1998 DODGE RAM 1500 Engine

VALVE SPRINGS
REMOVAL
(1) Disconnect negative battery cable.
(2) Remove air cleaner assembly.
(3) Remove air intake resonator.
(4) Remove spark plug cables.
(5) Remove ignition coil connectors (Fig. 6).
(6) Remove ignition coils.
(7) Remove one spark plug.
(8) Remove valve cover.
CAUTION: The piston must be at TDC, and both
valves closed on the cylinder to be serviced.
NOTE: If removing intake valve spring, install spe-
cial tool# 9070, pushrod retaining plate, to retain
the intake pushrods.
(9) Remove exhaust/intake rocker arm shafts.
(10) Install spring compressor, special tool# 9065.
NOTE: All valve springs and seals are removed in
the same manner.(11) Charge cylinder with air.
NOTE: Tap the top of the valve spring retainer to
loosen the spring retainers locks.
(12) Compress valve spring and remove valve
retainer locks.
(13) Release spring compressor and remove valve
spring.
NOTE: The valve springs are interchangeable
between intake and exhaust.
(14) Remove valve seal.
INSTALLATION
(1) Install valve seal.
(2) Install valve spring.
(3) Using special tool# 9065, compress valve spring
and install valve spring retainer and locks.
(4) Release air charge in cylinder.
(5) Remove spring compressor tool # 9065.
CAUTION: Verify that the pushrods are fully seated
into lifter and rocker arm. Recheck after rocker arm
shaft has been torqued to specification.
(6) Install rocker arm shaft and pushrods(Refer to
9 - ENGINE/CYLINDER HEAD/ROCKER ARM /
ADJUSTER ASSY - INSTALLATION).
(7) Tighten the rocker shaft bolts to 22 N´m (195
in. lbs.) torque,using the following sequence:Center,
center-right, center-left, right, left.
(8) Remove special tool# 9070, pushrod retaining
plate, if used.
(9) Install cylinder head cover.
(10) Tighten cylinder head cover bolts and double
ended studs(Refer to 9 - ENGINE/CYLINDER
HEAD/CYLINDER HEAD COVER(S) - INSTALLA-
TION).
(11) Install spark plugs.
(12) Install ignition coil on plug, and torque fas-
teners to 12 N´m (105 in. lbs)
(13) Install ignition coil connectors.
(14) Install spark plug cables.
(15) Install air intake resonator.
(16) Install air cleaner assembly.
(17) Connect negative battery cable.
Fig. 6 IGNITION COIL R/I Ð 5.7L V-8
1 - SLIDE LOCK (SLIDE OUTWARD TO UNLOCK)
2 - SPARK PLUG CABLE (TO OPPOSITE CYLINDER BANK
SPARK PLUG)
3 - RELEASE LOCK / TAB (PUSH HERE)
4 - ELEC. CONNECTOR
5 - IGNITION COIL
6 - COIL MOUNTING BOLTS (2)
7 - SPARK PLUG CABLE (TO OPPOSITE CYLINDER BANK
IGNITION COIL)
9 - 204 ENGINE - 5.7LDR

ENGINE BLOCK
CLEANING
Thoroughly clean the oil pan and engine block gas-
ket surfaces.
Use compressed air to clean out:
²The galley at the oil filter adaptor hole.
²The front and rear oil galley holes.
²The feed holes for the crankshaft main bearings.
Once the block has been completely cleaned, apply
Loctite PST pipe sealant with Teflon 592 to the
threads of the front and rear oil galley plugs. Tighten
the 1/4 inch NPT plugs to 20 N´m (177 in. lbs.)
torque. Tighten the 3/8 inch NPT plugs to 27 N´m
(240 in. lbs.) torque.
INSPECTION
(1) It is mandatory to use a dial bore gauge to
measure each cylinder bore diameter. To correctly
select the proper size piston, a cylinder bore gauge,
capable of reading in 0.003 mm (.0001 in.) INCRE-
MENTS is required. If a bore gauge is not available,
do not use an inside micrometer (Fig. 7).
(2) Measure the inside diameter of the cylinder
bore at three levels below top of bore. Start perpen-
dicular (across or at 90 degrees) to the axis of the
crankshaft and then take two additional reading.
(3) Measure the cylinder bore diameter crosswise
to the cylinder block near the top of the bore. Repeatthe measurement near the middle of the bore, then
repeat the measurement near the bottom of the bore.
(4) Determine taper by subtracting the smaller
diameter from the larger diameter.
(5) Rotate measuring device 90É and repeat steps
above.
(6) Determine out-of-roundness by comparing the
difference between each measurement.
(7) If cylinder bore taper does not exceed 0.025
mm (0.001 inch) and out-of-roundness does not
exceed 0.025 mm (0.001 inch), the cylinder bore can
be honed. If the cylinder bore taper or out- of-round
condition exceeds these maximum limits, the cylinder
block must be replaced. A slight amount of taper
always exists in the cylinder bore after the engine
has been in use for a period of time.CAMSHAFT & BEARINGS (IN
BLOCK)
REMOVAL
REMOVAL - CAMSHAFT CORE HOLE PLUG
CAUTION: Do not damage the rear surface of the
camshaft or the core plug sealing surface, when
removing the core plug.
(1) Remove the rear cam bearing core plug.
REMOVAL - CAMSHAFT
(1) Remove the battery negative cable.
(2) Remove the air cleaner assembly.
(3) Drain coolant.
(4) Remove the accessory drive belt.
(5) Remove the generator.
(6) Remove the A/C compressor, and set aside
(7) Remove the radiator (Refer to 7 - COOLING/
ENGINE/RADIATOR - REMOVAL).
(8) Remove intake manifold(Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - REMOVAL).
(9) Remove cylinder head covers(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(10) Remove both left and right cylinder heads(Re-
fer to 9 - ENGINE/CYLINDER HEAD - REMOVAL) .
(11) Remove the oil pan(Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(12) Remove timing case cover(Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(13) Remove the oil pick up tube.
(14) Remove the oil pump(Refer to 9 - ENGINE/
LUBRICATION/OIL PUMP - REMOVAL).
Fig. 7 BORE GAUGE-TYPICAL
1 - FRONT
2 - BORE GAUGE
3 - CYLINDER BORE
4 - 38 MM (1.5 in)
DRENGINE - 5.7L 9 - 205

(15) Remove timing chain(Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - REMOVAL).
(16) Remove camshaft tensioner/thrust plate
assembly.
NOTE: Identify tappets to ensure installation in orig-
inal location.
(17) Remove the retainer assembly and tappets.
(18) Install a long bolt into front of camshaft to aid
in removal of the camshaft. Remove camshaft, being
careful not to damage cam bearings with the cam
lobes.
INSPECTION
(1) The cam bearings are not serviceable. Do not
attempt to replace cam bearings for any reason.
INSTALLATION
INSTALLATION - CAMSHAFT CORE HOLE PLUG
CAUTION: The new core hole plug must be installed
to the proper depth or camshaft damage could
develope. The plug must be installed squarely in
the bore.
(1) Install a new core hole plug at the rear of cam-
shaft, using special tool # 9048. Clean plug and apply
mopartlock and seal adhesive to the edge of the
plug, before installing. The plug must be installed to
a depth of+/-0.25mm from the end of the machined
bevel, that is the end of the bevel that is closest to
the cam bearing.
INSTALLATION - CAMSHAFT
(1) Lubricate camshaft lobes and camshaft bearing
journals and insert the camshaft
(2) Install camshaft Tensioner plate assembly.
Tighten bolts to 28 N´m (250 in. lbs.) torque.
(3) Install timing chain and sprockets(Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT/CHAIN
AND SPROCKETS - INSTALLATION) .
(4) Measure camshaft end play(Refer to 9 -
ENGINE - SPECIFICATIONS). If not within limits
install a new thrust plate.
(5) Install the oil pump(Refer to 9 - ENGINE/LU-
BRICATION/OIL PUMP - INSTALLATION).
(6) Install the oil pick up tube.
(7) Each tappet reused must be installed in the
same position from which it was removed.When
camshaft is replaced, all of the tappets must be
replaced.(8) Install the tappets and retainer assembly(Refer
to 9 - ENGINE/ENGINE BLOCK/HYDRAULIC LIFT-
ERS (CAM IN BLOCK) - INSTALLATION).
(9) Install both left and right cylinder heads(Refer
to 9 - ENGINE/CYLINDER HEAD - INSTALLA-
TION) .
(10) Install pushrods
(11) Install rocker arms(Refer to 9 - ENGINE/CYL-
INDER HEAD/ROCKER ARM / ADJUSTER ASSY -
INSTALLATION).
(12) Install timing case cover(Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(13) Install the oil pan(Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - INSTALLATION).
(14) Install cylinder head covers(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(15) Install intake manifold(Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - INSTALLA-
TION).
(16) Install the A/C compressor, and set aside
(17) Install the generator.
(18) Install the accessory drive belt.
(19) Install the radiator (Refer to 7 - COOLING/
ENGINE/RADIATOR - INSTALLATION).
(20) Install the air cleaner assembly.
(21) Install the battery negative cable.
(22) Refill coolant.
(23) Refill engine oil.
(24) Start engine and check for leaks.
CRANKSHAFT
REMOVAL
(1) Remove the vibration damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
REMOVAL).
(2) Remove the oil pan(Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(3) Remove the oil pump pickup.
(4) Remove the windage tray/oil pan gasket.
(5) Remove the timing chain cover(Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(6) Remove the oil pump(Refer to 9 - ENGINE/LU-
BRICATION/OIL PUMP - REMOVAL).
(7) Remove the timing drive(Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - REMOVAL).
(8) Identify rod bearing caps before removal.
Remove rod bearing caps with bearings.
(9) Identify main bearing caps before removal.
Remove main bearing caps and bearings one at a
time.
9 - 206 ENGINE - 5.7LDR
CAMSHAFT & BEARINGS (IN BLOCK) (Continued)

(10) Remove the thrust washers.
(11) Remove the rear oil seal retainer(Refer to 9 -
ENGINE/ENGINE BLOCK/CRANKSHAFT REAR
OIL SEAL RETAINE - REMOVAL).
(12) Remove the crankshaft out of the block.
(13) Remove and discard the crankshaft rear oil
seal.
(14) Remove and discard the front crankshaft oil
seal.
INSTALLATION
(1) Select the proper main bearings(Refer to 9 -
ENGINE/ENGINE BLOCK/CRANKSHAFT MAIN
BEARINGS - STANDARD PROCEDURE) .
(2) Install main bearings in block and caps, and
lubricate bearings.
(3) Position the crankshaft into the cylinder block.
(4) Install the thrust washers.
NOTE: The main cap crossbolts are torqued after
final torque of the main cap bolts. Always use a
new washer/seal on crossbolts.
(5) Clean and oil all cap bolts. Install all main
bearing caps. Install all cap bolts and alternately
tighten in two steps using the following sequence
(Fig. 8).
²Step1±27N´m(20ft. lbs.) torque.
²Step2±Turnmain cap bolts an additional 90É.(6) Install the crossbolts with new washer/gasket.
Starting with crossbolt A (Fig. 8) torque each cross-
bolt to 28 N´m torque.
(7) Repeat crossbolt torque procedure.
(8) Measure crankshaft end play(Refer to 9 -
ENGINE/ENGINE BLOCK/CRANKSHAFT MAIN
BEARINGS - STANDARD PROCEDURE) .
(9) Position the connecting rods onto the crank-
shaft and install the rod bearing caps(Refer to 9 -
ENGINE/ENGINE BLOCK/PISTON & CONNECT-
ING ROD - INSTALLATION).
(10) Install timing drive(Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - INSTALLATION) .
(11) Install oil pump (Refer to 9 - ENGINE/LU-
BRICATION/OIL PUMP - INSTALLATION).
(12) Install the timing chain cover(Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(13) Install the rear main seal and retainer(Refer
to 9 - ENGINE/ENGINE BLOCK/CRANKSHAFT
REAR OIL SEAL RETAINE - INSTALLATION).
(14) Install the windage tray/oil pan gasket.
(15) Install the oil pick up tube.
(16) Install the oil pan(Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - INSTALLATION).
(17) Install the vibration damper(Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
INSTALLATION).
(18) Install the engine(Refer to 9 - ENGINE -
INSTALLATION).
CRANKSHAFT MAIN
BEARINGS
STANDARD PROCEDURE - CRANKSHAFT MAIN
BEARING - FITTING
MAIN BEARING JOURNAL DIAMETER
(CRANKSHAFT REMOVED)
Crankshaft removed from the cylinder block.
Clean the oil off the main bearing journal.
Determine the maximum diameter of the journal
with a micrometer. Measure at two locations 90É
apart at each end of the journal.
The maximum allowable taper is 0.008mm (0.0004
inch.) and maximum out of round is 0.005mm (0.0002
inch). Compare the measured diameter with the jour-
nal diameter specification (Main Bearing Fitting
Chart). Select inserts required to obtain the specified
bearing-to-journal clearance.
CRANKSHAFT MAIN BEARING SELECTION
The main bearings are ªselect fitº to achieve proper
oil clearances. For main bearing selection, the crank-
Fig. 8 MAINCAP TIGHTENING SEQUENCE
1 - Stud Location
DRENGINE - 5.7L 9 - 207
CRANKSHAFT (Continued)

shaft counterweight has grade identification marks
stamped into it. These marks are read from left to
right, corresponding with journal number 1, 2, 3, 4
and 5.
NOTE: Service main bearings are coded. These
codes identify what size (grade) the bearing is.
MAIN BEARING SELECTION CHART - 5.7L
GRADE SIZE mm
(in.)FOR USE WITH
MARKING JOURNAL SIZE
A0.008 mm
U/S64.988±64.995 mm
(0.0004 in.)
U/S(2.5585± 2.5588in.)
BNOMINAL 64.996±65.004 mm
(2.5588±2.5592 in.)
C0.008 mm
O/S65.005±65.012 mm
(0.0004 in.)
O/S(2.5592±2.5595 in.)
INSPECTION
Wipe the inserts clean and inspect for abnormal
wear patterns and for metal or other foreign material
imbedded in the lining. Normal main bearing insert
wear patterns are illustrated (Fig. 9).
NOTE: If any of the crankshaft journals are scored,
the crankshaft must be repaired or replaced.Inspect the back of the inserts for fractures, scrap-
ings or irregular wear patterns.
Inspect the upper insert locking tabs for damage.
Replace all damaged or worn bearing inserts.
CRANKSHAFT OIL SEAL -
FRONT
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(3) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(4) Remove upper radiator hose.
(5) Remove radiator shroud attaching fasteners.
(6) Remove radiator cooling fan and shroud (Refer
to 7 - COOLING/ENGINE/RADIATOR FAN -
REMOVAL).
(7) Remove crankshaft damper bolt.
(8) Remove damper using Special Tools 8513A
Insert and 8454 Three Jaw Puller.
(9) Using Special Tool 9071, remove crankshaft
front seal.
INSTALLATION
CAUTION: The front crankshaft seal must be
installed dry. Do not apply lubricant to sealing lip or
to outer edge.
(1) Using Special Tool 8348 and 8512A, install
crankshaft front seal.
CAUTION: To prevent severe damage to the Crank-
shaft or Damper, thoroughly clean the damper bore
and the crankshaft nose before installing Damper.
(2) Install vibration damper (Refer to 9 - ENGINE/
ENGINE BLOCK/VIBRATION DAMPER - INSTAL-
LATION).
(3) Install radiator cooling fan and shroud (Refer
to 7 - COOLING/ENGINE/RADIATOR FAN -
INSTALLATION).
(4) Install upper radiator hose.
(5) Install accessory drive belt refer (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(6) Refill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(7) Connect negative cable to battery.
Fig. 9 Main Bearing Wear Patterns
1 - UPPER INSERT
2 - NO WEAR IN THIS AREA
3 - LOW AREA IN BEARING LINING
4 - LOWER INSERT
9 - 208 ENGINE - 5.7LDR
CRANKSHAFT MAIN BEARINGS (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)

REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Remove the air cleaner(Refer to 9 - ENGINE/
AIR INTAKE SYSTEM - REMOVAL).
(3) Remove intake manifold(Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - REMOVAL).
(4) Remove cylinder head cover(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(5) Remove rocker arm assembly and push rod-
s(Refer to 9 - ENGINE/CYLINDER HEAD/ROCKER
ARM / ADJUSTER ASSY - REMOVAL). Identify
push rods to ensure installation in original location.
(6) Remove the cylinder head(Refer to 9 -
ENGINE/CYLINDER HEAD - REMOVAL).
(7) Remove bolt from tappet guide holder.
(8) Remove tappet guide holder.
(9) Pull tappet out of bore with a twisting motion.
If all tappets are to be removed and reused, identify
tappets to ensure installation in original location.
(10) Check camshaft lobes for abnormal wear.
INSTALLATION
(1) Lubricate tappets.
(2) Install tappets in their original positions.
(3)
Install tappet guide holder. Install the tappet
guide holder bolt and tighten to 12 N´m (106 in. lbs.)
torque.
(4) Install cylinder head(Refer to 9 - ENGINE/
CYLINDER HEAD - INSTALLATION).
(5) Install pushrods and rocker arm assembly(Re-
fer to 9 - ENGINE/CYLINDER HEAD/ROCKER
ARM / ADJUSTER ASSY - INSTALLATION).
(6) Install cylinder head cover(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(7)
Install intake manifold(Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - INSTALLATION).
(8) Install the air cleaner(Refer to 9 - ENGINE/
AIR INTAKE SYSTEM - INSTALLATION).
(9) Connect the negative cable to the battery.
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.
(10) Road test vehicle and check for leaks.
PISTON & CONNECTING ROD
DESCRIPTION
CAUTION: Do not use a metal stamp to mark con-
necting rods as damage may result, instead use ink
or a scratch awl.The pistons are made of a high strength aluminum
alloy. Piston skirts are coated with a solid lubricant
(Molykote) to reduce friction and provide scuff resis-
tance. The piston top ring groove and land is anod-
ized. The connecting rods are made of forged
powdered metal, with a ªfractured capº design. A
pressed fit piston pin is used to attach the piston and
connecting rod.
STANDARD PROCEDUREÐPISTON FITTING
(1) To correctly select the proper size piston, a cyl-
inder bore gauge, capable of reading in 0.003 mm (
.0001 in.) INCREMENTS is required. If a bore gauge
is not available, do not use an inside micrometer.
(2) Measure the inside diameter of the cylinder
bore at a point 38.0 mm (1.5 inches) below top of
bore. Start perpendicular (across or at 90 degrees) to
the axis of the crankshaft at point A and then take
an additional bore reading 90 degrees to that at point
B (Fig. 11).
(3) The coated pistons will be serviced with the
piston pin and connecting rod pre-assembled. The
piston-rod assembly is specific for the left cylinder
bank ( odd numbered) and the right cylinder bank (
even numbered) and must not be interchanged.
(4) The coating material is applied to the piston
after the final piston machining process. Measuring
the outside diameter of a coated piston will not pro-
vide accurate results (Fig. 10). Therefore measuring
the inside diameter of the cylinder bore with a dial
Bore Gauge isMANDATORY. To correctly select the
proper size piston, a cylinder bore gauge capable of
reading in 0.003 mm (.0001 in.) increments is
required.
Fig. 10 MOLY COATED PISTON
1 - MOLY COATED
2 - MOLY COATED
DRENGINE - 5.7L 9 - 211
HYDRAULIC TAPPETS (Continued)