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(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 50° to 60° for proper seating of rings (Fig. 29).
DR
CLEANING
Thoroughly clean the oil pan and engine block gas-
ket surfaces.
Use compressed air to clean out: † The galley at the oil filter adaptor hole. † The front and rear oil galley holes. † The 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. 30).
Fig.29CYLINDERBORECROSSHATCHPATTERN 1 - CROSSHATCH PATTERN 2 - INTERSECT ANGLE
(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 50° to 60° 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.
Fig.30BOREGAUGE-TYPICAL
1 - FRONT 2 - BORE GAUGE 3 - CYLINDER BORE 4 - 38 MM (1.5 in)
(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 the measurement near the middle of the bore, then repeat the measurement near the bottom of the bore.
DR ENGINE BLOCK (Continued)
ENGINE - 3.7L
9 - 39
(4) Determine taper by subtracting the smaller
diameter from the larger diameter.
(5) Rotate measuring device 90° 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.CRANKSHAFT DESCRIPTION
The crankshaft is constructed of nodular cast iron. The crankshaft is a three throw split pin design with six counterweights for balancing purposes. The crankshaft is supported by four select fit main bear- ings with the number two serving as the thrust washer location. The main journals of the crankshaft are cross drilled to improve rod bearing lubrication. The number six counterweight has provisions for crankshaft position sensor target wheel mounting. The select fit main bearing markings are located on the rear side of the target wheel (Fig. 31). The crank- shaft oil seals are one piece design. The front oil seal is retained in the timing chain cover, and the rear seal is pressed in to a bore formed by the cylinder block and the bedplate assembly.
REMOVAL
NOTE: To remove the crankshaft from the engine, the engine must be removed from the vehicle.
(1) Remove the engine(Refer to 9 - ENGINE -
REMOVAL).
(2) Remove the engine oil pump(Refer to 9 -
ENGINE/LUBRICATION/OIL PUMP - REMOVAL).
CAUTION: DO NOT pry on the oil pan gasket when removing the oil pan, The oil pan gasket is mounted to the cylinder block in three locations and will remain attached to block when removing oil pan. Gasket can not be removed with oil pan.
(3) Remove the bedplate mounting bolts. Note the
location of the two stud bolts for installation.
(4) Remove the connecting rods from the crank-
shaft.
Fig.31CRANKSHAFTANDTARGETRING
1 - CRANKSHAFT 2 - CRANKSHAFT POSITION SENSOR TARGET RING
CAUTION: The bedplate to cylinder block mating surface is a critical sealing surface. Do not pry on or damage this surface in anyway.
NOTE: The bedplate contains the lower main bear- ing halves. Use care when handling bedplate as not to drop or damage bearing halves. Installing main bearing halves in the wrong position will cause severe damage to the crankshaft.
NOTE: The bedplate has pry points cast into it. Use these points only. The pry points are shown below.
(5) Carefully pry on the pry points (Fig. 32) to
loosen the bedplate then remove the bedplate.
CAUTION: When removing the crankshaft, use care not to damage bearing surfaces on the crankshaft.
(6) Remove the crankshaft. (7) Remove the crankshaft tone wheel.
ENGINE - 3.7L
9 - 40
CRANKSHAFT (Continued)DR
Fig.32BEDPLATEPRYPOINTLOCATION
INSPECTION
NOTE: Thoroughly inspect the connecting rod bear- ing bores and main bearing bores for scoring, blue- ing or severe scratches. Further disassembly may be required.
If connecting rod bearing bores show damage, the cylinder heads must be removed to service the piston and rod assemblies. If the bedplate or the cylinder block main bearing bores show damage the engine must be replaced.
(1) If required, remove the main bearing halves
from the cylinder block and bedplate.
(2) Thoroughly clean the bedplate to cylinder block sealing surfaces and main bearing bores. Remove all oil and sealant residue.
(3) Inspect the bedplate main bearing bores for cracks, scoring or severe blueing. If either condition exists the engine must be replaced.
(4) Inspect the crankshaft thrust washers for scor- ing, scratches, wear or blueing. If either condition exist replace the thrust washers.
(5) Inspect the oil pan gasket/windage tray for splits, tears or cracks in the gasket sealing surfaces. Replace gasket as necessary.
DR CRANKSHAFT (Continued) INSTALLATION
CAUTION: Main bearings are select fit. Refer to Crankshaft Main Bearings in this section for proper bearing selections.
CAUTION: When installing crankshaft, use care not to damage bearing surfaces on the crankshaft.
NOTE: Apply sealant to the tone wheel retaining screws prior to installation.
ENGINE - 3.7L
9 - 41
NOTE: Make sure that the bedplate and cylinder block sealing surfaces are clean and free of oil or other contaminants. Contaminants on the sealing surfaces may cause main bearing distortion and/or oil leaks.
(5) Apply a 2.5mm (0.100 inch) bead of Mopart Engine RTV sealant to the cylinder block-to-bedplate mating surface as shown (Fig. 34).
(1) Lubricate upper main bearing halves with
clean engine oil.
(2) Install the crankshaft tone wheel. Torque the
mounting screws to 15 N·m (11 ft. lbs.).
(3) Position crankshaft in cylinder block. (4) Install the thrust washers (Fig. 33).
Fig.34BEDPLATESEALANT
1 - CYLINDER BLOCK 2 - SEALENT 3 - SEALANT
(6) Coat
the crankshaft main bearing journals with clean engine oil and position the bedplate onto the cylinder block.
NOTE: Lubricate the bedplate retaining bolts with clean engine oil prior to installation.
Fig.33CrankshaftThrustWasherInstallation
1 - CRANKSHAFT THRUST WASHER
CAUTION: The bedplate to cylinder block mating surface must be coated with MoparT Engine RTV sealant prior to installation. Failure to do so will cause severe oil leaks.
ENGINE - 3.7L
9 - 42
CRANKSHAFT (Continued)DR
Fig.35BEDPLATETIGHTENINGSEQUENCE
plate contacts the block.
(7) Install the bedplate retaining bolts, making sure to place the stud bolts in the correct location, Torque the bolts in the sequence shown (Fig. 35). † Hand tighten bolts 1D,1G and 1F until the bed- † Tighten bolts 1A–1J to 54 N·m (40 ft. lbs.) † Tighten bolts 1–8 to 7 N·m (5 ft. lbs.) † Turn bolts 1–8 an additional 90°. † Tighten bolts A–E 27 N·m ( 20 ft. lbs.). (8) Measure crankshaft end play.
(9) Install the connecting rods and measure side clearance(Refer to 9 - ENGINE/ENGINE BLOCK/ PISTON & CONNECTING ROD - STANDARD PRO- CEDURE).
(10) Install oil pump(Refer to 9 - ENGINE/LUBRI-
CATION/OIL PUMP - INSTALLATION).
(11) Install the engine(Refer to 9 - ENGINE -
INSTALLATION).
DR
ENGINE - 3.7L
9 - 43
CRANKSHAFT MAIN BEARINGS
STANDARD PROCEDURE
MAIN BEARING FITTING
SELECT FIT IDENTIFICATION
The main bearings are “select fit” to achieve proper oil clearances. For main bearing selection, the crank- shaft position sensor target wheel has grade identifi- cation marks stamped into it (Fig. 36). These marks are read from left to right, corresponding with jour- nal number 1, 2, 3, 4. The crankshaft position sensor target wheel is mounted to the number 6 counter weight on the crankshaft.
Fig.36MARKINGSONTARGETWHEEL
1 - REARMOST CRANKSHAFT COUNTER WEIGHT 2 - TARGET WHEEL 3 - MAIN BEARING SELECT FIT MARKINGS
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.
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.
MAIN BEARING JOURNAL DIAMETER (CRANKSHAFT REMOVED)
Remove the crankshaft from the cylinder block(Re- fer to 9 - ENGINE/ENGINE BLOCK/CRANKSHAFT - REMOVAL).
Clean the oil off the main bearing journal. Determine the maximum diameter of the journal with a micrometer. Measure at two locations 90° 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 (0.002
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.Install the crankshaft into the cylinder block(Refer to 9 - ENGINE/ENGINE BLOCK/CRANKSHAFT - INSPECTION).
Check crankshaft end play.
CRANKSHAFT MAIN BEARING SELECTION
(1) Service main bearings are available in four grades. The chart below identifies the four service grades available.
JOURNAL SIZE SIZE mm (in.)
63.488 - 63.496 mm (2.4995 - 2.4998 in.) 63.496 - 63.500 mm (2.4998 - 2.4999
in.) 63.500 - 63.504 mm (2.4999 - 2.501
in.) 63.504 - 63.512 mm (2.5001 - 2.5004
in.)Bearing size
Size
Application
Crankshaft
MARKING 9R9 Size
9S9 Size
9T9 Size
9U9 Size
Bearing Code
Upper Bearing
.2.443 - 2.447
Use with crankshaft
mm
size 9R9
(.0961 - .0963
in.)
2.439 - 2.443
Use with crankshaft
mm
(0.960 -.o961
in.) 2.435 - 2.439mm
9S, T9
Use with crankshaft
9U9
ENGINE - 3.7L
9 - 44
CRANKSHAFT MAIN BEARINGS (Continued)DR
Crankshaft
MARKING
JOURNAL SIZE SIZE mm (in.)
(.0958 - .0960
in.)
Lower Bearing Main 919 and 949
919
2.441 - 2.447
Use with crankshaft
mm
(.0961 -.0963
in.)
9R, S9
929
2.435 - 2.441
Use with crankshaft
mm
(.0958 - .0962
in.)
9T, U9
Lower Main Bearing 929 and 939
939
2.429 - 2.435
Use with crankshaft
mm
(.0956 - .0958
in.)
9R, S9
949
2.423 - 2.429
Use with crankshaft
mm
(.0953 - .0956
in.)
9T, U9
Bearing Clearances Main 91, 49
Crankshaft 9R9
Crankshaft 9S9
Crankshaft 9T9
Crankshaft 9U9
Main 92, 39
Crankshaft 9R9
Crankshaft 9S9
Crankshaft 9T9
Crankshaft 9U9.004 - .034 mm ( .00015 - .0013 in.)
.004 - .030 mm ( .00015 - .0011 in.)
.006 - .032 mm (.0002 - .0012 in.)
.002 - .032 mm (.00007 -. 0012 in.)
.016 - .046 mm (.0006 - .0018 in.)
.016 - .042 mm (.00062 - .016 in.)
.018 - .044 mm (.0007 - .0017 in.)
.014 - .044 mm (.0005 - .0017 in.)
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) Remove A/C compressor mouning fasteners and
set aside.
(4) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(5) Remove upper radiator hose. (6) Disconnect electrical connector for fan mounted
inside radiator shroud.
(7) Remove radiator shroud attaching fasteners.
NOTE: Transmission cooler line snaps into shroud lower right hand corner.
(8) Remove radiator cooling fan and shroud (Refer - COOLING/ENGINE/RADIATOR FAN -
to REMOVAL).
(9) Remove crankshaft damper bolt. (10) Remove damper using Special Tools 8513
Insert and 1026 Three Jaw Puller (Fig. 37).
Fig.37CrankshaftDamperRemoval
1 - SPECIAL TOOL 8513 INSERT 2 - SPECIAL TOOL 1026
DR CRANKSHAFT OIL SEAL - FRONT (Continued)
(11) Using Special Tool 8511, remove crankshaft
front seal (Fig. 38).
ENGINE - 3.7L
9 - 45
Fig.39CrankshaftFrontSealInstallation
Fig.38CrankshaftFrontSealRemoval
1 - TIMING CHAIN COVER 2 - SPECIAL TOOL 8348
3 - SPECIAL TOOL 85121 - SPECIAL TOOL 8511
INSTALLATION
CAUTION: To prevent severe damage to the Crank- shaft, Damper or Special Tool 8512, thoroughly clean the damper bore and the crankshaft nose before installing Damper.
CRANKSHAFT OIL SEAL - REAR REMOVAL
NOTE: This procedure can be performed in vehicle.
(1) Using Special Tool 8348 and 8512,
install
crankshaft front seal (Fig. 39).
(2) Install vibration damper (Refer to 9 - ENGINE/ ENGINE BLOCK/VIBRATION DAMPER - INSTAL- LATION).
(3) Install radiator cooling fan and shroud (Refer - COOLING/ENGINE/RADIATOR FAN -
to INSTALLATION).
(4) Install upper radiator hose. (5) Install A/C compressor and tighten fasteners to
54 N·m (40 ft. lbs.).
(6) Install accessory drive belt refer (Refer to 7 - COOLING/ACCESSORY DRIVE/DRIVE BELTS - INSTALLATION).
(7) Refill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(8) Connect negative cable to battery.
(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.
ENGINE - 3.7L
9 - 46
CRANKSHAFT OIL SEAL - REAR (Continued)(3) Using Special Tool 8506 (Fig. 40), remove the
crankshaft rear oil seal.
DR
(3) Using Special Tools 8349 Crankshaft Rear Oil Seal Installer and C-4171 Driver Handle (Fig. 42), 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.
Fig.40CrankshaftRearOilSealRemoval
1 - REAR CRANKSHAFT SEAL 2 - SPECIAL TOOL 8506
INSTALLATION
(1) Lubricate the crankshaft flange with engine oil. (2) Position the magnetic seal guide Special Tool 8349–2 (Fig. 41) onto the crankshaft rear face. Then position the crankshaft rear oil seal onto the guide.
Fig.42CrankshaftRearOilSealInstallation
1 - REAR CRANKSHAFT SEAL 2 - SPECIAL TOOL 8349–1 INSTALLER 3 - SPECIAL TOOL C-4171 HANDLE
(4) Install the flexplate. (5) Install the transmission.
Fig.41CrankshaftRearOilSealGuideSpecialTool
8349–2andOil
1 - REAR CRANKSHAFT SEAL 2 - SPECIAL TOOL 8349–2 GUIDE
DR
ENGINE - 3.7L
9 - 47
FLEX PLATE REMOVAL
(1) Remove the transmission. (2) Remove the bolts and flexplate.
INSTALLATION
(1) Position the flexplate onto the crankshaft and
install the bolts hand tight.
(2) Tighten the flexplate retaining bolts to 95 N·m
(70 ft. lbs.) in the sequence shown (Fig. 43).
(3) Install the transmission.
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. The connecting rods are made of forged pow- dered metal, with a “fractured cap” design. A full floating piston pin is used to attach the piston to the connecting rod (Fig. 44).
Fig.43FlexplateTighteningSequence
1 - FLEXPLATE
Fig.44PISTONANDRODASSEMBLY
1 - CONNECTING ROD 2 - PISTON 3 - PISTON PIN 4 - OIL SLINGER SLOT
ENGINE - 3.7L
9 - 48
PISTON & CONNECTING ROD (Continued) STANDARD PROCEDURECONNECTING ROD BEARING FITTING
DR
Inspect the connecting rod bearings for scoring. Check the bearings for normal wear patterns, scor- ing, grooving, fatigue and pitting (Fig. 45). Replace any bearing that shows abnormal wear.
Inspect the connecting rod journals for signs of
scoring, nicks and burrs (Fig. 46).
Fig.46ScoringCausedbyInsufficientLubrication
orDamagedCrankshaftJournal
Fig.47BearingInsertLocation
1 - Connecting Rod 2 - Bearing Insert - A, B less then .50 mm (.0196 in.)
The lower insert must be dry. Place strip of Plasti- gage 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.
Fig.45ConnectingRodBearingInspection
1 - UPPER BEARING HALF 2 - MATING EDGES 3 - GROOVES CAUSED BY ROD BOLTS SCRATCHING JOURNAL DURING INSTALLATION 4 - WEAR PATTERN - ALWAYS GREATER ON UPPER BEARING
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 position in connecting rod. Center bearing insert in connect- ing rod (Fig. 47)
(3) Use piston ring compressor and Guide Pins Special Tool 8507 (Fig. 48) to install the rod and pis- ton assemblies. The oil slinger slots in the rods must face front of the engine. The “F”’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. Center bearing insert in connecting rod (Fig. 47).
DR PISTON & CONNECTING ROD (Continued)
ENGINE - 3.7L
9 - 49
Fig.49MeasuringBearingClearancewith
Plastigage
1 - PLASTIGAGE SCALE 2 - COMPRESSED PLASTIGAGE
Bearing
Mark
.025 US
SIZE
USED WITH
JOURNAL SIZE
.025 mm (.001 in.)
57.883-57.867 mm (2.2788-2.2783 in.)
Std.
STANDARD
57.908-57.892 mm (2.2798-2.2792 in.)
.250 US
.250 mm (.010 in.)
57.658-57.646 mm (2.2700-2.2695 in.)
CAUTION: Connecting Rod Bolts are Torque to Yield Bolts and Must Not Be Reused. Always replace the Rod Bolts whenever they are loosened or removed.
(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 90° turn.
Fig.48PistonandConnectingRod-Installation-
Typical 1 - “F” TOWARD FRONT OF ENGINE 2 - OIL SLINGER SLOT 3 - RING COMPRESSOR 4 - SPECIAL TOOL 8507
(5) Install bearing cap and connecting rod on the journal and tighten bolts to 27 N·m (20 ft. lbs.) plus a 90° turn. DO NOT rotate crankshaft. Plastigage will smear, resulting in inaccurate indication.
(6) Remove the bearing cap and determine amount of bearing-to-journal clearance by measuring the width of compressed Plastigage (Fig. 49). Refer to Engine Specifications for the proper clearance. Plas- tigage should indicate the same clearance across the entire width of the insert. If the clearance varies, it may be caused by either a tapered journal, bent connecting 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
the specification, determin which services bearing set to use the bearing sizes are as follows:
clearance exceeds
ENGINE - 3.7L
9 - 50
PISTON & CONNECTING ROD (Continued)Slide snug-fitting feeler gauge between the con- necting rod and crankshaft journal flange (Fig. 50). Refer to Engine Specifications for the proper clear- ance. Replace the connecting rod if the side clearance is not within specification.
DR
Fig.51DONOTMEASUREMOLYCOATEDPISTON 1 - MOLY COATED 2 - MOLY COATED
Fig.50CheckingConnectingRodSideClearance-
Typical
STANDARD PROCEDURE—PISTON 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. 52).
(3) The coated pistons will be serviced with the
piston pin and connecting rod pre-assembled.
(4) The coating material is applied to the piston after the final piston machining process. Measuring the out- side diameter of a coated piston will not provide accu- rate results (Fig. 51). Therefore measuring the inside diameter of the cylinder bore with a dial Bore Gauge is MANDATORY. To correctly select the proper size pis- ton, a cylinder bore gauge capable of reading in 0.003
mm (.0001 in.) increments is required.(5) Piston installation into
cylinder bore requires slightly more pressure than that required for non-coated pistons. The bonded coating on the piston will give the appearance of a line-to-line fit with the cylinder bore.
the
REMOVAL
(1) Disconnect negative cable from battery. (2) Remove the following components: † Oil pan and gasket/windage tray (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN - REMOVAL).
Fig.52BOREGAUGE-TYPICAL
1 - FRONT 2 - BORE GAUGE 3 - CYLINDER BORE 4 - 38 MM (1.5 in)
† Cylinder head covers (Refer to 9 - ENGINE/ CYLINDER HEAD/CYLINDER HEAD COVER(S) - REMOVAL) and (Refer to 9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD COVER(S) - REMOVAL). † Timing chain cover (Refer to 9 - ENGINE/ VALVE TIMING/TIMING BELT / CHAIN COVER(S) - REMOVAL). † Cylinder head(s) (Refer to 9 - ENGINE/CYLIN- DER HEAD - REMOVAL) and (Refer to 9 - ENGINE/ CYLINDER HEAD - REMOVAL).
ENGINE - 3.7L
9 - 51
GINE BLOCK/CONNECTING ROD BEARINGS - STANDARD PROCEDURE).
Check the connecting rod for signs of twist or bending. 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 position of rings do not change during this operation.
(3) Position bearing onto connecting rod. Ensure that hole in bearing shell aligns with hole in connecting rod. Lubricate bearing surface with clean engine oil.
(4) Install Special Tool 8507 Connecting Rod
Guides into connecting rod bolt threads (Fig. 53).
DR PISTON & CONNECTING ROD (Continued)
(3) If necessary, remove top ridge of cylinder bores with a reliable ridge reamer before removing pistons from cylinder block. Be sure to keep tops of pistons covered during this operation. Pistons and connect- ing rods must be removed from top of cylinder block. When removing piston and connecting rod assemblies from the engine, rotate crankshaft so the each con- necting 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.
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.
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-
Fig.53PISTONANDCONNECTINGROD
INSTALLATION
1 - “F” TOWARD FRONT OF ENGINE 2 - OIL SLINGER SLOT 3 - RING COMPRESSOR 4 - SPECIAL TOOL 8507
ENGINE - 3.7L
9 - 52
PISTON & CONNECTING ROD (Continued)(5) The pistons are marked on the piston pin bore surface with an raised “F” indicating installation position. This mark must be pointing toward the front of engine on both cylinder banks. The connect- ing rod oil slinger slot faces the front of the engine (Fig. 54).
DR
† Timing chain and cover. (Refer to 9 - ENGINE/ VALVE TIMING/TIMING BELT / CHAIN COVER(S) - INSTALLATION). † Cylinder head covers (Refer to 9 - ENGINE/ CYLINDER HEAD/CYLINDER HEAD COVER(S) - INSTALLATION). † Oil pan and gasket/windage tray. (Refer to 9 - INSTALLA-
ENGINE/LUBRICATION/OIL PAN - TION).
(11) Fill crankcase with proper engine oil to cor-
rect level.
(12) Connect negative cable to battery.
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.
Fig.54PISTONANDCONNECTINGROD
ORIENTATION
1 - MAJOR THRUST SIDE OF PISTON 2 - OIL SLINGER SLOT
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. 55). Replace any rings not within specification.
(6) Wipe cylinder bore clean and lubricate with
engine oil.
(7) Rotate crankshaft until connecting rod journal is on the center of cylinder bore. Insert rod and pis- ton into cylinder bore and carefully position connect- ing rod guides over crankshaft journal.
(8) Tap piston down in cylinder bore using a ham- mer handle. While at the same time, guide connect- ing rod into position on rod journal.
CAUTION: Connecting Rod Bolts are Torque to Yield Bolts and Must Not Be Reused. Always replace the Rod Bolts whenever they are loosened or removed.
(9) Lubricate rod bolts and bearing surfaces with engine oil. Install connecting rod cap and bearing. Tighten bolts to 27 N·m (20 ft. lbs.) plus 90°.
(10) Install the following components: † Cylinder head(s). (Refer to 9 - ENGINE/CYLIN-
DER HEAD - INSTALLATION).
Fig.55RingEndGapMeasurement-Typical
1 - FEELER GAUGE
DR PISTON RINGS (Continued)
ENGINE - 3.7L
9 - 53
PISTON RING SIDE CLEARANCE
PISTON RING SPECIFICATION CHART
NOTE: Make sure the piston ring grooves are clean and free of nicks and burrs.
(5) Measure the ring side clearance as shown (Fig. 56)make sure the feeler gauge fits snugly between the ring land and the ring. Replace any ring not within specification.
Fig.56MeasuringPistonRingSideClearance
1 - FEELER GAUGE
(6) Rotate the ring around the piston, the ring
must rotate in the groove with out binding.
Ring Position
Groove
Upper Ring
Clearance .051-.094mm (0.0020- .0037
in.)
Maximum Clearance
0.11mm (0.004 in.)
Intermediate
0.04-0.08mm
0.10mm
Ring
(0.0016-0.0031
(0.004 in.)
Oil Control Ring
(Steel Rails)
in.)
.019-.229mm (.0007-.0090
in.)
Ring Position
Ring Gap
Upper Ring
0.20-0.36mm (0.0079-0.0142
in.)
.25mm
(0.010 in.)
Wear Limit
0.43mm
(0.0017 in.)
Intermediate
0.37-0.63mm
0.74mm
Ring
(0.0146-0.0249
(0.029 in.)
in.)
Oil Control Ring
(Steel Rail)
0.025-0.76mm (0.0099- 0.03
1.55mm (0.061 in.)
in.)
(7) The No. 1 and No. 2 piston rings have a differ- ent cross section. Ensure No. 2 ring is installed with manufacturers I.D. mark (Dot) facing up, towards top of the piston.
NOTE: Piston rings are installed in the following order: † Oil ring expander. † Upper oil ring side rail. † Lower oil ring side rail. † No. 2 Intermediate piston ring. † No. 1 Upper piston ring.
ENGINE - 3.7L
9 - 54
PISTON RINGS (Continued)DR
(8) Install the oil ring expander. (9) Install upper side rail (Fig. 57) by placing one end between the piston ring groove and the expander ring. Hold end firmly and press down the portion to be installed until side rail is in position. Repeat this step for the lower side rail.
(10) Install No. 2 intermediate piston ring using a
piston ring installer (Fig. 58).
(11) Install No. 1 upper piston ring using a piston
ring installer (Fig. 58).
(12) Position piston ring end gaps as shown in (Fig. 59). It is important that expander ring gap is at least 45° from the side rail gaps, but not on the pis- ton pin center or on the thrust direction.
Fig.59PistonRingEndGapPosition
1 - SIDE RAIL UPPER 2 - NO. 1 RING GAP 3 - PISTON PIN 4 - SIDE RAIL LOWER 5 - NO. 2 RING GAP AND SPACER EXPANDER GAP
(3) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(4) Remove radiator upper hose. (5) Remove upper fan shroud. (6) Using Special Tools 6958 Spanner with Adapter loosen fan and viscous assembly from
Pins 8346, water pump (Fig. 60).
(7) Remove fan and viscous assembly.
Fig.57SideRail—Installation
1 - SIDE RAIL END
Fig.58UpperandIntermediateRings—Installation VIBRATION DAMPER REMOVAL
(1) Disconnect negative cable from battery. (2) Remove accessory drive belt
(Refer to 7 - COOLING/ACCESSORY DRIVE/DRIVE BELTS - REMOVAL).
Fig.60FANASSEMBLY-REMOVAL/ASSEMBLY 1 - SPECIAL TOOL 6958 SPANNER WRENCH WITH ADAPTER PINS 8346
2 - FANDR VIBRATION DAMPER (Continued)
ENGINE - 3.7L
9 - 55
(8) Disconnect electrical connector for fan mounted
inside radiator shroud.
threaded rod’s threads with Mopart Nickel Anti- Seize or (Loctite No. 771).
NOTE: Transmission cooler line snaps into shroud lower right hand corner.
(9) Remove crankshaft damper bolt. (10) Remove damper using Special Tools 8513
Insert and 1026 Three Jaw Puller (Fig. 61).
Fig.62PROPERASSEMBLYMETHODFOR
SPECIALTOOL8512–A
1 - BEARING 2 - NUT 3 - THREADED ROD 4 - BEARING HARDENED SURFACE (FACING NUT) 5 - HARDENED WASHER
(3) Using Special Tool 8512–A, press damper onto
crankshaft (Fig. 63).
Fig.61CRANKSHAFTDAMPER-REMOVAL
1 - SPECIAL TOOL 8513 INSERT 2 - SPECIAL TOOL 1026
INSTALLATION
CAUTION: To prevent severe damage to the Crank- shaft, Damper or Special Tool 8512–A, thoroughly clean the damper bore and the crankshaft nose before installing Damper.
(1) Align crankshaft damper slot with key in
crankshaft. Slide damper onto crankshaft slightly.
CAUTION: Special Tool 8512–A, is assembled in a specific sequence. Failure to assemble this tool in this sequence can result in tool failure and severe damage to either the tool or the crankshaft.
(2) Assemble Special Tool 8512–A as follows, The nut is threaded onto the shaft first. Then the roller bearing is placed onto the threaded rod (The hard- ened bearing surface of the bearing MUST face the nut). Then the hardened washer slides onto the threaded rod (Fig. 62). Once assembled coat the
Fig.63CrankshaftDamperInstallation
1 - SPECIAL TOOL 8512
(4) Install then tighten crankshaft damper bolt to
175 N·m (130 ft. lbs.).
ENGINE - 3.7L
9 - 56
VIBRATION DAMPER (Continued)(5) Install fan blade assembly (Refer to 7 - COOL- ING/ENGINE/FAN DRIVE VISCOUS CLUTCH - INSTALLATION).
(6) Install radiator upper shroud and tighten fas-
teners to 11 N·m (95 in. lbs.).
(7) Connect electrical connector for shroud fan. (8) Install radiator upper hose. (9) Install accessory drive belt (Refer to 7 - COOL- ING/ACCESSORY DRIVE/DRIVE BELTS - INSTAL- LATION).
(10) Refill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(11) Connect negative cable to battery.
STRUCTURAL COVER DESCRIPTION
The structural dust cover is made of die cast alu- minum and joins the lower half of the transmission bell housing to the engine bedplate.
OPERATION
The structural cover provides additional power-
train stiffness and reduces noise and vibration.
REMOVAL
(1) Raise vehicle on hoist. (2) Remove the left hand exhaust pipe from
exhaust manifold.
(3) Loosen the right hand exhaust manifold-to-ex-
haust pipe retaining bolts.
(4) Remove the eight bolts retaining structural
cover (Fig. 64) in the sequence shown.
(5) Pivot the exhaust pipe downward and remove
the structural cover.
DR
INSTALLATION
CAUTION: The structural cover must be installed as described in the following steps. Failure to do so will cause severe damage to the cover.
(1) Position the structural cover in the vehicle. (2) Install all four bolts retaining the cover-to-en-
gine. DO NOT tighten the bolts at this time.
(3) Install the four cover-to-transmission bolts. Do
NOT tighten at this time.
CAUTION: The structural cover must be held tightly against both the engine and the transmission bell housing during tightening sequence. Failure to do so may cause damage to the cover.
(4) Starting with the two rear cover-to-engine bolts, tighten bolts (1) (Fig. 65) to 54 N·m (40 ft. lbs.), then tighten bolts (2) (Fig. 65) and (3) to 54 N·m ( 40
ft. lbs.) in the sequence shown.Fig.65StructuralCover
1 - BOLT 2 - BOLT 3 - BOLT
(5) Install the exhaust pipe on left hand exhaust
manifold.
(6) Tighten
exhaust manifold-to-exhaust retaining bolts to 20–26 N·m (15–20 ft. lbs.).
pipe
Fig.64StructuralCover
1 - BOLT 2 - BOLT 3 - BOLT
DR
FRONT MOUNT REMOVAL
2WD
ENGINE - 3.7L
9 - 57
(12) Raise the engine far enough to be able to
remove the left and right engine mounts.
(13) Remove the (8) mount to engine attaching
bolts
(14) Remove the engine mounts.
(1) Disconnect the negative cable from the battery.
4WD
CAUTION: Remove the viscous fan before raising engine. Failure to do so may cause damage to the fan blade, fan clutch and fan shroud.
(2) Remove the viscous fan (Refer to 7 - COOL- ING/ENGINE/FAN DRIVE VISCOUS CLUTCH - REMOVAL).
(3) Raise the vehicle. (4) Remove the engine oil filter. (5) Remove the oil drain trough. (6) Support the engine with a suitable jack and a block of wood across the full width of the engine oil pan.
(7) Support the front axle with a suitable jack. (8) Remove the (4) bolts that attach the engine
mounts to the front axle.
(9) Remove the (3) bolts that attach the front axle
to the left engine bracket.
(10) Lower the front axle. (11) Remove the through bolts
(1) Disconnect the negative cable from the battery.
CAUTION: Remove the viscous fan before raising engine. Failure to do so may cause damage to the fan blade, fan clutch and fan shroud.
(2) Remove the viscous fan (Refer to 7 - COOL- ING/ENGINE/FAN DRIVE VISCOUS CLUTCH - REMOVAL).
(3) Raise the vehicle. (4) Remove the skid plate. (5) Remove the front crossmember. (6) Remove the engine oil filter. (7) Remove the oil drain trough. (8) Support the engine with a suitable jack and a block of wood across the full width of the engine oil pan.
(9) Support the front axle with a suitable jack. (10) Remove the (4) bolts that attach the engine
mounts to the front axle (Fig. 66).
Fig.66ENGINEINSULATORMOUNTS4X4
1 - RH INSULATOR TO AXLE BOLT 2 - NUT 3 - PINION SUPPORT MOUNT 4 - LH INSULATOR MOUNT
5 - LH INSULATOR TO AXLE BOLT 6 - FRONT AXLE 7 - NUT 8 - RH INSULATOR MOUNT
ENGINE - 3.7L
9 - 58
FRONT MOUNT (Continued)DR
(11) Remove the (3) bolts that attach the front axle
to the left engine bracket.
(12) Lower the front axle. (13) Remove the (6) through bolts (14) Raise the engine far enough to be able to remove the left (Fig. 67) and right (Fig. 68) engine mounts.
Fig.68ENGINEMOUNTSUPPORTBRACKETRH 1 - BOLT 2 - ENGINE MOUNT SUPPORT BRACKET
(4) Tighten the through bolt nuts to 94 N·m (70 ft.
lbs.).
(5) Install the oil drain trough. (6) Install the engine oil filter. (7) Lower the vehicle. (8) Install the viscous fan (Refer to 7 - COOLING/ ENGINE/FAN DRIVE VISCOUS CLUTCH - REMOVAL).
(9) Reconnect the negative battery cable.
4WD
NOTE: For mount to engine block and left engine bracket to front axle bolts, apply MoparT Lock and Seal Adhesive, Medium Strength Threadlocker.
(1) Install the right and left side engine mounts to
the front axle. Torque nuts to 94 N·m (70 ft. lbs.).
(2) Raise the front axle into the frame and install the left and right side through bolts. Torque nuts to 94 N·m (70 ft. lbs.).
(3) Insert the two upper through bolts into the right and left side engine mounts and loose assemble the two nuts onto the through bolts.
(4) Lower the engine until the left and right side engine brackets rest on the through bolts, and the
Fig.67ENGINEMOUNTSUPPORTBRACKET
1 - BOLT 2 - ENGINE MOUNT SUPPORT BRACKET 3 - BOLT
(15) Remove the engine mounts.
INSTALLATION
2WD
NOTE: For mount to engine block and left engine bracket to front axle bolts, apply MoparT Lock and Seal Adhesive, Medium Strength Threadlocker.
(1) Install the right and left side engine mounts to the engine block with (8) bolts. Torque bolts to 54
N·m (40 ft. lbs.).(2) Insert the (2) through bolts into the right and left side engine mounts and loose assemble the two nuts onto the through bolts.
(3) Lower the engine until the through bolts rest
onto the slots in the frame brackets.
DR FRONT MOUNT (Continued)
ENGINE - 3.7L
9 - 59
Fig.69ENGINEINSULATORMOUNTS4X4
1 - RH INSULATOR TO AXLE BOLT 2 - NUT 3 - PINION SUPPORT MOUNT 4 - LH INSULATOR MOUNT
5 - LH INSULATOR TO AXLE BOLT 6 - FRONT AXLE 7 - NUT 8 - RH INSULATOR MOUNT
lower engine bracket through holes align with the engine mounts, and the left engine bracket holes align with the front axle slots (Fig. 69).
(5) Loose assemble the (3) bolts that attach the
front axle to the left engine bracket.
(6) Loose assemble the lower through bolts. (7) Torque the nuts for the (4) through bolts to 101
N·m (75 ft. lbs.).
(8) Torque the (3) bolts that attach the front axle
to the left engine bracket to 101 N·m (75 ft. lbs.).
(9) Install the oil drain trough. (10) Install the engine oil filter. (11) Install the front crossmember. (12) Install the skid plate. (13) Lower the vehicle. (14) Install the viscous fan (Refer to 7 - COOL- ING/ENGINE/FAN DRIVE VISCOUS CLUTCH - REMOVAL).
(15) Reconnect the negative battery cable.
9 - 60
ENGINE - 3.7L
REAR MOUNT REMOVAL
(1) Raise the vehicle on a hoist. (2) Using a suitable jack, support transmission. (3) Remove the nuts from the transmission mount
(Fig. 70).
Fig.70TRANSMISSIONMOUNT
1 - MOUNT 2 - CROSSMEMBER 3 - NUT 4 - BOLT
(4) Remove the two bolts that attach the transmis-
sion mount to the engine bracket.
(5) Raise the transmission enough to remove the
mount from the crossmember.
(6) Remove the mount.
INSTALLATION
NOTE: Threadlocking compound must be applied to the bolts before installation.
DR
(1) Install the two bolts that attach the transmis-
sion mount to the transmission bracket.
(2) Torque the bolts to 61N·m (45 ft.lbs.) torque. (3) Lower the transmission so the transmission mount rests on the crossmember, and the studs of the transmission mount are aligned in the slots in the crossmember.
(4) Install the nuts onto the transmission mount
studs through the crossmember access slot. (5) Torque the nuts to 54N·m (40 ft. lbs.).
LUBRICATION DESCRIPTION
The lubrication system is a full flow filtration pres-
sure feed type.
OPERATION
Oil from the oil pan is pumped by a gerotor type oil pump directly mounted to the crankshaft nose. Oil pressure is controlled by a relief valve mounted inside the oil pump housing. For lubrication flow refer to (Fig. 71)
The camshaft exhaust valve lobes and rocker arms are lubricated through a small hole in the rocker arm; oil flows through the lash adjuster then through the rocker arm and onto the camshaft lobe. Due to the orientation of the rocker arm, the camshaft intake lobes are not lubed in the same manner as the exhaust lobes. The intake lobes are lubed through internal passages in the camshaft. Oil flows through a bore in the number 3 camshaft bearing bore, and as the camshaft turns, a hole in the camshaft aligns with the hole in the camshaft bore allowing engine oil to enter the camshaft tube. The oil then exits through 1.6mm (0.063 in.) holes drilled into the intake lobes, lubricating the lobes and the rocker arms.
DR LUBRICATION (Continued)
ENGINE - 3.7L
9 - 61
ENGINE LUBRICATION FLOW CHART - BLOCK: TABLE 1
FROM
TO
Oil Pickup Tube Oil Pump Oil Filter Block Main Oil Gallery
Crankshaft Main Journals Crankshaft Number One Main Journal
Left Cylinder Head
Right Cylinder Head
Oil Pump Oil Filter Block Main Oil Gallery 1. Crankshaft Main Journal 2. Left Cylinder Head* 3. Right Cylinder Head* 4. Counterbalance Shaft Rear Journal Crankshaft Rod Journals 1. Front Timing Chain Idler Shaft 2. Counterbalance Shaft - Front Journal 3. Both Secondary Chain Tensioners Refer to Engine Lubrication Flow Chart - Cylinder Heads: Table 2
Refer to Engine Lubrication Flow Chart - Cylinder Heads: Table 2* The cylinder head gaskets have an oil restricter to control oil flow to the cylinder heads
ENGINE LUBRICATION FLOW CHART - CYLINDER HEADS: TABLE 2
FROM
Cylinder Head Oil Port (in bolt hole) Main Oil Gallery (drilled through head from rear to front)
TO
Diagonal Cross Drilling to Main Oil Gallery 1. Base of Camshaft Towers
2. Lash Adjuster Towers Vertical Drilling Through Tower to Camshaft Bearings** Base of Camshaft Towers Lash Adjuster Towers Diagonal Drillings to Hydraulic Lash Adjuster Pockets ** The number three camshaft bearing journal feeds oil into the hollow camshaft tubes. Oil is routed to the intake lobes, which have oil passages drilled into them to lubricate the rocker arms.
ENGINE - 3.7L
9 - 62
LUBRICATION (Continued)DR
Fig.71LUBRICATIONOILFLOW
1 - OIL FLOW TO RIGHT CYLINDER HEAD 2 - CYLINDER BLOCK MAIN OIL GALLERY 3 - LEFT CYLINDER HEAD OIL GALLERY 4 - OIL FLOW TO BOTH SECONDARY TENSIONERS 5 - OIL FLOW TO LEFT CYLINDER HEAD 6 - OIL PRESSURE SENSOR LOCATION
7 - OIL FLOW TO COUNTER BALANCE SHAFT 8 - OIL PUMP OUTLET TO CYLINDER BLOCK 9 - OIL PUMP 10 - OIL FLOW TO CRANKSHAFT MAIN JOURNALS 11 - CRANKSHAFT MAIN BEARING JOURNALS 12 - RIGHT CYLINDER HEAD OIL GALLERY
DR LUBRICATION (Continued) DIAGNOSIS AND TESTING
Begin with a thorough visual
DIAGNOSIS AND TESTING—ENGINE OIL LEAK inspection of the engine, particularly at the area of the suspected leak. If an oil leak source is not readily identifiable, the following steps should be followed:
(1) Do not clean or degrease the engine at this time because some solvents may cause rubber to swell, temporarily stopping the leak.
(2) Add an oil soluble dye (use as recommended by manufacturer). Start the engine and let idle for approximately 15 minutes. Check the oil dipstick to make sure the dye is thoroughly mixed as indicated with a bright yellow color under a black light.
(3) Using a black light, inspect the entire engine for fluorescent dye, particularly at the suspected area of oil leak. If the oil leak is found and identified, repair per service manual instructions.
(4) If dye is not observed, drive the vehicle at var- ious speeds for approximately 24 km (15 miles), and repeat inspection. If the oil leak source is not pos- itively identified at this time, proceed with the air leak detection test method.
Air Leak Detection Test Method
(1) Disconnect the breather cap to air cleaner hose at the breather cap end. Cap or plug breather cap nipple.
(2) Remove the PCV valve from the cylinder head
cover. Cap or plug the PCV valve grommet.
(3) Attach an air hose with pressure gauge and
regulator to the dipstick tube.
CAUTION: Do not subject the engine assembly to more than 20.6 kPa (3 PSI) of test pressure.
(4) Gradually apply air pressure from 1 psi to 2.5
psi maximum while applying soapy water at the sus- pected source. Adjust the regulator to the suitable test pressure that provide the best bubbles which will pinpoint the leak source. If the oil leak is detected and identified, repair per service manual procedures.(5) If the leakage occurs at the rear oil seal area, refer to the section, Inspection for Rear Seal Area Leak.
(6) If no leaks are detected, turn off the air supply and remove the air hose and all plugs and caps. Install the PCV valve and breather cap hose.
ENGINE - 3.7L
9 - 63
(7) Clean the oil off the suspect oil leak area using a suitable solvent. Drive the vehicle at various speeds approximately 24 km (15 miles). Inspect the engine for signs of an oil leak by using a black light.
INSPECTION FOR 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, distributor seal, camshaft bore cup plugs oil galley pipe plugs, oil filter runoff, and main bearing cap to cylinder block mating surfaces. (4) If no leaks are detected, pressurize the crank- case as outlined in the, 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 and scratches. The crankshaft seal flange is especially 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.
ENGINE - 3.7L
9 - 64
LUBRICATION (Continued) DIAGNOSIS AND TESTING - CHECKING ENGINE OIL PRESSURE(1) Remove oil pressure sending unit (Fig. 72)and
install gauge assembly C-3292.
Fig.72OILPRESSURESENDINGUNIT-TYPICAL 1 - BELT 2 - OIL PRESSURE SENSOR 3 - OIL FILTER 4 - ELEC. CONNECTOR
(2) Run engine until thermostat opens. (3) Oil Pressure: † Curb Idle–25 kPa (4 psi) minimum † 3000 rpm–170 - 758 kPa (25 - 110 psi) (4) If oil pressure is 0 at idle, shut off engine. Check for a clogged oil pick-up screen or a pressure relief valve stuck open.
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
DR
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 OIL SEAL - REAR - REMOVAL).
BLOCK/CRANKSHAFT
DR
OIL PAN DESCRIPTION
The engine oil pan is made of laminated steel and has a single plane sealing surface. The sandwich style oil pan gasket has an integrated windage tray and steel carrier (Fig. 73). The sealing area of the gasket is molded with rubber and is designed to be reused as long as the gasket is not cut, torn or ripped.
Fig.73OilPanAndGasket
1 - OIL PAN 2 - WINDAGE TRAY AND INTEGRATED OIL PAN GASKET
REMOVAL
(1) Disconnect the negative battery cable. (2) Install engine support fixture special tool #
8534. Do not raise engine at this time.
(3) Loosen both left and right side engine mount
through bolts. Do not remove bolts.
(4) Remove the structural dust cover, if equipped. (5) Drain engine oil. (6) Remove the front crossmember(Refer to 13 - FRAME & BUMPERS/FRAME/FRONT CROSS- MEMBER - REMOVAL).
CAUTION: Only raise the engine enough to provide clearance for oil pan removal. Check for proper
ENGINE - 3.7L
9 - 65
clearance at fan shroud to fan and cowl to intake manifold.
(7) Raise engine using special tool # 8534 to pro-
vide clearance to remove oil pan.
NOTE: Do not pry on oil pan or oil pan gasket. Gas- ket is integral to engine windage tray and does not come out with oil pan.
(8) Remove the oil pan mounting bolts and oil pan. (9) Unbolt oil pump pickup tube and remove tube. (10) Inspect the integral windage tray (Fig. 74)
and gasket and replace as needed.
Fig.74OilPanAndGasket
1 - OIL PAN 2 - WINDAGE TRAY AND INTEGRATED OIL PAN GASKET
CLEANING
(1) Clean oil pan in solvent and wipe dry with a
clean cloth.
(2) Clean the oil pan gasket surface. DO NOT use a grinder wheel or other abrasive tool to clean seal- ing surface.
(3) Clean oil screen and tube thoroughly in clean
solvent.
9 - 66
ENGINE - 3.7L OIL PAN (Continued) INSPECTIONDR
(1) Inspect oil drain plug and plug hole for
stripped or damaged threads. Repair as necessary.
(2) Inspect the oil pan mounting flange for bends
or distortion. Straighten flange, if necessary.
INSTALLATION
(1) Clean the oil pan gasket mating surface of the
bedplate and oil pan.
(2) Inspect integrated oil pan gasket, and replace
(3) Position the integrated oil pan gasket/windage
as necessary.
tray assembly.
(4) Install the oil pickup tube (5) Install the mounting bolt and nuts. Tighten
nuts to 28 N·m (20 ft. lbs.).
(6) Position the oil pan and install the mounting bolts. Tighten the mounting bolts to 15 N·m (11 ft. lbs.) in the sequence shown (Fig. 75).
(7) Lower the engine into mounts using special
tool # 8534.
(8) Install both the left and right side engine mount through bolts. Tighten the nuts to 68 N·m (50
ft. lbs.).(9) Remove special tool # 8534. (10) Install structural dust cover, if equipped. (11) Install the front crossmember(Refer to 13 - FRAME & BUMPERS/FRAME/FRONT CROSS- MEMBER - INSTALLATION).
(12) Fill engine oil. (13) Reconnect the negative battery cable. (14) Start engine and check for leaks.
OIL PRESSURE SENSOR/ SWITCH DESCRIPTION
The 3–wire, solid-state engine oil pressure sensor (sending unit) is located in an engine oil pressure gallery.
OPERATION
The oil pressure sensor uses three circuits. They
are:
Fig.75OilPanMountingBoltSequence
† A 5–volt power supply from the Powertrain Con- trol Module (PCM) † A sensor ground through the PCM’s sensor return† A signal to the PCM relating to engine oil pres- sure The oil pressure sensor has a 3–wire electrical function very much like the Manifold Absolute Pres- sure (MAP) sensor. Meaning different pressures relate to different output voltages.
A 5–volt supply is sent to the sensor from the PCM to power up the sensor. The sensor returns a voltage signal back to the PCM relating to engine oil pres- sure. This signal is then transferred (bussed) to the instrument panel on either a CCD or PCI bus circuit (depending on vehicle line) to operate the oil pressure gauge and the check gauges lamp. Ground for the sensor is provided by the PCM through a low-noise sensor return.
DR OIL PRESSURE SENSOR/SWITCH (Continued) REMOVAL
DISASSEMBLY
ENGINE - 3.7L
9 - 67
(1) Disconnect the negative cable from the battery. (2) Raise vehicle on hoist. (3) Remove front splash shield. (4) Disconnect oil pressure sender wire (Fig. 76). (5) Remove the pressure sender (Fig. 76).
Fig.76OILPRESSURESENDINGUNIT
1 - BELT 2 - OIL PRESSURE SENSOR 3 - OIL FILTER 4 - ELEC. CONNECTOR
INSTALLATION
(1) Install oil pressure sender. (2) Connect oil pressure sender wire. (3) Install front splash shield. (4) Lower vehicle. (5) Connect the negative battery cable.
OIL PUMP REMOVAL
(1) Remove the oil pan and pick-up tube (Refer to 9 - ENGINE/LUBRICATION/OIL PAN - REMOVAL). (2) Remove the timing chain cover (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT / CHAIN COVER(S) - REMOVAL).
(3) Remove the timing chains and tensioners (Refer to 9 - ENGINE/VALVE TIMING/TIMING BELT/CHAIN AND SPROCKETS - REMOVAL).
(4) Remove the four bolts, primary timing chain
tensioner and the oil pump.
(1) Remove oil pump cover screws and lift off cover
plate.
(2) Remove pump inner and outer rotors.
NOTE: Once the oil pressure relief valve, cup plug, and pin are removed, the pump assembly must be replaced.
(3) If it is necessary to remove the pressure relief valve, drive the roll pin from pump housing and remove cup plug, spring and valve.
INSPECTION
CAUTION: Oil pump pressure relief valve and spring should not be removed from the oil pump. If these are disassembled and or removed from the pump the entire oil pump assem- bly must be replaced.
components
(1) Clean all parts thoroughly. Mating surface of the oil pump housing should be smooth. If the pump cover is scratched or grooved the oil pump assembly should be replaced.
(2) Lay a straight edge across the pump cover sur- face (Fig. 77). If a 0.025 mm (0.001 in.) feeler gauge can be inserted between the cover and the straight edge the oil pump assembly should be replaced.
(3) Measure the thickness of the outer rotor (Fig. 78). If the outer rotor thickness measures at 12.005
mm (0.472 in.) or less the oil pump assembly must be replaced.(4) Measure the diameter of the outer rotor. If the outer rotor diameter measures at 85.925 mm (3.382
in.) or less the oil pump assembly must be replaced. (5) Measure the thickness of the inner rotor (Fig. 79). If the inner rotor thickness measures at 12.005
mm (0.472 in.) or less then the oil pump assembly must be replaced.(6) Slide outer rotor into the body of the oil pump. Press the outer rotor to one side of the oil pump body
