
the cylinder in question.The recommended com-
pression pressures are to be used only as a
guide to diagnosing engine problems. An engine
should not be disassembled to determine the
cause of low compression unless some malfunc-
tion is present.
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE
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
BECAUSE SERIOUS BURNS FROM 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 the engine
OFF.
Clean spark plug recesses with compressed air.
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, with 552 kPa (80 psi) rec-
ommended.
Perform the test procedures on each cylinder
according to the tester manufacturer's instructions.
While testing, listen for pressurized air escaping
through the throttle body, tailpipe and oil filler cap
opening. Check for bubbles in the radiator coolant.
All gauge pressure indications should be equal,
with no more than 25% leakage per cylinder.
FOR EXAMPLE:At 552 kPa (80 psi) input pres-
sure, a minimum of 414 kPa (60 psi) should be main-
tained in the cylinder.
STANDARD PROCEDURE - MEASURING
BEARING CLEARANCE USING PLASTIGAGE
Engine crankshaft bearing clearances can be deter-
mined by use of Plastigage or equivalent. The follow-
ing is the recommended procedure for the use of
Plastigage:(1) Remove oil film from surface to be checked.
Plastigage is soluble in oil.
(2) Place a piece of Plastigage across the entire
width of the bearing shell in the cap approximately
6.35 mm (1/4 in.) off center and away from the oil
holes (Fig. 3). (In addition, suspected areas can be
checked by placing the Plastigage in the suspected
area). Torque the bearing cap bolts of the bearing
being checked to the proper specifications.
(3) Remove the bearing cap and compare the
width of the flattened Plastigage with the metric
scale provided on the package. Locate the band clos-
est to the same width. This band shows the amount
of clearance in thousandths of a millimeter. Differ-
ences in readings between the ends indicate the
amount of taper present. Record all readings taken.
Compare clearance measurements to specs found in
engine specifications (Refer to 9 - ENGINE - SPECI-
FICATIONS).Plastigage generally is accompa-
nied by two scales. One scale is in inches, the
other is a metric scale.
NOTE: Plastigage is available in a variety of clear-
ance ranges. Use the most appropriate range for
the specifications you are checking.
(4) Install the proper crankshaft bearings to
achieve the specified bearing clearances. (Refer to 9 -
ENGINE/ENGINE BLOCK/CRANKSHAFT MAIN
BEARINGS - STANDARD PROCEDURE) (Refer to 9
- ENGINE/ENGINE BLOCK/CONNECTING ROD
BEARINGS - STANDARD PROCEDURE)
STANDARD PROCEDURE - FORM-IN-PLACE
GASKETS AND SEALERS
There are numerous places where form-in-place
gaskets are used on the engine. Care must be taken
Fig. 3 Plastigage Placed in Lower ShellÐTypical
1 - PLASTIC GAUGE
RSENGINE 3.3/3.8L9-79
ENGINE 3.3/3.8L (Continued)

DURE) Be careful not to gouge or scratch the alumi-
num head sealing surface.
Clean all engine oil passages.
INSPECTION
(1) Before cleaning, check for leaks, damage and
cracks.
(2) Clean cylinder head and oil passages.
(3) Check cylinder head for flatness (Fig. 17).
(4) Cylinder head must be flat within:
²Standard dimension = less than 0.05 mm (0.002
inch.)
²Service Limit = 0.2 mm (0.008 inch.)
²Grinding Limit = Maximum of 0.2 mm (0.008
inch.) is permitted.
CAUTION: 0.20 mm (0.008 in.) MAX is a combined
total dimension of the stock removal limit from cyl-
inder head and block top surface (Deck) together.
INSTALLATION - CYLINDER HEAD
(1) Clean all sealing surfaces of engine block and
cylinder heads. (Refer to 9 - ENGINE - STANDARD
PROCEDURE)
(2) Position new gasket(s) on engine block (Fig.
18). The left bank gasket is identified with the ªLº
stamped in the exposed area of the gasket located at
front of engine (shown in (Fig. 18)). The right bank
gasket is identified with a ªRº stamped in the
exposed area of the gasket also, but is located at the
rear of the engine.
(3)The cylinder head bolts are torqued using
the torque yield method, they should be exam-
ined BEFORE reuse. If the threads are necked
down, the bolts must be replaced(Fig. 19).
(4) Necking can be checked by holding a scale or
straight edge against the threads. If all the threads
do not contact the scale the bolt should be replaced.(5) Tighten the cylinder head bolts 1±8 in the
sequence shown in (Fig. 20). Using the 4 step torque
turn method, tighten according to the following val-
ues:
²Step 1: Bolts1±8to61N´m(45ft.lbs.)
²Step 2: Bolts1±8to88N´m(65ft.lbs.)
²Step 3: Bolts1±8(again) to 88 N´m (65 ft. lbs.)
²Step 4: Bolts1±8turn an additional 1/4 Turn.
(Do not use a torque wrench for this step.)
NOTE: Bolt torque after 1/4 turn should be over 122
N´m (90 ft. lbs.). If not, replace the bolt.
(6) Inspect push rods and replace worn or bent
rods.
(7) Install the push rods.
(8) Install the rocker arm and shaft assemblies.
(Refer to 9 - ENGINE/CYLINDER HEAD/ROCKER
ARMS - INSTALLATION)
Fig. 17 Checking Cylinder Head FlatnessÐTypical
Fig. 18 Head Gasket Installation
1 - CYLINDER HEAD GASKET
2 - LOCATION IDENTIFICATION (L = LEFT BANK, R = RIGHT
BANK)
Fig. 19 Checking Bolts for Stretching (Necking)
1 - STRETCHED BOLT
2 - THREADS ARE NOT STRAIGHT ON LINE
3 - THREADS ARE STRAIGHT ON LINE
4 - UNSTRETCHED BOLT
9 - 96 ENGINE 3.3/3.8LRS
CYLINDER HEAD (Continued)

TIMING BELT/CHAIN AND SPROCKETS -
REMOVAL)
(3) Remove the hydraulic lifters. (Refer to 9 -
ENGINE/ENGINE BLOCK/HYDRAULIC LIFTERS
(CAM IN BLOCK) - REMOVAL). Identify each tappet
for reinstallation in original location.
(4) Remove camshaft thrust plate (Fig. 45).
(5) Install a long bolt into front of camshaft to
facilitate removal of the camshaft.
(6) Remove the camshaft (Fig. 45), being careful
not to damage cam bearings with the cam lobes.
NOTE: The camshaft bearings are serviced with the
engine block.
INSPECTION
(1) Check the cam lobes and bearing surfaces for
abnormal wear and damage (Fig. 47). Replace cam-
shaft as required.
NOTE: If camshaft is replaced due to lobe wear or
damage, always replace the lifters.
(2) Measure the lobe actual wear (unworn area -
wear zone = actual wear) (Fig. 47) and replace cam-
shaft if out of limit. Standard value is 0.0254 mm
(0.001 in.), wearlimitis 0.254 mm (0.010 in.).
INSTALLATION
(1) Lubricate camshaft lobes and camshaft bearing
journals with engine oil.
(2) Install a long bolt into the camshaft to assist in
the installation of the camshaft.
(3) Carefully install the camshaft in engine block.
(4) Install camshaft thrust plate and bolts (Fig.
45). Tighten to 12 N´m (105 in. lbs.) torque.
(5) Measure camshaft end play. (Refer to 9 -
ENGINE - SPECIFICATIONS) If not within specifi-
cations, replace thrust plate.
(6) Install the timing chain and sprockets. (Refer
to 9 - ENGINE/VALVE TIMING/TIMING BELT/
CHAIN AND SPROCKETS - INSTALLATION)
NOTE: When camshaft is replaced, all of the
hydraulic lifters must be replaced also.
(7) Install the hydraulic lifters (Refer to 9 -
ENGINE/ENGINE BLOCK/HYDRAULIC LIFTERS
(CAM IN BLOCK) - INSTALLATION). Each lifter
Fig. 45 CAMSHAFT AND BEARINGS
1 - CAMSHAFT
2 - THRUST PLATE
3 - BOLT
4 - CAMSHAFT BEARINGS (SERVICED WITH BLOCK)
Fig. 46 CAMSHAFT IDENTIFICATION
1 - CAMSHAFT - 3.3L ENGINE
2 - CAST-IN RING
3 - CAMSHAFT - 3.8L ENGINE
4 - MACHINED CAST-IN RING
Fig. 47 Checking Camshaft for Wear (Typical)
1 - UNWORN AREA
2 - ACTUAL WEAR
3 - BEARING JOURNAL
4 - LOBE
5 - WEAR ZONE
9 - 108 ENGINE 3.3/3.8LRS
CAMSHAFT & BEARINGS (IN BLOCK) (Continued)

(7) Remove timing chain and sprockets. (Refer to 9
- ENGINE/VALVE TIMING/TIMING BELT/CHAIN
AND SPROCKETS - REMOVAL)
(8) Remove crankshaft rear oil seal and retainer.
(Refer to 9 - ENGINE/ENGINE BLOCK/CRANK-
SHAFT OIL SEAL - REAR - REMOVAL)
(9) Rotate the crankshaft until connecting rod cap
is accessible.
(10) Mark connecting rod cap position using a suit-
able marker/scribe tool.
(11) Remove connecting rod bearing cap. Use care
to prevent damage to the crankshaft bearing sur-
faces.
(12) Repeat removal procedure for each connecting
rod cap.
(13) Remove and discard the main bearing cross
bolts and washers (3.8L engine only).
NOTE: Install new cross bolt and washer assembly
(3.8L engine only) upon reassembly.
(14) Remove the main bearing cap bolts
(15) Remove the main bearing caps.
(16) Remove the crankshaft from engine block.
INSPECTION
The crankshaft journals should be checked for
excessive wear, taper and scoring (Fig. 52). Limits of
taper or out of round on any crankshaft journals
should within specitifications. (Refer to 9 - ENGINE -
SPECIFICATIONS) Journal grinding should not
exceed 0.305 mm (0.012 in.) under the standard jour-
nal diameter. DO NOT grind thrust faces of No. 3
main bearing. DO NOT nick crank pin or bearing fil-
lets. After grinding, remove rough edges from crank-
shaft oil holes and clean out all passages.
CAUTION: With the nodular cast iron crankshafts, it
is important that the final paper or cloth polish bein the same direction as normal rotation in the
engine.
INSTALLATION
(1) Lubricate with engine oil and install the crank-
shaft main bearing halves in the engine block.
(2) Position the crankshaft in engine block (Fig.
54).
(3) Perform main bearing fitting procedure. (Refer
to 9 - ENGINE/ENGINE BLOCK/CRANKSHAFT
MAIN BEARINGS - STANDARD PROCEDURE)
(4) Inspect main cap bolts for stretching (Fig. 53).
Replace bolts that are stretched.
NOTE: The main cap bolts should be examined
before reuse. Bolt stretch can be checked by hold-
ing a scale or straight edge against the threads. If
all the threads do not contact the scale the bolt
must be replaced (Fig. 53).
(5) Install the main bearing caps and bolts.
Tighten bolts to 41 N´m (30 ft. lbs.) plus
1¤4turn.
Fig. 51 Checking Crankshaft End PlayÐTypical
Fig. 52 Crankshaft Journal Measurements
Fig. 53 Check for Stretched (Necked) Bolts
1 - STRETCHED BOLT
2 - THREADS ARE NOT STRAIGHT ON LINE
3 - THREADS ARE STRAIGHT ON LINE
4 - UNSTRETCHED BOLT
RSENGINE 3.3/3.8L9 - 111
CRANKSHAFT (Continued)

CRANKSHAFT MAIN
BEARINGS
STANDARD PROCEDURE - MAIN BEARING
FITTING
Bearing caps are not interchangeable and should
be marked at removal to insure correct assembly
(Fig. 56). Upper and lower bearing halves are NOT
interchangeable. Lower main bearing halves of 1, 3
and 4 are interchangeable. Upper main bearing
halves of 1, 3 and 4 are interchangeable.
Upper and lower number 2 bearing halves are
flanged to carry the crankshaft thrust loads and are
NOT interchangeable with any other bearing halves
in the engine (Fig. 57). All bearing cap bolts removed
during service procedures are to be cleaned and
lubricated with engine oil before installation. Bearing
shells are available in standard and the following
undersizes: 0.025 mm (0.001 in.) and 0.254 mm
(0.010 in). Never install an undersize bearing that
will reduce clearance below specifications.
CRANKSHAFT BEARING OIL CLEARANCE
Inspect the crankshaft bearing journals. (Refer to 9
- ENGINE/ENGINE BLOCK/CRANKSHAFT -
INSPECTION)
Engine crankshaft bearing clearances can be deter-
mined by use of Plastigage or the equivalent. The fol-
lowing is the recommended procedures for the use of
Plastigage with the engine in the vehicle or engine
on a repair stand.PLASTIGAGE METHODÐENGINE IN-VEHICLE
NOTE: The total clearance of the main bearings can
only be determined with the engine in the vehicle
by removing the weight of the crankshaft. This can
be accomplished by either of two following meth-
ods:
(1) Preferred method:
²Shim the bearings adjacent to the bearing to be
checked in order to remove the clearance between
upper bearing shell and the crankshaft. This can be
accomplished by placing a minimum of 0.254 mm
(0.010 in.) shim (e. g. cardboard, matchbook cover,
etc.) between the bearing shell and the bearing cap
on the adjacent bearings and tightening bolts to
14±20 N´m (10±15 ft. lbs.).
²When checking #1 main bearing shim #2 main
bearing.
²When checking #2 main bearing shim #1 & #3
main bearing.
²When checking #3 main bearing shim #2 & #4
main bearing.
²When checking #4 main bearing shim #3 main
bearing.
NOTE: Remove all shims before reassembling
engine.
Fig. 56 Main Bearing Cap Identification
Fig. 57 Main Bearing Identification
1 - OIL GROOVES
2 - OIL HOLES
3 - UPPER BEARINGS
4 - LOWER BEARINGS
RSENGINE 3.3/3.8L9 - 113

(2) Alternative Method:
²Support the weight of the crankshaft with a jack
under the counterweight adjacent to the bearing
being checked.
(3) Remove oil film from surface to be checked.
Plastigage is soluble in oil.
(4) Place a piece of Plastigage across the entire
width of the bearing shell in the cap approximately
6.35 mm (1/4 in.) off center and away from the oil
holes (Fig. 58). (In addition, suspected areas can be
checked by placing the Plastigage in the suspected
area). Torque the bearing cap bolts of the bearing
being checked to the proper specifications.
(5) Remove the bearing cap and compare the width
of the flattened Plastigage (Fig. 59) with the scale
provided on the package. Locate the band closest to
the same width. This band shows the amount of
clearance in thousandths. Differences in readings
between the ends indicate the amount of taper
present. Record all readings taken. (Refer to 9 -
ENGINE - SPECIFICATIONS)Plastigage gener-
ally is accompanied by two scales. One scale is
in inches, the other is a metric scale.
NOTE: Plastigage is available in a variety of clear-
ance ranges. Use the most appropriate range for
the specifications you are checking.PLASTIGAGE METHODÐENGINE OUT-OF-VEHICLE
(1) With engine in the inverted position (crank-
shaft up) and mounted on a repair stand, remove
main journal cap.
(2) Remove oil from journal and bearing shell.
(3) Cut Plastigage to same length as width of the
bearing and place it in parallel with the journal axis
(Fig. 58).
(4) Carefully install the main bearing cap and
tighten the bolts to specified torque.
CAUTION: Do not rotate crankshaft or the Plasti-
gage will be smeared.
(5) Carefully remove the bearing cap and measure
the width of the Plastigage at the widest part using
the scale on the Plastigage package (Fig. 59). Refer
to Engine Specifications for proper clearances (Refer
to 9 - ENGINE - SPECIFICATIONS). If the clearance
exceeds the specified limits, replace the main bear-
ing(s) with the appropriate size, and if necessary,
have the crankshaft machined to next undersize.
REMOVAL - CRANKSHAFT MAIN BEARINGS
(1) Remove the oil pan. (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL)
(2) Identify main bearing caps before removal.
(3) Remove bearing caps one at a time. Remove
upper half of bearing by inserting Special Main Bear-
ing Tool C-3059 (Fig. 60) into the oil hole of crank-
shaft.
(4) Slowly rotate crankshaft clockwise, forcing out
upper half of bearing shell.
Fig. 58 Plastigage Placed in Lower
1 - PLASTIGAGE
Fig. 59 Clearance Measurement
Fig. 60 Upper Main Bearing Removing/Installing
With Special Tool C-3059
1 - SPECIAL TOOL C-3059
2 - BEARING
3 - SPECIAL TOOL C-3059
4 - BEARING
9 - 114 ENGINE 3.3/3.8LRS
CRANKSHAFT MAIN BEARINGS (Continued)

OPERATION
The piston and connecting rod is the link between
the combustion force to the crankshaft.
STANDARD PROCEDURES - FITTING
CONNECTING RODS
The bearing caps are not interchangeable or
reversible, and should be marked at removal to
ensure correct reassembly. The bearing shells must
be installed with the tangs inserted into the
machined grooves in the rods and caps. Install cap
with the tangs on the same side as the rod. For con-
necting rod bearing fitting (Refer to 9 - ENGINE/EN-
GINE BLOCK/CONNECTING ROD BEARINGS -
STANDARD PROCEDURE). Fit all connecting rods
on one bank until complete.NOTE: The connecting rod cap bolts should be
examined before reuse. Bolt stretch can be checked
by holding a scale or straight edge against the
threads. If all the threads do not contact the scale
the bolt must be replaced (Fig. 72).
(1) Before installing the nuts the threads should
be oiled with engine oil.
(2) Install nuts finger tight on each bolt then alter-
nately torque each nut to assemble the cap properly.
(3) Tighten the nuts to 54 N´m PLUS 1/4 turn (40
ft. lbs. PLUS 1/4 turn).
(4) Using a feeler gauge, check connecting rod side
clearance (Fig. 73). Refer to Engine Specifications
(Refer to 9 - ENGINE - SPECIFICATIONS).
Fig. 71 Lifter Aligning Yoke and Retainer
1 - YOKE RETAINER
2 - BOLT - YOKE RETAINER
3 - ALIGNING YOKE
4 - HYDRAULIC LIFTER
Fig. 72 Check for Stretched (Necked) Bolts
1 - STRETCHED BOLT
2 - THREADS ARE NOT STRAIGHT ON LINE
3 - THREADS ARE STRAIGHT ON LINE
4 - UNSTRETCHED BOLT
Fig. 73 Checking Connecting Rod Side Clearance
9 - 120 ENGINE 3.3/3.8LRS
PISTON & CONNECTING ROD (Continued)

STANDARD PROCEDURES - FITTING PISTONS
The piston and cylinder wall must be clean and
dry. Piston diameter should be measured 90 degrees
to piston pin at size location shown in (Fig. 74). Cyl-
inder bores should be measured halfway down the
cylinder bore and transverse to the engine crankshaft
center line shown in (Fig. 75). Refer to Engine Spec-
ifications (Refer to 9 - ENGINE - SPECIFICA-
TIONS).Pistons and cylinder bores should be
measured at normal room temperature, 21ÉC
(70ÉF).
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove the cylinder heads. (Refer to 9 -
ENGINE/CYLINDER HEAD - REMOVAL)
(3) Remove the oil pan. (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL)(4) Remove the top ridge of cylinder bores with a
reliable ridge reamer, if necessary, before removing
pistons from cylinder block.Be sure to keep tops
of pistons covered during this operation. Pis-
tons and connecting rods must be removed
from top of cylinder block. When removing pis-
ton and connecting rod assemblies from the
engine, rotate crankshaft so that each connect-
ing rod is centered in cylinder bore.
(5) Inspect connecting rods and connecting rod
caps for cylinder identification. Identify them, if nec-
essary (Fig. 76).
(6) Remove connecting rod cap. Install connecting
rod bolt protectors on connecting rod bolts (Fig. 77).
(7) Remove each piston and connecting rod assem-
bly out of the cylinder bore.
NOTE: Be careful not to nick crankshaft journals.
(8) After removal, install bearing cap on the mat-
ing rod.
Fig. 74 Piston Measurement Locations
1 - 39.8 mm (1.56 in. ) 3.3L ENGINE
2 - 33.0 mm (1.29 in.) 3.8L ENGINE
Fig. 75 Checking Cylinder Bore Size
Fig. 76 Identify Connecting Rod to Cylinder
1 - CYLINDER NUMBER
Fig. 77 Connecting Rod Protectors
1 - COVER ROD BOLTS WITH A SUITABLE COVERING WHEN
REMOVING OR INSTALLING PISTON ASSEMBLY
RSENGINE 3.3/3.8L9 - 121
PISTON & CONNECTING ROD (Continued)