrication and Maintenance, Group 0.
(9) Inspect crankcase ventilation system as out
lined in Group 0, Lubrication and Maintenance. For
emission controls see Group 25, Emission Controls
for service procedures.
(10) Road test vehicle as a final test.
ENGINE OIL
WARNING: NEW OR USED ENGINE OIL CAN BE
IRRITATING TO THE SKIN. AVOID PROLONGED OR
REPEATED SKIN CONTACT WITH ENGINE OIL.
CONTAMINANTS IN USED ENGINE OIL, CAUSED BY
INTERNAL COMBUSTION, CAN BE HAZARDOUS TO
YOUR HEALTH. THOROUGHLY WASH EXPOSED
SKIN WITH SOAP AND WATER. DO NOT WASH
SKIN WITH GASOLINE, DIESEL FUEL, THINNER, OR
SOLVENTS, HEALTH PROBLEMS CAN RESULT. DO
NOT POLLUTE, DISPOSE OF USED ENGINE OIL
PROPERLY.
ENGINE OIL SPECIFICATION
CAUTION: Do not use non-detergent or straight
mineral oil when adding or changing crankcase
lubricant. Engine failure can result.
API SERVICE GRADE CERTIFIED
In gasoline engines, use an engine oil that is API
Service Grade Certified (Fig. 12). Standard engine oil
identification notations have been adopted to aid in
the proper selection of engine oil. The identifying
notations are located on the label of engine oil plastic
bottles and the top of engine oil cans. MOPAR only
provides engine oil that conforms to this certification.
SAE VISCOSITY
An SAE viscosity grade is used to specify the vis-
cosity of engine oil. SAE 10W-30 specifies a multiple
viscosity engine oil. These are specified with a dualSAE viscosity grade which indicates the cold-to-hot
temperature viscosity range. When choosing an
engine oil, consider the range of temperatures the
vehicle will be operated in before the next oil change.
Select an engine oil that is best suited to your area's
particular ambient temperature range and variation
(Fig. 13).
ENERGY CONSERVING OIL
An Energy Conserving type oil is recommended for
gasoline engines. The designation of ENERGY CON-
SERVING is located on the label of an engine oil con-
tainer.
OIL LEVEL INDICATOR (DIPSTICK)
The engine oil level indicator is located at the right
front of the engine, left of the generator on 5.9L
engines (Fig. 14).
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil,
oil foaming and oil pressure loss can result.
To ensure proper lubrication of an engine, the
engine oil must be maintained at an acceptable level.
The acceptable levels are indicated between the ADD
and SAFE marks on the engine oil dipstick.
(1) Position vehicle on level surface.
Fig. 12 Engine Oil Container Standard Notations
Fig. 13 Temperature/Engine Oil Viscosity
Recommendation
9 - 150 5.9L ENGINEDN
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine (2) With engine OFF, allow approximately ten min-
utes for oil to settle to bottom of crankcase, remove
engine oil dipstick.
(3) Wipe dipstick clean.
(4) Install dipstick and verify it is seated in the
tube.
(5) Remove dipstick, with handle held above the
tip, take oil level reading.
(6) Add oil only if level is below the ADD mark on
dipstick.
ENGINE OIL CHANGE
Change engine oil at mileage and time intervals
described in the Maintenance Schedule. This infor-
mation can be found in your owner's manual.
TO CHANGE ENGINE OIL
Run engine until achieving normal operating tem-
perature.
(1) Position the vehicle on a level surface and turn
engine off.
(2) Hoist and support vehicle on safety stands.
Refer to Hoisting and Jacking Recommendations.
(3) Remove oil fill cap.
(4) Place a suitable drain pan under crankcase
drain.
(5) Remove drain plug from crankcase and allow
oil to drain into pan. Inspect drain plug threads for
stretching or other damage. Replace drain plug and
gasket if damaged.
(6) Install drain plug in crankcase.(7) Lower vehicle and fill crankcase with specified
type and amount of engine oil described in this sec-
tion.
(8) Install oil fill cap.
(9) Start engine and inspect for leaks.
(10) Stop engine and inspect oil level.
ENGINE OIL FILTER CHANGE
FILTER SPECIFICATION
All engines are equipped with a high quality full-
flow, disposable type oil filter. DaimlerChrysler Cor-
poration recommends a Mopar or equivalent oil filter
be used.
OIL FILTER REMOVAL
(1) Position a drain pan under the oil filter.
(2) Using a suitable oil filter wrench loosen filter.
(3) Rotate the oil filter counterclockwise to remove
it from the cylinder block oil filter boss (Fig. 15).
(4) When filter separates from adapter nipple, tip
gasket end upward to minimize oil spill. Remove fil-
ter from vehicle.
(5) With a wiping cloth, clean the gasket sealing
surface (Fig. 16) of oil and grime.
OIL FILTER INSTALLATION
(1) Lightly lubricate oil filter gasket with engine
oil or chassis grease.
(2) Thread filter onto adapter nipple. When gasket
makes contact with sealing surface, (Fig. 16) hand
tighten filter one full turn, do not over tighten.
(3) Add oil, verify crankcase oil level and start
engine. Inspect for oil leaks.
REPAIR DAMAGED OR WORN THREADS
CAUTION: Be sure that the tapped holes maintain
the original center line.
Fig. 14 Engine Oil Dipstick LocationÐ5.9L Engines
1 ± CYLINDER HEAD COVER
2 ± ENGINE OIL FILL-HOLE CAP
3 ± DIPSTICK
4 ± ENGINE OIL FILTER
5 ± FILTER BOSS
Fig. 15 Oil Filter RemovalÐTypical
1 ± ENGINE OIL FILTER
2 ± OIL FILTER WRENCH
DN5.9L ENGINE 9 - 151
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine Upper and lower No.3 bearing halves are flanged
to carry the crankshaft thrust loads. They are NOT
interchangeable with any other bearing halves in the
engine (Fig. 31). Bearing shells are available in stan-
dard 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 AND INSTALLATION
ENGINE FRONT MOUNTS
REMOVALÐ2WD
(1) Disconnect the negative cable from the battery.
(2) Raise hood and position fan to assure clearance
for radiator top tank and hose.
CAUTION: DO NOT lift the engine by the intake
manifold.
(3) Install engine lifting fixture.
(4) Raise vehicle on hoist.
(5) Remove the insulator through bolt (Fig. 32)
(Fig. 33).
(6) Raise engine with lifting fixture SLIGHTLY.
Remove insulator retaining bolts and remove the
insulator assembly.
(7) Remove insulator heat shield and transfer to
new insulator.
INSTALLATIONÐ2WD
(1) With the engine raised SLIGHTLY, position
insulator assembly onto the engine block and install
bolts (Fig. 32) (Fig. 33). Tighten the bolts to 41 N´m
(30 ft. lbs.) torque.
(2) Lower engine with lifting fixture while guiding
insulator assembly into the engine insulator bracket
(Fig. 34).
(3) Install insulator to bracket thru-bolt. Tighten
the thru-bolt nut to 68 N´m (50 ft. lbs.) torque.
(4) Remove lifting fixture.
(5) Connect the negative cable to the battery.
Fig. 29 Compression Ring Chamfer Location
(Typical)
1 ± CHAMFER
2 ± TOP COMPRESSION RING
3 ± SECOND COMPRESSION RING
4 ± PISTON
5 ± CHAMFER
Fig. 30 Proper Ring Installation
1 ± OIL RING SPACER GAP
2 ± SECOND COMPRESSION RING GAP OIL RING RAIL GAP
(TOP)
3 ± OIL RING RAIL GAP (BOTTOM)
4 ± TOP COMPRESSION RING GAP
Fig. 31 Main Bearing Identification
9 - 158 5.9L ENGINEDN
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine REMOVALÐ4WD
On 4WD vehicles the engine front support brackets
attach directly to engine block and the axle housing.
The brackets provide a solid interconnection for these
units (Fig. 35) (Fig. 36). Engine must be supported
during any service procedures involving the front
support assemblies.
(1) Disconnect the negative cable from the battery.
(2) Raise vehicle on hoist.
(3) Install engine lifting (support) fixture.
(4) Remove front axle. (Refer to Group 3, Differen-
tial and Driveline in this publication.)
(5)Left mount insulator only.Remove starter
wires and starter motor assembly.
(6) Remove insulator to frame through bolt (Fig.
37).
(7) Raise engine slightly.
(8) Remove upper insulator to support bracket
stud nut and insulator to support through bolt.
(9) Remove engine mount insulator (Fig. 35) (Fig.
36).
(10) If engine support bracket is to be removed/re-
placed, remove support bracket to transmission bell
housing bolt(s) and three (3) support bracket to
engine block bolts. Remove support bracket (Fig. 35)
(Fig. 36).
Fig. 32 Engine Right Front Insulator MountÐ2WD
Vehicles
1 ± HEAT SHIELD
2 ± INSULATOR
Fig. 33 Engine Left Front Insulator MountÐ2WD
Vehicles
1 ± HEAT SHIELD
2 ± INSULATOR
Fig. 34 Engine Mount Insulator at Frame
1 ± NUT
2 ± INSULATOR
3 ± FRAME
4 ± THROUGH BOLT
DN5.9L ENGINE 9 - 159
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine INSTALLATIONÐ4WD
(1) If engine support brackets were removed,
install them and their fasteners (Fig. 35) (Fig. 36).
Tighten support bracket to block bolts to 41 N´m (30
ft. lbs.). Tighten support bracket to transmission bell-
housing bolt(s) to 88 N´m (65 ft. lbs.).
(2) Install Engine mount insulator and tighten
insulator to support bracket nut to 41 N´m (30 ft.
lbs.). Tighten insulator to support bracket through
bolt nut to 102 N´m (75 ft. lbs.).
(3) Lower engine and install insulator to frame
through bolt and nut (Fig. 37). Tighten nut to 95 N´m
(70 ft. lbs.).
(4) Install starter motor and mounting bolts.
Tighten bolts to 68 N´m (50 ft. lbs.).
(5) Connect starter wires.
(6) Remove engine lifting (support) fixture.
(7) Install front axle assembly (Refer to Group 3,
Differential and Driveline).
(8) Lower the vehicle.
(9) Connect the negative cable to the battery.
ENGINE REAR SUPPORT
REMOVALÐ2WD
(1) Disconnect the negative cable from the battery.
(2) Raise the vehicle on a hoist.
(3) Support the transmission with a jack.
(4) Remove engine support bracket and insulator
thru-bolt (Fig. 38).
(5) Raise the transmission and engine slightly.
(6) Remove stud nuts attaching insulator to cross-
member (Fig. 38). Remove insulator.
INSTALLATIONÐ2WD
(1) If the engine support bracket was removed,
position the bracket to the transmission extension
(Fig. 38). Tighten the bolts to 68 N´m (50 ft. lbs.)
torque.
(2) Install the insulator onto crossmember. Tighten
the stud nuts to 41 N´m (30 ft. lbs) torque.
(3) Lower the transmission and engine while align-
ing the engine support bracket to the insulator.
(4) Install thru-bolt in bracket and insulator.
Tighten thru-bolt nut to 68 N´m (50 ft. lbs.) torque.
(5) Remove transmission jack.
(6) Lower the vehicle.
(7) Connect the negative cable to the battery.
Fig. 35 Right Engine Mount Insulator and Support
BracketÐ4WD Vehicles
1 ± ENGINE SUPPORT BRACKET
2 ± INSULATOR
3 ± FRONT AXLE
Fig. 36 Left Engine Mount Insulator and Support
BracketÐ4WD Vehicles
1 ± ENGINE SUPPORT BRACKET
2 ± INSULATOR
3 ± FRONT AXLE
9 - 160 5.9L ENGINEDN
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine REMOVALÐ4WD
(1) Disconnect the negative cable from the battery.
(2) Raise the vehicle on a hoist.
(3) Support the transmission with a transmission
jack.
(4) Remove stud nuts holding the insulator to the
crossmember (Fig. 39).
(5) Raise rear of transmission SLIGHTLY.
(6) Remove bolts holding the insulator to the insu-
lator bracket (Fig. 39). Remove the insulator.
INSTALLATIONÐ4WD
(1) If the insulator bracket was removed, install
the bracket to the transmission (Fig. 39). Tighten the
bolts to 28 N´m (250 in. lbs.) torque.
(2) Install the bolts holding insulator to insulator
bracket. Tighten the bolts to 28 N´m (250 in. lbs.)
torque.
(3) Lower rear of transmission while aligning the
insulator studs into the mounting support bracket.Install stud nuts and tighten to 28 N´m (250 in. lbs.)
torque.
(4) Remove the transmission jack.
(5) Lower the vehicle.
(6) Connect the negative cable to the battery.
ENGINE ASSEMBLY
REMOVAL
(1) Scribe hood hinge outlines on hood. Remove the
hood.
(2) Remove the battery.
(3) Drain cooling system. Refer to COOLING SYS-
TEM.
(4) Remove the air cleaner assembly and air inlet
hose.
(5) Disconnect the radiator and heater hoses.
(6) Set fan shroud aside.
(7) Remove the vacuum lines.
(8) Remove the distributor cap and wiring.
(9) Disconnect the accelerator linkage.
(10) Remove throttle body.
(11) Perform the Fuel System Pressure release
procedure Refer to FUEL SYSTEM.
(12) Disconnect the fuel lines.
(13) Disconnect the starter wires.
(14) Disconnect the oil pressure wire.
Fig. 37 Engine Mount Insulator at FrameÐ4WD
Vehicles
1 ± NUT
2 ± ENGINE SUPPORT BRACKET
3 ± INSULATOR
4 ± NUT
5 ± THROUGH BOLT
6 ± FRAME
7 ± FRONT AXLE
Fig. 38 Rear InsulatorÐ2WD Vehicles
1 ± ENGINE SUPPORT BRACKET
2 ± THROUGH BOLT
3 ± CROSSMEMBER
4 ± INSULATOR
5 ± TRANSMISSION EXTENSION
DN5.9L ENGINE 9 - 161
REMOVAL AND INSTALLATION (Continued)