1999 DODGE DURANGO Idler arm

Downloaded from www.Manualslib.com manuals search engine ENGINE
TABLE OF CONTENTS
page page
4.7L ENGINE.............................. 1
5.2L ENGINE............................. 865.9L ENGINE............................ 135
4.7L ENGINE
TABLE OF CONTENTS
page page
DESCRIPTION AND OPERATION
ENGINE.................................2
ENGINE LUBRICATION SYSTEM..............3
CYLINDER BLOCK.........................5
CRANKSHAFT............................5
PISTON AND CONNECTING ROD.............5
CYLINDER HEAD..........................5
VALVE GUIDES...........................5
VALVES.................................5
VALVE STEM SEAL........................5
VALVE SPRING...........................6
HYDRAULIC LASH ADJUSTER...............6
TIMING DRIVE SYSTEM....................6
CAMSHAFT..............................6
ROCKER ARM............................6
CYLINDER HEAD COVER...................6
OILPAN.................................7
STRUCTURAL DUST COVER................7
INTAKE MANIFOLD........................7
EXHAUST MANIFOLD......................7
DIAGNOSIS AND TESTING
ENGINE DIAGNOSISÐINTRODUCTION.........7
SERVICE DIAGNOSISÐPERFORMANCE.......8
SERVICE DIAGNOSISÐMECHANICAL.........10
SERVICE DIAGNOSISÐLUBRICATION.........11
INTAKE MANIFOLD LEAKAGE DIAGNOSIS.....11
CYLINDER COMPRESSION PRESSURE TEST . . 11
CYLINDER HEAD GASKET FAILURE
DIAGNOSIS...........................12
CYLINDER COMBUSTION PRESSURE
LEAKAGE TEST........................12
ENGINE OIL LEAK INSPECTION.............13
REAR SEAL AREA LEAKSÐINSPECTION......14
HYDRAULIC LASH ADJUSTER NOISE
DIAGNOSIS...........................14
CHECKING ENGINE OIL PRESSURE..........15SERVICE PROCEDURES
FORM-IN-PLACE GASKETS.................15
ENGINE OIL.............................16
REPAIR DAMAGED OR WORN THREADS......17
CYLINDER BOREÐHONING................18
HYDROSTATIC LOCK.....................18
VALVE SERVICE.........................19
ENGINE TIMINGÐVERIFICATION............19
TIMING CHAINÐMEASURING WEAR.........22
PISTONSÐFITTING.......................22
PISTON RINGSÐFITTING..................24
CONNECTING ROD BEARINGSÐFITTING.....25
CRANKSHAFT MAIN BEARINGS.............27
REMOVAL AND INSTALLATION
ENGINE MOUNTSÐLEFT AND RIGHT.........28
ENGINE MOUNTÐREAR...................29
STRUCTURAL COVER.....................30
ENGINE ASSEMBLY.......................31
INTAKE MANIFOLD.......................35
EXHAUST MANIFOLDS....................36
CYLINDER HEAD COVER..................38
ROCKER ARMS..........................40
CYLINDER HEADS........................41
VALVE SPRINGS AND SEALS...............46
HYDRAULIC LASH ADJUSTER..............46
CRANKSHAFT DAMPER...................47
TIMING CHAIN COVER....................48
TIMING CHAIN AND SPROCKETS............49
IDLER SHAFTÐTIMING DRIVE..............55
CAMSHAFTSÐIN VEHICLE.................56
CRANKSHAFT MAIN BEARINGS.............61
OIL PAN 4X2 VEHICLE.....................61
OIL PAN 4X4 VEHICLE.....................64
PISTON AND CONNECTING ROD............65
CRANKSHAFT...........................67
FLEXPLATE.............................69
DNENGINE 9 - 1

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 (4) For rocker arm installation on cylinders 1 and
7 Rotate the crankshaft until cylinder #2 is at TDC
compression stroke.
(5) Using special tool 8516 press downward on the
valve spring, install rocker arm (Fig. 56).
(6) Install the cylinder head cover.
CYLINDER HEADS
CYLINDER HEADÐLEFT
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Raise the vehicle on a hoist.
(3) Disconnect the exhaust pipe at the left side
exhaust manifold.
(4) Drain the engine coolant. Refer to COOLING
SYSTEM.
(5) Lower the vehicle.
(6) Remove the intake manifold. Refer to proce-
dure in this section.
(7) Remove the cylinder head cover. Refer to proce-
dure in this section.
(8) Remove the fan shroud and fan blade assembly.
Refer to COOLING SYSTEM.
(9) Remove accessory drive belt. Refer to COOL-
ING SYSTEM.
(10) Remove the power steering pump and set
aside.(11) Rotate the crankshaft until the damper timing
mark is aligned with TDC indicator mark (Fig. 57).
(12) Verify the V8 mark on the camshaft sprocket
is at the 12 o'clock position (Fig. 59). Rotate the
crankshaft one turn if necessary.
(13) Remove the crankshaft damper. Refer to
Crankshaft Damper in this section.
(14) Remove the timing chain cover. Refer to pro-
cedure in this section.
(15) Lock the secondary timing chains to the idler
sprocket using Special Tool 8515 (Fig. 58).
NOTE: Mark the secondary timing chain prior to
removal to aid in installation.
(16) Mark the secondary timing chain, one link on
each side of the V8 mark on the camshaft drive gear
(Fig. 59).
(17) Remove the left side secondary chain ten-
sioner. Refer to Timing Chain and Sprockets in this
section.
(18) Remove the cylinder head access plug (Fig.
60).
(19) Remove the left side secondary chain guide.
Refer to Timing Chain and Sprockets in this section.
(20) Remove the retaining bolt and the camshaft
drive gear.
Fig. 56 Rocker ArmÐRemoval
1 ± CAMSHAFT
2 ± SPECIAL TOOL 8516
Fig. 57 Engine Top Dead Center (TDC) Indicator
Mark
1 ± TIMING CHAIN COVER
2 ± CRANKSHAFT TIMING MARKS
DN4.7L ENGINE 9 - 41
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine CAUTION: Do not allow the engine to rotate. Severe
damage to the valve train can occur.CAUTION: Do not overlook the four smaller bolts at
the front of the cylinder head. Do not attempt to
remove the cylinder head without removing these
four bolts.
NOTE: The cylinder head is attached to the cylinder
block with fourteen bolts.
Fig. 59 Camshaft Sprocket V8 Marks
1 ± LEFT CYLINDER HEAD
2 ± RIGHT CYLINDER HEAD
Fig. 60 Cylinder Head Access Plugs
1 ± RIGHT CYLINDER HEAD ACCESS PLUG
2 ± LEFT CYLINDER HEAD ACCESS PLUG
Fig. 58 Using Special Tool 8515 to Hold Chains to
Idler Sprocket.
1 ± LOCK ARM
2 ± RIGHT CAMSHAFT CHAIN
3 ± SECONDARY CHAINS RETAINING PINS (4)
4 ± IDLER SPROCKET
5 ± LEFT CAMSHAFT CHAIN
6 ± SPECIAL TOOL 8515
9 - 42 4.7L ENGINEDN
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine CAUTION: Care should be taken not to damage
camshaft target wheel. Do not hold target wheel
while loosening or tightening camshaft sprocket.
Do not place the target wheel near a magnetic
source of any kind. A damaged or magnetized tar-
get wheel could cause a vehicle no start condition.
CAUTION: Do not forcefully rotate the camshafts or
crankshaft independently of each other. Damaging
intake valve to piston contact will occur. Ensure
negative battery cable is disconnected to guard
against accidental starter engagement.
(13) Remove left and right camshaft sprocket bolts.
(14) While holding the left camshaft steel tube
with adjustable pliers, (Fig. 80) remove the left cam-
shaft sprocket. Slowly rotate the camshaft approxi-
mately 15 degrees clockwise to a neutral position.
(15) While holding the right camshaft steel tube
with adjustable pliers, (Fig. 81) remove the right
camshaft sprocket. Slowly rotate the camshaft
approximately 45 degrees counterclockwise to a neu-
tral position.
(16) Remove idler sprocket assembly bolt.
(17) Slide the idler sprocket assembly and crank
sprocket forward simultaneously to remove the pri-
mary and secondary chains.
(18) Remove both pivoting tensioner arms and
chain guides.(19) Remove chain tensioner.
Fig. 79 Camshaft Position SensorÐRemoval
1 ± CRANKSHAFT POSITION SENSOR
2 ± CYLINDER HEAD COVER
3 ± CAMSHAFT POSITION SENSOR
4 ± RIGHT SIDE CYLINDER BLOCKFig. 80 Camshaft RotationÐLeft Side
1 ± CAMSHAFT SPROCKET AND CHAIN
2 ± ADJUSTABLE PLIERS
3 ± CAMSHAFT
Fig. 81 Camshaft RotationÐRight Side
1 ± ADJUSTABLE PLIERS
2 ± CAMSHAFT DOWEL
DN4.7L ENGINE 9 - 51
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine INSPECTION OF COMPONENTS
Inspect the following components:
²Sprockets for excessive tooth wear. Some tooth
markings are normal and not a cause for sprocket
replacement.
²Idler sprocket assembly bushing and shaft for
excessive wear.
²Idler sprocket assembly spline joint. The joint
should be tight with no backlash or axial movement.
²Chain guides and tensioner arms. Replace these
parts if grooving in plastic face is more than 1 mm
(0.039 in.) deep. If plastic face is severely grooved or
melted, the tensioner lube jet may be clogged. The
tensioner should be replaced.
²secondary chain tensioner piston and ratcheting
device. Inspect for evidence of heavy contact between
tensioner piston and tensioner arm. If this condition
exist the tensioner tensioner arm and chain should
be replaced.²Primary chain tensioner plastic faces. Replace as
required.
INSTALLATION
(1) Using a vise, lightly compress the secondary
chain tensioner piston until the piston step is flush
with the tensioner body. Using a pin or suitable tool,
release ratchet pawl by pulling pawl back against
spring force through access hole on side of tensioner.
While continuing to hold pawl back, Push ratchet
device to approximately 2 mm from the tensioner
body. Install Special Tool 8514 lock pin into hole on
front of tensioner. Slowly open vise to transfer piston
spring force to lock pin (Fig. 83).
(2) Position primary chain tensioner over oil pump
and insert bolts into lower two holes on tensioner
bracket. Tighten bolts to 28 N´m (250 in. lbs.).
Fig. 82 Timing Chain System
1 ± RIGHT CAMSHAFT SPROCKET AND SECONDARY CHAIN
2 ± SECONDARY TIMING CHAIN TENSIONER
3 ± SECONDARY TENSIONER ARM
4 ± LEFT CAMSHAFT SPROCKET AND SECONDARY CHAIN
5 ± CHAIN GUIDE
6 ± TWO PLATED LINKS ON RIGHT CAMSHAFT CHAIN7 ± PRIMARY CHAIN
8 ± IDLER SPROCKET
9 ± CRANKSHAFT SPROCKET
10 ± PRIMARY CHAIN TENSIONER
11 ± TWO PLATED LINKS ON LEFT CAMSHAFT CHAIN
12 ± SECONDARY TENSIONER ARM
9 - 52 4.7L ENGINEDN
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine CAUTION: Overtightening the tensioner arm torxT
bolt can cause severe damage to the cylinder head.
Tighten torxTbolt to specified torque only.
(3) Install right side chain tensioner arm. Apply
MopartLock N, Seal to torxtbolt, tighten bolt to 17
N´m (150 in. lbs.).
NOTE: The silver bolts retain the guides to the cyl-
inder heads and the black bolts retain the guides to
the engine block.
(4) Install the left side chain guide. Tighten the
bolts to 28 N´m (250 in. lbs.).
CAUTION: Overtightening the tensioner arm torxT
bolt can cause severe damage to the cylinder head.
Tighten torxTbolt to specified torque only.
(5) Install left side chain tensioner arm. Apply
MopartLock N, Seal to torxtbolt, tighten bolt to 17
N´m (150 in. lbs.).
(6) Install the right side chain guide. Tighten the
bolts to 28 N´m (250 in. lbs.).
(7) Install both secondary chains onto the idler
sprocket. Align two plated links on the secondary
chains to be visible through the two lower openings
on the idler sprocket (4 o'clock and 8 o'clock). Oncethe secondary timing chains are installed, position
special tool 8515 to hold chains in place for installa-
tion (Fig. 84).
(8) Align primary chain double plated links with
the timing mark at 12 o'clock on the idler sprocket.
Align the primary chain single plated link with the
timing mark at 6 o'clock on the crankshaft sprocket
(Fig. 82).
(9) Lubricate idler shaft and bushings with clean
engine oil.
(10) Install all chains, crankshaft sprocket, and
idler sprocket as an assembly (Fig. 85). After guiding
both secondary chains through the block and cylinder
head openings, affix chains with a elastic strap or the
equivalent, This will maintain tension on chains to
aid in installation.
NOTE: It will be necessary to slightly rotate cam-
shafts for sprocket installation.
(11) Align left camshaft sprocket ªLº dot to plated
link on chain.
(12) Align right camshaft sprocket ªRº dot to
plated link on chain.
CAUTION: Remove excess oil from the camshaft
sprocket bolt. Failure to do so can result in over-
torque of bolt resulting in bolt failure.
Fig. 83 Resetting Secondary Chain Tensioners
1 ± VISE
2 ± INSERT LOCK PIN
3 ± RATCHET PAWL
4 ± RATCHET
5 ± PISTON
Fig. 84 Installing Secondary Timing Chains on Idler
Sprocket
1 ± LOCK ARM
2 ± RIGHT CAMSHAFT CHAIN
3 ± SECONDARY CHAINS RETAINING PINS (4)
4 ± IDLER SPROCKET
5 ± LEFT CAMSHAFT CHAIN
6 ± SPECIAL TOOL 8515
DN4.7L ENGINE 9 - 53
REMOVAL AND INSTALLATION (Continued)