Downloaded from www.Manualslib.com manuals search engine (6) To align the bearing cap, use cap slot, align-
ment dowel and cap bolts. DO NOT remove excess
material after assembly. DO NOT strike rear cap
more than 2 times for proper engagement.
(7) Install the rear main bearing cap with cleaned
and oiled cap bolts. Alternately tighten ALL cap bolts
to 115 N´m (85 ft. lbs.) torque.
(8) Install oil pump.
(9) Apply MopartSilicone Rubber Adhesive Seal-
ant, or equivalent, at bearing cap to block joint to
provide cap to block and oil pan sealing (Fig. 72).
Apply enough sealant until a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(10) Immediately install the oil pan.
LOWER SEAL
REMOVAL
(1) Remove the oil pan.
(2) Remove the oil pump from the rear main bear-
ing cap.
(3) Remove the rear main bearing cap and discard
the old lower seal.
INSTALLATION
(1) Clean the rear main cap mating surfaces
including the oil pan gasket groove.
(2) Carefully install a new upper seal (refer to
Upper Seal Replacement - Crankshaft Installed pro-
cedure above).
(3) Lightly oil the new lower seal lips with engine
oil.
(4) Install a new lower seal in bearing cap with
the white paint facing the rear of engine.
(5) Apply 5 mm (0.20 in) drop of MopartGasket
Maker, or equivalent, on each side of the rear main
bearing cap (Fig. 71). DO NOT over apply sealant or
allow the sealant to contact the rubber seal. Assem-
ble bearing cap to cylinder block immediately after
sealant application.
(6) To align the bearing cap, use cap slot, align-
ment dowel and cap bolts. DO NOT remove excess
material after assembly. DO NOT strike rear cap
more than 2 times for proper engagement.
(7) Install the rear main bearing cap with cleaned
and oiled cap bolts. Alternately tighten the cap bolts
to 115 N´m (85 ft. lbs.) torque.
(8) Install oil pump.
(9) Apply MopartSilicone Rubber Adhesive Seal-
ant, or equivalent, at bearing cap to block joint to
provide cap to block and oil pan sealing (Fig. 72).
Apply enough sealant until a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(10) Immediately install the oil pan.
ENGINE CORE OIL AND CAMSHAFT PLUGS
Engine core plugs have been pressed into the oil
galleries behind the camshaft thrust plate (Fig. 73).
This will reduce internal leakage and help maintain
higher oil pressure at idle.
REMOVAL
(1) Using a blunt tool such as a drift or a screw-
driver and a hammer, strike the bottom edge of the
cup plug (Fig. 74).
(2) With the cup plug rotated, grasp firmly with
pliers or other suitable tool and remove plug (Fig.
74).
INSTALLATION
Thoroughly clean inside of cup plug hole in cylin-
der block or head. Be sure to remove old sealer.
Be certain the new plug is cleaned of all oil or
grease.
(1) Coat edges of plug and core hole with Mopart
Gasket Maker, or equivalent.
CAUTION: DO NOT drive cup plug into the casting,
as restricted coolant flow can result and cause seri-
ous engine problems.
(2) Using proper plug drive, drive cup plug into
hole. The sharp edge of the plug should be at least
0.50 mm (0.020 in.) inside the lead-in chamfer.
(3) It is not necessary to wait for curing of the
sealant. The cooling system can be filled and the
vehicle placed in service immediately.
Fig. 73 Location of Cup Plugs in Oil Galleries
1 ± CUP PLUGS
9 - 120 5.2L ENGINEDN
REMOVAL AND INSTALLATION (Continued)
Downloaded from www.Manualslib.com manuals search engine (2) Measure the concentricity of valve seat using a
dial indicator. Total runout should not exceed 0.051
mm (0.002 inch) total indicator reading.
(3) Inspect the valve seat with Prussian blue to
determine where the valve contacts the seat. To do
this, coat valve seat LIGHTLY with Prussian blue
then set valve in place. Rotate the valve with light
pressure. If the blue is transferred to the center of
valve face, contact is satisfactory. If the blue is trans-
ferred to the top edge of valve face, lower valve seat
with a 15É stone. If the blue is transferred to bottom
edge of valve face raise valve seat with a 60É stone.
(4) When seat is properly positioned the width of
intake seats should be 1.016-1.524 mm (0.040-0.060
inch). The width of the exhaust seats should be
1.524-2.032 mm (0.060-0.080 inch).
VALVE SPRING INSPECTION
Whenever valves have been removed for inspection,
reconditioning or replacement, valve springs should
be tested. As an example the compression length of
the spring to be tested is 1-5/16 inch. Turn table of
Universals Valve Spring Tester Tool until surface is
in line with the 1-5/16 inch mark on the threaded
stud. Be sure the zero mark is to the front (Fig. 80).
Place spring over stud on the table and lift compress-
ing lever to set tone device. Pull on torque wrench
until ping is heard. Take reading on torque wrench
at this instant. Multiply this reading by 2. This will
give the spring load at test length. Fractional mea-
surements are indicated on the table for finer adjust-
ments. Refer to specifications to obtain specified
height and allowable tensions. Discard the springs
that do not meet specifications.
OIL PUMP
DISASSEMBLE
(1) Remove the relief valve as follows:
(a) Remove cotter pin. Drill a 3.175 mm (1/8
inch) hole into the relief valve retainer cap and
insert a self-threading sheet metal screw.
(b) Clamp screw into a vise and while support-
ing oil pump, remove cap by tapping pump body
using a soft hammer. Discard retainer cap and
remove spring and relief valve (Fig. 81).
(2) Remove oil pump cover (Fig. 82).
(3) Remove pump outer rotor and inner rotor with
shaft (Fig. 82).
(4) Wash all parts in a suitable solvent and inspect
carefully for damage or wear.
ASSEMBLE
(1) Install pump rotors and shaft, using new parts
as required.
(2) Position the oil pump cover onto the pump
body. Tighten cover bolts to 11 N´m (95 in. lbs.)
torque.
(3) Install the relief valve and spring. Insert the
cotter pin.
(4) Tap on a new retainer cap.
(5) Prime oil pump before installation by filling
rotor cavity with engine oil.
Fig. 80 Testing Valve Spring for Compressed
Length
1 ± TORQUE WRENCH
2 ± VALVE SPRING TESTER
Fig. 81 Oil Pressure Relief Valve
1 ± OIL PUMP ASSEMBLY
2 ± COTTER PIN
3 ± RELIEF VALVE
4 ± RETAINER CAP
5 ± SPRING
DN5.2L ENGINE 9 - 123
DISASSEMBLY AND ASSEMBLY (Continued)
Downloaded from www.Manualslib.com manuals search engine If oil pressure was low and pump is within specifi-
cations, inspect for worn engine bearings or other
reasons for oil pressure loss.
CYLINDER BLOCK
CLEANING
Clean cylinder block thoroughly and check all core
hole plugs for evidence of leaking.
INSPECTION
Examine block for cracks or fractures.
The cylinder walls should be checked for out-of-
round and taper with Cylinder Bore Indicator Tool
C-119. The cylinder block should be bored and honed
with new pistons and rings fitted if:
²The cylinder bores show more than 0.127 mm
(0.005 inch) out-of-round.²The cylinder bores show a taper of more than
0.254 mm (0.010 inch).
²The cylinder walls are badly scuffed or scored.
Boring and honing operation should be closely coor-
dinated with the fitting of pistons and rings so spec-
ified clearances may be maintained.
Refer to Standard Service Procedures in the begin-
ning of this Group for the proper honing of cylinder
bores.
INTAKE MANIFOLD
CLEANING
Clean manifold in solvent and blow dry with com-
pressed air.
Clean cylinder block front and rear gasket surfaces
using a suitable solvent.
The plenum pan rail must be clean and dry (free of
all foreign material).
INSPECTION
Inspect manifold for cracks.
Inspect mating surfaces of manifold for flatness
with a straightedge.
EXHAUST MANIFOLD
CLEANING
Clean mating surfaces on cylinder head and mani-
fold, wash with solvent and blow dry with com-
pressed air.
INSPECTION
Inspect manifold for cracks, Inspect mating sur-
faces of manifold for flatness with a straight edge.
Seal surfaces must be flat within 0.1 mm (0.004 inch)
overall.
Fig. 90 Proper Installation of Retainer Cap
1 ± RETAINER CAP
2 ± CHAMFER
3 ± COTTER KEY
DN5.2L ENGINE 9 - 127
CLEANING AND INSPECTION (Continued)
Downloaded from www.Manualslib.com manuals search engine EXHAUST MANIFOLD
DESCRIPTION
The exhaust manifolds are constructed of cast iron
and are LOG type with balanced flow (Fig. 5). One
exhaust manifold is attached to each cylinder head.
OPERATION
The exhaust manifolds collect the engine exhaust
exiting the combustion chambers, then channels the
exhaust gases to the exhaust pipes attached to the
manifolds.
INTAKE MANIFOLD
DESCRIPTION
The aluminum intake manifold (Fig. 6) is a single
plane design with equal length runners and uses a
separate plenum, therefore the manifold does have a
plenum gasket. It also uses separate flange gaskets
and front and rear cross-over gaskets. Extreme caremust be used when sealing the gaskets to ensure
that excess sealant does not enter the intake runners
causing a restriction. Whenever the intake manifold
is removed inspect the plenum pan for evidence of
excess oil buildup, this condition indicates that the
plenum pan gasket is leaking.
OPERATION
The intake manifold, meters and delivers air to the
combustion chambers allowing the fuel delivered by
the fuel injectors to ignite, thus producing power.
1 ± OIL DEFLECTOR TAB
2 ± BOLT
3 ± ROCKER ARM PIVOT
4 ± ROCKER ARM
5 ± DRIP OILING FOR VALVE TIP
6 ± CYLINDER HEAD BOSS
7 ± TO MAIN BEARINGS
8 ± TO CAMSHAFT BEARINGS
9 ± ROCKER ARM
10 ± HOLLOW PUSH ROD
11 ± TAPPET
12 ± TO CONNECTING ROD BEARINGS
13 ± OIL INTAKE14 ± OIL PUMP
15 ± OIL FILTER
16 ± CRANKSHAFT
17 ± FROM OIL PUMP
18 ± OIL TO FILTER
19 ± OIL FROM FILTER TO SYSTEM
20 ± PASSAGE TO CAMSHAFT REAR BEARING
21 ± RIGHT OIL GALLERY
22 ± PLUG
23 ± OIL PASSAGE FOR OIL PRESSURE INDICATOR LIGHT
24 ± OIL SUPPLY VIA HOLLOW PUSH ROD SUPPLY IS FROM
OIL GALLERY METERED THROUGH HYDRAULIC TAPPET
25 ± OIL SUPPLY FROM HOLLOW PUSH ROD
Fig. 5 Exhaust ManifoldsÐV-8 Gas Engines Typical
1 ± EXHAUST MANIFOLD (LEFT)
2 ± BOLTS & WASHERS
3 ± NUTS & WASHERS
4 ± EXHAUST MANIFOLD (RIGHT)
5 ± BOLTS & WASHERS
Fig. 6 Intake Manifold and Throttle BodyÐV-8 Gas
Engines Typical
1 ± FUEL RAIL ASSEMBLY
2 ± FUEL RAIL MOUNTING BOLTS
3 ± FUEL RAIL CONNECTING HOSES
DN5.9L ENGINE 9 - 139
DESCRIPTION AND OPERATION (Continued)
Downloaded from www.Manualslib.com manuals search engine CRANKSHAFT MAIN BEARINGS
DESCRIPTION
Main bearings are located in the cylinder block.
One half of the main bearing is located in the crank-
shaft main bore the other half of the matching bear-
ing is located in the main bearing cap (Fig. 9). There
are five main bearings. Number three main bearing
is flanged, this flange controls crankshaft thrust.
OPERATION
The main bearings encircle the crankshaft main
bearing journals, this aligns the crankshaft to the
centerline of the engine and allows the crankshaft to
turn without wobbling or shaking therefore eliminat-
ing vibration. The main bearings are available in
standard and undersizes.
CRANKSHAFT
DESCRIPTION
The crankshaft is of a cast nodular steel splayed
type design, with five main bearing journals. The
crankshaft is located at the bottom of the engine
block and is held in place with five main bearing
caps. The number 3 counterweight is the location for
journal size identification (Fig. 10).
OPERATION
The crankshaft transfers force generated by com-
bustion within the cylinder bores to the flywheel or
flexplate.
DIAGNOSIS AND TESTING
ENGINE DIAGNOSISÐINTRODUCTION
Engine diagnosis is helpful in determining the
causes of malfunctions not detected and remedied by
routine maintenance.
These malfunctions may be classified as either
mechanical (e.g., a strange noise), or performance
(e.g., engine idles rough and stalls).
Refer to the Service DiagnosisÐMechanical Chart
and the Service DiagnosisÐPerformance Chart, for
possible causes and corrections of malfunctions. Refer
to FUEL SYSTEM 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:
²Cylinder Compression Pressure Test
²Cylinder Combustion Pressure Leakage Test
²Cylinder Head Gasket Failure Diagnosis
²Intake Manifold Leakage Diagnosis
²Lash Adjuster (Tappet) Noise Diagnosis
²Engine Oil Leak Inspection
Fig. 9 Main Bearing Orientation
Fig. 10 Crankshaft with Journal Size Identification
DN5.9L ENGINE 9 - 141
DESCRIPTION AND OPERATION (Continued)
Downloaded from www.Manualslib.com manuals search engine SERVICE DIAGNOSISÐGASOLINE ENGINES
PERFORMANCE DIAGNOSIS CHARTÐGASOLINE ENGINES
CONDITION POSSIBLE CAUSES CORRECTION
ENGINE WILL
NOT CRANK1. Weak or dead battery 1. Charge/Replace Battery. Refer to Group 8A,
Battery, for correct procedures. Check charging
system. Refer to Group 8C, Charging Systems, for
correct procedures.
2. Corroded or loose battery
connections2. Clean/tighten suspect battery/starter connections
3. Faulty starter or related circuit(s) 3. Check starting system. Refer to Group 8B,
Starting Systems, for correct diagnostics/procedures
4. Seized accessory drive
component4. Remove accessory drive belt and attempt to start
engine. If engine starts, repair/replace seized
component.
5. Engine internal mechanical
failure or hydro-static lock5. Refer to Group 9, Engine, for correct diagnostics/
procedures
ENGINE CRANKS
BUT WILL NOT
START1. No spark 1. Check for spark. Refer to Group 8D, Ignition
System, for correct procedures.
2. No fuel 2. Perform fuel pressure test, and if necessary,
inspect fuel injector(s) and driver circuits. Refer to
Group 14, Fuel System, for correct procedures.
3. Low or no engine compression 3. Perform cylinder compression pressure test. Refer
to Group 9, Engine, for correct procedures.
ENGINE LOSS OF
POWER1. Worn or burned distributor rotor 1. Install new distributor rotor
2. Worn distributor shaft 2. Remove and repair distributor (Refer to Group 8D,
Ignition System
3. Worn or incorrect gapped spark
plugs3. Clean plugs and set gap. (Refer to Group 8D,
Ignition System)
4. Dirt or water in fuel system 4. Clean system and replace fuel filter
5. Faulty fuel pump 5. Install new fuel pump
6. Incorrect valve timing 6. Correct valve timing
7. Blown cylinder head gasket 7. Install new cylinder head gasket
8. Low compression 8. Test cylinder compression
9. Burned, warped, or pitted valves 9. Install/Reface valves as necessary
10. Plugged or restricted exhaust
system10. Install new parts as necessary
11. Faulty ignition cables 11. Replace any cracked or shorted cables
12. Faulty ignition coil 12. Test and replace, as necessary (Refer to Group
8D, Ignition System)
ENGINE STALLS
OR ROUGH IDLE1. Carbon build-up on throttle plate 1. Remove throttle body and de-carbon. (Refer to
Group 14 for correct procedures)
2. Engine idle speed too low 2. Check Idle Air Control circuit. (Refer to Group 14,
Fuel System)
9 - 142 5.9L ENGINEDN
DIAGNOSIS AND TESTING (Continued)
Downloaded from www.Manualslib.com manuals search engine CONDITION POSSIBLE CAUSES CORRECTION
3. Worn or incorrectly gapped spark
plugs3. Replace or clean and re-gap spark plugs (Refer to
group 8D, Ignition System)
4. Worn or burned distributor rotor 4. Install new distributor rotor
5. Spark plug cables defective or
crossed5. Check for correct firing order or replace spark plug
cables. (Refer to Group 8D, Ignition System for
correct procedures.)
6. Faulty coil 6. Test and replace, if necessary (Refer to group 8D,
Ignition System)
7. Intake manifold vacuum leak 7. Inspect intake manifold gasket and vacuum hoses.
Replace if necessary
8. EGR valve leaking or stuck open 8. Test and replace, if necessary (Refer to group 25,
Emission Control Systems)
ENGINE MISSES
ON
ACCELERATION1. Worn or incorrectly gapped spark
plugs1. Replace spark plugs or clean and set gap. (Refer
to group 8D, Ignition System)
2. Spark plug cables defective or
crossed2. Replace or rewire secondary ignition cables. Refer
to Group 8D, Ignition System
3. Dirt in fuel system 3. Clean fuel system
4. Burned, warped or pitted valves 4. Install new valves
5. Faulty coil 5. Test and replace as necessary (refer to group 8D,
Ignition System)
MECHANICAL DIAGNOSIS CHARTÐGASOLINE ENGINES
CONDITION POSSIBLE CAUSES CORRECTION
NOISY VALVES/
LIFTERS1. High or low oil level
in crankcase1. Check for correct oil level. Adjust oil level by draining or adding
as needed
2. Thin or diluted oil 2. Change oil (Refer to Engine Oil Service in this group)
3. Low oil pressure 3. Check engine oil level. If ok, Perform oil pressure test. Refer to
this group for engine oil pressure test/specifications
4. Dirt in tappets/lash
adjusters4. Clean/replace hydraulic tappets/lash adjusters
5. Bent push rod(s) 5. Install new push rods
6. Worn rocker arms 6. Inspect oil supply to rocker arms and replace worn arms as
needed
7. Worn tappets/lash
adjusters7. Install new hydraulic tappets/lash adjusters
8. Worn valve guides 8. Inspect all valve guides and replace as necessary
9. Excessive runout of
valve seats or valve
faces9. Grind valves and seats
DN5.9L ENGINE 9 - 143
DIAGNOSIS AND TESTING (Continued)
Downloaded from www.Manualslib.com manuals search engine CONDITION POSSIBLE CAUSES CORRECTION
CONNECTING
ROD NOISE1. Insufficient oil supply 1. Check engine oil level. (Refer to group 0, Lubrication and
Maintenance)
2. Low oil pressure 2. Check engine oil level. If ok, Perform oil pressure test. Refer to
this group for engine oil pressure test/specifications
3. Thin or diluted oil 3. Change oil to correct viscosity. Refer to this group for correct
procedure/engine oil specifications
4. Excessive connecting
rod bearing clearanceMeasure bearings for correct clearance with plasti-gage. Repair
as necessary
5. Connecting rod
journal out of round5. Replace crankshaft or grind journals
6. Misaligned
connecting rods6. Replace bent connecting rods
MAIN BEARING
NOISE1. Insufficient oil supply 1. Check engine oil level. (Refer to group 0, Lubrication and
Maintenance)
2. Low oil pressure 2. Check engine oil level. If ok, Perform oil pressure test. Refer to
this group for engine oil pressure test/specifications
3. Thin or diluted oil 3. Change oil to correct viscosity. Refer to this group for correct
procedure/engine oil specifications
4. Excessive main
bearing clearance4. Measure bearings for correct clearance. Repair as necessary
5. Excessive end play 5. Check crankshaft thrust bearing for excessive wear on flanges
6. Crankshaft main
journal out of round or
worn6. Grind journals or replace crankshaft
7. Loose flywheel or
torque converter7. Inspect crankshaft, flexplate/flywheel and bolts for damage.
Tighten to correct torque
LOW OIL
PRESSURE1. Low oil level 1. Check oil level and fill if necessary
2. Faulty oil pressure
sending unit2. Install new sending unit
3. Clogged oil filter 3. Install new oil filter
4. Worn oil pump 4. Replace worn gears or oil pump assy
5. Thin or diluted oil 5. Change oil to correct viscosity. Refer to this group for correct
procedure/engine oil specifications
6. Excessive bearing
clearance6. Measure bearings for correct clearance
7. Oil pump relief valve
stuck7. Remove valve to inspect, clean and reinstall
8. Oil pump suction
tube loose, broken, bent
or clogged8. Inspect suction tube and clean or replace if necessary
9. Oil pump cover
warped or cracked9. Install new oil pump
9 - 144 5.9L ENGINEDN
DIAGNOSIS AND TESTING (Continued)