1999 DODGE DURANGO ESP

Downloaded from www.Manualslib.com manuals search engine The hydraulic valve tappets receive oil directly
from the main oil gallery. The camshaft bearings
receive oil from the main bearing galleries. The front
camshaft bearing journal passes oil through the cam-
shaft sprocket to the timing chain. Oil drains back to
the oil pan under the No. 1 main bearing cap.
The oil supply for the rocker arms and bridged
pivot assemblies is provided by the hydraulic valvetappets, which pass oil through hollow push rods to a
hole in the corresponding rocker arm. Oil from the
rocker arm lubricates the valve train components.
The oil then passes down through the push rod guide
holes and the oil drain-back passages in the cylinder
head, past the valve tappet area, and then returns to
the oil pan.
DN5.9L ENGINE 9 - 137
DESCRIPTION AND OPERATION (Continued)

Downloaded from www.Manualslib.com manuals search engine HYDRAULIC TAPPETS
Before disassembling any part of the engine to cor-
rect tappet noise, check the oil pressure. If vehicle
has no oil pressure gauge, install a reliable gauge at
the pressure sending-unit. The pressure should be
between 207-552 kPa (30-80 psi) at 3,000 RPM.
Check the oil level after the engine reaches normal
operating temperature. Allow 5 minutes to stabilize
oil level, check dipstick. The oil level in the pan
should never be above the FULL mark or below the
ADD OIL mark on dipstick. Either of these two con-
ditions could be responsible for noisy tappets.
OIL LEVEL
HIGH
If oil level is above the FULL mark, it is possible
for the connecting rods to dip into the oil. With the
engine running, this condition could create foam in
the oil pan. Foam in oil pan would be fed to the
hydraulic tappets by the oil pump causing them to
lose length and allow valves to seat noisily.
LOW
Low oil level may allow oil pump to take in air.
When air is fed to the tappets, they lose length,
which allows valves to seat noisily. Any leaks on
intake side of oil pump through which air can be
drawn will create the same tappet action. Check the
lubrication system from the intake strainer to the
pump cover, including the relief valve retainer cap.
When tappet noise is due to aeration, it may be
intermittent or constant, and usually more than one
tappet will be noisy. When oil level and leaks have
been corrected, operate the engine at fast idle. Run
engine for a sufficient time to allow all of the air
inside the tappets to be bled out.
TAPPET NOISE DIAGNOSIS
(1) To determine source of tappet noise, operate
engine at idle with cylinder head covers removed.
(2) Feel each valve spring or rocker arm to detect
noisy tappet. The noisy tappet will cause the affected
spring and/or rocker arm to vibrate or feel rough in
operation.
NOTE: Worn valve guides or cocked springs are
sometimes mistaken for noisy tappets. If such is
the case, noise may be dampened by applying side
thrust on the valve spring. If noise is not apprecia-
bly reduced, it can be assumed the noise is in the
tappet. Inspect the rocker arm push rod sockets
and push rod ends for wear.
(3) Valve tappet noise ranges from light noise to a
heavy click. A light noise is usually caused by exces-
sive leak-down around the unit plunger, or by theplunger partially sticking in the tappet body cylinder.
The tappet should be replaced. A heavy click is
caused by a tappet check valve not seating, or by for-
eign particles wedged between the plunger and the
tappet body. This will cause the plunger to stick in
the down position. This heavy click will be accompa-
nied by excessive clearance between the valve stem
and rocker arm as valve closes. In either case, tappet
assembly should be removed for inspection and clean-
ing.
(4) The valve train generates a noise very much
like a light tappet noise during normal operation.
Care must be taken to ensure that tappets are mak-
ing the noise. If more than one tappet seems to be
noisy, it's probably not the tappets.
LEAK-DOWN TEST
After cleaning and inspection, test each tappet for
specified leak-down rate tolerance to ensure zero-lash
operation (Fig. 11).
Swing the weighted arm of the hydraulic valve tap-
pet tester away from the ram of the Universal Leak-
Down Tester.
(1) Place a 7.925-7.950 mm (0.312-0.313 inch)
diameter ball bearing on the plunger cap of the tap-
pet.
(2) Lift the ram and position the tappet (with the
ball bearing) inside the tester cup.
(3) Lower the ram, then adjust the nose of the ram
until it contacts the ball bearing. DO NOT tighten
the hex nut on the ram.
(4) Fill the tester cup with hydraulic valve tappet
test oil until the tappet is completely submerged.
(5) Swing the weighted arm onto the push rod and
pump the tappet plunger up and down to remove air.
When the air bubbles cease, swing the weighted arm
away and allow the plunger to rise to the normal
position.
(6) Adjust the nose of the ram to align the pointer
with the SET mark on the scale of the tester and
tighten the hex nut.
(7) Slowly swing the weighted arm onto the push
rod.
(8) Rotate the cup by turning the handle at the
base of the tester clockwise one revolution every 2
seconds.
(9) Observe the leak-down time interval from the
instant the pointer aligns with the START mark on
the scale until the pointer aligns with the 0.125
mark. A normally functioning tappet will require
20-110 seconds to leak-down. Discard tappets with
leak-down time interval not within this specification.
ENGINE OIL PRESSURE
(1) Remove oil pressure sending unit.
9 - 148 5.9L ENGINEDN
DIAGNOSIS AND TESTING (Continued)

Downloaded from www.Manualslib.com manuals search engine (7) Place timing chain around both sprockets.
(8) Turn crankshaft and camshaft to line up with
keyway location in crankshaft sprocket and in cam-
shaft sprocket.
(9) Lift sprockets and chain (keep sprockets tight
against the chain in position as described).
(10) Slide both sprockets evenly over their respec-
tive shafts and use a straightedge to check alignment
of timing marks (Fig. 25).
(11) Install the camshaft bolt. Tighten the bolt to
47 N´m (35 ft. lbs.) torque.
(12) Check camshaft end play. The end play should
be 0.051-0.152 mm (0.002-0.006 inch) with a new
thrust plate and up to 0.254 mm (0.010 inch) with a
used thrust plate. If not within these limits install a
new thrust plate.
PISTONSÐFITTING
Piston and cylinder wall must be clean and dry.
Specified clearance between the piston and the cylin-
der wall is 0.013-0.038 mm (0.0005-0.0015 inch) at
21ÉC (70ÉF).
Piston diameter should be measured at the top of
skirt, 90É to piston pin axis. Cylinder bores should be
measured halfway down the cylinder bore and trans-
verse to the engine crankshaft center line.
Pistons and cylinder bores should be measured at
normal room temperature, 21ÉC (70ÉF).
Check the pistons for taper and elliptical shape
before they are fitted into the cylinder bore (Fig. 26).
PISTON RINGSÐFITTING
(1) Measurement of end gaps:
(a) Measure piston ring gap 2 inches from bot-
tom of cylinder bore. An inverted piston can be
used to push the rings down to ensure positioning
rings squarely in the cylinder bore before measur-
ing.
(b) Insert feeler gauge in the gap. The top com-
pression ring gap should be between 0.254-0.508
mm (0.010-0.020 inch). The second compressionring gap should be between 0.508-0.762 mm (0.020-
0.030 inch). The oil ring gap should be 0.254-1.270
mm (0.010-0.050 inch).
(c) Rings with insufficient end gap may be prop-
erly filed to the correct dimension. Rings with
excess gaps should not be used.
(2) Install rings and confirm ring side clearance:
(a) Install oil rings being careful not to nick or
scratch the piston. Install the oil control rings
according to instructions in the package. It is not
necessary to use a tool to install the upper and
lower rails. Insert oil rail spacer first, then side
rails.
(b) Install the second compression rings using
Installation Tool C-4184. The compression rings
must be installed with the identification mark face
up (toward top of piston) and chamfer facing down.
An identification mark on the ring is a drill point,
a stamped letter ªOº, an oval depression or the
word TOP (Fig. 27) (Fig. 29).
(c) Using a ring installer, install the top com-
pression ring with the chamfer facing up (Fig. 28)
(Fig. 29). An identification mark on the ring is a
drill point, a stamped letter ªOº, an oval depression
or the word TOP facing up.
(d) Measure side clearance between piston ring
and ring land. Clearance should be 0.074-0.097 mm
(0.0029-0.0038 inch) for the compression rings. The
steel rail oil ring should be free in groove, but
should not exceed 0.246 mm (0.0097 inch) side
clearance.
(e) Pistons with insufficient or excessive side
clearance should be replaced.
Fig. 25 Alignment of Timing Marks
1 ± TIMING MARKS
Fig. 26 Piston Measurements
1 ± 49.53 mm
(1.95 IN.)
9 - 156 5.9L ENGINEDN
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine (10) Remove the vibration damper bolt and seal
installation tool.
(11) Install vibration damper.(12) Install water pump and housing assembly
using new gaskets (refer to Group 7, Cooling Sys-
tem). Tighten bolts to 41 N´m (30 ft. lbs.) torque.
(13) Install power steering pump (refer to Group
19, Steering).
(14) Install the serpentine belt (refer to Group 7,
Cooling System).
(15) Install the cooling system fan. Tighten the
bolts to 23 N´m (17 ft. lbs.) torque.
(16) Position the fan shroud and install the bolts.
Tighten the bolts to 11 N´m (95 in. lbs.) torque.
(17) Fill cooling system (refer to Group 7, Cooling
System for the proper procedure).
(18) Connect the negative cable to the battery.
TIMING CHAIN
REMOVAL
(1) Disconnect battery negative cable.
(2) Remove Timing Chain Cover. Refer to Timing
Chain Cover in this section for correct procedure.
(3) Re-install the vibration damper bolt finger
tight. Using a suitable socket and breaker bar, rotate
the crankshaft to align timing marks as shown in
(Fig. 57).
(4) Remove camshaft sprocket attaching bolt and
remove timing chain with crankshaft and camshaft
sprockets.
INSTALLATION
(1) Place both camshaft sprocket and crankshaft
sprocket on the bench with timing marks on exact
imaginary center line through both camshaft and
crankshaft bores.
(2) Place timing chain around both sprockets.
(3) Turn crankshaft and camshaft to line up with
keyway location in crankshaft sprocket and in cam-
shaft sprocket.
(4) Lift sprockets and chain (keep sprockets tight
against the chain in position as described).
(5) Slide both sprockets evenly over their respec-
tive shafts and use a straightedge to check alignment
of timing marks (Fig. 57).
(6) Install the camshaft bolt. Tighten the bolt to 68
N´m (50 ft. lbs.) torque.
(7) Check camshaft end play. The end play should
be 0.051-0.152 mm (0.002-0.006 inch) with a new
thrust plate and up to 0.254 mm (0.010 inch) with a
used thrust plate. If not within these limits install a
new thrust plate.
(8) Install the timing chain cover.
CAMSHAFT
NOTE: The camshaft has an integral oil pump and
distributor drive gear (Fig. 58).
Fig. 55 Position Tool and Seal onto Crankshaft
1 ± SPECIAL TOOL 6635
2 ± OIL SEAL
3 ± TIMING CHAIN COVER
Fig. 56 Installing Oil Seal
1 ± SPECIAL TOOL 6635
2 ± TIMING CHAIN COVER
9 - 170 5.9L ENGINEDN
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine torque. Top edge of tab should be flat against thrust
plate in order to catch oil for chain lubrication.
(5) Place both camshaft sprocket and crankshaft
sprocket on the bench with timing marks on exact
imaginary center line through both camshaft and
crankshaft bores.
(6) Place timing chain around both sprockets.
(7) Turn crankshaft and camshaft to line up with
keyway location in crankshaft sprocket and in cam-
shaft sprocket.
(8) Lift sprockets and chain (keep sprockets tight
against the chain in position as described).
(9) Slide both sprockets evenly over their respec-
tive shafts and use a straightedge to check alignment
of timing marks (Fig. 61).
(10) Install the camshaft bolt/cup washer. Tighten
bolt to 68 N´m (50 ft. lbs.) torque.
(11) Measure camshaft end play. Refer to Specifica-
tions for proper clearance. If not within limits install
a new thrust plate.
(12) Each tappet reused must be installed in the
same position from which it was removed.When
camshaft is replaced, all of the tappets must be
replaced.
(13) Install distributor and distributor drive shaft.
(14) Install push rods and tappets.
(15) Install rocker arms.
(16) Install timing case cover.
(17) Install cylinder head covers.
(18) Install intake manifold.
(19) Install the engine cover.
(20) Install the A/C Condenser (if equipped)
(21) Install the radiator. Refer to Group 7, Cooling
for the correct procedures.
(22) Refill cooling system. Refer to Group 7, Cool-
ing for the correct procedures.
(23) Start engine check for leaks.CAMSHAFT BEARINGS
REMOVAL
NOTE: This procedure requires that the engine is
removed from the vehicle.
(1) With engine completely disassembled, drive out
rear cam bearing core plug.
(2) Install proper size adapters and horseshoe
washers (part of Camshaft Bearing Remover/Installer
Tool C-3132-A) at back of each bearing shell. Drive
out bearing shells (Fig. 62).
INSTALLATION
(1) Install new camshaft bearings with Camshaft
Bearing Remover/Installer Tool C-3132-A by sliding
the new camshaft bearing shell over proper adapter.
(2) Position rear bearing in the tool. Install horse-
shoe lock and by reversing removal procedure, care-
fully drive bearing shell into place.
(3) Install remaining bearings in the same man-
ner. Bearings must be carefully aligned to bring oil
holes into full register with oil passages from the
main bearing. If the camshaft bearing shell oil holes
are not in exact alignment, remove and install them
correctly. Install a new core hole plug at the rear of
camshaft.Be sure this plug does not leak.
DISTRIBUTOR DRIVE SHAFT BUSHING
REMOVAL
(1) Remove distributor, refer to Group 8D, Ignition
Systems for the proper procedure.
(2) Remove the intake manifold. Refer to Intake
Manifold in this section for correct procedure.
(3) Insert Distributor Drive Shaft Bushing Puller
Tool C-3052 into old bushing and thread down until a
tight fit is obtained (Fig. 63).
Fig. 61 Alignment of Timing Marks
1 ± TIMING MARKS
Fig. 62 Camshaft Bearings Removal/Installation with
Tool C-3132-A
1 ± SPECIAL TOOL C-3132±A
2 ± MAIN BEARING OIL HOLE
9 - 172 5.9L ENGINEDN
REMOVAL AND INSTALLATION (Continued)