Dodge Durango (DN). Manual — part 441
(4) A controlled hone motor speed between 200 and
300 RPM is necessary to obtain the proper cross-
hatch angle. The number of up and down strokes per
minute can be regulated to get the desired 50° to 60°
angle. Faster up and down strokes increase the cross-
hatch angle.
(5) After honing, it is necessary that the block be
cleaned to remove all traces of abrasive. Use a brush
to wash parts with a solution of hot water and deter-
gent. Dry parts thoroughly. Use a clean, white, lint-
free cloth to check that the bore is clean. Oil the
bores after cleaning to prevent rusting.
HYDROSTATIC LOCK
When an engine is suspected of hydrostatic lock
(regardless of what caused the problem), follow the
steps below.
(1) Perform the Fuel Pressure Release Procedure
(refer to Group 14, Fuel System).
(2) Disconnect the battery negative cable.
(3) Inspect
air
cleaner,
induction
system
and
intake manifold to ensure system is dry and clear of
foreign material.
(4) Place a shop towel around the spark plugs to
catch any fluid that may possibly be under pressure
in the cylinder head. Remove the plugs from the
engine.
CAUTION: DO NOT use the starter motor to rotate
the crankshaft. Severe damage could occur.
(5) With all spark plugs removed, rotate the crank-
shaft using a breaker bar and socket.
(6) Identify the fluid in the cylinders (i.e. coolant,
fuel, oil, etc.).
(7) Make sure all fluid has been removed from the
cylinders.
(8) Repair engine or components as necessary to
prevent this problem from occurring again.
(9) Squirt engine oil into the cylinders to lubricate
the walls. This will prevent damage on restart.
(10) Install new spark plugs.
(11) Drain engine oil. Remove and discard the oil
filter.
(12) Install the drain plug. Tighten the plug to 34
N·m (25 ft. lbs.) torque.
(13) Install a new oil filter.
(14) Fill
engine
crankcase
with
the
specified
amount and grade of oil.
(15) Connect the negative cable to the battery.
(16) Start the engine and check for any leaks.
VALVE TIMING
(1) Turn crankshaft until the No.6 exhaust valve is
closing and No.6 intake valve is opening.
(2) Insert a 6.350 mm (1/4 inch) spacer between
rocker arm pad and stem tip of No.1 intake valve.
Allow spring load to bleed tappet down giving in
effect a solid tappet.
(3) Install a dial indicator so plunger contacts
valve spring retainer as nearly perpendicular as pos-
sible. Zero the indicator.
(4) Rotate the crankshaft clockwise (normal run-
ning direction) until the valve has lifted 0.863 mm
(0.034 inch). The timing of the crankshaft should
now read from 10° before top dead center to 2° after
top dead center. Remove spacer.
CAUTION: DO NOT turn crankshaft any further
clockwise as valve spring might bottom and result
in serious damage.
If reading is not within specified limits:
• Check sprocket index marks.
• Inspect timing chain for wear.
• Check accuracy of DC mark on timing indicator.
VALVE SERVICE
VALVE CLEANING
Clean valves thoroughly. Discard burned, warped
and cracked valves.
Remove carbon and varnish deposits from inside of
valve guides with a reliable guide cleaner.
VALVE INSPECTION
Measure valve stems for wear. If wear exceeds
0.051 mm (0.002 inch), replace the valve.
VALVE GUIDES
Measure valve stem guide clearance as follows:
(1) Install Valve Guide Sleeve Tool C-3973 over
valve stem and install valve (Fig. 17). The special
sleeve places the valve at the correct height for
checking with a dial indicator.
Fig. 17 Positioning Valve with Tool C-3973
1 – VALVE
2 – SPACER TOOL
DN
5.2L ENGINE
9 - 95
SERVICE PROCEDURES (Continued)
(2) Attach Dial Indicator Tool C-3339 to cylinder
head and set it at right angle of valve stem being
measured (Fig. 18).
(3) Move valve to and from the indicator. The total
dial indicator reading should not exceed 0.432 mm
(0.017 inch). Ream the guides for valves with over-
size stems if dial indicator reading is excessive or if
the stems are scuffed or scored.
Service valves with oversize stems are available as
shown below.
Slowly turn reamer by hand and clean guide thor-
oughly before installing new valve. Ream the valve
guides from standard to 0.381 mm (0.015 inch).
Use a 2 step procedure so the valve guides are
reamed true in relation to the valve seat:
• Step 1—Ream to 0.0763 mm (0.003 inch).
• Step 2—Ream to 0.381 mm (0.015 inch).
REFACING VALVES AND VALVE SEATS
The intake and exhaust valves have a 43-1/4° to
43-3/4° face angle and a 44-1/4° to 44-3/4° seat angle
(Fig. 19).
VALVES
Inspect the remaining margin after the valves are
refaced (Fig. 20). Valves with less than 1.190 mm
(0.047 inch) margin should be discarded.
VALVE SEATS
CAUTION: DO NOT un-shroud valves during valve
seat refacing (Fig. 21).
(1) When refacing valve seats, it is important that
the correct size valve guide pilot be used for reseat-
ing stones. A true and complete surface must be
obtained.
(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.
Fig. 18 Measuring Valve Guide Wear
1 – VALVE
2 – SPECIAL TOOL C-3339
REAMER SIZES
REAMER O/S
VALVE GUIDE SIZE
0.076 mm (0.003 in.)
8.026 - 8.052 mm
(0.316 - 0.317 in.)
0.381 mm (0.015 in.)
8.331 - 8.357 mm
(0.328 - 0.329 in.)
Fig. 19 Valve Face and Seat Angles
1 – CONTACT POINT
VALVE FACE AND VALVE SEAT ANGLE CHART
ITEM
DESCRIPTION
SPECIFICATION
A
SEAT WIDTH–
1.016 - 1.524 mm
INTAKE
(0.040 - 0.060 in.)
SEAT WIDTH–
1.524 - 2.032 mm
EXHAUST
(0.060 - 0.080 in.)
B
FACE ANGLE
(INT. and EXT.)
43
1
⁄
4
° - 43
3
⁄
4
°
C
SEAT ANGLE
(INT. and EXT.)
44
1
⁄
4
° - 44
3
⁄
4
°
D
CONTACT
SURFACE
—
9 - 96
5.2L ENGINE
DN
SERVICE PROCEDURES (Continued)
(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 15° stone. If the blue is transferred to bottom
edge of valve face raise valve seat with a 60° 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
Universal 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. 22). Place
spring over stud on the table and lift compressing
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 measurements
are indicated on the table for finer adjustments.
Refer to specifications to obtain specified height and
allowable tensions. Discard the springs that do not
meet specifications.
MEASURING TIMING CHAIN STRETCH
NOTE: To access timing chain Refer to Timing
Chain Cover in Removal and Installation Section.
(1) Place a scale next to the timing chain so that
any movement of the chain may be measured.
(2) Place a torque wrench and socket over cam-
shaft sprocket attaching bolt. Apply torque in the
direction of crankshaft rotation to take up slack; 41
N·m (30 ft. lbs.) torque with cylinder head installed
or 20 N·m (15 ft. lbs.) torque with cylinder head
removed. With a torque applied to the camshaft
Fig. 20 Intake and Exhaust Valves
1 – MARGIN
2 – VALVE SPRING RETAINER LOCK GROOVE
3 – STEM
4 – FACE
Fig. 21 Refacing Valve Seats
1 – STONE
2 – PILOT
3 – VALVE SEAT
4 – SHROUD
Fig. 22 Testing Valve Spring for Compressed
Length
1 – TORQUE WRENCH
2 – VALVE SPRING TESTER
DN
5.2L ENGINE
9 - 97
SERVICE PROCEDURES (Continued)
sprocket bolt, crankshaft should not be permitted to
move. It may be necessary to block the crankshaft to
prevent rotation.
(3) Hold a scale with dimensional reading even
with the edge of a chain link. With cylinder heads
installed, apply 14 N·m (30 ft. lbs.) torque in the
reverse direction. With the cylinder heads removed,
apply 20 N·m (15 ft. lbs.) torque in the reverse direc-
tion. Note the amount of chain movement (Fig. 23).
(4) Install a new timing chain, if its movement
exceeds 3.175 mm (1/8 inch).
(5) If chain is not satisfactory, remove camshaft
sprocket attaching bolt and remove timing chain with
crankshaft and camshaft sprockets.
(6) Place both camshaft sprocket and crankshaft
sprocket on the bench with timing marks on exact
imaginary center line through both camshaft and
crankshaft bores.
(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. 24).
(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.
PISTONS—FITTING
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
21°C (70°F).
Piston diameter should be measured at the top of
skirt, 90° 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, 21°C (70°F).
Check the pistons for taper and elliptical shape
before they are fitted into the cylinder bore (Fig. 25).
PISTON RINGS—FITTING
(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 compression
Fig. 23 Measuring Timing Chain Wear and Stretch
1 – TORQUE WRENCH
2 – 3.175 MM
(0.125 IN.)
Fig. 24 Alignment of Timing Marks
1 – TIMING MARKS
Fig. 25 Piston Measurements
1 – 49.53 mm
(1.95 IN.)
9 - 98
5.2L ENGINE
DN
SERVICE PROCEDURES (Continued)
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