1999 DODGE DURANGO ECU

Downloaded from www.Manualslib.com manuals search engine (2) Position the cylinder head cover onto the gas-
ket. Tighten the bolts to 11 N´m (95 in. lbs.) torque.
(3) Install closed crankcase ventilation system and
evaporation control system.
(4) Install the air inlet hose.
(5) Connect the negative cable to the battery.
ROCKER ARMS AND PUSH RODS
REMOVAL
(1) Remove cylinder head cover and gasket. Refer
to Cylinder Head Cover in this section for correct
procedure.
(2) Remove the rocker arm bolts and pivots (Fig.
44). Place them on a bench in the same order as
removed.
(3) Remove the push rods and place them on a
bench in the same order as removed.
INSTALLATION
(1) Rotate the crankshaft until the ªV8º mark lines
up with the TDC mark on the timing chain case
cover. This mark is located 147É ATDC from the No.1
firing position.
(2) Install the push rods in the same order as
removed.
(3) Install rocker arm and pivot assemblies in the
same order as removed. Tighten the rocker arm bolts
to 28 N´m (21 ft. lbs.) torque.
CAUTION: DO NOT rotate or crank the engine dur-
ing or immediately after rocker arm installation.
Allow the hydraulic roller tappets adequate time to
bleed down (about 5 minutes).
(4) Install cylinder head cover.
VALVE SPRING AND STEM SEAL
REPLACEMENT-IN VEHICLE
(1) Remove the air cleaner.
(2) Remove cylinder head covers and spark plugs.(3) Remove coil wire from distributor and secure to
good ground to prevent engine from starting.
(4) Using suitable socket and flex handle at crank-
shaft retaining bolt, turn engine so the No.1 piston is
at TDC on the compression stroke.
(5) Remove rocker arms.
(6) With air hose attached to an adapter installed
in No.1 spark plug hole, apply 620-689 kPa (90-100
psi) air pressure.
(7) Using Valve Spring Compressor Tool
MD-998772A with adaptor 6716A, compress valve
spring and remove retainer valve locks and valve
spring.
(8) Install seals on the exhaust valve stem and
position down against valve guides.
(9) The intake valve stem seals should be pushed
firmly and squarely over the valve guide using the
valve stem as a guide. DO NOT force seal against top
of guide. When installing the valve retainer locks,
compress the spring only enough to install the locks.
(10) Follow the same procedure on the remaining 7
cylinders using the firing sequence 1-8-4-3-6-5-7-2.
Make sure piston in cylinder is at TDC on the valve
spring that is being removed.
(11) Remove adapter from the No.1 spark plug
hole and install spark plugs.
(12) Install rocker arms.
(13) Install covers and coil wire to distributor.
(14) Install air cleaner.
(15) Road test vehicle.
CYLINDER HEAD
REMOVAL
(1) Disconnect the battery negative cable.
(2) Drain cooling system Refer to COOLING SYS-
TEM.
(3) Remove the intake manifold-to-generator
bracket support rod. Remove the generator.
(4) Remove closed crankcase ventilation system.
(5) Disconnect the evaporation control system.
(6) Remove the air cleaner assembly and air inlet
hose.
(7) Perform fuel system pressure release proce-
dure. Refer to FUEL SYSTEM.
(8) Disconnect the fuel supply line.
(9) Disconnect accelerator linkage and if so
equipped, the speed control and transmission kick-
down cables.
(10) Remove distributor cap and wires.
(11) Disconnect the coil wires.
(12) Disconnect heat indicator sending unit wire.
(13) Disconnect heater hoses and bypass hose.
(14) Remove cylinder head covers and gaskets.
Fig. 44 Rocker Arms
1 ± ROCKER ARMS
2 ± CYLINDER HEAD
DN5.2L ENGINE 9 - 107
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine 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) Secure the throttle in the wide-open position.
(4) Disconnect the ignition coil.
(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 third
revolution. Continue the test for the remaining cylin-
ders.
Refer to Engine Specifications for the correct
engine compression pressures.
CYLINDER HEAD GASKET FAILURE DIAGNOSIS
A cylinder head gasket leak can be located between
adjacent cylinders or between a cylinder and the
adjacent water jacket.
²Possible indications of the cylinder head gasket
leaking between adjacent cylinders are:
²Loss of engine power
²Engine misfiring
²Poor fuel economy
²Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
²Engine overheating
²Loss of coolant
²Excessive steam (white smoke) emitting from
exhaust
²Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test in this
section. An engine cylinder head gasket leaking
between adjacent cylinders will result in approxi-
mately a 50±70% reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING WITH COOLANT PRES-
SURE CAP REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure
cap. Start the engine and allow it to warm up until
thermostat opens.
If a large combustion/compression pressure leak
exists, bubbles will be visible in the coolant.COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE PRESSURE BUILT UP, BY CONTINUOUS
ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to
pressure cap neck. Start the engine and observe the
tester's pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also
be checked by using Bloc-Chek Kit C-3685-A or
equivalent. Perform test following the procedures
supplied with the tool kit.
CYLINDER COMBUSTION PRESSURE LEAKAGE
TEST
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
WARNING: DO NOT REMOVE THE RADIATOR CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE.
SERIOUS BURNS FROM HOT COOLANT CAN
OCCUR.
Check the coolant level and fill as required. DO
NOT install the radiator cap.
Start and operate the engine until it attains nor-
mal operating temperature, then turn OFF the
engine.
Remove the spark plugs.
Remove the oil filler cap.
Remove the air cleaner.
Calibrate the tester according to the manufactur-
er'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.
Perform the test procedure on each cylinder accord-
ing to the tester manufacturer's instructions. While
testing, listen for pressurized air escaping through
the throttle body, tailpipe or oil filler cap opening.
Check for bubbles in the radiator coolant.
9 - 146 5.9L ENGINEDN
DIAGNOSIS AND TESTING (Continued)

Downloaded from www.Manualslib.com manuals search engine EXHAUST MANIFOLD
REMOVAL
(1) Disconnect the battery negative cable.
(2) Raise the vehicle.
(3) Remove the exhaust pipe to manifold nuts.
(4) Lower the vehicle.
(5) Remove three nuts, heat shield and washers
from the right side exhaust manifold, if necessary
(Fig. 45).
(6) Remove two nuts, heat shield and washers
from the left side exhaust manifold, if necessary (Fig.
46).
(7) Remove bolts, nuts and washers attaching
manifold to cylinder head.
(8) Remove manifold from the cylinder head.
INSTALLATION
CAUTION: If the studs came out with the nuts when
removing the exhaust manifold, install new studs.
(1) Position the exhaust manifolds on the two
studs located on the cylinder head. Install conical
washers and nuts on these studs (Fig. 47).
(2) Install new bolt and washer assemblies in the
remaining holes (Fig. 47). Start at the center arm
and work outward. Tighten the bolts and nuts to 24
N´m (18 ft. lbs.) torque.
(3) Position three washers, heat shield and nuts on
the right side exhaust manifold. Tighten nuts to 24
N´m (18 ft. lbs.).
(4) Position two washers, heat shield and nuts on
the left side exhaust manifold. Tighten nuts to 24
N´m (18 ft. lbs.).
(5) Raise the vehicle.(6) Assemble the exhaust pipe to the exhaust man-
ifold and secure with bolts, nuts and washers.
Tighten these nuts to 27 N´m (20 ft. lbs.) torque.
(7) Lower the vehicle.
(8) Connect the battery negative cable.
CYLINDER HEAD COVER
A steel backed silicon gasket is used with the cyl-
inder head cover (Fig. 48). This gasket can be used
again.
REMOVAL
(1) Disconnect the negative cable from the battery.
Fig. 45 Exhaust Manifold Heat ShieldÐRight Side
1 ± WASHER
2 ± NUT AND WASHER
3 ± EXHAUST MANIFOLD HEAT SHIELD
Fig. 46 Exhaust Manifold Heat ShieldÐLeft Side
1 ± WASHER
2 ± NUT AND WASHER
3 ± EXHAUST MANIFOLD HEAT SHIELD
Fig. 47 Exhaust Manifold InstallationÐ5.9L Engine
1 ± EXHAUST MANIFOLD (LEFT)
2 ± BOLTS & WASHERS
3 ± NUTS & WASHERS
4 ± EXHAUST MANIFOLD (RIGHT)
5 ± BOLTS & WASHERS
DN5.9L ENGINE 9 - 165
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine (2) Disconnect closed ventilation system and evap-
oration control system from cylinder head cover.
(3) Remove the air inlet hose.
(4) Remove cylinder head cover and gasket. The
gasket may be used again.
INSTALLATION
(1) The cylinder head cover gasket can be used
again. Install the gasket onto the head rail.
(2) Position the cylinder head cover onto the gas-
ket. Tighten the bolts to 11 N´m (95 in. lbs.) torque.
(3) Install closed crankcase ventilation system and
evaporation control system.
(4) Install the air inlet hose.
(5) Connect the negative cable to the battery.
ROCKER ARMS AND PUSH RODS
REMOVAL
(1) Remove cylinder head cover and gasket. Refer
to Cylinder Head Cover in this section for correct
procedure.
(2) Remove the rocker arm bolts and pivots (Fig.
49). Place them on a bench in the same order as
removed.
(3) Remove the push rods and place them on a
bench in the same order as removed.
INSTALLATION
(1) Rotate the crankshaft until the ªV8º mark lines
up with the TDC mark on the timing chain case
cover. This mark is located 147É ATDC from the No.1
firing position.
(2) Install the push rods in the same order as
removed.
(3) Install rocker arm and pivot assemblies in the
same order as removed. Tighten the rocker arm bolts
to 28 N´m (21 ft. lbs.) torque.
CAUTION: DO NOT rotate or crank the engine dur-
ing or immediately after rocker arm installation.
Allow the hydraulic roller tappets adequate time to
bleed down (about 5 minutes).
(4) Install cylinder head cover.
VALVE SPRING AND STEM SEAL
REPLACEMENT-IN VEHICLE
(1) Remove the air cleaner.
(2) Remove cylinder head covers and spark plugs.
(3) Remove coil wire from distributor and secure to
good ground to prevent engine from starting.
(4) Using suitable socket and flex handle at crank-
shaft retaining bolt, turn engine so the No.1 piston is
at TDC on the compression stroke.
(5) Remove rocker arms.
(6) With air hose attached to an adapter installed
in No.1 spark plug hole, apply 620-689 kPa (90-100
psi) air pressure.
(7) Using Valve Spring Compressor Tool
MD-998772A with adaptor 6716A, compress valve
spring and remove retainer valve locks and valve
spring.
(8) Install seals on the exhaust valve stem and
position down against valve guides.
(9) The intake valve stem seals should be pushed
firmly and squarely over the valve guide using the
valve stem as a guide. DO NOT force seal against top
of guide. When installing the valve retainer locks,
compress the spring only enough to install the locks.
(10) Follow the same procedure on the remaining 7
cylinders using the firing sequence 1-8-4-3-6-5-7-2.
Make sure piston in cylinder is at TDC on the valve
spring that is being removed.
(11) Remove adapter from the No.1 spark plug
hole and install spark plugs.
(12) Install rocker arms.
(13) Install covers and coil wire to distributor.
(14) Install air cleaner.
(15) Road test vehicle.
Fig. 48 Cylinder Head Cover Gasket
1 ± CYLINDER HEAD COVER GASKET
Fig. 49 Rocker Arms
1 ± ROCKER ARMS
2 ± CYLINDER HEAD
9 - 166 5.9L ENGINEDN
REMOVAL AND INSTALLATION (Continued)