Dodge Durango (HB). Manual — part 1063
VALVES & SEATS - INTAKE/EXHAUST
DESCRIPTION
The valves are made of heat resistant steel and have chrome plated stems to prevent scuffing. Each valve is actu-
ated by a roller rocker arm which pivots on a stationary lash adjuster. All valves use three bead lock keepers to
retain the springs and promote valve rotation.
STANDARD PROCEDURE - REFACING
NOTE: Valve seats that are worn or burned can be
reworked, provided that correct angle and seat
width are maintained. Otherwise the cylinder head
must be replaced.
NOTE: When refacing valves (4) and valve seats, it
is important that the correct size valve guide pilot
be used for reseating stones. A true and complete
surface must be obtained.
1. Using a suitable dial indicator measure the center
of the valve seat Total run out must not exceed
0.051 mm (0.002 in).
2. Apply a small amount of Prussian blue to the valve
seat, insert the valve into the cylinder head, while
applying light pressure on the valve rotate the
valve. Remove the valve and examine the valve
face. If the blue is transferred below the top edge
of the valve face, lower the valve seat using a 15
degree stone. If the blue is transferred to the bot-
tom edge of the valve face, raise the valve seat
using a 65 degree stone.
3. When the seat is properly positioned the width of the intake seat must be 1.75 - 2.36 mm (0.0689 - 0.0928 in.)
and the exhaust seat must be 1.71 - 2.32 mm (0.0673 - 0.0911 in.).
4. Check the valve spring (6) installed height after refacing the valve and seat. The installed height for both intake
and exhaust valve springs must not exceed 40.74 mm (1.6039 in.).
5. The valve seat and valve face must maintain a face angle of 44.5 - 45 ° angle .
ROCKER ARM-VALVE
DESCRIPTION
The rocker arms are steel stampings with an integral roller bearing. The rocker arms incorporate a 2.8 mm (0.11
inch) oil hole in the lash adjuster socket for roller and camshaft lubrication.
DIAGNOSIS AND TESTING - HYDRAULIC LASH ADJUSTER
A tappet-like noise may be produced from several items. Check the following items.
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 running up to 1 hour may be required.
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.
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ENGINE - 4.7L SERVICE INFORMATION
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6. Air ingested into oil due to broken or cracked oil pump pick up.
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 of oil. 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.
INSTALLATION
CAUTION: Make sure the rocker arms are installed with the concave pocket over the lash adjusters. Failure
to do so may cause severe damage to the rocker arms and/or lash adjusters.
NOTE: Coat the rocker arms with clean engine oil prior to installation.
1. For rocker arm installation on cylinders 3 and 5 Rotate the crankshaft until cylinder #1 is at TDC exhaust stroke.
2. For rocker arm installation on cylinders 2 and 8 Rotate the crankshaft until cylinder #1 is at TDC compression
stroke.
3. For rocker arm installation on cylinders 4 and 6 Rotate the crankshaft until cylinder #3 is at TDC compression
stroke.
4. For rocker arm installation on cylinders 1 and 7 Rotate the crankshaft until cylinder #2 is at TDC compression
stroke.
5. Using special tool 8516 press downward on the valve spring, install rocker arm.
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ENGINE - 4.7L SERVICE INFORMATION
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6. Install the cylinder head cover (Refer to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) -
INSTALLATION).
SPRINGS-VALVE
DESCRIPTION
The valve springs are made from high strength chrome silicon steel. The springs are common for intake and
exhaust applications. The valve spring seat is integral with the valve stem seal, which is a positive type seal to
control lubrication.
REMOVAL
1. Remove the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER
HEAD/CYLINDER
HEAD
COVER(S) - REMOVAL).
2. Using Special Tool 8516 Rocker Arm Remover (2),
remove the rocker arms and the hydraulic lash
adjusters.
3. Remove the spark plug for the cylinder the valve
spring and seal are to be removed from.
4. Apply shop air to the cylinder to hold the valves in
place when the spring is removed
NOTE: All eight valve springs and seals are
removed in the same manner; this procedure only
covers one valve seal and valve spring.
5. Using Special Tool 8387 Valve Spring Compressor,
compress the valve spring.
NOTE: It may be necessary to tap the top of the
valve spring to loosen the spring retainers locks
enough to be removed.
6. Remove the two spring retainer lock halves.
NOTE: the valve spring is under tension use care when releasing the valve spring compressor.
7. Remove the valve spring compressor.
8. Remove the spring retainer, and the spring.
9. Remove the valve stem seal.
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ENGINE - 4.7L SERVICE INFORMATION
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NOTE: The valve stem seals are common between intake and exhaust.
INSTALLATION
1. Coat the valve stem with clean engine oil and
install the valve stem seal. Make sure the seal is
fully seated and that the garter spring at the top of
the seal is intact.
2. Install the spring (6) and the spring retainer (2).
3. Using Special Tool 8387 Valve Spring Compressor,
compress the spring and install the two valve
spring retainer halves.
4. Release the valve spring compressor and make
sure the two spring retainer halves and the spring
retainer are fully seated.
5. Position the hydraulic lash adjusters and rocker
arms.
6. Install the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER
HEAD/CYLINDER
HEAD
COVER(S) - INSTALLATION).
SEALS-VALVE GUIDE
DESCRIPTION
The valve stem seals are made of rubber and incorporate an integral steel valve spring seat. The integral garter
spring maintains consistent lubrication control to the valve stems.
ENGINE BLOCK
DESCRIPTION
The cylinder block is made of cast iron. The block is a closed deck design with the left bank forward. To provide
high rigidity and improved NVH an enhanced compacted graphite bedplate is bolted to the block. The block design
allows coolant flow between the cylinders bores, and an internal coolant bypass to a single poppet inlet thermostat
is included in the cast aluminum front cover.
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ENGINE - 4.7L SERVICE INFORMATION
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