wheel CHRYSLER VOYAGER 1996 Service Manual

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.
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 which will
necessitate replacing the tappet, or by the plunger
partially sticking in the tappet body cylinder. A heavy
click is caused either by a tappet check valve not
seating, or by foreign particles becoming wedged
between the plunger and the tappet body causing 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 inspection and cleaning.
CHECKING ENGINE OIL PRESSURE
Check oil pressure using gauge at oil pressure
switch location. Oil pressure should be 34.47 kPa (5
psi.) at idle or 205 to 551 kPa (30 to 80 psi.) at 3000
RPM.
(1) Remove pressure sending unit and install oil
pressure gauge (Fig. 5).
CAUTION: If oil pressure is 0 at idle, do not run
engine at 3000 RPM.
(2) Warm engine at high idle until thermostat
opens.
SERVICE PROCEDURES
VALVE TIMING
(1) Remove front cylinder head cover and all 6
spark plugs.
(2) Rotate engine until the #2 piston is at TDC of
the compression stroke.
(3) Install a degree wheel on the crankshaft pulley.
(4) With proper adaptor, install a dial indicator
into #2 spark plug hole. Using the indicator find TDC
on the compression stroke.
(5) Position the degree wheel to zero.
(6) Remove dial indicator from spark plug hole.
(7) Place a 5.08 mm (0.200 in.) spacer between the
valve stem tip of #2 intake valve and rocker arm pad.
Allow tappet to bleed down to give a solid tappet
effect.
(8) Install a dial indicator so plunger contacts the
#2 intake valve spring retainer as nearly perpendic-
ular as possible. Zero the indicator.
(9) Rotate the engine clockwise until the intake
valve has lifted .254 mm (0.010 in.).
CAUTION: Do not turn crankshaft any further
clockwise as intake valve might bottom and result
in serious damage.
(10) Degree wheel should read 6 degrees BTDC to
6 degrees ATDC.
MEASURING TIMING CHAIN FOR STRETCH
(1) Place a scale next to timing chain so that any
movement of chain may be measured.
(2) Place a torque wrench and socket on camshaft
sprocket attaching bolt and apply torque in direction
of crankshaft rotation to take up slack; 41 N´m (30 ft.
lb.) with cylinder head installed or 20 N´m (15 ft. lb.)
with cylinder heads removed.With a torque
applied to the camshaft sprocket bolt, crank-
shaft should not be permitted to move. It may
be necessary to block crankshaft to prevent
rotation.
(3) Holding a scale even, with dimension reading
as shown (Fig. 6), along edge of chain links. Apply
torque in the reverse direction to 41 N´m (30 ft. lbs.)
with cylinder heads installed, or 20 N´m (15 ft. lbs.)
with cylinder heads removed. Check amount of chain
movement.
(4) Install a new timing chain, if its movement
exceeds 3.175 mm (1/8 inch).
(5) If chain is not satisfactory, refer to Timing
Chain Removal and Installation in this section.
Fig. 5 Checking Oil Pump Pressure
9 - 96 3.3/3.8L ENGINENS
DIAGNOSIS AND TESTING (Continued)

(4) Remove the vertical and horizontal fasteners
from the engine side bracket. Remove the engine
mount assembly
INSTALLATION
(1) Reverse removal procedure for installation.
Tighten assembly in the following order:
a. Engine mount to rail fasteners to 68 N´m (50 ft.
lbs.).
b. The vertical engine fastener to 102 N´m (75 ft.
lbs.)
c. The horizontal fastener to 150 N´m (111 ft. lbs.).
(2) Install the purge duty solenoid and wiring har-
ness to the engine mount.
(3) Engine mount adjustment, Refer to Engine
Mount Insulator Adjustment of this section.
FRONT MOUNT
REMOVAL
(1) Support the engine and transmission assembly
with a floor jack so it will not rotate.
(2) Remove the front engine mount through bolt
from the insulator and front crossmember mounting
bracket (Fig. 24).
(3) Remove six screws from air dam to allow
access to the front mount screws.
(4) Remove the front engine mount screws and
remove the insulator assembly.
(5) Remove the front mounting bracket, if neces-
sary (Fig. 24).
INSTALLATION
(1) Reverse removal procedure for installation and
tighten fasteners in this order:
a. Tighten bolts 2,3, and 4 to 108 N´m (80 ft. lbs.).
b. Tighten bolts 1 and 5 to 54 N´m (40 ft. lbs.).
(2) Engine mount adjustment, Refer to Engine
Mount Insulator Adjustment of this section.(3) Install six screws to air dam and tighten to 12
N´m (105 in. lbs.).
LEFT SIDE MOUNT
REMOVAL
(1) Raise vehicle on hoist and remove left front
wheel.
(2) Support the transmission with a transmission
jack.
(3) Remove the insulator through bolt from the
mount.
(4) Remove the transmission mount fasteners and
remove mount.
INSTALLATION
(1) Reverse removal procedure for installation.
(2) Tighten mount to transmission bolts to 55 N´m
(40 ft. lbs.)
(3) Tighten through bolt to 75 N´m (55 ft. lbs.)
(Fig. 25).
(4) Engine mount adjustment, Refer to Engine
Mount Insulator Adjustment of this section.
REAR MOUNT
REMOVAL
(1) Raise vehicle on hoist.
(2) Support the transmission with a transmission
jack so it will not rotate.
(3) Remove the insulator through bolt from the
mount and rear suspension crossmember.
(4) Remove the four transmission mount fasteners
and remove the mount.
INSTALLATION
(1) Reverse the removal procedure for installation.
Refer to (Fig. 26). Tighten through bolt to 75 N´m (55
ft. lbs.)
Fig. 23 Engine MountÐRight
Fig. 24 Engine MountingÐFront
NS3.3/3.8L ENGINE 9 - 103
REMOVAL AND INSTALLATION (Continued)

CRANKSHAFT DAMPER
REMOVAL
(1) Disconnect negative cable from battery.
(2) Raise vehicle on hoist.
(3) Remove right wheel and inner splash shield.
(4) Remove drive belt. Refer to Group 7, Cooling
System for procedure.
(5) Remove crankshaft pulley (Fig. 29).
INSTALLATION
(1) Install crankshaft pulley (Fig. 30).
(2) Install drive belt. Refer to Cooling System
Group 7 for installation procedure.
(3) Install inner splash shield and wheel.
(4) Connect negative cable to battery.
ROCKER ARMS AND SHAFT ASSEMBLY
REMOVAL
(1) Remove upper intake manifold assembly. Refer
to Group 11, Intake and Exhaust Manifolds.(2) Disconnect spark plug wires by pulling on the
boot straight out in line with plug.
(3) Disconnect closed ventilation system.
(4) Remove cylinder head cover and gasket.
(5) Remove four rocker shaft bolts and retainers.
(6) Remove rocker arms and shaft assembly.
(7) If rocker arm assemblies are disassembled for
cleaning or replacement. Assemble rocker arms in
their original position. Refer to (Fig. 31) for rocker
arm for positioning on the shaft.
INSTALLATION
(1) Install rocker arm and shaft assemblies with
the stamped steel retainers in the four positions,
tighten to 28 N´m (250 in. lbs.) (Fig. 31).
CAUTION: THE ROCKER ARM SHAFT SHOULD BE
TORQUED DOWN SLOWLY, STARTING WITH THE
CENTER BOLTS. ALLOW 20 MINUTES TAPPET
BLEED DOWN TIME AFTER INSTALLATION OF THE
ROCKER SHAFTS BEFORE ENGINE OPERATION.
(2) Clean cylinder head cover gasket surface.
Inspect cover for distortion and straighten if neces-
sary.
(3) Clean head rail if necessary. Install a new gas-
ket and tighten cylinder head cover fasteners to 12
N´m (105 in. lbs.).
(4) Install closed crankcase ventilation system.
(5) Install spark plug wires.
(6) Install upper intake manifold assembly. Refer
to Group 11, Exhaust Systems and Intake Manifolds.
VALVE STEM SEALS OR SPRINGS, CYLINDER
HEAD NOT REMOVED
(1) Perform fuel system pressure release procedure
before attempting any repairs.
(2) Disconnect negative cable from battery.
(3) Remove air cleaner cover and hose assembly.
Fig. 29 Crankshaft DamperÐRemoval
Fig. 30 Crankshaft DamperÐInstallation
Fig. 31 Rocker Arm Location Left Bank
9 - 106 3.3/3.8L ENGINENS
REMOVAL AND INSTALLATION (Continued)

(6) Start and operate engine. Warm up to normal
operating temperature.
CAUTION: To prevent damage to valve mechanism,
engine must not be run above fast idle until all
hydraulic tappets have filled with oil and have
become quiet.
TIMING CHAIN COVER
REMOVAL
(1) Disconnect negative cable from battery.
(2) Drain cooling system. Refer to Cooling System
Group 7 for procedure.
(3) Support engine and remove right engine
mount.
(4) Raise vehicle on hoist. Drain engine oil.
(5) Remove oil pan and oil pump pick-up. It may
necessary to remove transaxle inspection cover.
(6) Remove right wheel and inner splash shield.
(7) Remove drive belt. Refer to Cooling System
Group 7 for procedure.
(8) Remove A/C compressor and set aside.
(9) Remove A/C compressor mounting bracket.
(10) Remove crankshaft damper (Fig. 44).
(11) Remove idler pulley from engine bracket.
(12) Remove engine bracket (Fig. 45).
(13) Remove cam sensor from chain case cover
(Fig. 46).
(14) Remove chain case cover (Fig. 46).
INSTALLATION
(1) Be sure mating surfaces of chain case cover
and cylinder block are clean and free from burrs.
Crankshaft oil seal must be removed to insure cor-
rect oil pump engagement.
NOTE: DO NOT USE SEALER ON COVER GASKET
(2) Use a new cover gasket, and O-rings (Fig. 47).
Adhere new gasket to chain case cover, making surethat the lower edge of the gasket is flush to 0.5 mm
(0.020 in.) passed the lower edge of the cover. Refer
to Oil Pan sealing outlined in this section.
Fig. 43 Roller Tappets Aligning Yoke and Retainer
Fig. 44 Crankshaft DamperÐRemoval
Fig. 45 Engine Bracket
Fig. 46 Timing Chain Case Cover
NS3.3/3.8L ENGINE 9 - 111
REMOVAL AND INSTALLATION (Continued)

(3) Rotate crankshaft so that the oil pump drive
flats are vertical.
(4) Position oil pump inner rotor so the mating
flats are in the same position as the crankshaft drive
flats (Fig. 47).
(5) Install cover onto crankshaft. Make sure the oil
pump is engaged on the crankshaft correctly or
severe damage may result.
(6) Install chain case cover screws and torque to
27 N´m (20 ft. lbs.).
(7) Install crankshaft oil seal (Fig. 48).
(8) Install crankshaft pulley (Fig. 49).
(9) Install engine bracket (Fig. 45) and torque fas-
teners to 54 N´m (40 ft. lbs.).(10) Install idler pulley on engine bracket.
(11) Install cam sensor. Refer to Group 8D, Igni-
tion System for installation procedure.
(12) Install A/C compressor mounting bracket.
(13) Install A/C compressor.
(14) Install drive belt Refer to Group 7, Cooling
System for installation procedure.
(15) Install inner splash shield and wheel.
(16) Install oil pump pick-up and oil pan and tran-
saxle inspection cover if removed.
(17) Install engine mount.
(18) Fill crankcase with oil to proper level.
(19) Fill cooling system. Refer to Group 7, Cooling
System for procedure.
(20) Connect negative cable to battery.
TIMING CHAIN
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove timing chain cover. Refer to procedure
outlined in this section.
(3) Remove camshaft sprocket attaching bolt, and
timing chain with camshaft sprocket.
(4) Using a suitable puller remove the crankshaft
sprocket. Be careful not to damage the crankshaft
surface.
INSTALLATION
(1) Position a new crankshaft sprocket on the
shaft, install sprocket with suitable tool and mallet.
Be sure sprocket is seated into position.
(2) Rotate crankshaft so the timing arrow is to the
12 o'clock position.
(3) Place timing chain around camshaft sprocket
and place the timing mark to the 6 o'clock position.
(4) Align the dark colored links with the dot on the
camshaft sprocket, place timing chain around crank-
shaft sprocket with the dark colored link lined up
Fig. 47 Timing Chain Case Cover Gaskets and
O-Rings
Fig. 48 Crankshaft Oil SealÐInstallation
Fig. 49 Crankshaft DamperÐInstallation
9 - 112 3.3/3.8L ENGINENS
REMOVAL AND INSTALLATION (Continued)

(3) Slowly rotate crankshaft clockwise, forcing out
upper half of bearing shell.
INSTALLATION
NOTE: Only one main bearing should be selec-
tively fitted while all other main bearing caps are
properly tightened.
When installing a new upper bearing shell, slightly
chamfer the sharp edges from the plain side.
(1) Start bearing in place, and insert Main Bearing
Tool C-3059 into oil hole of crankshaft (Fig. 64).
(2) Slowly rotate crankshaft counterclockwise slid-
ing the bearing into position. Remove Special Main
Bearing Tool C-3059.
(3) Install each main cap and tighten bolts finger
tight.
(4) Tighten number 1, 3 and 4 main cap bolts to 41
N´m + 1/4 Turn (30 ft. lbs.+ 1/4 Turn).(5) Rotate the crankshaft until number 6 piston is
at TDC.
(6) To ensure correct thrust bearing alignment the
following procedure must be done:
a. Move crankshaft all the way to the rear of its
travel.
b. Then, move crankshaft all the way to the front
of its travel.
c. Wedge a appropriate tool between the rear of
the cylinder block and rear crankshaft counter-
weight. This will hold the crankshaft in it's most for-
ward position.
d. Tighten the #2 Thrust Bearing cap bolts to 41
N´m + 1/4 Turn (30 ft. lbs.+ 1/4 Turn). Remove the
holding tool.
(7) Install oil pan.
(8) Fill engine crankcase with proper oil to correct
level.
CRANKSHAFT OIL SEALÐFRONT
REMOVAL
(1) Disconnect negative cable from battery.
(2) Raise vehicle on hoist. Remove right wheel and
inner splash shield.
(3) Remove drive belt. Refer to Group 7, Cooling
System for procedure.
(4) Remove crankshaft damper (Fig. 65).
(5) Using Tool 6341A to remove oil seal (Fig. 66).
Be careful not to damage that crankshaft seal sur-
face of cover.
INSTALLATION
(1) Install new seal by using Tool C-4992 (Fig. 67).
(2) Place seal into opening with seal spring
towards the inside of engine. Install seal until flush
with cover.
(3) Install crankshaft pulley using plate L-4524.
Thrust Bearing/washer and 5.9 inch screw (Fig. 68).
Fig. 63 Main Bearing Identification
Fig. 64 Removing and Installing Upper Main Bearing
With Special Tool C-3059
Fig. 65 Crankshaft DamperÐRemoval
NS3.3/3.8L ENGINE 9 - 117
REMOVAL AND INSTALLATION (Continued)

(4) Install drive belt Refer to Group 7, Cooling
System for installation procedure.
(5) Install inner splash shield and wheel.
(6) Lower vehicle and connect negative cable to
battery.
CRANKSHAFT OIL SEALÐREAR
REMOVAL
(1) Insert a 3/16 flat bladed pry tool between the
dust lip and the metal case of the crankshaft seal.
Angle the pry tool (Fig. 69) through the dust lip
against metal case of the seal. Pry out seal.
CAUTION: Do not permit the pry tool blade to con-
tact crankshaft seal surface. Contact of the pry toolblade against crankshaft edge (chamfer) is permit-
ted.
INSTALLATION
CAUTION: If burr or scratch is present on the
crankshaft edge (chamfer), cleanup with 400 grit
sand paper to prevent seal damage during installa-
tion of new seal.
(1) Place Special Tool 6926-1 magnetic pilot tool on
crankshaft (Fig. 70).
(2) Lightly coat seal O.D. with MopartStud N'
Bearing Mount Adhesive or equivalent.
(3) Place seal over Special Tool 6926-1 Pilot. Using
Special Tool 6926-2 Installer with C-4171 Handle,
drive seal into the retainer housing (Fig. 70).
REAR CRANKSHAFT SEAL RETAINER
When retainer removal is required, remove
retainer and clean engine block and retainer of old
gasket. Make sure surfaces are clean and free of oil.
Fig. 66 Front Crankshaft Oil SealÐRemoval
Fig. 67 Crankshaft Oil SealÐInstallation
Fig. 68 Crankshaft DamperÐInstallation
Fig. 69 Rear Crankshaft Oil SealÐRemoval
9 - 118 3.3/3.8L ENGINENS
REMOVAL AND INSTALLATION (Continued)

SPLASH LUBRICATION
Oil returning to the pan from pressurized compo-
nents supplies lubrication to the valve stems. Cylin-
der bores and wrist pins are splash lubricated from
directed slots on the connecting rod thrust collars.
ENGINE COMPONENTS
CYLINDER BLOCK AND BEDPLATE ASSEM-
B LY:A partial open deck is used for cooling and
weight reduction with water pump molded into the
block. Nominal wall thickness is 4 mm. The bedplate
incorporates main bearing caps. Rear seal retainer is
integral with the block.
CRANKSHAFT:A nodular cast iron crankshaft is
used. The engine has 5 main bearings, with number
3 flanged to control thrust. The 52 mm diameter
main and 48 mm diameter crank pin journals (all)
have undercut fillet radiuses that are deep rolled for
added strength. To optimize bearing loading 8 coun-
terweights are used. Hydrodynamic seals provide end
sealing, where the crankshaft exits the block.
Anaerobic gasket material is used for parting line
sealing. A sintered iron timing belt sprocket is
mounted on the crankshaft nose. This sprocket trans-
mits crankshaft movement, via timing belt to the
camshaft sprocket providing timed valve actuation.
PISTONS:The SOHC EngineDOES NOThave
provision for a free wheeling valve train. Non free
wheeling valve train means, in the event of a broken
timing belt Pistons will contact the Valves. All
engines use pressed-in piston pins to attach forged
powdered metal connecting rods. The connecting rods
are a cracked cap design and are not repairable. Hexhead cap screw are used to provide alignment and
durability in the assembly. Pistons And Connecting
rods are serviced as an assembly.
PISTON RINGS:The piston rings include a
molybdenum faced top ring for reliable compression
sealing and a taper faced intermediate ring for addi-
tional cylinder pressure control. Oil Control Ring
Package consist of 2 steel rails and a expander
spacer.
CYLINDER HEADÐSOHC:It features a Single
Over Head Camshaft, four-valves per cylinder cross
flow design. The valves are arranged in two inline
banks, with the two intake per cylinder facing
toward the radiator. The exhaust valves facing
toward the dash panel. Rocker arm shafts mount
directly to the cylinder head. It incorporates powder
metal valve guides and seats. The hollow rocker arm
shafts supplies oil to the hydraulic lash adjusters,
camshaft and valve mechanisms.
CAMSHAFTÐSOHC:The nodular iron camshaft
has five bearing journals and 3 cam lobes per cylin-
der. Provision for cam position sensor on the cam at
the rear of cylinder head which also acts as thrust
plate. A hydrodynamic oil seal is used for oil control
at the front of the camshaft.
VALVESÐSOHC:Four valves per cylinder are
actuated by roller rocker arms/hydraulic lash adjust-
ers assemblies which pivot on rocker arm shafts. All
valves have 6 mm diameter chrome plated valve
stems. The valve train has 33 mm (1.299 inch) diam-
eter intake valves and 28 mm (1.10 inch) diameter
exhaust valves. Viton rubber valve stem seals are
integral with spring seats. Valve springs, spring
retainers, and locks are conventional design.
INTAKE MANIFOLD:The intake manifold is a
molded plastic composition, attached to the cylinder
head with ten fasteners. This long branch design
enhances low and mid-range torque.
EXHAUST MANIFOLD:The exhaust manifold is
made of nodular cast iron for strength and high tem-
peratures. Exhaust gasses exit through a machined,
articulated joint connection to the exhaust pipe.
DIAGNOSIS AND TESTING
CHECKING ENGINE OIL PRESSURE
(1) Remove oil pressure switch and install gauge
assembly C-3292 with adaptor.
(2) Run engine until thermostat opens.
CAUTION: If oil pressure is 0 at idle, Do Not per-
form the 3000 RPM test in the next step.
(3) Oil Pressure:Curb Idle25 kPa (4 psi) mini-
mum3000 RPM170-550 kPa (25-80 psi).
Fig. 2 Engine Lubrication SystemÐ SOHC
NS/GSENGINE 9 - 3
DESCRIPTION AND OPERATION (Continued)

DIAGNOSIS AND TESTING
ENGINE DIAGNOSISÐPERFORMANCE
CONDITION POSSIBLE CAUSES CORRECTION
ENGINE WILL NOT
CRANK OR CRANKS
SLOWLY1. Starting motor operating, but not cranking the
engine.1. Remove the starter motor. Check for broken
flywheel teeth or a broken starter motor spring.
2. Crankshaft rotation restricted. 2. Rotate the engine to check for rotational
resistance.
3. Starting circuit connections loose or corroded. 3. Clean and tighten connections.
4. Neutral safety or starter relay inoperative. 4. Check starter relay supply voltage and proper
operation of neutral safety switch (if equipped).
Replace defective parts.
5. Battery charge low. 5. Check Battery voltage. Replace battery if a
charge cannot be held.
6. No voltage to starter solenoid. 6. Check voltage to solenoid. If necessary, replace
the solenoid.
7. Solenoid or starter motor inoperative. 7. Replace starter motor.
ENGINE CRANKS, BUT
WILL NOT START, NO
SMOKE1. No fuel in supply tank. 1. Fill fuel supply.
2. Electrical fuel shutdown solenoid not operating. 2. Check for loose wires and verify that the fuel
shutdown solenoid is functioning. Check for fault
codes in the ECU.
3. Fuel injection system defective: Cranking speed
sensor. Loose connection between ECU and
harness. No power supply to the ECU. Loose
connection between injection pump and harness.3. Check for fault codes at ECU. Refer to Group 14,
Fuel System for repairs procedures.
4. Air intake or exhaust plugged. 4. Remove the obstruction.
5. Fuel filter plugged. 5. Drain fuel/water separator and replace fuel filter.
6. Excessive fuel inlet restriction. 6. Check for restriction. Correct cause.
7. Injection pump not getting fuel or fuel is aerated. 7. Check fuel flow/bleed fuel system.
8. One or more injectors worn or not operating
properly.8. Check/replace bad or improperly operating
injectors.
9. Camshaft out of time. 9. Check/correct timing chain sprocket alignment.
ENGINE HARD TO
START, OR WILL NOT
START, SMOKE FROM
EXHAUST1. Incorrect starting procedure. 1. The fuel shutoff solenoid control must be in the
run position. Ensure the proper procedure is being
used.
2. Cranking speed to slow. 2. Check the battery, starter motor and look for
loose or corroded wiring connections.
3. Cylinder head heater plugs defective. 3. Verify system is working. Verify connection
between heater plug relay and ECU. Repair/replace
inoperative parts.
4. Insufficient intake air 4. Inspect or replace air filter and check for
obstruction in air supply.
5. Air in fuel system or the fuel supply is
inadequate.5. Check the fuel flow through the filter and bleed
system. Locate and eliminate the air source.
6. Contaminated fuel. 6. Verify by operating the engine with clean fuel
from a temporary tank. Check for the presence of
gasoline. Drain and flush fuel supply tank. Replace
fuel/water separator filter.
7. Fuel screen plugged. 7. Check fuel screen.
8. One or more injectors worn or not operating
properly.8. Check/replace improperly operating injectors.
9. Injector pump out of time. 9. Check pump timing. Refer to Group 14, Fuel
System for procedure.
10. Engine compression low. 10. Check compression to identify the problem.
11. Fuel injection system defective. 11. Vacuum modulator defective causing EGR to
open in cold condition. Check for fault codes in the
ECU.
NS/GSENGINE 9 - 43

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)