head light DODGE DURANGO 1998 1.G User Guide

Downloaded from www.Manualslib.com manuals search engine EXHAUST MANIFOLD
DESCRIPTION
The exhaust manifolds are constructed of cast iron
and are LOG type with balanced flow (Fig. 5). One
exhaust manifold is attached to each cylinder head.
OPERATION
The exhaust manifolds collect the engine exhaust
exiting the combustion chambers, then channels the
exhaust gases to the exhaust pipes attached to the
manifolds.
INTAKE MANIFOLD
DESCRIPTION
The aluminum intake manifold (Fig. 6) is a single
plane design with equal length runners and uses a
separate plenum, therefore the manifold does have a
plenum gasket. It also uses separate flange gaskets
and front and rear cross-over gaskets. Extreme caremust be used when sealing the gaskets to ensure
that excess sealant does not enter the intake runners
causing a restriction. Whenever the intake manifold
is removed inspect the plenum pan for evidence of
excess oil buildup, this condition indicates that the
plenum pan gasket is leaking.
OPERATION
The intake manifold, meters and delivers air to the
combustion chambers allowing the fuel delivered by
the fuel injectors to ignite, thus producing power.
1 ± OIL DEFLECTOR TAB
2 ± BOLT
3 ± ROCKER ARM PIVOT
4 ± ROCKER ARM
5 ± DRIP OILING FOR VALVE TIP
6 ± CYLINDER HEAD BOSS
7 ± TO MAIN BEARINGS
8 ± TO CAMSHAFT BEARINGS
9 ± ROCKER ARM
10 ± HOLLOW PUSH ROD
11 ± TAPPET
12 ± TO CONNECTING ROD BEARINGS
13 ± OIL INTAKE14 ± OIL PUMP
15 ± OIL FILTER
16 ± CRANKSHAFT
17 ± FROM OIL PUMP
18 ± OIL TO FILTER
19 ± OIL FROM FILTER TO SYSTEM
20 ± PASSAGE TO CAMSHAFT REAR BEARING
21 ± RIGHT OIL GALLERY
22 ± PLUG
23 ± OIL PASSAGE FOR OIL PRESSURE INDICATOR LIGHT
24 ± OIL SUPPLY VIA HOLLOW PUSH ROD SUPPLY IS FROM
OIL GALLERY METERED THROUGH HYDRAULIC TAPPET
25 ± OIL SUPPLY FROM HOLLOW PUSH ROD
Fig. 5 Exhaust ManifoldsÐV-8 Gas Engines Typical
1 ± EXHAUST MANIFOLD (LEFT)
2 ± BOLTS & WASHERS
3 ± NUTS & WASHERS
4 ± EXHAUST MANIFOLD (RIGHT)
5 ± BOLTS & WASHERS
Fig. 6 Intake Manifold and Throttle BodyÐV-8 Gas
Engines Typical
1 ± FUEL RAIL ASSEMBLY
2 ± FUEL RAIL MOUNTING BOLTS
3 ± FUEL RAIL CONNECTING HOSES
DN5.2L ENGINE 9 - 89
DESCRIPTION AND OPERATION (Continued)

Downloaded from www.Manualslib.com manuals search engine (3) Inspect the valve seat with Prussian blue to
determine where the valve contacts the seat. To do
this, coat valve seatLIGHTLYwith 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 15É stone. If the blue is transferred to bottom
edge of valve face raise valve seat with a 60É stone.(4) When seat is properly positioned the width of
intake seats should be 1.016-1.524 mm (0.040-0.060
inch). The width of the exhaust seats should be
1.524-2.032 mm (0.060-0.080 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. 22). 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.
MEASURING TIMING CHAIN STRETCH
NOTE: To access timing chain Refer to Timing
Chain Cover in Removal and Installation Section.
(1) Place a scale next to the timing chain so that
any movement of the chain may be measured.
(2) Place a torque wrench and socket over cam-
shaft sprocket attaching bolt. Apply torque in the
direction of crankshaft rotation to take up slack; 41
N´m (30 ft. lbs.) torque with cylinder head installed
or 20 N´m (15 ft. lbs.) torque with cylinder head
removed. With a torque applied to the camshaft
Fig. 20 Intake and Exhaust Valves
1 ± MARGIN
2 ± VALVE SPRING RETAINER LOCK GROOVE
3 ± STEM
4±FACE
Fig. 21 Refacing Valve Seats
1±STONE
2 ± PILOT
3 ± VALVE SEAT
4 ± SHROUD
Fig. 22 Testing Valve Spring for Compressed
Length
1 ± TORQUE WRENCH
2 ± VALVE SPRING TESTER
DN5.2L ENGINE 9 - 97
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine (13) Disconnect the heater hoses and bypass hose.
(14) Remove the closed crankcase ventilation and
evaporation control systems.
(15) Remove intake manifold bolts.
(16) Lift the intake manifold and throttle body out
of the engine compartment as an assembly.
(17) Remove and discard the flange side gaskets
and the front and rear cross-over gaskets.
(18) Remove the throttle body bolts and lift the
throttle body off the intake manifold (Fig. 35). Dis-
card the throttle body gasket.
INSTALLATION
(1) If the plenum pan was removed, position pan
gasket and pan.
(2) Install plenum pan retaining bolts. (Fig. 36).
(3) Tighten plenum pan mounting bolts as follows:
²Step 1. Tighten bolts to 5.4 N´m (24 in. lbs.)
²Step 2. Tighten bolts to 9.5 N´m (84 in. lbs.)
²Step 3. Check all bolts are at 9.5 N´m (84 in.
lbs.)
(4) Using a new gasket, install the throttle body
onto the intake manifold. Tighten the bolts to 23 N´m
(200 in. lbs.) torque.
(5) Apply a bead of Mopar Silicone Rubber Adhe-
sive Sealant, or equivalent, to the four corner joints.
The sealant bead height should be slightly higher
than the cross-over gaskets, approximately 5 mm (0.2
in). An excessive amount of sealant is not required to
ensure a leak proof seal, and an excessive amount of
sealant may reduce the effectiveness of the flange
gasket.
(6) Install the front and rear cross-over gaskets
onto the engine (Fig. 37).
(7) Install the flange gaskets. Ensure that the ver-
tical port alignment tab is resting on the deck face ofthe block. Also the horizontal alignment tabs must be
in position with the mating cylinder head gasket tabs
(Fig. 38). The words MANIFOLD SIDE should be vis-
ible on the center of each flange gasket.
(8) Carefully lower intake manifold into position
on the cylinder block and cylinder heads. long studs
at the front and rear of the manifold will help to
align the intake manifold. After intake manifold is in
Fig. 35 Throttle Body Assembly
1 ± FUEL RAIL ASSEMBLY
2 ± FUEL RAIL MOUNTING BOLTS
3 ± FUEL RAIL CONNECTING HOSES
Fig. 36 Plenum Pan Bolt Tightening Sequence
Fig. 37 Cross-Over Gaskets
1 ± FRONT CROSS-OVER GASKET
2 ± REAR CROSS-OVER GASKET
9 - 104 5.2L ENGINEDN
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine (6) To align the bearing cap, use cap slot, align-
ment dowel and cap bolts. DO NOT remove excess
material after assembly. DO NOT strike rear cap
more than 2 times for proper engagement.
(7) Install the rear main bearing cap with cleaned
and oiled cap bolts. Alternately tighten ALL cap bolts
to 115 N´m (85 ft. lbs.) torque.
(8) Install oil pump.
(9) Apply MopartSilicone Rubber Adhesive Seal-
ant, or equivalent, at bearing cap to block joint to
provide cap to block and oil pan sealing (Fig. 72).
Apply enough sealant until a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(10) Immediately install the oil pan.
LOWER SEAL
REMOVAL
(1) Remove the oil pan.
(2) Remove the oil pump from the rear main bear-
ing cap.
(3) Remove the rear main bearing cap and discard
the old lower seal.
INSTALLATION
(1) Clean the rear main cap mating surfaces
including the oil pan gasket groove.
(2) Carefully install a new upper seal (refer to
Upper Seal Replacement - Crankshaft Installed pro-
cedure above).
(3) Lightly oil the new lower seal lips with engine
oil.
(4) Install a new lower seal in bearing cap with
the white paint facing the rear of engine.
(5) Apply 5 mm (0.20 in) drop of MopartGasket
Maker, or equivalent, on each side of the rear main
bearing cap (Fig. 71). DO NOT over apply sealant or
allow the sealant to contact the rubber seal. Assem-
ble bearing cap to cylinder block immediately after
sealant application.
(6) To align the bearing cap, use cap slot, align-
ment dowel and cap bolts. DO NOT remove excess
material after assembly. DO NOT strike rear cap
more than 2 times for proper engagement.
(7) Install the rear main bearing cap with cleaned
and oiled cap bolts. Alternately tighten the cap bolts
to 115 N´m (85 ft. lbs.) torque.
(8) Install oil pump.
(9) Apply MopartSilicone Rubber Adhesive Seal-
ant, or equivalent, at bearing cap to block joint to
provide cap to block and oil pan sealing (Fig. 72).
Apply enough sealant until a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(10) Immediately install the oil pan.
ENGINE CORE OIL AND CAMSHAFT PLUGS
Engine core plugs have been pressed into the oil
galleries behind the camshaft thrust plate (Fig. 73).
This will reduce internal leakage and help maintain
higher oil pressure at idle.
REMOVAL
(1) Using a blunt tool such as a drift or a screw-
driver and a hammer, strike the bottom edge of the
cup plug (Fig. 74).
(2) With the cup plug rotated, grasp firmly with
pliers or other suitable tool and remove plug (Fig.
74).
INSTALLATION
Thoroughly clean inside of cup plug hole in cylin-
der block or head. Be sure to remove old sealer.
Be certain the new plug is cleaned of all oil or
grease.
(1) Coat edges of plug and core hole with Mopart
Gasket Maker, or equivalent.
CAUTION: DO NOT drive cup plug into the casting,
as restricted coolant flow can result and cause seri-
ous engine problems.
(2) Using proper plug drive, drive cup plug into
hole. The sharp edge of the plug should be at least
0.50 mm (0.020 in.) inside the lead-in chamfer.
(3) It is not necessary to wait for curing of the
sealant. The cooling system can be filled and the
vehicle placed in service immediately.
Fig. 73 Location of Cup Plugs in Oil Galleries
1 ± CUP PLUGS
9 - 120 5.2L ENGINEDN
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine CYLINDER BLOCK
DISASSEMBLE
With Engine removed from vehicle:
(1) Remove the cylinder heads. refer to Cylinder
Head in this section for correct procedure.
(2) Remove the exhaust manifolds. Refer to
Exhaust Manifolds in this section.
(3) Remove the oil pan. Refer to Oil Pan in this
section.
(4) Remove the piston and connecting rod assem-
blies. Refer to Piston and Connecting Rod in this sec-
tion.
(5) Remove the crankshaft. Refer to Crankshaft in
this section.
(6) Remove the core plugs.
ASSEMBLE
(1) Install the core plugs.
(2) Install the crankshaft.
(3) Install the piston and connecting rods.
(4) Install the oil pan.
(5) Install the cylinder heads.
(6) Install the exhaust manifolds.
(7) Install the intake manifold.
(8) Install the engine into the vehicle.
CLEANING AND INSPECTION
CYLINDER HEAD COVER
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.
CYLINDER HEAD ASSEMBLY
CLEANING
Clean all surfaces of cylinder block and cylinder
heads.
Clean cylinder block front and rear gasket surfaces
using a suitable solvent.
INSPECTION
Inspect all surfaces with a straightedge if there is
any reason to suspect leakage. If out-of-flatness
exceeds 0.00075 mm/mm (0.00075 inch/inch) times
the span length in inches in any direction, either
replace head or lightly machine the head surface.
FOR EXAMPLE:A 305 mm (12 inch) span is
0.102 mm (0.004 inch) out-of-flat. The allowable out-
of-flat is 305 X 0.00075 (12 X 0.00075) equals 0.23
mm (0.009 inch). This amount of out-of-flat is accept-
able.
The cylinder head surface finish should be
1.78-3.00 microns (70-125 microinches).
PISTON AND CONNECTING ROD ASSEMBLY
INSPECTION
Check the crankshaft connecting rod journal for
excessive wear, taper and scoring.
Check the cylinder block bore for out-of-round,
taper, scoring and scuffing.
Check the pistons for taper and elliptical shape
before they are fitted into the cylinder bore (Fig. 83).
OIL PAN
CLEANING
Clean the block and pan gasket surfaces.
Trim or remove excess sealant film in the rear
main cap oil pan gasket groove.DO NOT remove
the sealant inside the rear main cap slots.
If present, trim excess sealant from inside the
engine.
Fig. 82 Oil Pump
1 ± INNER ROTOR AND SHAFT
2 ± BODY
3 ± DISTRIBUTOR DRIVESHAFT (REFERENCE)
4 ± COTTER PIN
5 ± RETAINER CAP
6 ± SPRING
7 ± RELIEF VALVE
8 ± LARGE CHAMFERED EDGE
9 ± BOLT
10 ± COVER
11 ± OUTER ROTOR
9 - 124 5.2L ENGINEDN
DISASSEMBLY AND ASSEMBLY (Continued)

Downloaded from www.Manualslib.com manuals search engine DESCRIPTION AND OPERATION
ENGINE
DESCRIPTION
The 5.9 Liter (360 CID) eight-cylinder engine is a
V-Type lightweight, single cam, overhead valve
engine with hydraulic roller tappets. This engine is
designed for unleaded fuel.
The engine lubrication system consists of a rotor
type oil pump and a full flow oil filter.
The cylinders are numbered from front to rear; 1,
3, 5, 7 on the left bank and 2, 4, 6, 8 on the right
bank. The firing order is 1-8-4-3-6-5-7-2 (Fig. 1).
The engine serial number is stamped into a
machined pad located on the left, front corner of the
cylinder block. When component part replacement is
necessary, use the engine type and serial number for
reference (Fig. 2).
ENGINE LUBRICATION SYSTEM
DESCRIPTION
A gear-type positive displacement pump (Fig. 3) is
mounted at the underside of the rear main bearing
cap. The pump uses a pick-up tube and screen
assembly to gather engine oil from the oil pan.
OPERATION
The pump draws oil through the screen and inlet
tube from the sump at the rear of the oil pan. The oil
is driven between the drive and idler gears and
pump body, then forced through the outlet to the
block. An oil gallery in the block channels the oil to
the inlet side of the full flow oil filter. After passing
through the filter element, the oil passes from the
center outlet of the filter through an oil gallery that
channels the oil up to the main gallery, which
extends the entire length on the right side of the
block. The oil then goes down to the No. 1 main bear-
ing, back up to the left side of the block, and into the
oil gallery on the left side of the engine.
Galleries extend downward from the main oil gal-
lery to the upper shell of each main bearing. The
crankshaft is drilled internally to pass oil from the
main bearing journals to the connecting rod journals.
Each connecting rod bearing has half a hole in it, oil
passes through the hole when the rods rotate and the
hole lines up, oil is then thrown off as the rod
rotates. This oil throwoff lubricates the camshaft
lobes, distributor drive gear, cylinder walls, and pis-
ton pins.
Fig. 1 Firing Order
Fig. 2 Engine Identification Number
Fig. 3 Positive Displacement Oil PumpÐTypical
1 ± INNER ROTOR AND SHAFT
2 ± BODY
3 ± DISTRIBUTOR DRIVESHAFT (REFERENCE)
4 ± COTTER PIN
5 ± RETAINER CAP
6 ± SPRING
7 ± RELIEF VALVE
8 ± LARGE CHAMFERED EDGE
9 ± BOLT
10 ± COVER
11 ± OUTER ROTOR
9 - 136 5.9L ENGINEDN

Downloaded from www.Manualslib.com manuals search engine EXHAUST MANIFOLD
DESCRIPTION
The exhaust manifolds are constructed of cast iron
and are LOG type with balanced flow (Fig. 5). One
exhaust manifold is attached to each cylinder head.
OPERATION
The exhaust manifolds collect the engine exhaust
exiting the combustion chambers, then channels the
exhaust gases to the exhaust pipes attached to the
manifolds.
INTAKE MANIFOLD
DESCRIPTION
The aluminum intake manifold (Fig. 6) is a single
plane design with equal length runners and uses a
separate plenum, therefore the manifold does have a
plenum gasket. It also uses separate flange gaskets
and front and rear cross-over gaskets. Extreme caremust be used when sealing the gaskets to ensure
that excess sealant does not enter the intake runners
causing a restriction. Whenever the intake manifold
is removed inspect the plenum pan for evidence of
excess oil buildup, this condition indicates that the
plenum pan gasket is leaking.
OPERATION
The intake manifold, meters and delivers air to the
combustion chambers allowing the fuel delivered by
the fuel injectors to ignite, thus producing power.
1 ± OIL DEFLECTOR TAB
2 ± BOLT
3 ± ROCKER ARM PIVOT
4 ± ROCKER ARM
5 ± DRIP OILING FOR VALVE TIP
6 ± CYLINDER HEAD BOSS
7 ± TO MAIN BEARINGS
8 ± TO CAMSHAFT BEARINGS
9 ± ROCKER ARM
10 ± HOLLOW PUSH ROD
11 ± TAPPET
12 ± TO CONNECTING ROD BEARINGS
13 ± OIL INTAKE14 ± OIL PUMP
15 ± OIL FILTER
16 ± CRANKSHAFT
17 ± FROM OIL PUMP
18 ± OIL TO FILTER
19 ± OIL FROM FILTER TO SYSTEM
20 ± PASSAGE TO CAMSHAFT REAR BEARING
21 ± RIGHT OIL GALLERY
22 ± PLUG
23 ± OIL PASSAGE FOR OIL PRESSURE INDICATOR LIGHT
24 ± OIL SUPPLY VIA HOLLOW PUSH ROD SUPPLY IS FROM
OIL GALLERY METERED THROUGH HYDRAULIC TAPPET
25 ± OIL SUPPLY FROM HOLLOW PUSH ROD
Fig. 5 Exhaust ManifoldsÐV-8 Gas Engines Typical
1 ± EXHAUST MANIFOLD (LEFT)
2 ± BOLTS & WASHERS
3 ± NUTS & WASHERS
4 ± EXHAUST MANIFOLD (RIGHT)
5 ± BOLTS & WASHERS
Fig. 6 Intake Manifold and Throttle BodyÐV-8 Gas
Engines Typical
1 ± FUEL RAIL ASSEMBLY
2 ± FUEL RAIL MOUNTING BOLTS
3 ± FUEL RAIL CONNECTING HOSES
DN5.9L ENGINE 9 - 139
DESCRIPTION AND OPERATION (Continued)

Downloaded from www.Manualslib.com manuals search engine 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.
INSPECTION (ENGINE OIL LEAKS IN GENERAL)
Begin with a through visual inspection of the
engine, particularly at the area of the suspected leak.
If an oil leak source is not readily identifiable, the
following steps should be followed:
(1) Do not clean or degrease the engine at this
time because some solvents may cause rubber to
swell, temporarily stopping the leak.
(2) Add an oil-soluble dye (use as recommended by
manufacturer). Start the engine and let idle for
approximately 15 minutes. Check the oil dipstick to
be sure the dye is thoroughly mixed as indicated
with a bright yellow color under a black light source.
(3) Using a black light, inspect the entire engine
for fluorescent dye, particularly at the suspected area
of oil leak. If the oil leak is found and identified,
repair per service manual instructions.
(4) If dye is not observed, drive the vehicle at var-
ious speeds for approximately 24km (15 miles), and
repeat previous step.
(5) If the oil leak source is not positively identified
at this time, proceed with the air leak detection test
method as follows:
(6) Disconnect the breather cap to air cleaner hose
at the breather cap end. Cap or plug breather cap
nipple.
(7) Remove the PCV valve from the cylinder head
cover. Cap or plug the PCV valve grommet.
(8) Attach an air hose with pressure gauge and
regulator to the dipstick tube.
CAUTION: Do not subject the engine assembly to
more than 20.6 kpa (3 PSI) of test pressure.
(9) Gradually apply air pressure from 1 psi to 2.5
psi maximum while applying soapy water at the sus-
pected source. Adjust the regulator to the suitable
test pressure that provide the best bubbles which
will pinpoint the leak source. If the oil leak is
detected and identified, repair per service manual
procedures.
(10) If the leakage occurs at the rear oil seal area,
refer to the section, Inspection for Rear Seal Area
Leak.
(11) If no leaks are detected, turn off the air sup-
ply and remove the air hose and all plugs and caps.
Install the PCV valve and breather cap hose. Proceed
to next step.(12) Clean the oil off the suspect oil leak area
using a suitable solvent. Drive the vehicle at various
speeds approximately 24 km (15 miles). Inspect the
engine for signs of an oil leak by using a black light.
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 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 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.
DN5.9L ENGINE 9 - 147
DIAGNOSIS AND TESTING (Continued)

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) 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)