1998 DODGE RAM 1500 Engine

ENGINE - 5.7L
TABLE OF CONTENTS
page page
ENGINE - 5.7L
DESCRIPTION........................182
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - INTRODUCTION..........183
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - PERFORMANCE..........183
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - MECHANICAL............185
DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE............186
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE.....186
DIAGNOSIS AND TESTINGÐENGINE
DIAGNOSIS - LUBRICATION............187
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - MECHANICAL............188
STANDARD PROCEDURE
STANDARD PROCEDURE - REPAIR
DAMAGED OR WORN THREADS........190
STANDARD PROCEDUREÐHYDROSTATIC
LOCK..............................190
REMOVAL............................190
INSTALLATION........................191
SPECIFICATIONS
5.7L ENGINE........................192
TORQUE...........................195
SPECIAL TOOLS
5.7L ENGINE........................196
AIR INTAKE SYSTEM
REMOVAL............................199
INSTALLATION........................199
CYLINDER HEAD
OPERATIONÐCYLINDER HEAD...........199
DIAGNOSIS AND TESTINGÐCYLINDER HEAD
GASKET FAILURE....................199
REMOVAL............................200
CLEANING...........................200
INSPECTION.........................200
INSTALLATION........................200
CYLINDER HEAD COVER(S)
REMOVAL............................201
INSTALLATION........................201
INTAKE/EXHAUST VALVES & SEATS
DESCRIPTION
DESCRIPTION - VALVE GUIDES.........202
DESCRIPTION.......................202
STANDARD PROCEDURE - REFACING.....202
REMOVAL............................203INSTALLATION........................203
ROCKER ARM / ADJUSTER ASSY
REMOVAL............................203
INSTALLATION........................203
VALVE STEM SEALS
DESCRIPTION........................203
VALVE SPRINGS
REMOVAL............................204
INSTALLATION........................204
ENGINE BLOCK
CLEANING...........................205
INSPECTION.........................205
CAMSHAFT & BEARINGS (IN BLOCK)
REMOVAL
REMOVAL - CAMSHAFT CORE HOLE PLUG. 205
REMOVAL - CAMSHAFT...............205
INSPECTION.........................206
INSTALLATION
INSTALLATION - CAMSHAFT CORE HOLE
PLUG..............................206
INSTALLATION - CAMSHAFT............206
CRANKSHAFT
REMOVAL............................206
INSTALLATION........................207
CRANKSHAFT MAIN BEARINGS
STANDARD PROCEDURE - CRANKSHAFT
MAIN BEARING - FITTING..............207
INSPECTION.........................208
CRANKSHAFT OIL SEAL - FRONT
REMOVAL............................208
INSTALLATION........................208
CRANKSHAFT OIL SEAL - REAR
DIAGNOSIS AND TESTING - REAR SEAL
AREA LEAKS........................209
REMOVAL............................209
INSTALLATION........................209
CRANKSHAFT REAR OIL SEAL RETAINER
REMOVAL............................209
INSTALLATION........................210
FLEX PLATE
REMOVAL............................210
INSTALLATION........................210
HYDRAULIC TAPPETS
DIAGNOSIS AND TESTING - HYDRAULIC
TAPPETS...........................210
REMOVAL............................211
INSTALLATION........................211
PISTON & CONNECTING ROD
DESCRIPTION........................211
9 - 180 ENGINE - 5.7LDR

STANDARD PROCEDUREÐPISTON FITTING . 211
REMOVAL............................212
CLEANING...........................212
INSPECTION.........................213
INSTALLATION........................213
PISTON RINGS
STANDARD PROCEDURE - PISTON RING
FITTING............................213
VIBRATION DAMPER
REMOVAL............................215
INSTALLATION........................215
STRUCTURAL COVER
DESCRIPTION........................216
OPERATION..........................216
REMOVAL............................216
INSTALLATION........................216
FRONT MOUNT
REMOVAL............................217
INSTALLATION........................218
REAR MOUNT
REMOVAL............................220
INSTALLATION........................220
LUBRICATION
DESCRIPTION........................220
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - CHECKING
ENGINE OIL PRESSURE...............220
DIAGNOSIS AND TESTING - ENGINE OIL
LEAK..............................220
OIL
STANDARD PROCEDURE - ENGINE OIL
SERVICE...........................222
OIL FILTER
REMOVAL............................223INSTALLATION........................223
OIL PAN
REMOVAL............................224
INSTALLATION........................224
OIL PUMP
REMOVAL............................224
CLEANING...........................224
INSPECTION.........................224
INSTALLATION........................225
INTAKE MANIFOLD
DESCRIPTION........................225
DIAGNOSIS AND TESTING - INTAKE
MANIFOLD LEAKAGE.................225
REMOVAL............................226
CLEANING...........................226
INSPECTION.........................226
INSTALLATION........................226
EXHAUST MANIFOLD
DESCRIPTION........................226
OPERATION..........................226
REMOVAL............................226
CLEANING...........................226
INSPECTION.........................227
INSTALLATION........................227
TIMING/CHAIN COVER
REMOVAL............................227
INSTALLATION........................227
TIMING/CHAIN AND SPROCKETS
REMOVAL............................228
INSTALLATION........................228
TIMING CHAIN/TENSIONER
DESCRIPTION........................229
OPERATION..........................229
DRENGINE - 5.7L 9 - 181

ENGINE - 5.7L
DESCRIPTION
The 5.7L engine (Fig. 1)(345 CID) eight-cylinder
engine is a 90É V-Type lightweight, deep skirt cast
iron block, aluminum heads, single cam, overhead
valve engine with hydraulic roller tappets. The heads
incorporate splayed valves with a hemispherical style
combustion chamber and dual spark plugs. The cyl-
inders 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 5.7L ENGINE
9 - 182 ENGINE - 5.7LDR

DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - INTRODUCTION
Engine diagnosis is helpful in determining the
causes of malfunctions not detected and remedied by
routine maintenance.
These malfunctions may be classified as either per-
formance (e.g., engine idles rough and stalls) or
mechanical (e.g., a strange noise).
(Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING) - PERFORMANCE and (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)ÐMECHANICAL for
possible causes and corrections of malfunctions.
(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY -
DIAGNOSIS AND TESTING) and (Refer to 14 -
FUEL SYSTEM/FUEL INJECTION - DIAGNOSIS
AND TESTING) for the fuel system diagnosis.Additional tests and diagnostic procedures may be
necessary for specific engine malfunctions that can
not be isolated with the Service Diagnosis charts.
Information concerning additional tests and diagno-
sis is provided within the following diagnosis:
²Cylinder Compression Pressure Test (Refer to 9 -
ENGINE - DIAGNOSIS AND TESTING).
²Cylinder Combustion Pressure Leakage Test
(Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING).
²Engine Cylinder Head Gasket Failure Diagnosis
(Refer to 9 - ENGINE/CYLINDER HEAD - DIAGNO-
SIS AND TESTING).
²Intake Manifold Leakage Diagnosis (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
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.
DRENGINE - 5.7L 9 - 183
ENGINE - 5.7L (Continued)

CONDITION POSSIBLE CAUSE CORRECTION
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).
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 SPEED 1. 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.
9 - 184 ENGINE - 5.7LDR
ENGINE - 5.7L (Continued)

DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - MECHANICAL
CONDITION POSSIBLE CAUSES CORRECTIONS
NOISY VALVES 1. High or low oil level in
crankcase.1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Thin or diluted oil. 2. Change oil and filter.
3. Low oil pressure. 3. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
4. Dirt in lash adjusters. 4. Replace as necessary.
5. Worn rocker arms. 5. Replace as necessary.
6. Worn lash adjusters 6. Replace as necessary.
7. Worn valve guides. 7. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE)
8. Excessive runout of valve seats
on valve faces.8. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE)
CONNECTING ROD NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Connecting rod journal
out-of-round.5. Service or replace crankshaft.
6. Misaligned connecting rods. 6. Replace bent connecting rods.
MAIN BEARING NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Excessive end play. 5. Check thrust washers for wear.
6. Crankshaft journal out-of round. 6. Service or replace crankshaft.
7. Loose flywheel or torque
converter.7. Tighten to correct torque
DRENGINE - 5.7L 9 - 185
ENGINE - 5.7L (Continued)

DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE
The results of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise the indicated compression pressures may
not be valid for diagnosis purposes.
(1) Clean the spark plug recesses with compressed
air.
(2) Remove the spark plugs.
(3) Disable the fuel system (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY - DESCRIPTION).
(4) Remove the ASD relay (Refer to 8 - ELECTRI-
CAL/IGNITION CONTROL/AUTO SHUT DOWN
RELAY - REMOVAL).
(5) Insert a compression pressure gauge and rotate
the engine with the engine starter motor for three
revolutions.
(6) Record the compression pressure on the 3rd
revolution. Continue the test for the remaining cylin-
ders.
(7) (Refer to 9 - ENGINE - SPECIFICATIONS) for
the correct engine compression pressures.
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
²Exhaust and intake valve leaks (improper seat-
ing).²Leaks between adjacent cylinders or into water
jacket.
²Any causes for combustion/compression pressure
loss.
(1) Check the coolant level and fill as required. DO
NOT install the radiator cap.
(2) Start and operate the engine until it attains
normal operating temperature, then turn the engine
OFF.
(3) Remove the spark plugs.
(4) Remove the oil filler cap.
(5) Remove the air cleaner hose.
(6) Calibrate the tester according to the manufac-
turer's instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1,379
kPa (200 psi) maximum and 552 kPa (80 psi) recom-
mended.
(7) Perform the test procedures on each cylinder
according to the tester manufacturer's instructions.
Set piston of cylinder to be tested at TDC compres-
sion,While testing, listen for pressurized air escaping
through the throttle body, tailpipe and oil filler cap
opening. Check for bubbles in the radiator coolant.
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 CYLINDER COMBUSTION PRESSURE
LEAKAGE DIAGNOSIS CHART.
CYLINDER COMBUSTION PRESSURE LEAKAGE DIAGNOSIS CHART
CONDITION POSSIBLE CAUSE CORRECTION
AIR ESCAPES THROUGH
THROTTLE BODYIntake valve bent, burnt, or not
seated properlyInspect valve and valve seat. Reface
or replace, as necessary. Inspect
valve springs. Replace as necessary.
AIR ESCAPES THROUGH TAILPIPE Exhaust valve bent, burnt, or not
seated properlyInspect valve and valve seat. Reface
or replace, as necessary. Inspect
valve springs. Replace as necessary.
AIR ESCAPES THROUGH
RADIATORHead gasket leaking or cracked
cylinder head or blockRemove cylinder head and inspect.
Replace defective part
MORE THAN 50% LEAKAGE FROM
ADJACENT CYLINDERSHead gasket leaking or crack in
cylinder head or block between
adjacent cylindersRemove cylinder head and inspect.
Replace gasket, head, or block as
necessary
MORE THAN 25% LEAKAGE AND
AIR ESCAPES THROUGH OIL
FILLER CAP OPENING ONLYStuck or broken piston rings; cracked
piston; worn rings and/or cylinder wallInspect for broken rings or piston.
Measure ring gap and cylinder
diameter, taper and out-of-round.
Replace defective part as necessary
9 - 186 ENGINE - 5.7LDR
ENGINE - 5.7L (Continued)

DIAGNOSIS AND TESTINGÐENGINE DIAGNOSIS - LUBRICATION
CONDITION POSSIBLE CAUSES CORRECTION
OIL LEAKS 1. Gaskets and O-Rings. 1.
(a) Misaligned or damaged. (a) Replace as necessary.
(b) Loose fasteners, broken or
porous metal parts.(b) Tighten fasteners, Repair or
replace metal parts.
2. Crankshaft rear seal 2. Replace as necessary.
3. Crankshaft seal flange.
Scratched, nicked or grooved.3. Polish or replace crankshaft.
4. Oil pan flange cracked. 4. Replace oil pan.
5.Front cover seal, damaged or
misaligned.5. Replace seal.
6. Scratched or damaged vibration
damper hub.6. Polish or replace damper.
7. Crankshaft Rear Flange
Microporosity7. Replace Crankshaft
OIL PRESSURE DROP 1. Low oil level. 1. Check and correct oil level.
2. Faulty oil pressure sending unit. 2. Replace sending unit.
3. Low oil pressure. 3. Check pump and bearing
clearance.
4. Clogged oil filter. 4. Replace oil filter.
5. Worn oil pump. 5. Replace as necessary.
6. Thin or diluted oil. 6. Change oil and filter.
7. Excessive bearing clearance. 7. Replace as necessary.
8. Oil pump relief valve stuck. 8. Replace oil pump.
9. Oil pickup tube loose or
damaged.9. Replace as necessary.
OIL PUMPING AT RINGS; SPARK
PLUGS FOULING1. Worn or damaged rings. 1. Hone cylinder bores and replace
rings.
2. Carbon in oil ring slots. 2. Replace rings.
3. Incorrect ring size installed. 3. Replace rings.
4. Worn valve guides. 4. Ream guides and replace valves.
5. Leaking intake gasket. 5. Replace intake gaskets.
6. Leaking valve guide seals. 6. Replace valve guide seals.
DRENGINE - 5.7L 9 - 187
ENGINE - 5.7L (Continued)