
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 (2) Install Oil Pressure Line and Gauge Tool
C-3292. Start engine and record pressure. Refer to
Oil Pressure in Engine Specifications for the proper
pressures.
SERVICE PROCEDURES
FORM-IN-PLACE GASKETS
There are several places where form-in-place gas-
kets are used on the engine.DO NOT use form-in-
place gasket material unless specified.Care
must be taken when applying form-in-place gaskets.
Bead size, continuity and location are of great impor-
tance. Too thin a bead can result in leakage while too
much can result in spill-over. A continuous bead of
the proper width is essential to obtain a leak-free
joint.
Two types of form-in-place gasket materials are
used in the engine area (Mopar Silicone Rubber
Adhesive Sealant and Mopar Gasket Maker). Each
have different properties and cannot be used inter-
changeably.
MOPAR SILICONE RUBBER ADHESIVE SEALANT
Mopar Silicone Rubber Adhesive Sealant, normally
black in color, is available in 3 ounce tubes. Moisture
in the air causes the sealant material to cure. This
material is normally used on flexible metal flanges.
It has a shelf life of a year and will not properly cure
if over aged. Always inspect the package for the expi-
ration date before use.
MOPAR GASKET MAKER
Mopar Gasket Maker, normally red in color, is
available in 6 cc tubes. This anaerobic type gasket
material cures in the absence of air when squeezed
between smooth machined metallic surfaces. It will
not cure if left in the uncovered tube. DO NOT use
on flexible metal flanges.
SURFACE PREPARATION
Parts assembled with form-in-place gaskets may be
disassembled without unusual effort. In some
instances, it may be necessary to lightly tap the part
with a mallet or other suitable tool to break the seal
between the mating surfaces. A flat gasket scraper
may also be lightly tapped into the joint but care
must be taken not to damage the mating surfaces.
Scrape or wire brush all gasket surfaces to remove
all loose material. Inspect stamped parts to ensure
gasket rails are flat. Flatten rails with a hammer on
a flat plate, if required. Gasket surfaces must be free
of oil and dirt. Make sure the old gasket material is
removed from blind attaching holes.
GASKET APPLICATION
Assembling parts using a form-in-place gasket
requires care.
Mopar Silicone Rubber Adhesive Sealant should be
applied in a continuous bead approximately 3 mm
(0.12 inch) in diameter. All mounting holes must be
circled. For corner sealing,a3or6mm(1/8 or 1/4
inch) drop is placed in the center of the gasket con-
tact area. Uncured sealant may be removed with a
shop towel. Components should be torqued in place
while the sealant is still wet to the touch (within 10
minutes). The use of a locating dowel is recom-
mended during assembly to prevent smearing the
material off location.
Mopar Gasket Maker should be applied sparingly
to one gasket surface. The sealant diameter should
be 1.00 mm (0.04 inch) or less. Be certain the mate-
rial 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 the material off location.
ENGINE PERFORMANCE
It is important that the vehicle is operating to its
optimum performance level to maintain fuel economy
and the lowest emission levels. If vehicle is not oper-
ating to these standards, refer to Engine Diagnosis
outlined in this section. The following procedures can
assist in achieving the proper engine diagnosis.
(1) Test cranking amperage draw. Refer to Electri-
cal Group 8B, Cold Cranking Test.
Fig. 11 Leak-Down Tester
1 ± POINTER
2 ± WEIGHTED ARM
3 ± RAM
4 ± CUP
5 ± HANDLE
6 ± PUSH ROD
DN5.9L ENGINE 9 - 149
DIAGNOSIS AND TESTING (Continued)

Downloaded from www.Manualslib.com manuals search engine (2) Check intake manifold bolt torque.
(3) Perform cylinder compression test. Refer to
Cylinder Compression Pressure Test in the Engine
Diagnosis area of this section.
(4) Clean or replace spark plugs as necessary and
adjust gap as specified in Electrical Group 8D.
Tighten to specifications.
(5) Test resistance of spark plug cables. Refer to
Electrical Group 8D, Spark Plug Cables.
(6) Inspect the primary wires. Test coil output volt-
age and primary resistance. Replace parts as neces-
sary. Refer to Electrical Group 8D, for specifications.
(7) Test fuel pump for pressure. Refer to Group 14,
Fuel System Specifications.
(8) The air filter elements should be replaced as
specified in Lubrication and Maintenance, Group 0.
(9) Inspect crankcase ventilation system as out
lined in Group 0, Lubrication and Maintenance. For
emission controls see Group 25, Emission Controls
for service procedures.
(10) Road test vehicle as a final test.
ENGINE OIL
WARNING: NEW OR USED ENGINE OIL CAN BE
IRRITATING TO THE SKIN. AVOID PROLONGED OR
REPEATED SKIN CONTACT WITH ENGINE OIL.
CONTAMINANTS IN USED ENGINE OIL, CAUSED BY
INTERNAL COMBUSTION, CAN BE HAZARDOUS TO
YOUR HEALTH. THOROUGHLY WASH EXPOSED
SKIN WITH SOAP AND WATER. DO NOT WASH
SKIN WITH GASOLINE, DIESEL FUEL, THINNER, OR
SOLVENTS, HEALTH PROBLEMS CAN RESULT. DO
NOT POLLUTE, DISPOSE OF USED ENGINE OIL
PROPERLY.
ENGINE OIL SPECIFICATION
CAUTION: Do not use non-detergent or straight
mineral oil when adding or changing crankcase
lubricant. Engine failure can result.
API SERVICE GRADE CERTIFIED
In gasoline engines, use an engine oil that is API
Service Grade Certified (Fig. 12). Standard engine oil
identification notations have been adopted to aid in
the proper selection of engine oil. The identifying
notations are located on the label of engine oil plastic
bottles and the top of engine oil cans. MOPAR only
provides engine oil that conforms to this certification.
SAE VISCOSITY
An SAE viscosity grade is used to specify the vis-
cosity of engine oil. SAE 10W-30 specifies a multiple
viscosity engine oil. These are specified with a dualSAE viscosity grade which indicates the cold-to-hot
temperature viscosity range. When choosing an
engine oil, consider the range of temperatures the
vehicle will be operated in before the next oil change.
Select an engine oil that is best suited to your area's
particular ambient temperature range and variation
(Fig. 13).
ENERGY CONSERVING OIL
An Energy Conserving type oil is recommended for
gasoline engines. The designation of ENERGY CON-
SERVING is located on the label of an engine oil con-
tainer.
OIL LEVEL INDICATOR (DIPSTICK)
The engine oil level indicator is located at the right
front of the engine, left of the generator on 5.9L
engines (Fig. 14).
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil,
oil foaming and oil pressure loss can result.
To ensure proper lubrication of an engine, the
engine oil must be maintained at an acceptable level.
The acceptable levels are indicated between the ADD
and SAFE marks on the engine oil dipstick.
(1) Position vehicle on level surface.
Fig. 12 Engine Oil Container Standard Notations
Fig. 13 Temperature/Engine Oil Viscosity
Recommendation
9 - 150 5.9L ENGINEDN
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine (2) With engine OFF, allow approximately ten min-
utes for oil to settle to bottom of crankcase, remove
engine oil dipstick.
(3) Wipe dipstick clean.
(4) Install dipstick and verify it is seated in the
tube.
(5) Remove dipstick, with handle held above the
tip, take oil level reading.
(6) Add oil only if level is below the ADD mark on
dipstick.
ENGINE OIL CHANGE
Change engine oil at mileage and time intervals
described in the Maintenance Schedule. This infor-
mation can be found in your owner's manual.
TO CHANGE ENGINE OIL
Run engine until achieving normal operating tem-
perature.
(1) Position the vehicle on a level surface and turn
engine off.
(2) Hoist and support vehicle on safety stands.
Refer to Hoisting and Jacking Recommendations.
(3) Remove oil fill cap.
(4) Place a suitable drain pan under crankcase
drain.
(5) Remove drain plug from crankcase and allow
oil to drain into pan. Inspect drain plug threads for
stretching or other damage. Replace drain plug and
gasket if damaged.
(6) Install drain plug in crankcase.(7) Lower vehicle and fill crankcase with specified
type and amount of engine oil described in this sec-
tion.
(8) Install oil fill cap.
(9) Start engine and inspect for leaks.
(10) Stop engine and inspect oil level.
ENGINE OIL FILTER CHANGE
FILTER SPECIFICATION
All engines are equipped with a high quality full-
flow, disposable type oil filter. DaimlerChrysler Cor-
poration recommends a Mopar or equivalent oil filter
be used.
OIL FILTER REMOVAL
(1) Position a drain pan under the oil filter.
(2) Using a suitable oil filter wrench loosen filter.
(3) Rotate the oil filter counterclockwise to remove
it from the cylinder block oil filter boss (Fig. 15).
(4) When filter separates from adapter nipple, tip
gasket end upward to minimize oil spill. Remove fil-
ter from vehicle.
(5) With a wiping cloth, clean the gasket sealing
surface (Fig. 16) of oil and grime.
OIL FILTER INSTALLATION
(1) Lightly lubricate oil filter gasket with engine
oil or chassis grease.
(2) Thread filter onto adapter nipple. When gasket
makes contact with sealing surface, (Fig. 16) hand
tighten filter one full turn, do not over tighten.
(3) Add oil, verify crankcase oil level and start
engine. Inspect for oil leaks.
REPAIR DAMAGED OR WORN THREADS
CAUTION: Be sure that the tapped holes maintain
the original center line.
Fig. 14 Engine Oil Dipstick LocationÐ5.9L Engines
1 ± CYLINDER HEAD COVER
2 ± ENGINE OIL FILL-HOLE CAP
3 ± DIPSTICK
4 ± ENGINE OIL FILTER
5 ± FILTER BOSS
Fig. 15 Oil Filter RemovalÐTypical
1 ± ENGINE OIL FILTER
2 ± OIL FILTER WRENCH
DN5.9L ENGINE 9 - 151
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine Damaged or worn threads can be repaired. Essen-
tially, this repair consists of:
²Drilling out worn or damaged threads.
²Tapping the hole with a special Heli-Coil Tap, or
equivalent.
²Installing an insert into the tapped hole to bring
the hole back to its original thread size.
CYLINDER BOREÐHONING
Before honing, stuff plenty of clean shop towels
under the bores and over the crankshaft to keep
abrasive materials from entering the crankshaft
area.
(1) Used carefully, the Cylinder Bore Sizing Hone
C-823, equipped with 220 grit stones, is the best tool
for this job. In addition to deglazing, it will reduce
taper and out-of-round, as well as removing light
scuffing, scoring and scratches. Usually, a few strokes
will clean up a bore and maintain the required lim-
its.
CAUTION: DO NOT use rigid type hones to remove
cylinder wall glaze.
(2) Deglazing of the cylinder walls may be done if
the cylinder bore is straight and round. Use a cylin-
der surfacing hone, Honing Tool C-3501, equipped
with 280 grit stones (C-3501-3810). about 20-60
strokes, depending on the bore condition, will be suf-
ficient to provide a satisfactory surface. Using honing
oil C-3501-3880, or a light honing oil, available from
major oil distributors.
CAUTION: DO NOT use engine or transmission oil,
mineral spirits, or kerosene.
(3) Honing should be done by moving the hone up
and down fast enough to get a crosshatch pattern.The hone marks should INTERSECT at 50É to 60É
for proper seating of rings (Fig. 17).
(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 50É to 60É
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.
Fig. 16 Oil Filter Sealing SurfaceÐTypical
1 ± SEALING SURFACE
2 ± RUBBER GASKET
3 ± OIL FILTER
Fig. 17 Cylinder Bore Crosshatch Pattern
1 ± CROSSHATCH PATTERN
2 ± INTERSECT ANGLE
9 - 152 5.9L ENGINEDN
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine (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 10É before top dead center to 2É 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:
²Check sprocket index marks.
²Inspect timing chain for wear.
²Check 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. 18). The special
sleeve places the valve at the correct height for
checking with a dial indicator.
(2) Attach Dial Indicator Tool C-3339 to cylinder
head and set it at right angle of valve stem being
measured (Fig. 19).
(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).
Fig. 18 Positioning Valve with Tool C-3973
1 ± VALVE
2 ± SPACER TOOL
Fig. 19 Measuring Valve Guide Wear
1 ± VALVE
2 ± SPECIAL TOOL C-3339
DN5.9L ENGINE 9 - 153
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine Use a 2 step procedure so the valve guides are
reamed true in relation to the valve seat:
²Step 1ÐReam to 0.0763 mm (0.003 inch).
²Step 2ÐReam to 0.381 mm (0.015 inch).
REFACING VALVES AND VALVE SEATS
The intake and exhaust valves have a 43-1/4É to
43-3/4É face angle and a 44-1/4É to 44-3/4É seat angle
(Fig. 20).
VALVES
Inspect the remaining margin after the valves are
refaced (Fig. 21). 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. 22).
(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.
(3) Inspect the valve seat with Prussian blue to
determine where the valve contacts the seat. To do
this, coat valve seatLIGHTLYwith 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 15É stone. If the blue is transferred to bottom
edge of valve face raise valve seat with a 60É stone.
(4) When seat is properly positioned the width of
intake seats should be 1.016-1.524 mm (0.040-0.060
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. 20 Valve Face and Seat Angles
1 ± CONTACT POINT
VALVE FACE AND VALVE SEAT ANGLE CHART
ITEM DESCRIPTION SPECIFICATION
ASEAT 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.)
BFACE ANGLE
(INT. and EXT.) 43
1¤4É-433¤4É
CSEAT ANGLE
(INT. and EXT.) 44
1¤4É-443¤4É
DCONTACT
SURFACE Ð
Fig. 21 Intake and Exhaust Valves
1 ± MARGIN
2 ± VALVE SPRING RETAINER LOCK GROOVE
3 ± STEM
4±FACE
9 - 154 5.9L ENGINEDN
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine 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. 23). 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 camshaftsprocket 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. 24).
(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.
Fig. 22 Refacing Valve Seats
1±STONE
2 ± PILOT
3 ± VALVE SEAT
4 ± SHROUD
Fig. 23 Testing Valve Spring for Compressed
Length
1 ± TORQUE WRENCH
2 ± VALVE SPRING TESTER
Fig. 24 Measuring Timing Chain Wear and Stretch
1 ± TORQUE WRENCH
2 ± 3.175 MM
(0.125 IN.)
DN5.9L ENGINE 9 - 155
SERVICE PROCEDURES (Continued)