1998 DODGE RAM 1500 Engine

(7) Remove access plug from left and right cylinder
heads for access to chain guide fasteners (Fig. 109).
(8) Remove the oil fill housing to gain access to the
right side tensioner arm fastener.
(9) Remove crankshaft damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
REMOVAL) and timing chain cover(Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(10) Collapse and pin primary chain tensioner.
CAUTION: Plate behind left secondary chain ten-
sioner could fall into oil pan. Therefore, cover pan
opening.
(11) Remove secondary chain tensioners.
(12) Remove camshaft position sensor (Fig. 110).
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 Special Tool 8428 Camshaft Wrench, remove the
left camshaft sprocket. Slowly rotate the camshaft
approximately 5 degrees clockwise to a neutral posi-
tion.(15) While holding the right camshaft steel tube
with Special Tool 8428 Camshaft Wrench, remove the
right camshaft sprocket.
(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 primary chain tensioner.
INSPECTION
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.
Fig. 109 Cylinder Head Access Plugs
1 - RIGHT CYLINDER HEAD ACCESS PLUG
2 - LEFT CYLINDER HEAD ACCESS PLUG
Fig. 110 Camshaft Position Sensor
1 - CYLINDER HEAD
2 - CAMSAHFT POSITION SENSOR
3 - SCREW
9 - 84 ENGINE - 3.7LDR
TIMING BELT/CHAIN AND SPROCKETS (Continued)

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 (Fig. 111). Slowly open vise to
transfer piston spring force to lock pin.
(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.).
(3) Install right side chain tensioner arm. Install
Torxtbolt. Tighten Torxtbolt to 28 N´m (250 in.
lbs.).
CAUTION: The silver bolts retain the guides to the
cylinder 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.).(5) Install left side chain tensioner arm, and Torxt
bolt. Tighten Torxtbolt to 28 N´m (250 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). Once
the secondary timing chains are installed, position
special tool 8429 to hold chains in place for installa-
tion.
(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.
(9) Lubricate idler shaft and bushings with clean
engine oil.
NOTE: The idler sprocket must be timed to the
counterbalance shaft drive gear before the idler
sprocket is fully seated.
(10) Install all chains, crankshaft sprocket, and
idler sprocket as an assembly (Fig. 112). After guid-
ing both secondary chains through the block and cyl-
inder head openings, affix chains with a elastic strap
or equivalent. This will maintain tension on chains to
aid in installation. Align the timing mark on the
idler sprocket gear to the timing mark on the coun-
terbalance shaft drive gear, then seat idler sprocket
fully (Fig. 113). Before installing idler sprocket bolt,
lubricate washer with oil, and tighten idler sprocket
assembly retaining bolt to 34 N´m (25 ft. lbs.).
Fig. 111 RESETTING SECONDARY CHAIN
TENSIONERS
1 - VISE
2 - INSERT LOCK PIN
3 - RATCHET PAWL
4 - RATCHET
5 - PISTON
Fig. 112 INSTALLING IDLER GEAR, PRIMARY AND
SECONDARY TIMING CHAINS
1 - SPECIAL TOOL 8515
2 - PRIMARY CHAIN IDLER SPROCKET
3 - CRANKSHAFT SPROCKET
DRENGINE - 3.7L 9 - 85
TIMING BELT/CHAIN AND SPROCKETS (Continued)

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.
(13) Remove Special Tool 8429, then attach both
sprockets to camshafts. Remove excess oil from bolts,
then Install sprocket bolts, but do not tighten at this
time.
(14) Verify that all plated links are aligned with
the marks on all sprockets and the ªV6º marks on
camshaft sprockets are at the 12 o'clock position.
CAUTION: Ensure the plate between the left sec-
ondary chain tensioner and block is correctly
installed.
(15) Install both secondary chain tensioners.
Tighten bolts to 28 N´m (250 in. lbs.).
NOTE: Left and right secondary chain tensioners
are not common.(16) Remove all locking pins (3) from tensioners.
CAUTION: After pulling locking pins out of each
tensioner, DO NOT manually extend the tensioner(s)
ratchet. Doing so will over tension the chains,
resulting in noise and/or high timing chain loads.
(17) Using Special Tool 6958, Spanner with Adap-
tor Pins 8346, tighten left (Fig. 114) and right (Fig.
115). camshaft sprocket bolts to 122 N´m (90 ft. lbs.).
(18) Rotate engine two full revolutions. Verify tim-
ing marks are at the follow locations:
²primary chain idler sprocket dot is at 12 o'clock
²primary chain crankshaft sprocket dot is at 6
o'clock
²secondary chain camshaft sprockets ªV6º marks
are at 12 o'clock
²counterbalancer shaft drive gear dot is aligned
to the idler sprocket gear dot
(19) Lubricate all three chains with engine oil.
(20) After installing all chains, it is recommended
that the idler gear end play be checked. The end play
Fig. 113 COUNTERBALANCE SHAFT ALIGNMENT
MARKS
1 - COUNTERBALANCE SHAFT GEAR
2 - TIMING MARK
3 - IDLER SPROCKET GEAR
Fig. 114 TIGHTENING LEFT SIDE CAMSHAFT
SPROCKET BOLT
1 - TORQUE WRENCH
2 - CAMSHAFT SPROCKET
3 - LEFT CYLINDER HEAD
4 - SPECIAL TOOL 6958 SPANNER WITH ADAPTER PINS 8346
9 - 86 ENGINE - 3.7LDR
TIMING BELT/CHAIN AND SPROCKETS (Continued)

must be within 0.10 -0.25 mm (0.004 - 0.010 in.). If
not within specification, the idler gear must be
replaced (Fig. 116).
(21) Install timing chain cover and crankshaft
damper. Refer to procedures.
(22) Install cylinder head covers(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
NOTE: Before installing threaded plug in right cylin-
der head, the plug must be coated with sealant to
prevent leaks.(23) Coat the large threaded access plug with
MopartThread Sealant with Teflon, then install
into the right cylinder head and tighten to 81 N´m
(60 ft. lbs.).
(24) Install the oil fill housing.
(25) Install access plug in left cylinder head.
(26) Install power steering pump(Refer to 19 -
STEERING/PUMP - INSTALLATION).
(27) Fill cooling system(Refer to 7 - COOLING -
STANDARD PROCEDURE).
(28) Connect negative cable to battery.
Fig. 115 TIGHTENING RIGHT SIDE CAMSHAFT
SPROCKET BOLT
1 - TORQUE WRENCH
2 - SPECIAL TOOL 6958 WITH ADAPTER PINS 8346
3 - LEFT CAMSHAFT SPROCKET
4 - RIGHT CAMSHAFT SPROCKETFig. 116 MEASURING IDLER GEAR END PLAY
1 - IDLER SPROCKET ASSEMBLY
2 - DIAL INDICATOR
DRENGINE - 3.7L 9 - 87
TIMING BELT/CHAIN AND SPROCKETS (Continued)

ENGINE - 4.7L
TABLE OF CONTENTS
page page
ENGINE - 4.7L
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - PERFORMANCE...........90
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - MECHANICAL.............92
DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE.............93
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE......93
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - INTRODUCTION...........94
STANDARD PROCEDURE
STANDARD PROCEDURE - REPAIR
DAMAGED OR WORN THREADS.........94
STANDARD PROCEDURE - FORM-IN-
PLACE GASKETS AND SEALERS.........94
REMOVAL.............................95
INSTALLATION.........................97
SPECIFICATIONS
SPECIFICATIONS - 4.7L ENGINE.........99
TORQUE...........................102
SPECIAL TOOLS
4.7L ENGINE........................103
AIR CLEANER ELEMENT
REMOVAL............................107
INSTALLATION........................107
CYLINDER HEAD
DESCRIPTION
DESCRIPTION - CYLINDER HEAD.......107
DESCRIPTION - VALVE GUIDES.........107
REMOVAL
REMOVAL - LEFT CYLINDER HEAD......108
REMOVAL - RIGHT CYLINDER HEAD.....110
CLEANING...........................111
INSPECTION..........................111
INSTALLATION
INSTALLATION - LEFT CYLINDER HEAD . . . 112
INSTALLATION - RIGHT CYLINDER HEAD . 113
CAMSHAFT(S) - LEFT
DESCRIPTION........................114
REMOVAL............................115
INSTALLATION........................116
CAMSHAFT(S) - RIGHT
DESCRIPTION........................119
REMOVAL............................119
INSTALLATION........................120
CYLINDER HEAD COVER(S)
DESCRIPTION........................122REMOVAL
REMOVAL - RIGHT SIDE...............122
REMOVAL - LEFT SIDE................122
CLEANING...........................123
INSTALLATION
INSTALLATION - RIGHT SIDE...........123
INSTALLATIONÐLEFT SIDE............123
INTAKE/EXHAUST VALVES & SEATS
DESCRIPTION........................123
REMOVAL............................124
INSTALLATION........................124
ROCKER ARM / ADJUSTER ASSEMBLY
DESCRIPTION........................125
DIAGNOSIS AND TESTING - HYDRAULIC
LASH ADJUSTER.....................125
REMOVAL............................126
INSTALLATION........................126
VALVE SPRINGS
DESCRIPTION........................126
REMOVAL............................126
INSTALLATION........................127
VALVE STEM SEALS
DESCRIPTION........................127
ENGINE BLOCK
DESCRIPTION........................128
STANDARD PROCEDURE - CYLINDER BORE
HONING...........................128
CLEANING...........................128
INSPECTION.........................128
CONNECTING ROD BEARINGS
STANDARD PROCEDURE - CONNECTING
ROD BEARING FITTING...............129
CORE PLUGS
REMOVAL............................131
INSTALLATION........................131
CRANKSHAFT
DESCRIPTION........................131
REMOVAL............................131
INSPECTION.........................132
INSTALLATION........................132
CRANKSHAFT MAIN BEARINGS
STANDARD PROCEDUREÐCRANKSHAFT
MAIN BEARING - FITTING..............134
INSPECTION.........................135
CRANKSHAFT OIL SEAL - FRONT
REMOVAL............................135
INSTALLATION........................136
9 - 88 ENGINE - 4.7LDR

CRANKSHAFT OIL SEAL - REAR
DIAGNOSIS AND TESTING - REAR SEAL
AREA LEAKS........................137
REMOVAL............................137
INSTALLATION........................138
FLEX PLATE
REMOVAL............................138
INSTALLATION........................138
PISTON & CONNECTING ROD
DESCRIPTION........................139
STANDARD PROCEDURE - PISTON FITTING . 139
REMOVAL............................139
CLEANING...........................140
INSPECTION.........................140
INSTALLATION........................140
PISTON RINGS
STANDARD PROCEDURE - PISTON RING
FITTING............................142
VIBRATION DAMPER
REMOVAL............................144
INSTALLATION........................144
STRUCTURAL COVER
DESCRIPTION........................145
OPERATION..........................145
REMOVAL............................145
INSTALLATION........................145
FRONT MOUNT
REMOVAL............................146
INSTALLATION........................147
REAR MOUNT
REMOVAL............................149
INSTALLATION........................149
LUBRICATION
DESCRIPTION........................150
OPERATION..........................150
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - CHECKING
ENGINE OIL PRESSURE...............152
DIAGNOSIS AND TESTING - ENGINE OIL
LEAK..............................152
OIL
STANDARD PROCEDURE - ENGINE OIL
SERVICE...........................153
OIL FILTER
REMOVAL............................154
INSTALLATION........................155
OIL PAN
REMOVAL............................155
INSTALLATION........................155OIL PRESSURE SENSOR/SWITCH
DESCRIPTION
DESCRIPTION.......................156
DESCRIPTION.......................156
OPERATION
OPERATION........................156
OPERATION........................156
REMOVAL............................156
INSTALLATION........................156
OIL PUMP
REMOVAL............................156
DISASSEMBLY........................157
CLEANING...........................157
INSPECTION.........................157
ASSEMBLY...........................158
INSTALLATION........................159
INTAKE MANIFOLD
DESCRIPTION........................159
DIAGNOSIS AND TESTINGÐINTAKE
MANIFOLD LEAKAGE.................159
REMOVAL............................159
CLEANING...........................160
INSPECTION.........................160
INSTALLATION........................160
EXHAUST MANIFOLD
DESCRIPTION........................161
REMOVAL............................161
CLEANING...........................163
INSPECTION.........................163
INSTALLATION........................164
VALVE TIMING
DESCRIPTIONÐTIMING DRIVE SYSTEM....166
OPERATION - TIMING DRIVE SYSTEM.....166
STANDARD PROCEDURE
STANDARD PROCEDUREÐMEASURING
TIMING CHAIN WEAR.................167
STANDARD PROCEDURE - ENGINE TIMING
- VERIFICATION.....................167
TIMING BELT / CHAIN COVER(S)
REMOVAL............................170
INSTALLATION........................171
TIMING BELT/CHAIN AND SPROCKETS
REMOVAL............................172
INSPECTION.........................174
INSTALLATION........................176
IDLER SHAFT
REMOVAL............................179
INSTALLATION........................179
DRENGINE - 4.7L 9 - 89

ENGINE - 4.7L
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - PERFORMANCE
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 8 - ELECTRICAL/
STARTING - DIAGNOSIS AND
TESTING).
4. Faulty coil or control unit. 4. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL).
5. Incorrect spark plug gap. 5. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG
- CLEANING).
6. Dirt or water in fuel system. 6. Clean system and replace fuel
filter.
7. Faulty fuel pump, relay or wiring. 7. Repair or replace as necessary.
ENGINE STALLS OR ROUGH IDLE 1. Idle speed set to low. 1. (Refer to 14 - FUEL SYSTEM/
FUEL INJECTION/IDLE AIR
CONTROL MOTOR - REMOVAL).
2. Idle mixture too lean or too rich. 2. Refer to Powertrain Diagnosis
Information.
3. Vacuum leak. 3. Inspect intake manifold and
vacuum hoses, repair or replace as
necessary.
4. Faulty coil. 4. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL).
5. Incorrect engine timing. 5. (Refer to 9 - ENGINE/VALVE
TIMING - STANDARD
PROCEDURE).
9 - 90 ENGINE - 4.7LDR

CONDITION POSSIBLE CAUSE CORRECTION
1. ENGINE LOSS OF POWER 1. Dirty or incorrectly gapped spark
plugs.1. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG
- CLEANING).
2. Dirt or water in fuel system. 2. Clean system and replace fuel
filter.
3. Faulty fuel pump. 3. (Refer to 14 - FUEL SYSTEM/
FUEL DELIVERY/FUEL PUMP -
DIAGNOSIS AND TESTING).
4. Blown cylinder head gasket. 4. Replace cylinder head gasket.
5. Low compression. 5. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).
6. Burned, warped or pitted valves. 6. Replace as necessary.
7. Plugged or restricted exhaust
system.7. Inspect and replace as
necessary.
8. Faulty coil. 8. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL).
1. ENGINE MISSES ON
ACCELERATION1. Spark plugs dirty or incorrectly
gapped.1. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG
- CLEANING).
2. Dirt in fuel system. 2. Clean fuel system.
3. Burned, warped or pitted valves. 3. Replcae as necessary.
4. Faulty coil. 4. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL).
1. ENGINE MISSES AT HIGH
SPEED1. Spark plugs dirty or incorrectly
gapped.1. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG
- CLEANING).
2. Faulty coil. 2. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL).
3. Dirt or water in fuel system. 3. Clean system and replace fuel
filter.
DRENGINE - 4.7L 9 - 91
ENGINE - 4.7L (Continued)