CONDITION POSSIBLE CAUSES CORRECTION
MAIN BEARING NOISE 1. Insufficient oil supply 1. Check engine oil level.
2. Low oil pressure 2. Check engine oil level. If ok,
Perform oil pressure test. (Refer to
9 - ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING)
3. Thin or diluted oil 3. Change oil to correct viscosity.
4. Excessive main bearing
clearance4. Measure bearings for correct
clearance. Repair as necessary
5. Excessive end play 5. Check crankshaft thrust bearing
for excessive wear on flanges
6. Crankshaft main journal out of
round or worn6. Grind journals or replace
crankshaft
7. Loose flywheel or torque
converter7. Inspect crankshaft, flexplate/
flywheel and bolts for damage.
Tighten to correct torque
LOW OIL PRESSURE 1. Low oil level 1. Check oil level and fill if
necessary
2. Faulty oil pressure sending unit 2. Install new sending unit
3. Clogged oil filter 3. Install new oil filter
4. Worn oil pump 4. Replace oil pump assembly.
5. Thin or diluted oil 5. Change oil to correct viscosity.
6. Excessive bearing clearance 6. Measure bearings for correct
clearance
7. Oil pump relief valve stuck 7. Remove valve to inspect, clean
and reinstall
8. Oil pickup tube loose, broken,
bent or clogged8. Inspect oil pickup tube and pump,
and clean or replace if necessary
9. Oil pump cover warped or
cracked9. Install new oil pump
OIL LEAKS 1. Misaligned or deteriorated
gaskets1. Replace gasket
2. Loose fastener, broken or porous
metal part2. Tighten, repair or replace the part
3. Front or rear crankshaft oil seal
leaking3. Replace seal
4. Leaking oil gallery plug or cup
plug4. Remove and reseal threaded
plug. Replace cup style plug
DRENGINE - 5.7L 9 - 189
ENGINE - 5.7L (Continued)
VALVE SPRING
DESCRIPTION SPECIFICATION
Spring Force (Valve
Closed)
Intake and Exhaust 422.0 N @ 46.0 mm
(95lbs. @ 1.81 in.)
Spring Force (Valve
Open)
Intake and Exhaust @ 33.5 mm
Number of Coils
Intake and Exhaust 7.4
Wire Diameter
Intake and Exhaust 5.39 ý 4.52 mm
(0.212 - 0.177 in.)
Installed Height (Spring
Seat to Bottom of
Retainer)
Intake and Exhaust 46.0 mm (1.81 in.)
OIL PUMP
DESCRIPTION SPECIFICATION
Clearance Over Rotors
(MAX)0.095 mm (0.0038 in.)
Outer Rotor to Pump
Body Clearance (MAX).235 mm (.009 in.)
Tip Clearance Between
Rotors (MAX)0.150 mm (0.006 in.)
OIL PRESSURE
SPECIFICATION SPECIFICATION
At Curb Idle Speed
(MIN)*25 kPa (4 psi)
@ 3000 rpm 170 - 758 kPa (25 - 110
psi)
* CAUTION: If pressure is zero at curb idle, DO
NOT run engine
TORQUE
TORQUE CHART 5.7L ENGINE
DESCRIPTION N´m Ft. In.
Lbs. Lbs.
Block Pipe Plugs
(1/4 NPT)20 Ð 177
(3/8 NPT) 27 Ð 240
Camshaft SprocketÐBolt 122 90 Ð
Camshaft Tensioner
PlateÐBolts28 Ð 250
Timing Chain Case CoverÐ
Bolts28 Ð 250
Lifting Stud 55 40 Ð
Connecting Rod CapÐBolts 21
plus
90É
Turn15
plus
90É
TurnÐ
Main Bearing CapÐBolts
M-1227
plus
90É
TurnÐÐ
Crossbolts
M-828 Ð Ð
Cylinder HeadÐBolts
M-12 Bolts
Step 1 34 25 Ð
Step 2 54 40 Ð
Step 3 Turn
90ÉTurn
90ÉÐ
M-8 Bolts Ð
Step 1 20 15 Ð
Step 2 34 25 Ð
Cylinder Head CoverÐBolts 8 Ð 70
Exhaust Manifold to Cylinder
Head25 Ð 220
Flexplate to crankshaftÐBolts 95 70 Ð
Flywheel to crankshaftÐBolts 75 55 Ð
Front InsulatorÐThrough
bolt/nut95 70 Ð
Front Insulator to Support
Bracket
ÐStud Nut (4WD) 41 30 Ð
ÐThrough Bolt/Nut (4WD) 102 75 Ð
Front Insulator to BlockÐ
Bolts (2WD)95 70 Ð
DRENGINE - 5.7L 9 - 195
ENGINE - 5.7L (Continued)
CRANKSHAFT OIL SEAL -
REAR
DIAGNOSIS AND TESTING - REAR SEAL AREA
LEAKS
Since it is sometimes difficult to determine the
source of an oil leak in the rear seal area of the
engine, a more involved inspection is necessary. The
following steps should be followed to help pinpoint
the source of the leak.
If the leakage occurs at the crankshaft rear oil seal
area:
(1) Disconnect the battery.
(2) Raise the vehicle.
(3) Remove torque converter or clutch housing
cover and inspect rear of block for evidence of oil.
Use a black light to check for the oil leak:
(a) Circular spray pattern generally indicates
seal leakage or crankshaft damage.
(b) Where leakage tends to run straight down,
possible causes are a porous block, camshaft bore
cup plugs, oil galley pipe plugs, oil filter runoff,
and main bearing cap to cylinder block mating sur-
faces. See Engine, for proper repair procedures of
these items.
(4) If no leaks are detected, pressurized the crank-
case as outlined in the section, Inspection (Engine oil
Leaks in general)
CAUTION: Do not exceed 20.6 kPa (3 psi).
(5) If the leak is not detected, very slowly turn the
crankshaft and watch for leakage. If a leak is
detected between the crankshaft and seal while
slowly turning the crankshaft, it is possible the
crankshaft seal surface is damaged. The seal area on
the crankshaft could have minor nicks or scratches
that can be polished out with emery cloth.
CAUTION: Use extreme caution when crankshaft
polishing is necessary to remove minor nicks or
scratches. The crankshaft seal flange is specially
machined to complement the function of the rear oil
seal.
(6) For bubbles that remain steady with shaft
rotation, no further inspection can be done until dis-
assembled. (Refer to 9 - ENGINE - DIAGNOSIS AND
TESTING), under the Oil Leak row, for components
inspections on possible causes and corrections.
(7) After the oil leak root cause and appropriate
corrective action have been identified, (Refer to 9 -
ENGINE/ENGINE BLOCK/CRANKSHAFT OIL
SEAL - REAR - REMOVAL).
REMOVAL
NOTE: This procedure can be performed in vehicle.
(1) If being preformed in vehicle, remove the
transmission.
(2) Remove the flexplate (Refer to 9 - ENGINE/
ENGINE BLOCK/FLEX PLATE - REMOVAL).
NOTE: The crankshaft oil seal CAN NOT be reused
after removal.
NOTE: The crankshaft rear oil seal remover Special
Tool 8506 must be installed deeply into the seal.
Continue to tighten the removal tool into the seal
until the tool can not be turned farther. Failure to
install tool correctly the first time will cause tool to
pull free of seal without removing seal from engine.
(3) Using Special Tool 8506, remove the crankshaft
rear oil seal.
INSTALLATION
CAUTION: The rear seal must be installed dry for
proper operation. Do not lubricate the seal lip or
outer edge.
(1) Position the plastic seal guide onto the crank-
shaft rear face. Then position the crankshaft rear oil
seal onto the guide.
(2) Using Special Tools 8349 Crankshaft Rear Oil
Seal Installer and C-4171 Driver Handle, with a
hammer, tap the seal into place. Continue to tap on
the driver handle until the seal installer seats
against the cylinder block crankshaft bore.
(3) Install the flexplate.
(4) Install the transmission.
CRANKSHAFT REAR OIL SEAL
RETAINER
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove the transmission.
(3) Remove the drive plate / flywheel.
(4) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(5) Remove the rear oil seal retainer mounting
bolts.
(6) Carefully remove the retainer from the engine
block.
DRENGINE - 5.7L 9 - 209
INSTALLATION
(1) Throughly clean all gasket resdue from the
engine block.
(2) Use extream care and clean all gasket resdue
from the retainer.
(3) Position the gasket onto the retainer.
(4) Position the retainer onto the engine block.
(5) Install the retainer mounting bolts. Tighten the
bolts to 15 N´m (132 in. lbs.) using a crisscross pat-
tern, starting with the bolt on the lower right.
(6) Install a new rear seal(Refer to 9 - ENGINE/
ENGINE BLOCK/CRANKSHAFT OIL SEAL - REAR
- INSTALLATION).
(7) Install the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - INSTALLATION).
(8) Install the drive plate / flywheel.
(9) Install the transmission.
(10) Check and verify engine oil level.
(11) Start engine and check for leaks.
FLEX PLATE
REMOVAL
(1) Remove the transmission.
(2) Remove the bolts and flexplate.
INSTALLATION
(1) Position the flexplate or flywheel onto the
crankshaft and install the bolts hand tight.
(2)For automatic transmissions:Tighten the
flexplate retaining bolts to 95 N´m (70 ft. lbs.).
(3)For manual transmissions:Tighten the fly-
wheel retaining bolts to 75 N´m (55 ft. lbs.).
(4) Install the transmission.
HYDRAULIC TAPPETS
DIAGNOSIS AND TESTING - 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 207-552 kPa (30-70 psi) at 3,000 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 two con-
ditions 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.
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 create 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 usu-
ally more than one tappet will be noisy. When oil level
and leaks have been corrected, operate the engine at
fast idle. Run engine for a sufficient 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 excessive
leak-down around the unit plunger, or by the plunger
partially sticking in the tappet body cylinder. The tap-
pet should be replaced. A heavy click is caused by a tap-
pet check valve not seating, or by foreign particles
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 clear-
ance between the valve stem and rocker arm as valve
closes. In either case, tappet assembly should be
removed for inspection 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. If more than one tappet seems to be
noisy, it's probably not the tappets.
9 - 210 ENGINE - 5.7LDR
CRANKSHAFT REAR OIL SEAL RETAINER (Continued)
(10) Drain engine oil. Remove and discard the oil
filter (Refer to 9 - ENGINE/LUBRICATION/OIL FIL-
TER - REMOVAL).
(11) Install the drain plug. Tighten the plug to 50
N´m (37 ft. lbs.) torque.
(12) Install a new oil filter (Refer to 9 - ENGINE/
LUBRICATION/OIL FILTER - INSTALLATION).
(13) Fill engine crankcase with the specified
amount and grade of oil (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES - SPECIFICA-
TIONS).
(14) Connect the negative cable(s) to the battery.
(15) Start the engine and check for any leaks.
REMOVAL
REMOVAL - ENGINE
(1) Disconnect both battery negative cables.
(2) Disconnect engine grid heater harness at grid
heater relays.
(3) Disconnect electrical connections from rear of
alternator.
(4) Recover A/C refrigerant. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - STAN-
DARD PROCEDURE).
(5) Raise vehicle on a hoist.
(6) Drain engine coolant (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(7) Remove engine oil drain plug and drain engine
oil.
(8) Reinstall drain plug. Tighten to 50N´m (37 ft.
lbs.) torque.
(9) Lower the vehicle.
(10) Remove fan/drive assembly. Refer to Section 7
± Fan/Drive Removal
(11) Remove radiator upper hose.
(12) Remove upper fan shroud mounting bolts.
(13) Disconnect the coolant recovery bottle hose
from the radiator fill neck and remove bottle.
(14) Using a 36mm wrench, remove viscous fan/
drive assembly. (Refer to 7 - COOLING/ENGINE/RA-
DIATOR FAN - REMOVAL).
(15) Remove cooling fan and shroud together.
(16) Disconnect heater core supply and return
hoses from the cylinder head fitting and coolant pipe.
(17) Raise vehicle on a hoist.
(18) Remove transmission and transfer case (if
equipped).
(19) Disconnect exhaust pipe from turbocharger
extension pipe.
(20) Disconnect engine harness to vehicle harness
connectors.
(21) Remove starter motor (Refer to 8 - ELECTRI-
CAL/STARTING/STARTER MOTOR - REMOVAL).(22) Remove flywheel/flexplate.
(23) Remove transmission adapter
(24) Disconnect A/C suction/discharge hose from
the rear of the A/C compressor.
(25) Lower vehicle.
(26) Disconnect lower radiator hose from radiator
outlet.
(27) Automatic transmission models:
(28) Disconnect transmission oil cooler lines from
in front of radiator using special tool #6931
(29) Remove radiator. (Refer to 7 - COOLING/EN-
GINE/RADIATOR - REMOVAL).
(30) If A/C equipped, disconnect A/C condenser
refrigerant lines.
(31) Disconnect charge air cooler piping.
(32) Remove charge air cooler mounting bolts.
(33) Remove charge air cooler (and A/C condenser
if equipped) from vehicle.
(34) Remove damper and speed indicator ring from
front of engine.
(35) Disconnect engine block heater connector.
(36) Disconnect A/C compressor and pressure sen-
sor electrical connectors.
(37) Remove the passenger battery ground cable
from the engine block. Remove the driver side bat-
tery ground cable from the engine block.
(38) Remove power steering pump from engine by
removing 3 bolts.
(39) Remove accelerator linkage cover.
(40) Disconnect cables from on-engine APPS.
(41) Disconnect the ECM power connector.
(42) Disconnect the ECM ground wire from the
hydroform screw.
(43) Disconnect the fuel supply and return hoses.
(44) Remove the cylinder head cover. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(45) Disconnect the 3 injector harness connectors
at the rocker housing. Disconnect the wire harnesses
from the injectors.
(46) Remove the rear engine lift bracket.
(47) Remove cylinder #4, #5, and #6 intake and
exhaust rocker arms, pedestals, and push tubes. Note
the original location for re-assembly.
(48) Loosen #6 fuel line shield bolts and rotate
shield out of the way.
(49) Remove cylinder #5 and #6 high pressure fuel
lines. Remove the fuel connector tube nut and fuel
connector tube. Remove cylinder #5 and #6 fuel injec-
tor.
(50) Remove rocker housing.
DRENGINE 5.9L DIESEL 9 - 241
ENGINE 5.9L DIESEL (Continued)
(8) Replace injector o-ring and sealing washer on
injectors #5 and #6. Install injectors and torque using
the following steps:
²Step 1ÐInstall injector hold-down capscrews
and torque to 5 N´m (44 in. lbs.) torque.
²Step 2ÐLoosen injector hold-down capscrews.
²Step 3ÐInstall HPC connector tube and nut.
Torque nut to 15 N´m (11 ft. lbs.) torque.
²Step 4ÐTorque injector hold-down capscrews to
10 N´m (89 in. lbs.) torque.
²Step 5ÐTorque HPC connector tube nut to 50
N´m (37 ft. lbs.) torque.
(9) Install #5 and #6 high pressure fuel lines. Fol-
low correct torque sequence per section 14. Torque
fuel line fittings to 30 N-m (22 ft-lb). Torque brace
capscrew to 24 N-m (18 ft-lb).
(10) Install rear engine lift bracket. Torque to 77
N-m (57 ft-lb).
(11) Install push tubes, rocker arms, and pedestals
for cylinders #4, #5, and #6. Torque the mounting
bolts to 36 N-m (27 ft-lbs).
(12) Reset valve lash on cylinders #4, #5, and #6.
Torque adjusting nuts to 24 N-m (18 ft-lbs).
(13) Install cylinder head cover. Torque to 24 N-m
(18 ft-lbs).(Refer to 9 - ENGINE/CYLINDER HEAD -
INSTALLATION).
(14) Connect breather tube and lube oil drain tube
to breather housing cover. Install breather housing.
Torque capscrews to 24 N-m (18 ft-lbs)
(15) Connect fuel supply and return hoses.
(16) Connect ECM ground to hydroform screw.
Connect ECM power connector.
(17) Install the APPS cable(s) to the APPS. Install
the throttle linkage cover.
(18) Install the power steering pump.
(19) Install the damper and speed indicator ring.
Torque to 40 N-m (30 ft-lb) plus 60 degrees.
(20) Connect the engine block heater connection.
(21) Connect the A/C compressor and pressure sen-
sor connectors
(22) Install the charge air cooler and a/c condenser
(if equipped). Install and tighten the charge air
cooler mounting bolts to 2 N-m (17 in-lbs).
(23) Connect the charge air cooler piping. Torque
all clamps to 8 N-m (72 in-lbs).
(24) Connect the a/c refrigerant lines to the a/c
condenser (if equipped).
(25) Install the radiator upper support panel.
(26) Install radiator.
(27) Connect the transmission quick-connect oil
cooler lines.(28) Raise vehicle.
(29) Connect a/c compressor suction/discharge hose
(if equipped).
(30) Install the radiator lower hose and clamps.
(31) Install the battery negative cables to the
engine block on the driver and passenger side.
(32) Install the transmission adapter with a new
camshaft rectangular ring seal. Torque to 77 N-m (57
ft-lb).
(33) Install the flywheel/flexplate. Torque to 137
N-m (101 ft-lb).
(34) Install the starter motor. Torque to 43 N-m
(32 ft-lb). (Refer to 8 - ELECTRICAL/STARTING/
STARTER MOTOR - INSTALLATION).
(35) Connect engine to vehicle harness connectors.
(36) Install transmission and transfer case (if
equipped).
(37) Connect the exhaust pipe to the turbocharger
elbow.
(38) Connect the transmission auxiliary oil cooler
lines (if equipped).
(39) Lower the vehicle.
(40) Connect the heater core supply and return
hoses.
(41) Install the cooling fan and upper fan shroud
at the same time. (Refer to 7 - COOLING/ENGINE/
RADIATOR FAN - INSTALLATION).
(42) Install the coolant recovery bottle.
(43) Install the windshield washer bottle.
(44) Install the upper radiator hose and clamps.
(45) Raise vehicle.
(46) Connect electronically controlled fan drive
wire harness. Install lower radiator fan shroud.
(47) Change oil filter and install new engine oil.
(48) Fill the cooling system with coolant. (Refer to
7 - COOLING - STANDARD PROCEDURE).
(49) Connect grid heater harness at grid heater
relays.
(50) Connect electrical connections to rear of alter-
nator.
(51) Start the engine and inspect for engine oil,
coolant, and fuel leaks.
INSTALLATIONÐCRANKCASE BREATHER
(1) Install a new o-ring onto the breather element.
(2) Lubricate o-ring and install into cylinder head
cover. Torque capscrews to 10 N´m (89 in. lbs.).
(3) Connect breather tube and lube oil drain tube.
(4) Install breather cover (Fig. 4). Torque to 24
N´m (18 ft. lbs.)
(5) Install oil fill cap.
DRENGINE 5.9L DIESEL 9 - 243
ENGINE 5.9L DIESEL (Continued)
(32) Disconnect fuel heater, water in fuel sensor,
and fuel lift pump connectors.
(33) Remove the fuel filter assembly-to-cylinder
head bolts and remove filter assembly from vehicle.
(34) Remove wire harness P-clip from cylinder
head (located behind filter housing).
(35) Remove the cylinder head cover(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(36) Disconnect rocker housing injector harness
connectors.
(37) Remove injector harness nuts from injectors.
(38) Remove the rocker levers (Fig. 11), cross
heads and push rods (Fig. 12). Mark each component
so they can be installed in their original positions.
NOTE: The #5 cylinder exhaust and the #6 cylinder
intake and exhaust push rods are removed by lift-
ing them up and through the provided cowl panel
access holes. Remove the rubber plugs to expose
these relief holes.
(39) Remove the fuel return line and banjo bolt at
the rear of the cylinder head. Be careful not to drop
the two (2) sealing washers.
(40) Remove the fuel injectors (Refer to 14 - FUEL
SYSTEM/FUEL INJECTION/FUEL INJECTOR -
REMOVAL).
(41) Remove rocker housing bolts and rocker hous-
ing and gasket.(42) Reinstall the engine lift bracket at the rear of
cylinder head. Torque to 77 N´m (57 ft. lbs.).
(43) Remove twenty six (26) cylinder head-to-block
bolts.
(44) Attach an engine lift crane to engine lift
brackets and lift cylinder head off engine and out of
vehicle.
(45) Remove the head gasket and inspect for fail-
ure.
CLEANING
CLEANINGÐCYLINDER HEAD
CAUTION: Do not wire brush head surface while
fuel injectors are still installed. Fuel injector dam-
age can result.
Remove fuel injector before cleaning (if not already
removed during cylinder head removal).
Clean the carbon from the injector nozzle seat with
a nylon or brass brush.
Scrape the gasket residue from all gasket surfaces.
Wash the cylinder head in hot soapy water solution
(88ÉC or 140ÉF).
After rinsing, use compressed air to dry the cylin-
der head.
Polish the gasket surface with 400 grit paper. Use
an orbital sander or sanding block to maintain a flat
surface.
CLEANINGÐCROSSHEADS
Clean all crossheads in a suitable solvent. If neces-
sary, use a wire brush or wheel to remove stubborn
deposits. Rinse in hot water and blow dry with com-
pressed air.
Fig. 11 Rocker Arm and Pedestal Removal
1 - ROCKER ARM
2 - PEDESTAL
Fig. 12 Push Rod Removal
DRENGINE 5.9L DIESEL 9 - 251
CYLINDER HEAD (Continued)
CLEANINGÐPUSHRODS
Clean the pushrods in a suitable solvent. Rinse in
hot water and blow dry with compressed air. If nec-
essary, use a wire brush or wheel to remove stubborn
deposits.
INSPECTION
INSPECTION - CYLINDER HEAD
Inspect the cylinder head for cracks in the combus-
tion surface. Pressure test any cylinder head that is
visibly cracked. A cylinder head that is cracked
between the injector bore and valve seat can be pres-
sure tested and reused if OK; however, if the crack
extendsintothe valve seat insert bore, the cylinder
headmustbe replaced.
Visually inspect the cylinder block and head com-
bustion surfaces for localized dips or imperfections.
Check the cylinder head and block combustion sur-
faces for overall out-of-flatness. If either the visual or
manual inspection exceeds the limits, then the head
or block must be surfaced.
Check the top surface for damage caused by the
cylinder head gasket leaking between cylinders.
Inspect the block and head surface for nicks, ero-
sion, etc.
Check the head distortion. Maximum overall vari-
ation end to end is 0.305 mm (0.012 inch) (Fig. 13),
and maximum overall variation side to side 0.076
mm ( .003 in.).
DO NOT proceed with the in-chassis overhaul if
the cylinder head or block surface is damaged or not
flat (within specifications).
Check block surface for distortion. Maximum vari-
ation end-to-end is 0.076 mm ( .003 in.), side-to-side
0.051 mm (.002).Visually inspect the cylinder head bolts for dam-
aged threads, corroded/pitted surfaces, or a reduced
diameter due to bolt stretching.
If the bolts are not damaged, their ªfree lengthº
should be measured using the cap screw stretch
gauge provided with the replacement head gasket.
Place the head of the bolt against the base of the slot
and align the bolt with the straight edge of gauge
(Fig. 14). If the end of the bolt touches the foot of the
gauge, the boltmustbe discarded.The maximum
bolt free length is 132.1 mm (5.200 in.).
INSPECTIONÐCROSSHEADS
Inspect the crossheads for cracks and/or excessive
wear on rocker lever and valve tip mating surfaces
(Fig. 15). Replace any crossheads that exhibit abnor-
mal wear or cracks.
Fig. 13 Cylinder Head Combustion Deck Face
1 - STRAIGHT EDGE
2 - FEELER GAUGE
Fig. 14 Head Bolt Stretch Gauge
Fig. 15 Inspecting Crosshead for Cracks
9 - 252 ENGINE 5.9L DIESELDR
CYLINDER HEAD (Continued)