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
Type ........................425CLIEE (36B)
Lubrication . Pressure Lubrication by Rotary Pump,
Full-Flow Filtration
Engine Rotation....Clockwise Viewed From Front
Cover
ENGINE IDENTIFICATION
The engine model code (3-digit number/letter code)
and serial number are stamped on the forward facing
side of the engine block (Fig. 1).
DESCRIPTION AND OPERATION
LUBRICATION SYSTEM
The pressurized system (Fig. 2) uses a rotary pump
(3) located in the front of the engine block, driven by
a gear which meshes directly with the crankshaft
gear. All the oil sent to every lubricated part is fil-
tered. The pump sends the oil through a pressure
relief valve (2) to the filter (7) and through galleries
in the crankcase to the crankshaft bearings (8), cam-
shaft bearings (11) and turbocharger (10). The piston
pins, connecting rod small ends and insides of the
pistons are lubricated and cooled by oil sprayed out
from jets (9) in the crankshaft mounting blocks. The
lubricating oil is sent to the rockers (12) through anexternal pipe (Fig. 3). A valve in the filter cartridge
enables the oil to be circulated even when the car-
tridge is clogged.
Sump inlet (1). Pressure relief valve (2). Oil pump
(3). Oil cooler (6). Filter cartridge (7). Crankshaft
bearings (8). Jet valve (9). Turbocharger bearings
(10). Camshaft bearings (11). Rockers (12).
Fig. 2 Lubrication System
Fig. 1 Engine Code Location
NS/GSENGINE 9 - 41
GENERAL INFORMATION (Continued)
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)
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 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)
(28) Remove radiator support bolts.It is neces-
sary to loosen the receiver/dryer to gain access
to the radiator bolts.
(29) Remove radiator and fans as an assembly.
(30) Remove accessory drive belt generator/power
steering. Refer to Group 7, for procedure.
(31) Remove both power steering lines at pump,
and cap both lines.
NOTE: It is not necessary to discharge A/C system
for engine removal.
(32) Remove A/C compressor. Secure compressor
away from engine for clearance during engine
removal.
(33) Remove Generator and adjusting bracket.
NOTE: Do not remove the mounting base from the
generator. It is aligned at the factory and cannot be
realigned in the field.
(34) Hoist vehicle.
(35) Remove exhaust pipe at turbo outlet.
(36) Remove connections at starter.
(37) Remove power steering high pressure line
bracket at rear of oil pan.
(38) Remove both driveshafts from transaxle. Refer
to Group 2, Suspension and Driveshafts.
(39) Disconnect clutch cable at transaxle.
(40) Remove reinforcement plate on lower cross-
member.
(41) Remove front and rear engine mounts. Refer
to procedure outlined in this section.
(42) Drain engine oil and remove oil filter if neces-
sary.
(43) Mount both special tool, engine support brack-
ets VM-1026 to cylinder block (Fig. 21).
(44) Using engine dolly and cradle assembly with
4 adjustable posts align posts with holes in the
engine support brackets.
(45) Lower vehicle so weight ofonly the engine
and transmissionis on the dolly and cradle assem-
bly.
(46) Remove left side splash shield to gain access
to thru bolt for left side mount.
(47) Remove right engine mount and left side
mount. Refer to procedure outlined in this section.
(48) Raise vehicle slowly. It may be necessary to
move the engine/transmission assembly on the dolly
to allow for removal around body.
(49) Reverse removal procedure for installation.
CYLINDER HEAD COVER
REMOVAL
(1) Disconnect the battery cables.
(2) Remove generator bracket.(3) Remove breather hose.
(4) Remove coolant pressure tank.
(5) Remove cylinder head cover.
INSTALLATION
(1) Install cylinder head cover, torque nuts to 23.5
N´m (208 in. lbs.).
(2) Install coolant pressure tank.
(3) Install breather hose.
(4) Install generator bracket, tighten bolts to 7
N´m (4 ft. lbs.).
(5) Connect battery cable.
ROCKER ARMS AND PUSH RODS
REMOVAL
(1) Disconnect the battery cables.
(2) Remove generator bracket.
(3) Remove breather hose.
(4) Remove coolant pressure tank.
(5) Remove cylinder head cover.
(6) Remove rocker retaining nuts (Fig. 22).
(7) Remove rocker assembly. Place them on a
bench in the same order as removed.
(8) Remove the push rods and place them on a
bench in the same order as removed.
INSTALLATION
(1) Install the push rods in the same order as
removed.
(2) Install rocker arm assemblies in the same
order as removed. Tighten the rocker arm nuts to
29.4 N´m (264 in. lbs.) torque.
Fig. 21 Engine Removal
9 - 54 ENGINENS/GS
REMOVAL AND INSTALLATION (Continued)
(10) Disconnect EGR tube from EGR valve (Fig.
25).
(11) Remove exhaust pipe from turbocharger elbow
and.
(12) Disconnect oil feed line from turbo (Fig. 24).
(13) Disconnect oil drain line from turbo.
(14) Remove Intake manifold. Refer to Group 11,
Exhaust System and Intake Manifold.
(15) Remove lift eye and brake vacuum tube at
rear of exhaust manifold.(16) Remove the support strut from block to turbo-
charger exhaust elbow.
(17) Remove Exhaust manifold. Refer to Group 11,
Exhaust System and Intake Manifold.
(18) Remove oil line at pressure switch.
(19) Remove oil feed line for rocker arm assemblies
(Fig. 26).
(20) Remove Crankcase breather hose from valve
cover
(21) Remove the engine cylinder head cover.
Fig. 23 Intercooler Assembly
Fig. 24 Turbocharger
Fig. 25 EGR Valve and Tube
Fig. 26 Rocker Arm Oil Feed Lines
9 - 56 ENGINENS/GS
REMOVAL AND INSTALLATION (Continued)
70É using angle torque tool. Then rotate the bolts an
additional 70É following tightening sequence.
(10) Then, tighten the 14mm bolts with special
tool VM-1018 in the following manner:
(11) Side bolts (M1-M2): Tighten M1 bolts to 30
N´m, then rotate them 85É (65). Tighten M2 bolts to
30 N´m, then rotate them 85É (65).
(12)2nd Phase:After 20 minutes of engine oper-
ation at operating temperature, allow engine to cool
down completely. Then retorque the head bolts as fol-
lows:
(13) Central bolts A-L: Starting from bolt A,
slacken and retorque it immediately to 30 N´m + 65É.
Rotate the bolt an additional 65É. Then proceed in
the same way, bolt by bolt, following alphabetical
order, as indicated.
(14) Side bolts M1-M2:Without slackening,
torque bolts M1 then bolts M2 to 90 N´m (66 ft. lbs.).
(15) Tighten intake nuts to 30 N´m (22 ft. lbs.) and
exhaust manifolds nuts to 30 N´m (22 ft. lbs.) speci-
fied torque after completing Phase 2.
(16) If the engine cylinder head is to be replaced
and the original valves used, measure the valve stem
diameter. Only standard size valves can be used with
a service replacement engine cylinder head unless
the replacement head valve stem guide bores are
reamed to accommodate oversize valve stems.
Remove all carbon buildup and reface the valves.
(17) Tighten oil feed lines for rocker arm assem-
blies and oil pressure switch to 13 N´m (112 in. lbs.).
(18) Install push rods and rocker arm assemblies,
tighten nut to 29.4 N´m (264 in. lbs.).(19) Install fuel injectors use tool VM-1012 (refer
to Group 14, Fuel System).
(20) Install valve cover, tighten nuts to 14.7 N´m
(132 in. lbs.).
(21) Connect crankcase breather hose.
(22) Connect the injector sensor wire connector,
and the glow plug connectors.
(23) Install oil feed line, tighten banjo bolts to 12.7
N´m (108 in. lbs), and oil drain line to turbo.
(24) Install water manifold tighten bolts to 12 N´m
(106 in. lbs.).
(25) Install exhaust pipe to turbo elbow, tighten
bolts to 28 N´m (250 in. lbs.).
(26) Install the support strut from block to turbo-
charger exhaust elbow.
(27) Install EGR tube to EGR valve, tighten bolts
to 26 N´m (19 ft. lbs.).
(28) Install intercooler hoses at intake manifold.
(29) Install coolant pressure bottle and hoses.
(30) Install wiper module. Refer to Group 8K,
Windshield Wiper Unit Installation for procedure.
(31) Install intercooler hose at turbocharger tube.
(32) Install fuel injector lines from the pump to
injectors, tighten nuts to 17.6 N´m (156. lbs.).
(33) Connect the upper radiator hose.
(34) Connect negative cable to battery.
(35) Fill the cooling system. Check for leaks.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN DIRECT
LINE WITH THE FAN. DO NOT PUT HANDS NEAR
THE PULLEYS, BELTS OR FAN. DO NOT WEAR
LOOSE CLOTHING.
Fig. 33 Engine Cylinder Head Bolt Tightening Sequence
NS/GSENGINE 9 - 59
REMOVAL AND INSTALLATION (Continued)