1998 DODGE RAM 1500 Drive belt removal

CRANKSHAFT OIL SEAL - FRONT
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(3) Remove A/C compressor mouning fasteners and
set aside.
(4) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(5) Remove upper radiator hose.
(6) Disconnect electrical connector for fan mounted
inside radiator shroud.
(7) Remove radiator shroud attaching fasteners.
NOTE: Transmission cooler line snaps into shroud
lower right hand corner.
(8)
Remove radiator cooling fan and shroud (Refer to
7 - COOLING/ENGINE/RADIATOR FAN - REMOVAL).
(9) Remove crankshaft damper bolt.
(10) Remove damper using Special Tools 8513
Insert and 1026 Three Jaw Puller (Fig. 37).
(11) Using Special Tool 8511, remove crankshaft
front seal (Fig. 38).
INSTALLATION
CAUTION: To prevent severe damage to the Crank-
shaft, Damper or Special Tool 8512, thoroughlyclean the damper bore and the crankshaft nose
before installing Damper.
(1) Using Special Tool 8348 and 8512, install
crankshaft front seal (Fig. 39).
(2) Install vibration damper (Refer to 9 - ENGINE/
ENGINE BLOCK/VIBRATION DAMPER - INSTAL-
LATION).
Fig. 37 Crankshaft Damper Removal
1 - SPECIAL TOOL 8513 INSERT
2 - SPECIAL TOOL 1026
Fig. 39 Crankshaft Front Seal Installation
1 - TIMING CHAIN COVER
2 - SPECIAL TOOL 8348
3 - SPECIAL TOOL 8512
Fig. 38 Crankshaft Front Seal Removal
1 - SPECIAL TOOL 8511
9 - 46 ENGINE - 3.7LDR

(3) Install radiator cooling fan and shroud (Refer
to 7 - COOLING/ENGINE/RADIATOR FAN -
INSTALLATION).
(4) Install upper radiator hose.
(5) Install A/C compressor and tighten fasteners to
54 N´m (40 ft. lbs.).
(6) Install accessory drive belt refer (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(7) Refill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(8) Connect negative cable to battery.
CRANKSHAFT OIL SEAL -
REAR
REMOVAL
NOTE: This procedure can be performed in vehicle.
(1) If being preformed in vehicle, remove the
transmission.
(2) Remove the flexplate (Refer to 9 - ENGINE/
ENGINE BLOCK/FLEX PLATE - REMOVAL).
NOTE: The crankshaft oil seal CAN NOT be reused
after removal.
NOTE: The crankshaft rear oil seal remover Special
Tool 8506 must be installed deeply into the seal.
Continue to tighten the removal tool into the seal
until the tool can not be turned farther. Failure to
install tool correctly the first time will cause tool to
pull free of seal without removing seal from engine.
(3) Using Special Tool 8506 (Fig. 40), remove the
crankshaft rear oil seal.
INSTALLATION
(1) Lubricate the crankshaft flange with engine oil.
(2) Position the magnetic seal guide Special Tool
8349-2 (Fig. 41) onto the crankshaft rear face. Then
position the crankshaft rear oil seal onto the guide.
Fig. 40 Crankshaft Rear Oil Seal Removal
1 - REAR CRANKSHAFT SEAL
2 - SPECIAL TOOL 8506
Fig. 41 Crankshaft Rear Oil Seal Guide Special Tool
8349-2 and Oil
1 - REAR CRANKSHAFT SEAL
2 - SPECIAL TOOL 8349-2 GUIDE
DRENGINE - 3.7L 9 - 47
CRANKSHAFT OIL SEAL - FRONT (Continued)

(8) Install the oil ring expander.
(9) Install upper side rail (Fig. 57) by placing one
end between the piston ring groove and the expander
ring. Hold end firmly and press down the portion to
be installed until side rail is in position. Repeat this
step for the lower side rail.
(10) Install No. 2 intermediate piston ring using a
piston ring installer (Fig. 58).
(11) Install No. 1 upper piston ring using a piston
ring installer (Fig. 58).
(12) Position piston ring end gaps as shown in
(Fig. 59). It is important that expander ring gap is at
least 45É from the side rail gaps, but not on the pis-
ton pin center or on the thrust direction.
VIBRATION DAMPER
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).(3) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(4) Remove radiator upper hose.
(5) Remove upper fan shroud.
(6) Using Special Tools 6958 Spanner with Adapter
Pins 8346, loosen fan and viscous assembly from
water pump (Fig. 60).
(7) Remove fan and viscous assembly.
Fig. 57 Side Rail - Installation
1 - SIDE RAIL END
Fig. 58 Upper and Intermediate Rings - Installation
Fig. 59 Piston Ring End Gap Position
1 - SIDE RAIL UPPER
2 - NO. 1 RING GAP
3 - PISTON PIN
4 - SIDE RAIL LOWER
5 - NO. 2 RING GAP AND SPACER EXPANDER GAP
Fig. 60 FAN ASSEMBLY - REMOVAL/ASSEMBLY
1 - SPECIAL TOOL 6958 SPANNER WRENCH WITH ADAPTER
PINS 8346
2-FAN
DRENGINE - 3.7L 9 - 55
PISTON RINGS (Continued)

(5) Install fan blade assembly (Refer to 7 - COOL-
ING/ENGINE/FAN DRIVE VISCOUS CLUTCH -
INSTALLATION).
(6) Install radiator upper shroud and tighten fas-
teners to 11 N´m (95 in. lbs.).
(7) Connect electrical connector for shroud fan.
(8) Install radiator upper hose.
(9) Install accessory drive belt (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/DRIVE BELTS - INSTAL-
LATION).
(10) Refill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(11) Connect negative cable to battery.
STRUCTURAL COVER
DESCRIPTION
The structural dust cover is made of die cast alu-
minum and joins the lower half of the transmission
bell housing to the engine bedplate.
OPERATION
The structural cover provides additional power-
train stiffness and reduces noise and vibration.
REMOVAL
(1) Raise vehicle on hoist.
(2) Remove the left hand exhaust pipe from
exhaust manifold.
(3) Loosen the right hand exhaust manifold-to-ex-
haust pipe retaining bolts.
(4) Remove the eight bolts retaining structural
cover (Fig. 64) in the sequence shown.
(5) Pivot the exhaust pipe downward and remove
the structural cover.
INSTALLATION
CAUTION: The structural cover must be installed as
described in the following steps. Failure to do so
will cause severe damage to the cover.
(1) Position the structural cover in the vehicle.
(2) Install all four bolts retaining the cover-to-en-
gine. DO NOT tighten the bolts at this time.
(3) Install the four cover-to-transmission bolts. Do
NOT tighten at this time.
CAUTION: The structural cover must be held tightly
against both the engine and the transmission bell
housing during tightening sequence. Failure to do
so may cause damage to the cover.(4) Starting with the two rear cover-to-engine
bolts, tighten bolts (1) (Fig. 65) to 54 N´m (40 ft. lbs.),
then tighten bolts (2) (Fig. 65) and (3) to 54 N´m ( 40
ft. lbs.) in the sequence shown.
(5) Install the exhaust pipe on left hand exhaust
manifold.
(6) Tighten exhaust manifold-to-exhaust pipe
retaining bolts to 20±26 N´m (15±20 ft. lbs.).
Fig. 64 Structural Cover
1 - BOLT
2 - BOLT
3 - BOLT
Fig. 65 Structural Cover
1 - BOLT
2 - BOLT
3 - BOLT
DRENGINE - 3.7L 9 - 57
VIBRATION DAMPER (Continued)

(3) Remove the timing chains and tensioners
(Refer to 9 - ENGINE/VALVE TIMING/TIMING
BELT/CHAIN AND SPROCKETS - REMOVAL).
(4) Remove the four bolts, primary timing chain
tensioner and the oil pump.
DISASSEMBLY
(1) Remove oil pump cover screws and lift off cover
plate.
(2) Remove pump inner and outer rotors.
NOTE: Once the oil pressure relief valve, cup plug,
and pin are removed, the pump assembly must be
replaced.
(3) If it is necessary to remove the pressure relief
valve, drive the roll pin from pump housing and
remove cup plug, spring and valve.
INSPECTION
CAUTION: Oil pump pressure relief valve and spring
should not be removed from the oil pump. If these com-
ponents are disassembled and or removed from the
pump the entire oil pump assembly must be replaced.
(1) Clean all parts thoroughly. Mating surface of
the oil pump housing should be smooth. If the pump
cover is scratched or grooved the oil pump assembly
should be replaced.
(2) Lay a straight edge across the pump cover sur-
face (Fig. 76). If a 0.025 mm (0.001 in.) feeler gauge
can be inserted between the cover and the straight
edge the oil pump assembly should be replaced.(3) Measure the thickness of the outer rotor (Fig.
77). If the outer rotor thickness measures at 12.005
mm (0.472 in.) or less the oil pump assembly must be
replaced.
(4) Measure the diameter of the outer rotor. If the
outer rotor diameter measures at 85.925 mm (3.382
in.) or less the oil pump assembly must be replaced.
(5) Measure the thickness of the inner rotor (Fig.
78). If the inner rotor thickness measures at 12.005
mm (0.472 in.) or less then the oil pump assembly
must be replaced.
Fig. 76 Checking Oil Pump Cover Flatness
1 - STRAIGHT EDGE
2 - FEELER GAUGE
3 - OIL PUMP COVER
Fig. 77 Measuring Outer Rotor Thickness
Fig. 78 Measuring Inner Rotor Thickness
9 - 68 ENGINE - 3.7LDR
OIL PUMP (Continued)

block. A large washer on the idler shaft bolt and the
rear flange of the idler shaft are used to control
sprocket thrust movement. Pressurized oil is routed
through the center of the idler shaft to provide lubri-
cation for the two bushings used in the idler sprocket
assembly.
There are two secondary drive chains, both are
roller 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 26 tooth cam sprocket directly from
the 26 tooth sprocket on the idler sprocket assembly.
A fixed chain guide and a hydraulic oil damped ten-
sioner are used to maintain tension in each second-
ary chain system. The hydraulic tensioners for the
secondary chain systems are fed pressurized oil from
oil reservoir pockets in the block. Each tensioner
incorporates a controlled leak path through a device
known as a vent disc located in the nose of the piston
to manage chain loads. 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 friction and long wear. The
secondary timing chains receive lubrication from a
small orifice in the tensioners. This orifice is pro-
tected from clogging by a fine mesh screen which is
located on the back of the hydraulic tensioners.
STANDARD PROCEDURE
MEASURING TIMING CHAIN WEAR
NOTE: This procedure must be performed with the
timing chain cover removed.
(1) Remove the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT/CHAIN
AND SPROCKETS - REMOVAL).
(2) To determine if the secondary timing chains
are worn, rotate the engine clockwise until maximum
tensioner piston extension is obtained. Measure the
distance between the secondary timing chain ten-
sioner housing and the step ledge on the piston. The
measurement at point (A) must be less than 15mm
(.5906 inches) (Fig. 95).
(3) If the measurement exceeds the specification
the secondary timing chains are worn and require
replacement (Refer to 9 - ENGINE/VALVE TIMING/
TIMING BELT/CHAIN AND SPROCKETS -
REMOVAL).
SERVICE PROCEDURE - TIMING VERIFICATION
CAUTION: The 3.7L is a non free-wheeling design
engine. Therefore, correct engine timing is critical.
NOTE: Components referred to as left hand or right
hand are as viewed from the drivers position inside
the vehicle.
NOTE: The blue link plates on the chains and the
dots on the camshaft drive sprockets may not line
up during the timing verification procedure. The
blue link plates are lined up with the sprocket dots
only when re-timing the complete timing drive.
Once the timing drive is rotated blue link-to-dot
alignment is no longer valid.
Engine base timing can be verified by the following
procedure:
(1) Remove the cylinder head covers. Refer to the
procedure in this section.
Fig. 95 Measuring Secondary Timing Chains For
Wear
1 - SECONDARY TENSIONER ARM
2 - SECONDARY CHAIN TENSIONER PISTON
DRENGINE - 3.7L 9 - 77
VALVE TIMING (Continued)

IDLER SHAFT
REMOVAL
(1) Remove the primary and secondary timing
chains and sprockets. Refer to procedure in this sec-
tion.
NOTE: To remove the idler shaft, it is necessary to
tap threads into the shaft, to install the removal
tool.
(2) Using a 12 mm X 1.75 tap, cut threads in the
idler shaft center bore.
(3) Cover the radiator core with a suitable cover.
CAUTION: Use care when removing the idler shaft,
Do not strike the radiator cooling fins with the slide
hammer.
(4) Using Special Tool 8517 Slide Hammer, remove
the idler shaft.
INSTALLATION
(1) Thoroughly clean the idler shaft bore.
(2) Position the idler shaft in the bore.
NOTE: The two lubrication holes in the idler shaft
do not require any special alignment.
NOTE: Before using the retaining bolt to install the
idler shaft, coat the threads and the pilot on the
idler shaft, with clean engine oil.
(3) Using the primary idler sprocket retaining bolt
and washer, carefully draw the idler shaft into the
bore until fully seated.
(4) Coat the idler shaft with clean engine oil.
(5) Install the timing chains and sprockets. Refer
to procedure in this section.
TIMING BELT / CHAIN
COVER(S)
REMOVAL
(1) Disconnect the battery negative cable.
(2) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(3) Remove electric cooling fan and fan shroud
assembly.
(4) Remove fan and fan drive assembly (Refer to 7
- COOLING/ENGINE/FAN DRIVE VISCOUS
CLUTCH - REMOVAL).
(5) Disconnect both heater hoses at timing cover.
(6) Disconnect lower radiator hose at engine.(7) Remove accessory drive belt tensioner assembly
(Fig. 103).
(8) Remove crankshaft damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
REMOVAL).
(9) Remove the generator (Refer to 8 - ELECTRI-
CAL/CHARGING/GENERATOR - REMOVAL).
(10) Remove A/C compressor (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING/A/C COM-
PRESSOR - REMOVAL).
CAUTION: The 3.7L engine uses an anerobic sealer
instead of a gasket to seal the front cover to the
engine block, from the factory. For service, MoparT
Engine RTV sealant must be substituted.
NOTE: It is not necessary to remove the water
pump for timing cover removal.
(11) Remove the bolts holding the timing cover to
engine block (Fig. 104).
(12) Remove the timing cover.
INSTALLATION
CAUTION: Do not use oil based liquids to clean tim-
ing cover or block surfaces. Use only rubbing alco-
hol, along with plastic or wooden scrapers. Use no
wire brushes or abrasive wheels or metal scrapers,
or damage to surfaces could result.
Fig. 103 ACCESSORY DRIVE BELT TENSIONER
1 - TENSIONER ASSEMBLY
2 - FASTENER TENSIONER TO FRONT COVER
DRENGINE - 3.7L 9 - 81

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