check engine DODGE RAM 1500 1998 2.G Workshop Manual
Page 1336 of 2627
(9) Install the left side secondary chain guide
(Refer to 9 - ENGINE/VALVE TIMING/TIMING
BELT/CHAIN AND SPROCKETS - INSTALLA-
TION).
(10) Install the cylinder head access plug (Fig. 20).
(11) Re-set and Install the left side secondary
chain tensioner (Refer to 9 - ENGINE/VALVE TIM-
ING/TIMING BELT/CHAIN AND SPROCKETS -
INSTALLATION).
(12) Remove Special Tool 8515.
(13) Install the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(14) Install the crankshaft damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
INSTALLATION).
(15) Install the power steering pump.
(16) Install the fan blade assembly and fan shroud
(Refer to 7 - COOLING/ENGINE/FAN DRIVE VIS-
COUS CLUTCH - INSTALLATION).
(17) Install the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(18) Reinstall the master cylinder and booster
assembly. Refer to section 5 brakes.
(19) Install the intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSTALLATION).
(20) Refill the cooling system (Refer to 7 - COOL-
ING - STANDARD PROCEDURE).
(21) Raise the vehicle.
(22) Install the exhaust pipe onto the left exhaust
manifold.
(23) Lower the vehicle.
(24) Connect the negative cable to the battery.
(25) Start the engine and check for leaks.INSTALLATION - RIGHT CYLINDER HEAD
NOTE: The cylinder head bolts are tightened using
a torque plus angle procedure. The bolts must be
examined BEFORE reuse. If the threads are necked
down the bolts should be replaced.
Necking can be checked by holding a straight edge
against the threads. If all the threads do not contact
the scale, the bolt should be replaced (Fig. 21).
CAUTION: When cleaning cylinder head and cylin-
der block surfaces, DO NOT use a metal scraper
because the surfaces could be cut or ground. Use
only a wooden or plastic scraper.
(1) Clean the cylinder head and cylinder block
mating surfaces (Fig. 22).
(2) Position the new cylinder head gasket on the
locating dowels.
CAUTION: When installing cylinder head, use care
not damage the tensioner arm or the guide arm.
(3) Position the cylinder head onto the cylinder
block. Make sure the cylinder head seats fully over
the locating dowels.
NOTE: The four smaller cylinder head mounting
bolts require sealant to be added to them before
installing. Failure to do so may cause leaks.
(4) Lubricate the cylinder head bolt threads with
clean engine oil and install the ten M10 bolts.
(5) Coat the four M8 cylinder head bolts with
MopartLock and Seal Adhesivethen install the
bolts.
NOTE: The cylinder head bolts are tightened using
an angle torque procedure, however, the bolts are
not a torque-to-yield design.
Fig. 20 Cylinder Head Access Plugs
1 - RIGHT CYLINDER HEAD ACCESS PLUG
2 - LEFT CYLINDER HEAD ACCESS PLUG
Fig. 21 Checking Cylinder Head Bolts for Stretching
(Necking)
1 - STRETCHED BOLT
2 - THREADS ARE NOT STRAIGHT ON LINE
3 - THREADS ARE STRAIGHT ON LINE
4 - UNSTRETCHED BOLT
DRENGINE - 4.7L 9 - 113
CYLINDER HEAD (Continued)
Page 1337 of 2627
(6) Tighten the bolts in sequence (Fig. 23) using
the following steps and torque values:
²Step 1: Tighten bolts 1±10, 20 N´m (15 ft. lbs.).
²Step 2: Tighten bolts 1±10, 47 N´m (35 ft. lbs.).
Tighten bolts 11±14, 25 N´m (18 ft. lbs.).
²Step 3: Tighten bolts 1±10, 90 degrees. Tighten
bolts 11±14, 30 N´m (22 ft. lbs.).
(7) Position the secondary chain onto the camshaft
drive gear, making sure one marked chain link is on
either side of the V8 mark on the gear and position
the gear onto the camshaft.
(8) Install the camshaft drive gear retaining bolt.
(9) Install the right side secondary chain guide
(Refer to 9 - ENGINE/VALVE TIMING/TIMING
BELT / CHAIN COVER(S) - INSTALLATION).
(10) Install the right side cylinder head access
plug (Fig. 24).(11) Re-set and install the right side secondary
chain tensioner.
(12) Remove Special Tool 8515.
(13) Install the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(14) Install the crankshaft damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
INSTALLATION).
(15) Install accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(16) Install the fan shroud.
(17) Install the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(18) Install the intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSTALLATION).
(19) Install oil fill housing onto cylinder head.
(20) Refill the cooling system (Refer to 7 - COOL-
ING - STANDARD PROCEDURE).
(21) Raise the vehicle.
(22) Install the exhaust pipe onto the right
exhaust manifold.
(23) Lower the vehicle.
(24) Reconnect battery negitive cable.
(25) Start the engine and check for leaks.
CAMSHAFT(S) - LEFT
DESCRIPTION
The camshafts consist of powdered metal steel
lobes which are sinter-bonded to a steel tube. A steel
post or nose piece is friction-welded to the steel cam-
shaft tube. Five bearing journals are machined into
Fig. 22 Proper Tool Usage for
1 - PLASTIC/WOOD SCRAPER
Fig. 23 Cylinder Head Tightening Sequence
Fig. 24 Cylinder Head Access Plugs
1 - RIGHT CYLINDER HEAD ACCESS PLUG
2 - LEFT CYLINDER HEAD ACCESS PLUG
9 - 114 ENGINE - 4.7LDR
CYLINDER HEAD (Continued)
Page 1347 of 2627
REMOVAL
NOTE: The cylinder heads must be removed in
order to perform this procedure.
(1) Remove rocker arms and lash adjusters(Refer
to 9 - ENGINE/CYLINDER HEAD/ROCKER ARM /
ADJUSTER ASSY - REMOVAL). (Fig. 41).
(2) Remove the camshaft bearing caps and the
camshaft.
NOTE: All six valve springs and valves are removed
in the same manner; this procedure only covers
one valve and valve spring.
(3) Using Special Tool C-3422±B or C-3422±C
Valve Spring Compressor and Special tool 8519
Adapter, compress the valve spring.
NOTE: It may be necessary to tap the top of the
valve spring to loosen the spring retainers locks
enough to be removed.
(4) Remove the two spring retainer lock halves.
NOTE: the valve spring is under tension use care
when releasing the valve spring compressor.
(5) Remove the valve spring compressor.
(6) Remove the spring retainer, and the spring.NOTE: Check for sharp edges on the keeper
grooves. Remove any burrs from the valve stem
before removing the valve from the cylinder head.
(7) Remove the valve from the cylinder head.
NOTE: The valve stem seals are common between
intake and exhaust.
(8) Remove the valve stem seal. Mark the valve for
proper installation.
TESTING VALVE SPRINGS
NOTE: Whenever the valves are removed from the
cylinder head it is recommended that the valve
springs be inspected and tested for reuse.
Inspect the valve springs for physical signs of wear
or damage. Turn table of tool C-647 until surface is
in line with the 40.12 mm (1.579 in.) mark on the
threaded stud and the zero mark on the front. Place
spring over the stud on the table and lift compress-
ing lever to set tone device. Pull on torque wrench
until a Ping is heard. Take reading on torque wrench
at this instant. Multiply this reading by two. This
will give the spring load at test length. Fractional
measurements are indicated on the table for finer
adjustments. Refer to Specifications Section to obtain
specified height and allowable tensions. Replace any
springs that do not meet specifications (Fig. 42).
INSTALLATION
(1) coat the valve stem with clean engine oil and
insert it into the cylinder head.
(2) Install the valve stem seal. make sure the seal
is fully seated and that the garter spring at the top
of the seal is intact.
Fig. 41 Rocker Arm Removal
1 - CAMSHAFT
2 - SPECIAL TOOL 8516
Fig. 42 Testing Valve Springs
1 - SPECIAL TOOL C-647
9 - 124 ENGINE - 4.7LDR
INTAKE/EXHAUST VALVES & SEATS (Continued)
Page 1348 of 2627
(3) Install the spring and the spring retainer (Fig.
43).
(4) Using the valve spring compressor, compress
the spring and install the two valve spring retainer
halves.
(5) Release the valve spring compressor and make
sure the two spring retainer halves and the spring
retainer are fully seated.
(6) lubricate the camshaft journal with clean
engine oil then Position the camshaft (with the
sprocket dowel on the left camshaft at 11 o'clock and
the right camshaft at 12 o'clock), then position the
camshaft bearing caps.
(7) Install the camshaft bearing cap retaining
bolts. Tighten the bolts 9±13 N´m (100 in. lbs.) in
1¤2
turn increments in the sequence shown (Fig. 44).
(8) Position the hydraulic lash adjusters and
rocker arms.
ROCKER ARM / ADJUSTER
ASSEMBLY
DESCRIPTION
The rocker arms are steel stampings with an inte-
gral roller bearing. The rocker arms incorporate a 2.8mm (0.11 inch) oil hole in the lash adjuster socket for
roller and camshaft lubrication.
DIAGNOSIS AND TESTING - HYDRAULIC LASH
ADJUSTER
A tappet-like noise may be produced from several
items. Check the following items.
(1) Engine oil level too high or too low. This may
cause aerated oil to enter the adjusters and cause
them to be spongy.
(2) Insufficient running time after rebuilding cylin-
der head. Low speed running up to 1 hour may be
required.
(3) Turn engine off and let set for a few minutes
before restarting. Repeat this several times after
engine has reached normal operating temperature.
(4) Low oil pressure.
(5) The oil restrictor in cylinder head gasket or the
oil passage to the cylinder head is plugged with
debris.
(6) Air ingested into oil due to broken or cracked
oil pump pick up.
(7) Worn valve guides.
(8) Rocker arm ears contacting valve spring
retainer.
(9) Rocker arm loose, adjuster stuck or at maxi-
mum extension and still leaves lash in the system.
(10) Oil leak or excessive cam bore wear in cylin-
der head.
(11) Faulty lash adjuster.
a. Check lash adjusters for sponginess while
installed in cylinder head and cam on camshaft atFig. 43 Valve Assembly Configuration
1 - VALVE LOCKS (3±BEAD)
2 - RETAINER
3 - VALVE STEM OIL SEAL
4 - INTAKE VALVE
5 - EXHAUST VALVE
6 - VALVE SPRING
Fig. 44 Camshaft Bearing Caps Tightening
Sequence
DRENGINE - 4.7L 9 - 125
INTAKE/EXHAUST VALVES & SEATS (Continued)
Page 1351 of 2627
ENGINE BLOCK
DESCRIPTION
The cylinder block is made of cast iron. The block
is a closed deck design with the left bank forward. To
provide high rigidity and improved NVH an
enhanced compacted graphite bedplate is bolted to
the block. The block design allows coolant flow
between the cylinders bores, and an internal coolant
bypass to a single poppet inlet thermostat is included
in the cast aluminum front cover.
STANDARD PROCEDURE - CYLINDER BORE
HONING
Before honing, stuff plenty of clean shop towels
under the bores and over the crankshaft to keep
abrasive materials from entering the crankshaft
area.
(1) Used carefully, the Cylinder Bore Sizing Hone
C-823, equipped with 220 grit stones, is the best tool
for this job. In addition to deglazing, it will reduce
taper and out-of-round, as well as removing light
scuffing, scoring and scratches. Usually, a few strokes
will clean up a bore and maintain the required lim-
its.
CAUTION: DO NOT use rigid type hones to remove
cylinder wall glaze.
(2) Deglazing of the cylinder walls may be done if
the cylinder bore is straight and round. Use a cylin-
der surfacing hone, Honing Tool C-3501, equipped
with 280 grit stones (C-3501-3810). about 20-60
strokes, depending on the bore condition, will be suf-
ficient to provide a satisfactory surface. Using honing
oil C-3501-3880, or a light honing oil, available from
major oil distributors.
CAUTION: DO NOT use engine or transmission oil,
mineral spirits, or kerosene.
(3) Honing should be done by moving the hone up
and down fast enough to get a crosshatch pattern.
The hone marks should INTERSECT at 50É to 60É
for proper seating of rings (Fig. 48).
(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.
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. 49).
(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. Repeat
Fig. 48 CYLINDER BORE CROSSHATCH PATTERN
1 - CROSSHATCH PATTERN
2 - INTERSECT ANGLE
9 - 128 ENGINE - 4.7LDR
Page 1352 of 2627
the 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.
CONNECTING ROD BEARINGS
STANDARD PROCEDURE - CONNECTING ROD
BEARING FITTING
Inspect the connecting rod bearings for scoring and
bent alignment tabs (Fig. 50). Check the bearings for
normal wear patterns, scoring, grooving, fatigue and
pitting (Fig. 51). Replace any bearing that shows
abnormal wear.
Inspect the connecting rod journals for signs of
scoring, nicks and burrs.Misaligned or bent connecting rods can cause
abnormal wear on pistons, piston rings, cylinder
walls, connecting rod bearings and crankshaft con-
necting rod journals. If wear patterns or damage to
any of these components indicate the probability of a
misaligned connecting rod, inspect it for correct rod
alignment. Replace misaligned, bent or twisted con-
necting rods.
(1) Wipe the oil from the connecting rod journal.
(2) Lubricate the upper bearing insert and install
in connecting rod.
(3) Use piston ring compressor and Guide Pins
Special Tool 8507 (Fig. 52) to install the rod and pis-
ton assemblies. The oil slinger slots in the rods must
face front of the engine. The ªFº's near the piston
wrist pin bore should point to the front of the engine.
(4) Install the lower bearing insert in the bearing
cap. The lower insert must be dry. Place strip of Plas-
tigage across full width of the lower insert at the cen-
ter of bearing cap. Plastigage must not crumble in
use. If brittle, obtain fresh stock.
(5) Install bearing cap and connecting rod on the
journal and tighten bolts to 27 N´m (20 ft. lbs.) plus a
90É turn. DO NOT rotate crankshaft. Plastigage will
smear, resulting in inaccurate indication.
Fig. 49 BORE GAUGE-TYPICAL
1 - FRONT
2 - BORE GAUGE
3 - CYLINDER BORE
4 - 38 MM (1.5 in)
Fig. 50 Locking Tab Inspection
1 - ABNORMAL CONTACT AREA CAUSED BY LOCKING TABS
NOT FULLY SEATED OR BEING BENT
Fig. 51 Scoring Caused by Insufficient Lubrication
or Damaged Crankshaft Journal
DRENGINE - 4.7L 9 - 129
ENGINE BLOCK (Continued)
Page 1353 of 2627
(6)Remove the bearing cap and determine amount of
bearing-to-journal clearance by measuring the width of
compressed Plastigage (Fig. 53). Refer to Engine Speci-
fications for the proper clearance.Plastigage shouldindicate the same clearance across the entire
width of the insert. If the clearance varies, it may
be caused by either a tapered journal, bent con-
necting rod or foreign material trapped between
the insert and cap or rod.
(7) If the correct clearance is indicated, replace-
ment of the bearing inserts is not necessary. Remove
the Plastigage from crankshaft journal and bearing
insert. Proceed with installation.
(8) If bearing-to-journal clearance exceeds the
specification, determin which services bearing set to
use the bearing sizes are as follows:
Bearing
MarkSIZE USED WITH
JOURNAL SIZE
.025 US.025 mm 50.983-50.967 mm
(.001 in.) (2.0073-2.0066 in.)
Std.STANDARD 50.992-51.008 mm
(2.0076-2.0082 in.)
.250 US.250 mm 50.758-50.742 mm
(.010 in.) (1.9984-1.9978 in.)
(9) Repeat the Plastigage measurement to verify
your bearing selection prior to final assembly.
(10) Once you have selected the proper insert,
install the insert and cap. Tighten the connecting rod
bolts to 27 N´m (20 ft. lbs.) plus a 90É turn.
Slide snug-fitting feeler gauge between the con-
necting rod and crankshaft journal flange (Fig. 54).
Refer to Engine Specifications for the proper clear-
ance. Replace the connecting rod if the side clearance
is not within specification.
Fig. 53 Measuring Bearing Clearance with Plastigage
1 - PLASTIGAGE SCALE
2 - COMPRESSED PLASTIGAGE
Fig. 52 Piston and Connecting Rod - Installation
1 - ªFº TOWARD FRONT OF ENGINE
2 - OIL SLINGER SLOT
3 - RING COMPRESSOR
4 - SPECIAL TOOL 8507
Fig. 54 Checking Connecting Rod Side Clearance -
Typical
9 - 130 ENGINE - 4.7LDR
CONNECTING ROD BEARINGS (Continued)
Page 1360 of 2627
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 (Fig. 67), remove the
crankshaft rear oil seal.
Fig. 67 Crankshaft Rear Oil Seal Removal
1 - REAR CRANKSHAFT SEAL
2 - SPECIAL TOOL 8506
DRENGINE - 4.7L 9 - 137
Page 1363 of 2627
tons covered during this operation.Pistons and
connecting rods must be removed from top of cylinder
block. When removing piston and connecting rod
assemblies from the engine, rotate crankshaft so the
each connecting rod is centered in cylinder bore.
CAUTION: DO NOT use a number stamp or a punch
to mark connecting rods or caps, as damage to
connecting rods could occur
NOTE: Connecting rods and bearing caps are not
interchangeable and should be marked before
removing to ensure correct reassembly.
(4) Mark connecting rod and bearing cap positions
using a permanent ink marker or scribe tool (Fig.
73).
CAUTION: Care must be taken not to damage the
fractured rod and cap joint face surfaces, as engine
damage may occur.
(5) Remove connecting rod cap. Install Special Tool
8507 Connecting Rod Guides into the connecting rod
being removed. Remove piston from cylinder bore.
Repeat this procedure for each piston being removed.
CAUTION: Care must be taken not to nick crank-
shaft journals, as engine damage may occur
(6) Immediately after piston and connecting rod
removal, install bearing cap on the mating connect-
ing rod to prevent damage to the fractured cap and
rod surfaces.
(7) Carefully remove piston rings from piston(s),
starting from the top ring down.CLEANING
CAUTION: DO NOT use a wire wheel or other abra-
sive cleaning devise to clean the pistons or con-
necting rods. The pistons have a Moly coating, this
coating must not be damaged.
(1) Using a suitable cleaning solvent clean the pis-
tons in warm water and towel dry.
(2) Use a wood or plastic scraper to clean the ring
land grooves.
CAUTION: DO NOT remove the piston pin from the
piston and connecting rod assembly.
INSPECTION
Check the connecting rod journal for excessive
wear, taper and scoring (Refer to 9 - ENGINE/EN-
GINE BLOCK/CONNECTING ROD BEARINGS -
STANDARD PROCEDURE).
Check the connecting rod for signs of twist or bend-
ing.
Check the piston for taper and elliptical shape
before it is fitted into the cylinder bore (Refer to 9 -
ENGINE/ENGINE BLOCK/PISTON & CONNECT-
ING ROD - STANDARD PROCEDURE).
Check the piston for scoring, or scraping marks in
the piston skirts. Check the ring lands for cracks
and/or deterioration.
INSTALLATION
(1) Before installing piston and connecting rod
assemblies into the bore, install the piston rings.
(2) Immerse the piston head and rings in clean
engine oil. Position a ring compressor over the piston
and rings. Tighten ring compressor.Ensure posi-
tion of rings do not change during this opera-
tion.
(3) Position bearing onto connecting rod. Ensure
that hole in bearing shell aligns with hole in connect-
ing rod. Lubricate bearing surface with clean engine
oil.
Fig. 73 Identify Connecting Rod to Cylinder
PositionÐTypical
9 - 140 ENGINE - 4.7LDR
PISTON & CONNECTING ROD (Continued)
Page 1365 of 2627
PISTON RINGS
STANDARD PROCEDURE - PISTON RING
FITTING
Before reinstalling used rings or installing new
rings, the ring clearances must be checked.
(1) Wipe the cylinder bore clean.
(2) Insert the ring in the cylinder bore.
NOTE: The ring gap measurement must be made
with the ring positioned at least 12mm (0.50 inch.)
from bottom of cylinder bore.
(3) Using a piston, to ensure that the ring is
squared in the cylinder bore, slide the ring downward
into the cylinder.
(4) Using a feeler gauge check the ring end gap
(Fig. 76). Replace any rings not within specification.
PISTON RING SIDE CLEARANCE
NOTE: Make sure the piston ring grooves are clean
and free of nicks and burrs.
(5) Measure the ring side clearance as shown (Fig.
77) make sure the feeler gauge fits snugly between
the ring land and the ring. Replace any ring not
within specification.
(6) Rotate the ring around the piston, the ring
must rotate in the groove with out binding.
PISTON RING SPECIFICATION CHART
Ring Position Groove
ClearanceMaximum
Clearance
Upper Ring .051-.094 mm 0.11 mm
(0.0020-.0037
in.)(0.004 in.)
Intermediate
Ring0.04-0.08 mm 0.10 mm
(0.0016-0.0031
in.)(0.004 in.)
Oil Control Ring .019-.229 mm .25 mm
(Steel Rails) (.0007-.0090
in.)(0.010 in.)
Ring Position Ring Gap Wear Limit
Upper Ring 0.20-0.36 mm 0.43 mm
(0.0079-0.0142
in.)(0.0017 in.)
Intermediate
Ring0.37-0.63 mm 0.74 mm
(0.0146-0.0249
in.)(0.029 in.)
Oil Control Ring 0.025-0.76 mm 1.55 mm
(Steel Rail) (0.0099- 0.03
in.)(0.061 in.)
Fig. 76 Ring End Gap Measurement - Typical
1 - FEELER GAUGE
Fig. 77 Measuring Piston Ring Side Clearance
1 - FEELER GAUGE
9 - 142 ENGINE - 4.7LDR