1999 DODGE DURANGO engine coolant

Downloaded from www.Manualslib.com manuals search engine (14) Install the crankshaft damper. Tighten
damper bolt 175 N´m (130 Ft. Lbs.).
(15) Install the power steering pump.
(16) Install the fan blade assembly and fan
shroud.
(17) Install the cylinder head cover.
(18) Install the intake manifold.
(19) Refill the cooling system
(20) Raise the vehicle.
(21) Install the exhaust pipe onto the left exhaust
manifold.
(22) Lower the vehicle.
(23) Connect the negative cable to the battery.
(24) Start the engine and check for leaks.
CYLINDER HEADÐRIGHT
REMOVAL
(1) Disconnect battery negitive cable.
(2) Raise the vehicle on a hoist.
(3) Disconnect the exhaust pipe at the right side
exhaust manifold.
(4) Drain the engine coolant. Refer to COOLING
SYSTEM.
(5) Lower the vehicle.
(6) Remove the intake manifold. Refer to proce-
dure in this section.
(7) Remove the cylinder head cover. Refer to proce-
dure in this section.
(8) Remove the fan shroud. Refer to COOLING
SYSTEM.
(9) Remove oil fill housing from cylinder head.
(10) Remove accessory drive belt. Refer to COOL-
ING SYSTEM.
(11) Rotate the crankshaft until the damper timing
mark is aligned with TDC indicator mark (Fig. 57).
(12) Verify the V8 mark on the camshaft sprocket
is at the 12 o'clock position (Fig. 59). Rotate the
crankshaft one turn if necessary.
(13) Remove the crankshaft damper. Refer to
Crankshaft Damper in this section.(14) Remove the timing chain cover. Refer to Tim-
ing Chain Cover in this section.
(15) Lock the secondary timing chains to the idler
sprocket using Special Tool 8515 (Fig. 58).
NOTE: Mark the secondary timing chain prior to
removal to aid in installation.
(16) Mark the secondary timing chain, one link on
each side of the V8 mark on the camshaft drive gear
(Fig. 59).
(17) Remove the right side secondary chain ten-
sioner. Refer to Timing Chain and Sprockets in this
section.
(18) Remove the cylinder head access plug (Fig.
64).
(19) Remove the right side secondary chain guide.
Refer to Timing Chain and Sprockets in this section.
(20) Remove the retaining bolt and the camshaft
drive gear.
CAUTION: Do not allow the engine to rotate. severe
damage to the valve train can occur.
CAUTION: Do not overlook the four smaller bolts at
the front of the cylinder head. Do not attempt to
remove the cylinder head without removing these
four bolts.
CAUTION: Do not hold or pry on the camshaft tar-
get wheel for any reason. A damaged target wheel
can result in a vehicle no start condition.
Fig. 63 Cylinder Head Tightening Sequence
Fig. 64 Cylinder Head Access Plugs
1 ± RIGHT CYLINDER HEAD ACCESS PLUG
2 ± LEFT CYLINDER HEAD ACCESS PLUG
9 - 44 4.7L ENGINEDN
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine (24) Coat the large threaded access plug with
MopartThread Sealant with Teflon, then install
into the right cylinder head and tighten to 81 N´m
(60 ft. lbs.) (Fig. 77).(25) Install the oil fill housing.
(26) Install access plug in left cylinder head (Fig.
77).
(27) Install power steering pump. Refer to Group
19, Steering for procedure.
(28) Install radiator fan shroud. Refer to Group 7,
Cooling System for procedure.
(29) Fill cooling system. Refer to Group 7, Cooling
System for coolant fill procedure.
(30) Connect negative cable to battery.
IDLER SHAFTÐTIMING DRIVE
REMOVAL
(1) Remove the timing chain and sprockets. Refer
to procedure in this section.
NOTE: To remove the idler shaft, it is necessary to
tap threads into the shaft to install the removal tool.
(2) Using a 12 mm X 1.75 tap, cut threads in the
idler shaft center bore (Fig. 89).
(3) Cover the radiator core with a suitable cover.
CAUTION: Use care when removing idler shaft, DO
NOT strike the radiator cooling fins with the slide
hammer.
(4) Using Special Tool 8517 Slide Hammer, remove
the idler shaft (Fig. 90).
Fig. 87 Tightening Right Side Camshaft Sprocket
Bolt
1 ± TORQUE WRENCH
2 ± SPECIAL TOOL 6958 WITH ADAPTER PINS 8346
3 ± LEFT CAMSHAFT SPROCKET
4 ± RIGHT CAMSHAFT SPROCKET
Fig. 88 Measuring Idler Gear End Play
1 ± IDLER SPROCKET ASSEMBLY
2 ± DIAL INDICATOR
Fig. 89 Tapping Idler Shaft For Special Tool 8517
1 ± IDLER SHAFT
2 ± TAP 12mm X 1.75
DN4.7L ENGINE 9 - 55
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine (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.
(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. 17). The special
sleeve places the valve at the correct height for
checking with a dial indicator.
Fig. 17 Positioning Valve with Tool C-3973
1 ± VALVE
2 ± SPACER TOOL
DN5.2L ENGINE 9 - 95
SERVICE PROCEDURES (Continued)

Downloaded from www.Manualslib.com manuals search engine (9) Disconnect the accelerator linkage.
(10) Remove throttle body.
(11) Perform the Fuel System Pressure release
procedure (refer to Group 14, fuel System).
(12) Disconnect the fuel supply line.
(13) Disconnect the starter wires.
(14) Disconnect the oil pressure sending unit wire.
(15) Discharge the air conditioning system, if
equipped (refer to Group 24, Heating and Air Condi-
tioning for service procedures).
(16) Disconnect the air conditioning hoses.
(17) Disconnect the power steering hoses, if
equipped.
(18) Remove starter motor (refer to Group 8B, Bat-
tery/Starter/Generator Service).
(19) Remove the generator (refer to Group 8B, Bat-
tery/Starter/Generator Service).
(20) Raise and support the vehicle on a hoist.
(21) Disconnect exhaust pipe at manifold.
(22) Refer to Group 21, Transmissions for trans-
mission removal.
CAUTION: DO NOT lift the engine by the intake
manifold.
(23) Install an engine lifting fixture.
(24) The engine and front driving axle (engine/ax-
le/transmission) are connected through insulators
and support brackets. Separate the engine as follows:
²LEFT SIDEÐRemove 2 bolts attaching
(engine/pinion nose/transmission) bracket to trans-
mission bell housing. Remove 2 bracket to pinion
nose adaptor bolts. Separate engine from insulator by
removing upper nut washer assembly and bolt from
engine support bracket.
²RIGHT SIDEÐRemove 2 bracket to axle (dis-
connect housing) bolts and a bracket to bell housing
bolt. Separate engine from insulator by removing
upper nut washer assembly and bolt from engine
support bracket.
(25) Lower the vehicle.
(26) Install engine assembly on engine repair
stand.
INSTALLATION
(1) Remove engine from the repair stand and posi-
tion in the engine compartment.
(2) Install an engine support fixture.
(3) Raise and support the vehicle on a hoist.
(4) Install the engine front mounts.
(5) Refer to Group, 21 Transmissions for transmis-
sion installation
(6) Install the inspection plate.
(7) Remove transmission support.
(8) Install exhaust pipe to manifold.
(9) Lower the vehicle.
(10) Remove engine lifting fixture.(11) Install the generator (refer to Group 8B, Bat-
tery/Starter/Generator Service).
(12) Install starter motor (refer to Group 8B, Bat-
tery/Starter/Generator Service).
(13) Connect power steering hoses, if equipped.
(14) Connect air conditioning hoses.
(15) Evacuate and charge the air conditioning sys-
tem, if equipped (refer to Group 24, Heater and Air
Conditioning for service procedures).
(16) Using a new gasket, install throttle body.
Tighten the throttle body bolts to 23 N´m (200 in.
lbs.) torque.
(17) Connect the accelerator linkage.
(18) Connect the starter wires.
(19) Connect the oil pressure sending unit wire.
(20) Install the distributor cap and wiring.
(21) Connect the vacuum supply lines to the
intake manifold.
(22) Connect the fuel supply lines.
(23) Install the radiator (refer to Group 7, Cooling
System). Connect the radiator hoses and heater
hoses.
(24) Install fan shroud in position.
(25) Fill cooling system (refer to Group 7, Cooling
System for the proper procedure).
(26) Install the air cleaner.
(27) Install the battery.
(28) Warm engine and adjust.
(29) Install hood and line up with the scribe
marks.
(30) Road test vehicle.
INTAKE MANIFOLD
REMOVAL
(1) Disconnect the battery negative cable.
(2) Drain the cooling system. Refer to COOLING
SYSTEM.
(3) Remove the A/C compressor. Refer to HEAT-
ING and AIR CONDITIONING.
(4) Remove the generator. Refer to CHARGING
SYSTEM.
(5) Remove the accessory drive bracket.
(6) Remove the air cleaner assembly and air inlet
hose.
(7) Perform the fuel pressure release procedure.
Refer to FUEL SYSTEM.
(8) Disconnect the fuel supply line from the fuel
rail. Refer to FUEL SYSTEM.
(9) Disconnect the accelerator linkage and, if so
equipped, the speed control and transmission kick-
down cables.
(10) Remove the distributor cap and wires.
(11) Disconnect the coil wires.
(12) Disconnect the coolant temperature sending
unit wire.
DN5.2L ENGINE 9 - 103
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine place, inspect to make sure seals are in place.
Remove alignment studs if used.
(9) The following torque sequence duplicates the
expected results of the automated assembly system
(Fig. 39).²Step 1ÐTighten bolts 1 thru 4, in sequence, to 8
N´m (72 in. lbs.) torque. Tighten in alternating steps
1.4 N´m (12 in. lbs.) torque at a time.
²Step 2ÐTighten bolts 5 thru 12, in sequence, to
8 N´m (72 in. lbs.) torque.
²Step 3ÐCheck that all bolts are tightened to 8
N´m (72 in. lbs.) torque.
²Step 4ÐTighten all bolts, in sequence, to 16 N´m
(12 ft. lbs.) torque.
²Step 5ÐCheck that all bolts are tightened to 16
N´m (12 ft. lbs.) torque.
(10) Install closed crankcase ventilation and evap-
oration control systems.
(11) Install the coil wires.
(12) Connect the coolant temperature sending unit
wire.
(13) Connect the heater hoses and bypass hose.
(14) Install distributor cap and wires.
(15) Connect the accelerator linkage and, if so
equipped, the speed control and transmission kick-
down cables.
(16) Install the fuel supply line to the fuel rail.
(17) Install the accessory drive bracket and A/C
compressor.
(18) Install the generator and accessory drive belt.
Tighten generator mounting bolt to 41 N´m (30 ft.
lbs.) torque.
(19) Install the air cleaner assembly and air inlet
hose.
(20) Fill cooling system.
(21) Connect the battery negative cable.
EXHAUST MANIFOLD
REMOVAL
(1) Disconnect the battery negative cable.
(2) Raise the vehicle.
(3) Remove the exhaust pipe to manifold nuts.
(4) Lower the vehicle.
(5) Remove three nuts, heat shield and washers
from the right side exhaust manifold, if necessary
(Fig. 40).
(6) Remove two nuts, heat shield and washers
from the left side exhaust manifold, if necessary (Fig.
41).
(7) Remove bolts, nuts and washers attaching
manifold to cylinder head.
(8) Remove manifold from the cylinder head.
INSTALLATION
CAUTION: If the studs came out with the nuts when
removing the exhaust manifold, install new studs.
(1) Position the exhaust manifolds on the two
studs located on the cylinder head. Install conical
washers and nuts on these studs (Fig. 42).
Fig. 38 Intake Manifold Flange Gasket Alignment
1 ± FLANGE GASKET
2 ± ALIGNMENT TABS
3 ± CYLINDER HEAD GASKET
Fig. 39 Intake Manifold Bolt Tightening SequenceÐ
5.9L Engine
DN5.2L ENGINE 9 - 105
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine (6) To align the bearing cap, use cap slot, align-
ment dowel and cap bolts. DO NOT remove excess
material after assembly. DO NOT strike rear cap
more than 2 times for proper engagement.
(7) Install the rear main bearing cap with cleaned
and oiled cap bolts. Alternately tighten ALL cap bolts
to 115 N´m (85 ft. lbs.) torque.
(8) Install oil pump.
(9) Apply MopartSilicone Rubber Adhesive Seal-
ant, or equivalent, at bearing cap to block joint to
provide cap to block and oil pan sealing (Fig. 72).
Apply enough sealant until a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(10) Immediately install the oil pan.
LOWER SEAL
REMOVAL
(1) Remove the oil pan.
(2) Remove the oil pump from the rear main bear-
ing cap.
(3) Remove the rear main bearing cap and discard
the old lower seal.
INSTALLATION
(1) Clean the rear main cap mating surfaces
including the oil pan gasket groove.
(2) Carefully install a new upper seal (refer to
Upper Seal Replacement - Crankshaft Installed pro-
cedure above).
(3) Lightly oil the new lower seal lips with engine
oil.
(4) Install a new lower seal in bearing cap with
the white paint facing the rear of engine.
(5) Apply 5 mm (0.20 in) drop of MopartGasket
Maker, or equivalent, on each side of the rear main
bearing cap (Fig. 71). DO NOT over apply sealant or
allow the sealant to contact the rubber seal. Assem-
ble bearing cap to cylinder block immediately after
sealant application.
(6) To align the bearing cap, use cap slot, align-
ment dowel and cap bolts. DO NOT remove excess
material after assembly. DO NOT strike rear cap
more than 2 times for proper engagement.
(7) Install the rear main bearing cap with cleaned
and oiled cap bolts. Alternately tighten the cap bolts
to 115 N´m (85 ft. lbs.) torque.
(8) Install oil pump.
(9) Apply MopartSilicone Rubber Adhesive Seal-
ant, or equivalent, at bearing cap to block joint to
provide cap to block and oil pan sealing (Fig. 72).
Apply enough sealant until a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(10) Immediately install the oil pan.
ENGINE CORE OIL AND CAMSHAFT PLUGS
Engine core plugs have been pressed into the oil
galleries behind the camshaft thrust plate (Fig. 73).
This will reduce internal leakage and help maintain
higher oil pressure at idle.
REMOVAL
(1) Using a blunt tool such as a drift or a screw-
driver and a hammer, strike the bottom edge of the
cup plug (Fig. 74).
(2) With the cup plug rotated, grasp firmly with
pliers or other suitable tool and remove plug (Fig.
74).
INSTALLATION
Thoroughly clean inside of cup plug hole in cylin-
der block or head. Be sure to remove old sealer.
Be certain the new plug is cleaned of all oil or
grease.
(1) Coat edges of plug and core hole with Mopart
Gasket Maker, or equivalent.
CAUTION: DO NOT drive cup plug into the casting,
as restricted coolant flow can result and cause seri-
ous engine problems.
(2) Using proper plug drive, drive cup plug into
hole. The sharp edge of the plug should be at least
0.50 mm (0.020 in.) inside the lead-in chamfer.
(3) It is not necessary to wait for curing of the
sealant. The cooling system can be filled and the
vehicle placed in service immediately.
Fig. 73 Location of Cup Plugs in Oil Galleries
1 ± CUP PLUGS
9 - 120 5.2L ENGINEDN
REMOVAL AND INSTALLATION (Continued)

Downloaded from www.Manualslib.com manuals search engine Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise, the indicated compression pressures may
not be valid for diagnosis purposes.
(1) Clean the spark plug recesses with compressed
air.
(2) Remove the spark plugs.
(3) Secure the throttle in the wide-open position.
(4) Disconnect the ignition coil.
(5) Insert a compression pressure gauge and rotate
the engine with the engine starter motor for three
revolutions.
(6) Record the compression pressure on the third
revolution. Continue the test for the remaining cylin-
ders.
Refer to Engine Specifications for the correct
engine compression pressures.
CYLINDER HEAD GASKET FAILURE DIAGNOSIS
A cylinder head gasket leak can be located between
adjacent cylinders or between a cylinder and the
adjacent water jacket.
²Possible indications of the cylinder head gasket
leaking between adjacent cylinders are:
²Loss of engine power
²Engine misfiring
²Poor fuel economy
²Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
²Engine overheating
²Loss of coolant
²Excessive steam (white smoke) emitting from
exhaust
²Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test in this
section. An engine cylinder head gasket leaking
between adjacent cylinders will result in approxi-
mately a 50±70% reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING WITH COOLANT PRES-
SURE CAP REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure
cap. Start the engine and allow it to warm up until
thermostat opens.
If a large combustion/compression pressure leak
exists, bubbles will be visible in the coolant.COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE PRESSURE BUILT UP, BY CONTINUOUS
ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to
pressure cap neck. Start the engine and observe the
tester's pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also
be checked by using Bloc-Chek Kit C-3685-A or
equivalent. Perform test following the procedures
supplied with the tool kit.
CYLINDER COMBUSTION PRESSURE LEAKAGE
TEST
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
²Exhaust and intake valve leaks (improper seat-
ing)
²Leaks between adjacent cylinders or into water
jacket
²Any causes for combustion/compression pressure
loss
WARNING: DO NOT REMOVE THE RADIATOR CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE.
SERIOUS BURNS FROM HOT COOLANT CAN
OCCUR.
Check the coolant level and fill as required. DO
NOT install the radiator cap.
Start and operate the engine until it attains nor-
mal operating temperature, then turn OFF the
engine.
Remove the spark plugs.
Remove the oil filler cap.
Remove the air cleaner.
Calibrate the tester according to the manufactur-
er's instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1,379
kPa (200 psi) maximum and 552 kPa (80 psi) recom-
mended.
Perform the test procedure on each cylinder accord-
ing to the tester manufacturer's instructions. While
testing, listen for pressurized air escaping through
the throttle body, tailpipe or oil filler cap opening.
Check for bubbles in the radiator coolant.
9 - 146 5.9L ENGINEDN
DIAGNOSIS AND TESTING (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)