Ensurethebatteryiscompletelychargedandtheenginestartermotorisingood 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 - ELECTRICAL/IGNITION CONTROL/AUTO SHUTDOWNRELAY-
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 cylinders.
7. (Refer to 9 - ENGINE - SPECIFICATIONS) for the correct engine compression pressures.
DIAGNOSIS AND TESTING - CYLINDERCOMBUSTION PRESSURE LEAKAGE
The combustion pressure leakage test provides an accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
Exhaust and intake valve leaks (improper seating).
Leaks between adjacent cylinders or into water jacket.
Any causes for combustion/compression pressure loss.
1. Check the coolant level and fill as required. DO NOT install the radiatorcap.
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 manufacturer’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) recommended.
7. Perform the test procedures on each cylinder according to the tester manufacturer’s instructions. Set piston of
cylinder to be tested at TDC compression,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 pressure, a minimum of 414 kPa (60 psi) should be maintained 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
TAILPIPEExhaust 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
CONDITION POSSIBLE CAUSE CORRECTION
MORE THAN 25% LEAKAGE AND
AIR ESCAPES THROUGH OIL
FILLER CAP OPENING ONLYStuckorbrokenpistonrings;
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
DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - INTRODUCTION
Engine diagnosis is helpful in determining the causes of malfunctions notdetected and remedied by routine main-
tenance.
These malfunctions may be classified as either performance (e.g., engineidles rough and stalls) or mechanical
(e.g., a strange noise).
(Refer to 9 - ENGINE - DIAGNOSIS AND TESTING) - PERFORMANCE and (Refer to 9 - ENGINE - DIAGNOSIS
AND TESTING)—MECHANICAL 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 - DIAGNO-
SIS AND TESTING) for the fuel system diagnosis.
Additional tests and diagnostic procedures may be necessary for specificengine malfunctions that can not be iso-
lated with the Service Diagnosis charts. Information concerning additional tests and diagnosis is provided within the
following diagnosis:
Cylinder Compression Pressure Test (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
Cylinder Combustion Pressure LeakageTest (Refer to 9 - ENGINE - DIAGNOSISAND TESTING).
Engine Cylinder Head Gasket Failure Diagnosis (Refer to 9 - ENGINE/CYLINDER HEAD - DIAGNOSIS AND
TESTING).
Intake Manifold Leakage Diagnosis (Refer to 9 - ENGINE/MANIFOLDS/INTAKEMANIFOLD - DIAGNOSIS
AND TESTING).
STANDARD PROCEDURE
STANDARD PROCEDURE - REPAIR DAMAGED OR WORN THREADS
CAUTION: Be sure that the tapped holes maintain the original center line.
Damaged or worn threads can be repaired. Essentially, this repair consistsof:
Drilling out worn or damaged threads.
Tapping the hole with a special Heli-Coil Tap, or equivalent.
Installing an insert into the tapped hole to bring the hole back to its original thread size.
STANDARD PROCEDURE - FORM-IN-PLACE GASKETS AND SEALERS
There are numerous places where form-in-place gaskets are used on the engine. Care must be taken when apply-
ing form-in-place gaskets to assure obtaining the desired results.Do not use form-in-place gasket material
unless specified.Bead size, continuity, and location are of great importance. Too thin a bead can result in leakage
while too much can result in spill-overwhich can break off and obstruct fluid feed lines. A continuous bead of the
proper width is essential to obtain a leak-free gasket.
There are numerous types of form-in-place gasket materials that are used in the engine area. Mopar
Engine RTV
GEN II, Mopar
ATF-RTV, and MoparGasket Maker gasket materials, each have different properties and can not
be used in place of the other.
MOPAR
ENGINE RTV GEN II
Mopar
Engine RTV GEN II is used to seal components exposed to engine oil. This material is a specially designed
black silicone rubber RTV that retains adhesion and sealing properties when exposed to engine oil. Moisture in the
air causes the material to cure. This material is available in three ounce tubes and has a shelf life of one year. After
one year this material will not properly cure. Always inspect the package for the expiration date before use.
MOPAR
AT F R T V
Mopar
ATF RTV is a specifically designed black silicone rubber RTV that retains adhesion and sealing properties
to seal components exposed to automatic transmission fluid, engine coolants, and moisture. This material is avail-
able in three ounce tubes and has a shelf life of one year. After one year thismaterial will not properly cure. Always
inspect the package for the expiration date before use.
MOPAR
GASKET MAKER
Mopar
Gasket Maker is an anaerobic type gasket material. The material cures in the absence of air when
squeezed between two metallic surfaces. It will not cure if left in the uncovered tube. The anaerobic material is for
use between two machined surfaces. Do not use on flexible metal flanges.
MOPAR
GASKET SEALANT
Mopar
Gasket Sealant is a slow drying, permanently soft sealer. This material isrecommended for sealing
threaded fittings and gaskets against leakage of oil and coolant. Can be used on threaded and machined parts
under all temperatures. This material is used on engines with multi-layersteel (MLS) cylinder head gaskets. This
material also will prevent corrosion. Mopar
Gasket Sealant is available in a 13 oz. aerosol can or 4oz./16 oz. can
w/applicator.
FORM-IN-PLACE GASKET AND SEALER APPLICATION
Assembling parts using a form-in-place gasket requires care but it’s easier than using precut gaskets.
Mopar
Gasket Maker material should be applied sparingly 1 mm (0.040 in.) diameter or less of sealant to one
gasket surface. Be certain the material surrounds each mounting hole. Excess material can easily be wiped off.
Components should be torqued in place within 15 minutes. The use of a locating dowel is recommended during
assembly to prevent smearing material off the location.
Mopar
Engine RTV GEN II or ATF RTV gasket material should be applied in a continuous bead approximately 3
mm (0.120 in.) in diameter. All mounting holes must be circled. For corner sealing, a 3.17 or 6.35 mm (1/8 or 1/4 in.)
drop is placed in the center of the gasket contact area. Uncured sealant maybe removed with a shop towel. Com-
ponents should be torqued in place while the sealant is still wet to the touch (within 10 minutes). The usage of a
locating dowel is recommended during assembly to prevent smearing material off the location.
Mopar
Gasket Sealant in an aerosol can should be applied using a thin, even coat sprayed completely over both
surfaces to be joined, and both sides of a gasket. Then proceed with assembly. Material in a can w/applicator can
be brushed on evenly over the sealing surfaces. Material in an aerosol can shouldbeusedonengineswithmulti-
layer steel gaskets.
REMOVAL
NOTE:Thisprocedureappliestoboththe4X2and4X4vehicles,stepsthatapply to the 4X4 vehicle only,
are identified.
1. Release fuel rail pressure (Refer to 14 - FUEL SYSTEM/FUEL DELIVERY - STANDARD PROCEDURE) then
disconnect the fuel supply quick connect fitting at the fuel rail (Refer to14 - FUEL SYSTEM/FUEL DELIVERY/
QUICK CONNECT FITTING - STANDARD PROCEDURE).
2. Disconnect the battery negative and positive cables.
3. Raise vehicle on hoist.
4. Remove exhaust crossover pipe from exhaust manifolds.
5.4X4 vehiclesDisconnect axle vent tube from left side engine mount.
6. Remove the through bolt retaining nut and bolt from both the left and right side engine mounts.
7.4X4 vehiclesRemove locknut from left and right side engine mount brackets.
8. Disconnect two ground straps from the lower left hand side and one groundstrap from the lower right hand side
of the engine.
30. Disconnect engine harness at the following points
:
Intake air temperature (IAT) sensor (4)
Fuel Injectors
Throttle Position (TPS) Switch (2)
Idle Air Control (IAC) Motor (3)
Engine Oil Pressure Switch
Engine Coolant Temperature (ECT) Sensor
Manifold absolute pressure (MAP) Sensor
Camshaft Position (CMP) Sensor
Coil Over Plugs
31. Disconnect the vacuum lines at the throttle body
and intake manifold.
32. Remove power steering pump and position out of
the way.
33. Install Special Tools 8400 Lifting Studs, into the
cylinder heads.
34. Install Engine Lifting Fixture Special Tool 8347 (3)
following these steps.
Holding the lifting fixture at a slight angle, slide
the large bore in the front plate over the hex por-
tion of the lifting stud.
Position the two remaining fixture arms onto the
two Special Tools 8400 Lifting Studs, in the cyl-
inder heads.
Pull foward and upward on the lifting fixture so
that the lifting stud rest in the slotted area below
the large bore.
Secure the lifting fixture to the three studs using
three 7/16 – 14 N/C locknuts.
Make sure the lifting loop in the lifting fixture is in
the last hole (closest to the throttle body) to min-
imize the angle of engine during removal.
6. Position generator wiring behind the oil dipstick
tube, then install the oil dipstick tube upper mount-
ing bolt.
7. Connect both left (2) and right (3) side body ground
straps.
8. Install power steering pump.
9. Connect fuel supply line quick connect fitting (Refer
to 14 - FUEL SYSTEM/FUEL DELIVERY/QUICK
CONNECT FITTING - STANDARD PROCEDURE).
10. Connect the vacuum lines at the throttle body and
intake manifold.
11. Connect engine harness at the following points :
Intake Air Temperature (IAT) Sensor (4)
Idle Air Control (IAC) Motor (3)
Fuel Injectors
Throttle Position (TPS) Switch (2)
Engine Oil Pressure Switch
Engine Coolant Temperature (ECT) Sensor
Manifold Absolute Pressure (MAP) Sensor
Camshaft Position (CMP) Sensor
Coil Over Plugs
OIL PRESSURE
SPECIFICATION SPECIFICATION
At Curb Idle Speed (MIN)* 48 kPa (7 psi)
@ 3000 rpm 240 - 725 kPa (35 - 105 psi)
* CAUTION: If pressure is zero at curb idle, DO NOT run engine at 3000 rpm.
TORQUE
DESCRIPTION Nꞏm Ft. In.
Lbs. Lbs.
Camshaft
Non - Oiled Sprocket Bolt 122 90 —
Bearing Cap Bolts 11 — 100
Timing Chain Cover—Bolts 58 43 —
Connecting Rod Cap—Bolts 27 20 —
PLUS 90° TURN
Bed Plate—Bolts Refer to Procedure
Cylinder Head—Bolts Refer to Procedure
Crankshaft Damper—Bolt 175 130 —
Cylinder Head Cover—Bolts 12 — 105
Exhaust Manifold—Bolts 25 18 —
Exhaust Manifold Heat Shield—Nuts 8 — 72
Then loosen 45°
Flexplate—Bolts 60 45 —
Engine Mount Bracket to Block—Bolts 61 45 —
Rear Mount to Transmission—Bolts 46 34 —
Generator Mounting—Bolts
M10 Bolts 54 40 —
M8 Bolts 28 — 250
Intake Manifold—Bolts 12 — 105
Refer to Procedure for
Tightening Sequence
Oil Pan—Bolts 15 — 130
Oil Pan—Drain Plug 34 25 —
Oil Pump—Bolts 28 — 250
Oil Pump Cover—Bolts 12 — 105
Oil Pickup Tube—Bolt and Nut 28 — 250
Oil Dipstick Tube to Engine
Block—Bolt 15 — 130
Oil Fill Tube—Bolts 12 — 105
Timing Chain Guide—Bolts 28 — 250
Timing Chain Tensioner Arm—Pin Bolt 17 — 150
Hydraulic Tensioner—Bolts 28 — 250
Timing Chain Primary Tensioner—Bolts 28 — 250
GAUGE OIL PRESSURE - C-3292
Piston Ring Compressor C-385
Pressure Tester Kit 7700
BLOC-CHEK KIT C-3685
ENGINE SUPPORT FIXTURE 8534
ROCKER ARM - VALVE
DESCRIPTION
The rocker arms are steel stampings with an integral roller bearing. The rocker arms incorporate an 0.5 mm (0.019
inch) oil hole in the ball socket forroller and camshaft lubrication.
DIAGNOSIS AND TESTING - HYDRAULIC LASH ADJUSTER
A tappet-like noise may be produced from several items. Check the followingitems.
1. Engine oil level too high or too low. This may cause aerated oil to enter the adjusters and cause them to be
spongy.
2. Insufficient running time after rebuilding cylinder head. Low speed runningupto1hourmayberequired.
3. Turn engine off and let set for a few minutes before restarting. Repeat this several times after engine has
reached normal operating temperature.
4. Low oil pressure.
5. The oil restrictor in cylinder head gasket or the oil passage to the cylinder head is plugged with debris.
6. Airingestedintooilduetobrokenorcrackedoilpumppickup.
7. Worn valve guides.
8. Rocker arm ears contacting valve spring retainer.
9. Rocker arm loose, adjuster stuck or at maximum extension and still leaves lash in the system.
10. Oil leak or excessive cam bore wear in cylinder head.
11. Faulty lash adjuster.
a. Check lash adjusters for sponginess while installed in cylinder head and cam on camshaft at base circle.
Depress part of rocker arm over adjuster. Normal adjusters should feel very firm. Spongy adjusters can be bot-
tomed out easily.
b. Remove suspected lash adjusters, and replace.
c. Before installation, make sure adjusters are at least partially full ofoil. This can be verified by little or no
plunger travel when lash adjuster is depressed.
REMOVAL
NOTE: Disconnect the battery negative cable to
prevent accidental starter engagement.
1. Remove the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
2. For rocker arm removal on cylinders 3 and 5
Rotate the crankshaft until cylinder #1 is at TDC
exhaust stroke.
3. For rocker arm removal on cylinders 2 and 8
Rotate the crankshaft until cylinder #1 is at TDC
compression stroke.
4. For rocker arm removal on cylinders 4 and 6
Rotate the crankshaft until cylinder #3 is at TDC
compression stroke.
5. For rocker arm removal on cylinders 1 and 7
Rotate the crankshaft until cylinder #2 is at TDC
compression stroke.
6. Using special tool 8516 Rocker Arm Remover (2),
press downward on the valve spring, remove
rocker arm.