1998 DODGE RAM 1500 clock

(2) Using a mirror, locate the TDC arrow on the
front cover (Fig. 96). Rotate the crankshaft until the
mark on the crankshaft damper is aligned with the
TDC arrow on the front cover. The engine is now at
TDC.
(3) Note the location of the V6 mark stamped into
the camshaft drive gears. If the V6 mark on each
camshaft drive gear is at the twelve o'clock position,
the engine is at TDC on the exhaust stroke. If the V6
mark on each gear is at the six o'clock position, the
engine is at TDC on the compression stroke. (Fig.
100)
(4) If both of the camshaft drive gears are off in
the same or opposite directions, the primary chain or
both secondary chains are at fault. Refer to Timing
Chain and Sprockets procedure in this section.
(5) If only one of the camshaft drive gears is off
and the other is correct, the problem is confined to
one secondary chain. Refer to Single camshaft tim-
ing, in this procedure.
(6) If both camshaft drive gear V6 marks are at
the twelve o'clock or the six o'clock position the
engine base timing is correct. Reinstall the cylinder
head covers.
COUNTER BALANCE SHAFT TIMING
(1) Ensure that the engine is at TDC with both
camshaft sprocket V6 marks in the 12 o'clock posi-
tion. (Fig. 100)(2) Look down the left cylinder head chain cavity.
The timing dot on the counter balance shaft drive
gear should be in the 6 o'clock position (Fig. 97).
TIMING - SINGLE CAMSHAFT
NOTE: to adjust the timing on one camshaft, pre-
form the following procedure.
(1) Using Chain Tensioner Wedge (Fig. 99), Special
Tool 8379, stabilize the secondary chain drive. For
reference purposes, mark the chain-to-sprocket posi-
tion. (Fig. 98)
(2) Remove the camshaft drive gear retaining bolt.
(3) Carefully remove the camshaft drive gear from
the camshaft.
(4) Re-index the camshaft drive gear in the chain
until the V6 mark is at the same position as the V6
mark on the opposite camshaft drive gear.
(5) Using Special Tool 8428 Camshaft Wrench,
rotate the camshaft until the alignment dowel on the
camshaft is aligned with the slot in the camshaft
drive gear.
CAUTION: Remove excess oil from camshaft
sprocket retaining bolt before reinstalling bolt. Fail-
ure to do so may cause over-torqueing of bolt
resulting in bolt failure.
Fig. 96 Engine Top Dead Center (TDC) Indicator
Mark
1 - TIMING CHAIN COVER
2 - CRANKSHAFT TIMING MARKS
Fig. 97 COUNTERBALANCE SHAFT ALIGNMENT
MARKS
1 - COUNTERBALANCE SHAFT GEAR
2 - TIMING MARK
3 - IDLER SPROCKET GEAR
9 - 78 ENGINE - 3.7LDR
VALVE TIMING (Continued)

TIMING BELT/CHAIN AND
SPROCKETS
REMOVAL
(1) Disconnect negative cable from battery.
(2) Drain cooling system(Refer to 7 - COOLING -
STANDARD PROCEDURE).
(3) Remove right and left cylinder head covers(Re-
fer to 9 - ENGINE/CYLINDER HEAD/CYLINDER
HEAD COVER(S) - REMOVAL).
(4) Remove radiator fan shroud(Refer to 7 - COOL-
ING/ENGINE/RADIATOR FAN - REMOVAL).
(5) Rotate engine until timing mark on crankshaft
damper aligns with TDC mark on timing chain cover
(Fig. 108) and the camshaft sprocket ªV6º marks are
at the 12 o'clock position (No. 1 TDC exhaust stroke)
(Fig. 107).
(6) Remove power steering pump(Refer to 19 -
STEERING/PUMP - REMOVAL).
Fig. 107 CAMSHAFT SPROCKET V6 MARKS, (#1 TDC EXHAUST STROKE)
1 - LEFT CYLINDER HEAD2 - RIGHT CYLINDER HEAD
Fig. 108 Engine Top Dead Center
1 - TIMING CHAIN COVER
2 - CRANKSHAFT TIMING MARKS
DRENGINE - 3.7L 9 - 83

(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)

REMOVAL
REMOVAL - LEFT CYLINDER HEAD
(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 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL).
(7) Remove the master cylinder and booster assem-
bly. Refer to section 5 brakes.
(8) Remove the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(9) Remove the fan shroud and fan blade assembly
(Refer to 7 - COOLING/ENGINE/FAN DRIVE VIS-
COUS CLUTCH - REMOVAL).
(10) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(11) Remove the power steering pump and set
aside.
(12) Rotate the crankshaft until the damper tim-
ing mark is aligned with TDC indicator mark (Fig.
9).(13) Verify the V8 mark on the camshaft sprocket
is at the 12 o'clock position (Fig. 11). Rotate the
crankshaft one turn if necessary.
(14) Remove the crankshaft damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
REMOVAL).
(15) Remove the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(16) Lock the secondary timing chains to the idler
sprocket using Special Tool 8515 (Fig. 10).
Fig. 9 Engine Top Dead Center (TDC) Indicator Mark
1 - TIMING CHAIN COVER
2 - CRANKSHAFT TIMING MARKS
Fig. 10 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 - 108 ENGINE - 4.7LDR
CYLINDER HEAD (Continued)

REMOVAL - RIGHT CYLINDER HEAD
(1) Disconnect battery negitive cable.
(2) Raise the vehicle on a hoist.
(3) Disconnect the exhaust pipe at the right side
exhaust manifold.
(4) Drain the engine coolant (Refer to 7 - COOL-
ING - STANDARD PROCEDURE).
(5) Lower the vehicle.
(6) Remove the intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL).
(7) Remove the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(8) Remove the fan shroud (Refer to 7 - COOLING/
ENGINE/FAN DRIVE VISCOUS CLUTCH -
REMOVAL).
(9) Remove oil fill housing from cylinder head.
(10) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(11) Rotate the crankshaft until the damper timing
mark is aligned with TDC indicator mark (Fig. 13).
(12) Verify the V8 mark on the camshaft sprocket
is at the 12 o'clock position (Fig. 14). Rotate the
crankshaft one turn if necessary.
(13) Remove the crankshaft damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
REMOVAL).(14) Remove the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
Fig. 13 Engine Top Dead Center (TDC) Indicator
Mark
1 - TIMING CHAIN COVER
2 - CRANKSHAFT TIMING MARKS
Fig. 14 Camshaft Sprocket V8 Marks
1 - LEFT CYLINDER HEAD2 - RIGHT CYLINDER HEAD
9 - 110 ENGINE - 4.7LDR
CYLINDER HEAD (Continued)

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.
REMOVAL
CAUTION: When the timing chain is removed and
the cylinder heads are still installed, DO NOT force-
fully rotate the camshafts or crankshaft indepen-
dently of each other. Severe valve and/or piston
damage can occur.
CAUTION: When removing the cam sprocket, timing
chains or camshaft, Failure to use Special Tool
8350 will result in hydraulic tensioner ratchet over
extension, requiring timing chain cover removal to
reset the tensioner ratchet.
(1) Remove cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(2) Set engine to TDC cylinder #1, camshaft
sprocket V8 marks at the 12 o'clock position.
(3) Mark one link on the secondary timing chain
on both sides of the V8 mark on the camshaft
sprocket to aid in installation.CAUTION: Do not hold or pry on the camshaft tar-
get wheel (Located on the right side camshaft
sprocket) for any reason, Severe damage will occur
to the target wheel resulting in a vehicle no start
condition.
(4) Loosen butDO NOTremove the camshaft
sprocket retaining bolt. Leave the bolt snug against
the sprocket.
NOTE: The timing chain tensioners must be
secured prior to removing the camshaft sprockets.
Failure to secure tensioners will allow the tension-
ers to extend, requiring timing chain cover removal
in order to reset tensioners.
CAUTION: Do not force wedge past the narrowest
point between the chain strands. Damage to the
tensioners may occur.
(5) Position Special Tool 8350 timing chain wedge
between the timing chain strands, tap the tool to
securely wedge the timing chain against the ten-
sioner arm and guide (Fig. 25).
NOTE: When gripping the camshaft, place the pliers
on the tube portion of the camshaft only. Do not
grip the lobes or the sprocket areas.
Fig. 25 Securing Timing Chain Tensioners Using Timing Chain Wedge
1 - LEFT CYLINDER HEAD
2 - RIGHT CYLINDER HEAD3 - SPECIAL TOOL 8350 WEDGE
4 - SPECIAL TOOL 8350 WEDGE
DRENGINE - 4.7L 9 - 115
CAMSHAFT(S) - LEFT (Continued)