CAUTION: Do not pry up on one side of the bed-
plate. Damage may occur to cylinder block and bed-
plate alignment.(7) Bedplate should be removed evenly from the
cylinder block dowel pins.
(8) Lift out crankshaft from cylinder block. Be sure
not to damage the main bearings or journals when
removing the crankshaft.
CRANKSHAFT MAIN BEARINGS LOCATION
The crankshaft is supported in five main bearings.
All upper bearing shells in the crankcase have oil
grooves. All lower bearing shells installed in the (bed-
plate) main bearing cap are plain. Crankshaft end
play is controlled by a flanged bearing on the number
three main bearing journal (Fig. 64).
NOTE: The upper and lower main Bearing shells
are Not interchangeable. The lower shells have a
revised tab to prevent improper installation.
CRANKSHAFT MAIN JOURNALS INSPECTION
The crankshaft journals should be checked for
excessive wear, taper and scoring. Limits of taper or
out-of-round on any crankshaft journals should be
held to .025 mm (.001 inch). Journal grinding should
not exceed .305 mm (.012 inch) under the standard
journal diameter. DO NOT grind thrust faces of
Number 3 main bearing. DO NOT nick crank pin or
bearing fillets. After grinding, remove rough edges
from crankshaft oil holes and clean out all passages.
CAUTION: With the nodular cast iron crankshafts
used it is important that the final paper or cloth pol-
ish after any journal regrind be in the same direc-
tion as normal rotation in the engine.
Upper and lower Number 3 bearing halves are
flanged to carry the crankshaft thrust loads and are
NOT interchangeable with any other bearing halves
in the engine (Fig. 64). All bearing cap bolts removed
during service procedures are to be cleaned and oiled
before installation. Bearing shells are available in
standard and the following undersized: 0.016 mm
(.0006 inch), .032 mm (.0012 inch), .250 mm (.010
inch). Never install an undersize bearing that will
reduce clearance below specifications.
INSTALLATION
(1) Install the main bearing shells with the lubri-
cation groove in the cylinder block. Install O-ring
into recess in the block (Fig. 65).
(2) Make certain oil holes in block line up with oil
hole in bearings and bearing tabs seat in the block
tab slots.
CAUTION: Do Not get oil on the bedplate mating
surface. It will affect the sealer ability to seal the
bedplate to cylinder block.
Fig. 61 Crankshaft Seal Special Tool 6926-2
Fig. 62 Rear Crankshaft SealÐInstallation
9 - 22 ENGINENS/GS
REMOVAL AND INSTALLATION (Continued)
(8) Install main bearing bedplate to engine block
bolts (1 thru 10) and torque each bolt to 81 N´m (60
ft. lbs.) in sequence shown in (Fig. 67).(9) Install main bearing bedplate to engine block
bolts (11 thru 20), with baffle studs in positions 12,
13 and 16 and torque each bolt to 30 N´m (22 ft. lbs.)
in sequence shown in (Fig. 67).
(10) After the main bearing bedplate is installed,
check the crankshaft turning torque. The turning
torque should not exceed 5.6 N´m (50 in. lbs.).
(11) Install oil pump. If crankshaft end play is to
be checked refer to service procedures in this section.
(12) Install crankshaft sprocket.
(13) Install oil filter adapter and filter.
(14) Install oil pan and collar. Refer to procedures
outlined in the section.
(15) Perform camshaft and crankshaft timing
relearn procedure as follows:
²Connect the DRB scan tool to the data link
(diagnostic) connector. This connector is located in
the passenger compartment; at the lower edge of
instrument panel; near the steering column.
²Turn the ignition switch on and access the ªmis-
cellaneousº screen.
²Select ªre-learn cam/crankº option and follow
directions on DRB screen.
OIL FILTER ADAPTER
REMOVE AND INSTALL
Ensure O-ring is in the groove on adapter. Align
roll pin into engine block and tighten assembly to 80
N´m (60 ft. lbs.) (Fig. 68).
OIL FILTER
REMOVE AND INSTALL
CAUTION: When servicing the oil filter (Fig. 69)
avoid deforming the filter, install tool band strap
against the seam at the base of the filter. The seam,
joining the can to the base is reinforced by the
base plate.
(1) Turn counterclockwise to remove.
(2) To install, lubricate new filter gasket. Check
filter mounting surface. The surface must be smooth,
flat and free of debris or old pieces of rubber. Screw
Fig. 65 Installing Main Bearing Upper Shell
Fig. 66 Main Bearing Caps/Bedplate Sealing
Fig. 67 Main Bearing Caps/Bedplate Torque
Sequence
Fig. 68 Engine Oil Filter Adapter to Engine Block
9 - 24 ENGINENS/GS
REMOVAL AND INSTALLATION (Continued)
INSTALLATION
(1) Install crankshaft damper using M12-1.75 x
150 mm bolt, washer, thrust bearing and nut from
Special Tool 6792. Install crankshaft damper bolt and
tighten to 142 N´m (105 ft. lbs.) (Fig. 84).
(2) Install accessory drive belts. Refer to Group 7,
Cooling System Accessory Drive section for proce-
dure.
DISASSEMBLY AND ASSEMBLY
OIL PUMP
(1) To remove the relief valve, proceed as follows:
(2) Remove the threaded plug and gasket from the
oil pump (Fig. 85).
CAUTION: Oil pump pressure relief valve must be
installed as shown in (Fig. 85) or serious damage
may occur.
(3) Remove spring and relief valve (Fig. 85).(4) Remove oil pump cover screws, and lift off
cover.
(5) Remove pump rotors.
(6) Wash all parts in a suitable solvent and inspect
carefully for damage or wear (Fig. 86).
VALVE SERVICE WITH THE CYLINDER HEAD
REMOVED
REMOVAL
(1) With cylinder head removed, compress valve
springs using Special Tool C-3422-B or equivalent.
(2) Remove valve retaining locks, valve spring
retainers, valve stem seals and valve springs.
(3) Before removing valves,remove any burrs
from valve stem lock grooves to prevent dam-
age to the valve guides.Identify valves to insure
installation in original location.
VALVE INSPECTION
(1) Clean valves thoroughly and discard burned,
warped and cracked valves.
(2) Measure valve stems for wear. Measure stem
about 60 mm beneath the valve lock grooves.
(3) If valve stems are worn more than 0.05 mm
(.002 in.), replace valve.
VALVE GUIDES
(1) Remove carbon and varnish deposits from
inside of valve guides with a reliable guide cleaner.
(2) Using a small hole gauge and a micrometer,
measure valve guides in 3 places top, middle and bot-
tom (Fig. 87). Refer to Valve Guide Specification
Chart for specifications. Replace guides if they are
not within specification.
(3) Check valve guide height (Fig. 88).
TESTING VALVE SPRINGS
(1) Whenever valves have been removed for inspec-
tion, reconditioning or replacement, valve springs
Fig. 84 Crankshaft DamperÐInstallation
Fig. 85 Oil Pressure Relief Valve
Fig. 86 Oil Pump
NS/GSENGINE 9 - 29
REMOVAL AND INSTALLATION (Continued)
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)
2.5L VM DIESEL
INDEX
page page
GENERAL INFORMATION
ENGINE IDENTIFICATION................ 41
GENERAL SPECIFICATION............... 40
DESCRIPTION AND OPERATION
LUBRICATION SYSTEM.................. 41
DIAGNOSIS AND TESTING
ENGINE DIAGNOSISÐMECHANICAL....... 44
ENGINE DIAGNOSISÐPERFORMANCE..... 43
HYDRAULIC TAPPETS................... 47
SERVICE PROCEDURES
CHANGING ENGINE OIL AND FILTER....... 47
CHECKING OIL LEVEL................... 47
CRANKSHAFT END PLAY................ 50
FITTING PISTON RING.................. 50
TIMING PROCEDURE................... 49
VALVE AND SEAT REFACING............. 49
REMOVAL AND INSTALLATION
CAMSHAFT........................... 62
CAMSHAFT BEARINGS.................. 63
CRANKSHAFT MAIN BEARINGS........... 63
CRANKSHAFTÐREMOVAL............... 72
CYLINDER HEAD....................... 55
CYLINDER HEAD COVER................ 54
CYLINDER LINER...................... 72
ENGINE ASSEMBLY..................... 53
ENGINE MOUNTÐFRONT................ 51
ENGINE MOUNTÐREAR................. 52
ENGINE MOUNTÐRIGHT................ 51
HYDRAULIC TAPPETS................... 60
INJECTION PUMP...................... 61
MOUNTÐLEFT SIDE.................... 51
OIL FILTER ADAPTER AND OIL COOLER.... 68
OILPAN .............................. 66OIL PUMP............................ 67
OIL PUMP PRESSURE RELIEF VALVE...... 67
PISTONS AND CONNECTING ROD......... 68
REAR CRANKSHAFT OIL SEAL............ 72
ROCKER ARMS AND PUSH RODS......... 54
TIMING GEAR COVER................... 61
TIMING GEAR COVER OIL SEAL........... 61
VACUUM PUMP........................ 68
VALVE SPRINGSÐCYLINDER HEAD NOT
REMOVED.......................... 55
VALVES AND VALVE SPRINGSÐHEAD OFF . . 60
VIBRATION DAMPER.................... 61
DISASSEMBLY AND ASSEMBLY
HYDRAULIC TAPPETS................... 73
CLEANING AND INSPECTION
CRANKSHAFT......................... 77
CRANKSHAFT MAIN BEARING............ 77
CYLINDER HEAD....................... 75
CYLINDER HEAD COVERS............... 74
CYLINDER LINER...................... 78
HYDRAULIC TAPPETS................... 76
OILPAN .............................. 78
OIL PUMP............................ 76
PISTON AND CONNECTING ROD.......... 76
ROCKER ARMS AND PUSH RODS......... 74
TIMING GEAR COVER................... 75
VALVES AND VALVE SPRINGS............ 76
SPECIFICATIONS
2.5L VM DIESEL........................ 78
TORQUE............................. 80
SPECIAL TOOLS
2.5L VM DIESEL........................ 81
GENERAL INFORMATION
GENERAL SPECIFICATION
Type ........................425CLIEE (36B)
Displacement...................2.5L (2499 cc)
Bore.............................92.00 mm
Stroke............................94.00 mm
Compression Ratio....................20.95:1
Vacuum at Idle..........600mm/Hg (23.6 In/Hg)
Thermostat Opening................80ÉC62ÉC
Generator Rating............Bosch 50/120 Amp
Cooling System Capacity..............9.5Liter
Power Steering Capacity.............0.75 LiterType ........................425CLIEE (36B)
Engine Oil Capacity.....6.5Liters With Oil Filter
Change
Timing System . Pushrod Operated Overhead valves,
With Gear-Driven Camshaft.
Air Intake........................DryFilter
Fuel Feed...........Vacuum Pump Incorporated
in Injection Pump.
Fuel System.............Indirect Fuel Injection
(Precombustion Chamber)
Combustion Cycle....................4Stroke
Cooling System..................Water Cooled
Injection Pump.......Rotary Pump Electronically
Controlled.
9 - 40 ENGINENS/GS
ENGINE DIAGNOSISÐMECHANICAL
CONDITION POSSIBLE CAUSES CORRECTION
LUBRICATING OIL PRESSURE
LOW1. Low oil level. 1a. Check and fill with clean engine
oil.
1b. Check for severe external oil
leaks that could reduce the
pressure.
2. Oil viscosity thin, diluted, or
wrong specification.2. Verify the correct oil is being
used. Check for oil dilution.
3. Improperly operating pressure
switch/gauge3. Verify the pressure switch is
functioning correctly. If not, replace
switch/gauge.
4. Relief valve stuck open. 4. Check/replace valve.
5. Plugged oil filter. 5. Change oil filter. Oil filter change
interval may need to be revised.
6. Oil cooler was replaced, shipping
plugs left in cooler.6. Check/removed shipping plugs.
7. Worn oil pump. 7. Check/replace oil pump.
8. Suction tube loose or seal
leaking.8. Check and replace seal.
9. Worn bearing or wrong bearing
installed.9. Inspect and replace connecting
rod or main bearings. check and
replace piston cooling oil jet.
10. Oil jets under piston loose or
bad fit.10. Check oil jets position.
LUBRICATING OIL LOSS 1. External oil leaks. 1. Visually inspect for oil leaks.
Repair as required.
2. Crankcase being overfilled. 2. Verify that the correct dipstick is
being used.
3. Incorrect oil specification or
viscosity.3a. Make sure the correct oil is
being used.
3b. Look for reduced viscosity from
dilution with fuel.
3c. Review/reduce the oil change
intervals.
4. Oil cooler leak. 4. Check and replace the oil cooler.
5. High blow-by forcing oil out the
breather.5. Check the breather tube area for
signs of oil loss.
9 - 44 ENGINENS/GS
DIAGNOSIS AND TESTING (Continued)
ENGINE DIAGNOSISÐMECHANICAL CONT.
CONDITION POSSIBLE CAUSES CORRECTION
LUBRICATING OIL LOSS
(CONT.)6. Turbocharger leaking oil into the
air intake.6. Inspect air duct for evidence of oil
transfer.
7. Piston rings not sealing (oil being
consumed by the engine).7. Perform blow-by check. Repair as
required.
COMPRESSION KNOCKS 1. Air in fuel system. 1. Bleed the fuel system (refer to
Group 14, Fuel System).
2. Poor quality fuel or water/gasoline
contaminated fuel.2. Verify by operating from a
temporary tank with good fuel. Clean
and flush the fuel supply tank.
Replace fuel/water separator.
3. Engine Overloaded. 3. Verify the engine load rating is not
being exceeded.
4. Improperly operating injectors. 4. Check and replace injectors.
5. Fuel injection system defective. 5a. Instrumented injection. 5b. Timing
solenoid of the fuel pump. 5c. Pre
and post heat time of the glow plugs.
Check the fault codes in the ECU.
EXCESSIVE ENGINE NOISES 1. Drive belt squeal, insufficient
tension or abnormally high loading.1. Inspect the drive belts. Make sure
water pump pulley, generator and
power steering all turn freely.
2. Intake air and exhaust leak. 2. Refer to excessive exhaust smoke.
(Engine Diagnosis and Testing)
3. Excessive valve lash. 3. Make sure the rocker arms are not
bent. Defective hydraulic lash
adjuster.
4. Turbocharger noise. 4. Check turbocharger impeller and
turbine wheel for housing contact.
5. Power function knock. 5. Check and replace rod and main
bearings.
6. Fuel injection system defective. 6a. Instrumented injection. 6b. Timing
solenoid of the fuel pump. 6c. Pre
and post heat time of the glow plugs.
Check the fault codes in the ECU.
NS/GSENGINE 9 - 45
DIAGNOSIS AND TESTING (Continued)