
Total runout should not exceed. 0.051 mm (0.002
inch.) (total indicator reading).
(5) 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 top edge of the valve face, lower valve seat
with a 15 degrees stone. If the blue is transferred to
the bottom edge of valve face raise valve seat with a
65 degrees stone.
²Intake valve seat diameter is 33 mm (1.299 in.)
²Exhaust valve seat diameter is 28 mm (1.102
in.)
(6) Valve seats which are worn or burned can be
reworked, provided that correct angle and seat width
are maintained. The intake valve seat must be ser-
viced when the valve seat width is 2.0 mm (0.079 in.)
or greater. The exhaust valve seat must be serviced
when the valve seat width is 2.5 mm (0.098 in.) or
greater. Otherwise the cylinder head must be
replaced.
(7) When seat is properly positioned the width of
intake and exhaust seats should be 0.75 to 1.25 mm
(0.030 to 0.049 in.) (Fig. 91).
(8) Check valve tip to spring seat dimensions A
after grinding the valve seats or faces. Grind valve
tip to 43.51 - 44.57 mm (1.71 - 1.75 in.) for exhaust
valve and 45.01 - 46.07 mm (1.77 - 1.81 in.) for
intake valve over spring seat when installed in the
head (Fig. 92). The valve tip chamfer may need to be
reground to prevent seal damage when the valve is
installed.
CLEANING
Clean all valve guides, valves and valve spring
assemblies thoroughly with suitable cleaning solution
before reassembling.
VALVE INSTALLATION
(1) Coat valve stems with clean engine oil and
insert in cylinder head.
(2) Install new valve stem seals on all valves using
a valve stem seal tool (Fig. 93). The valve stem seals
should be pushed firmly and squarely over valve
guide.
CAUTION: If oversize valves are used, there is only
one oversize valve available. The same stem seal is
used on both the standard and oversize valve.
(3) Install valve springs and retainers. Compress
valve springs only enough to install locks, taking
care not to misalign the direction of compression.
Nicked valve stems may result from misalignment of
the valve spring compressor.
VALVE SPECIFICATION CHART
Face Angle
Intake and
Exhaust:45 - 45 1/2É
Head Diameter
Intake: 33.12 - 33.37 mm (1.303 - 1.313 in.)
Exhaust: 28.57 - 28.83 mm (1.124 - 1.135 in.)
Length (Overall)
Intake: 114.69 - 115.19 mm (4.515 - 4.535 in.)
Exhaust: 116.94 - 117.44 mm (4.603 - 4.623 in.)
Stem Diameter
Intake: 5.934 - 5.952 mm (0.2337 - 0.2344 in.)
Exhaust: 5.906 - 5.924 mm (0.2326 - 0.2333 in.)
Valve Margin
Intake: 1.15 - 1.48 mm (0.0452 - 0.0582 in.)
Exhaust: 1.475 - 1.805 mm (0.0580 - 0.0710 in.)
Fig. 91 Valve Seat Refacing
Fig. 92 Spring Installed Height and Valve Tip to
Spring Seat Dimensions
NS/GSENGINE 9 - 31
DISASSEMBLY AND ASSEMBLY (Continued)

CAUTION: When depressing the valve spring
retainers with valve spring compressor the locks
can become dislocated. Check to make sure both
locks are in their correct location after removing
tool.
(4) Check the valve spring installed height B after
refacing the valve and seat (Fig. 92). Make sure mea-
surements are taken from top of spring seat to the
bottom surface of spring retainer. If height is greater
than 40.18 mm (1.58 in.), install a 0.762 mm (0.030
in.) spacer under the valve spring seat to bring
spring height back within specification.
(5) Install rocker arm shafts as previously
described in this section.
(6) Checking dry lash. Dry lash is the amount of
clearance that exists between the base circle of an
installed cam and the rocker arm roller when the
adjuster is drained of oil and completely collapsed.
Specified dry lash is 1.17 mm (0.046 in.) for intake
and 1.28 mm (0.050 in.) for exhaust. After performing
dry lash check, refill adjuster with oil and allow 10
minutes for adjuster/s to bleed down before rotating
cam.
CLEANING AND INSPECTION
CYLINDER HEAD AND CAMSHAFT JOURNALS
INSPECTING CYLINDER HEAD
Cylinder head must be flat within 0.1 mm (0.004
inch) (Fig. 94).
Inspect cylinder head camshaft bearings for wear.
Check camshaft journals for scratches and worn
areas. If light scratches are present, they may be
removed with 400 grit sand paper. If deep scratches
are present, replace the camshaft and check the cyl-
inder head for damage. Replace the cylinder head if
worn or damaged. Check the lobes for pitting and
wear. If the lobes show signs of wear, check the cor-
responding rocker arm roller for wear or damage.Replace rocker arm/hydraulic lash adjuster if worn or
damaged. If lobes show signs of pitting on the nose,
flank or base circle; replace the camshaft.
CLEANING
Remove all gasket material from cylinder head and
block. Be careful not to gouge or scratch the alumi-
num head sealing surface.
OIL PUMP
(1) Clean all parts thoroughly. Mating surface of
the oil pump should be smooth. Replace pump cover
if scratched or grooved.
(2) Lay a straightedge across the pump cover sur-
face (Fig. 95). If a 0.076 mm (0.003 inch.) feeler
gauge can be inserted between cover and straight
edge, cover should be replaced.
(3) Measure thickness and diameter of outer rotor.
If outer rotor thickness measures 7.64 mm (0.301
inch.) or less (Fig. 96), or if the diameter is 79.95 mm
(3.148 inches) or less, replace outer rotor.
Fig. 93 Valve Stem Oil Seal Tool
Fig. 94 Checking Cylinder Head Flatness
Fig. 95 Checking Oil Pump Cover Flatness
9 - 32 ENGINENS/GS
DISASSEMBLY AND ASSEMBLY (Continued)

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 3.5 bars to 5.0 bars at 4000 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 2 condi-
tions 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.
OIL LEVEL 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 cre-
ate 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 1 tappet will be
noisy. When oil level and leaks have been corrected,
operate the engine at fast idle. Run engine for a suf-
ficient 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 the
plunger partially sticking in the tappet body cylinder.
The tappet should be replaced. A heavy click iscaused by a tappet check valve not seating or by for-
eign particles becoming wedged between the plunger
and the tappet body. This will cause the plunger to
stick in the down position. This heavy click will be
accompanied by excessive clearance between the
valve stem and rocker arm as valve closes. In either
case, tappet assembly should be removed for inspec-
tion and cleaning.
(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. In general, if more than one tappet
seems to be noisy, its probably not the tappets.
SERVICE PROCEDURES
CHECKING OIL LEVEL
To assure proper engine lubrication, the engine oil
must be maintained at the correct level. Check the
oil level at regular intervals, such as every fuel stop.
The best time to check the oil level is about 5 min-
utes after a fully warmed-up engine is shut off, or
before starting the vehicle after it has sat overnight.
Checking the oil while the vehicle is on level
ground, will improve the accuracy of the oil level
readings (Fig. 4).
CHANGING ENGINE OIL AND FILTER
Change engine oil and filter at mileage and time
intervals described in the Maintenance Schedule.
Fig. 4 Checking Engine Oil
NS/GSENGINE 9 - 47
DIAGNOSIS AND TESTING (Continued)

ENGINE OIL CHANGE
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. CONTACT YOUR DEALER OR GOVERN-
MENT AGENCY FOR LOCATION OF COLLECTION
CENTER IN YOUR AREA.
Run engine until achieving normal operating tem-
perature.
(1) Position the vehicle on a level surface and turn
engine off.
(2) Remove oil fill cap.
(3) Hoist vehicle. Refer to Hoisting and Jacking
Recommendations.
(4) Place a suitable drain pan under crankcase
drain.
(5) Remove drain plug from crankcase and allow
oil to drain into pan (Fig. 5). Inspect drain plug
threads for stretching or other damage. Replace
drain plug if damaged.
(6) Install drain plug in crankcase.
(7) Lower vehicle and fill crankcase with specified
type and amount of engine oil.
(8) Install oil fill cap.
(9) Start engine and inspect for leaks.
(10) Stop engine and inspect oil level.
ENGINE OIL
ENGINE OIL QUALITY
Use only oils conforming to API (American Petro-
leum Institute) quality SG/CD, or CCMC G4. Use
only Diesel engine oil meeting standardMIL-2104C
or API service classificationSG/CD or CCMM PD1.
OIL VISCOSITY
Grade 15W-40 is recommended for temperatures
between +35ÉC to ±10ÉC (95ÉF to 14ÉF). Low viscosity
oils must have the proper API quality or the CCMC
G5 designation. Low viscosity oils are preferred when
minimum temperatures consistently fall below ±12ÉC
(10ÉF).
ENGINE OIL FILTER CHANGE
(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 oil filter base (Fig. 6).
(4) When filter separates from base, tip gasket end
upward to minimize oil spill. Remove filter from vehi-
cle.
(5) With a cloth, wipe clean the gasket sealing sur-
face of oil and grime.
OIL FILTER INSTALLATION
(1) Lightly lubricate oil filter gasket with engine
oil.
(2) Thread filter onto the base. When gasket
makes contact with sealing surface, hand tighten fil-
ter one full turn, do not over tighten.
Fig. 5 Oil Drain Plug
Fig. 6 Oil Filter
9 - 48 ENGINENS/GS
SERVICE PROCEDURES (Continued)

(6) Refer to crankshaft main bearing Installation if
not in specification.
NOTE: If engine is disassembled refer to Crank-
shaft Main Bearing Removal and Installation for this
procedure.
REMOVAL AND INSTALLATION
ENGINE MOUNTÐFRONT
(1) Disconnect battery.
(2) Remove lower air dam at front fascia.
(3) Remove the bolts holding tow bracket and front
mount to the lower crossmember.(4) Remove thru bolt in engine mount (Fig. 14).
Remove mount.
(5) Reverse removal procedure for installation.
(6) Torque engine mount thru bolt to 65 N´m (48
ft. lbs.)
(7) Torque crossmember bolts for tow bracket and
engine mount to 54 N´m (40 ft. lbs.)
ENGINE MOUNTÐRIGHT
(1) Remove the right engine mount top support
bracket bolt (Fig. 15).
(2) Remove the load on the engine motor mounts
by carefully supporting the engine and transmission
assembly with a floor jack.
(3) Remove the engine mount to frame bolts.
(4) Remove the thru bolt from the mount assembly.
Remove insulator
(5) If replaceing or removing right engine mount
bracket the torque on the mounting bolts is 40 N´m
(30 ft. lbs.)
(6) Reverse removal procedure for installation.
(7) Torque engine mount top bolt (Vertical) to 101
N´m (75 ft. lbs.)
(8) Torque engine mount thru bolt (Horizontal) to
145 N´m (107 ft. lbs.)
(9) Torque engine mount to frame bolts to 68 N´m
(50 ft. lbs.)
MOUNTÐLEFT SIDE
(1) Raise vehicle on hoist and remove left front
wheel.
(2) Remove inner splash shield.
(3) Support the transmission with a transmission
jack.
(4) Remove the insulator thru bolt from the mount
(Fig. 16).
(5) Remove the transmission mount bolts and
remove mount. It may be necessary to lower trans-
mission slightly to remove mount.
(6) Reverse removal procedure for installation.
(7) Install mount. Torque transmission mount bolts
to 54 N´m (40 ft. lbs.).
(8) Align mount into frame bracket with transmis-
sion jack, install thru bolt. Torque thru bolt to 71
N´m (53 ft. lbs.).
Fig. 12 Piston Ring Side Clearance
Fig. 13 Measuring Crankshaft End Play
Fig. 14 Front Engine Mount and Tow Bracket
NS/GSENGINE 9 - 51
SERVICE PROCEDURES (Continued)

ENGINE ASSEMBLY
REMOVAL
(1) Disconnect the battery.
(2) Remove the air cleaner assembly and inlet
hose.
(3) Remove both hoses at intercooler and engine.
(4) Disconnect EGR vacuum hose.
(5) Disconnect brake booster vacuum hose.
(6) Disconnect oil pressure switch connector (Fig.
19).
(7) Disconnect Wiring harness bracket at transaxle
shift tower.
(8) Disconnect transaxle wiring at speed sensor,
crank sensor, and backup light switch.
(9) Remove both transmission shift cables at trans-
mission.
(10) Remove negative battery cable at cylinder
block (Fig. 19).
(11) Remove oil separator.
(12) Remove connectors at coolant temperature
sensor and A/C compressor.
(13) Disconnect fuel injection pump wiring connec-
tors (Fig. 19).
(14) Disconnect glow plug connectors.
(15) Disconnect electrical connector at number 1
fuel injector.
(16) Raise vehicle on hoist.
(17) Remove right side splash shield (Fig. 20).
WARNING: THE COOLANT IN A RECENTLY OPER-
ATED ENGINE IS HOT AND PRESSURIZED. USE
CARE TO PREVENT SCALDING BY HOT COOLANT.CAREFULLY RELEASE THE PRESSURE BEFORE
REMOVING THE RADIATOR DRAIN COCK AND CAP.
(18) Drain the cooling system (refer to Group 7,
Cooling).
(19) Lower vehicle.
(20) Remove Coolant pressure bottle and discon-
nect low coolant level sensor.
(21) Disconnect both heater hoses.
(22) Remove the lower radiator hose.
(23) Remove the upper radiator hose.
(24) Remove fuel line at injector pump and cap.
(25) Remove power steering reservoir and reposi-
tion.
(26) Remove upper radiator crossmember.
(27) Disconnect cooling fan module connector.
Fig. 18 Shift Cables at Rear MountFig. 19 Component Locations
Fig. 20 Right Side Splash Shield
NS/GSENGINE 9 - 53
REMOVAL AND INSTALLATION (Continued)

retainer and plunger spring. Check valve could be
flat or ball.
Assemble tappets in reverse order.
CLEANING AND INSPECTION
CYLINDER HEAD COVERS
Remove any original sealer from the cover sealing
surface of the engine cylinder head.
Remove all residue from the sealing surface using
a clean, dry cloth.
ROCKER ARMS AND PUSH RODS
CLEANING
Clean all the components (Fig. 69) with cleaning
solvent.
Use compressed air to blow out the oil passages in
the rocker arms and push rods.
INSPECTION
Inspect the pivot surface area of each rocker arm.
Replace any that are scuffed, pitted, cracked or
excessively worn.
Inspect the valve stem tip contact surface of each
rocker arm and replace any rocker arm that is deeply
pitted.
Inspect each push rod end for excessive wear and
replace as required. If any push rod is excessively
worn because of lack of oil, replace it and inspect the
corresponding hydraulic tappet for excessive wear.
Inspect the push rods for straightness by rolling
them on a flat surface or by shining a light between
the push rod and the flat surface.
A wear pattern along the length of the push rod is
not normal. Inspect the engine cylinder head for
obstruction if this condition exists.
Fig. 66 Liner Clamp Location
Fig. 67 Flywheel
Fig. 68 Crankshaft Seal
9 - 74 ENGINENS/GS
DISASSEMBLY AND ASSEMBLY (Continued)

(3.6196-3.6200 in.). Maximum wear limit .05mm
(.0019 in.).
(2) Check piston pin bores in piston for roundness.
Make 3 checks at 120É intervals. Maximum out of
roundness .05mm (.0019in.).
(3) The piston diameter should be measured
approximately 15 mm (.590 in.) up from the base.
(4) Skirt wear should not exceed 0.1 mm (.00039
in.).
(5) The clearance between the cylinder liner and
piston should not exceed 0.25 mm (.0009 in.).
(6) Make sure the weight of the pistons does not
differ by more than 5 g.
CONNECTING ROD
(1) Assemble bearing shells and bearing caps to
their respective connecting rods ensuring that the
serrations on the cap and reference marks are
aligned.
(2) Tighten bearing cap bolts to 29 N´m (21 ft. lbs.)
plus 60É.
(3) Check and record internal diameter of crank
end of connecting rod.
Note: When changing connecting rods, all four
must have the same weight and be stamped with the
same number.Replacement connecting rods will
only be supplied in sets of four.
(4) Connecting rods are supplied in sets of four
since they all must be of the same weight category.
Max allowable weight difference is 18 gr.NOTE:On
one side of the big end of the con-rod there is a two-
digit number which refers to the weight category. On
the other side of the big end there is a four digitnumber on both the rod and the cap. These numbers
must both face the camshaft as well as the recess on
the piston crown (Fig. 76). Lightly heat the piston in
oven. Insert piston pin in position and secure it with
provided snap rings.The Four digit numbers
marked on con rod big end and rod cap must
be on the same side as the camshaft (Fig. 76).
After having coated threads with Molyguard, tighten
con rod bolts to 29 N´m (21 ft. lbs.) plus 60É.
PISTON PIN
(1) Measure the diameter of piston pin in the cen-
ter and both ends (Fig. 77).
(2) Piston pin diameter is 29.990 to 29.996mm
(1.1807 to 1.1809 in.).
CRANKSHAFT
CRANKSHAFT JOURNALS
(1) Using a micrometer, measure and record crank-
shaft connecting rod journals, take reading of each
journal 120É apart. Crankshaft journal diameter is
53.84 to 53.955mm (2.1196 to 2.1242 in.).
(2) Crankshaft journals worn beyond limits or
show signs of out of roundness must be reground or
replaced. Minimum reground diameter is 53.69mm
(2.1137 in.).
BEARING-TO-JOURNAL CLEARANCE
Compare internal diameters of connecting rod with
crankshaft journal diameter. Maximum clearance
between connecting rod and crankshaft journals .022
to .076mm (.0008 to .0029 in.) (Fig. 78).
CRANKSHAFT MAIN BEARING
INSPECTION
(1) Fit main bearing carriers together and torque
to 42 N´m (31 ft. lbs.)
(2) Check internal diameter of bearings.
Fig. 75 Checking Rotor Clearance
Fig. 76 Connecting Rod Identification
NS/GSENGINE 9 - 77
CLEANING AND INSPECTION (Continued)