3.0l v6 - VIN [3] Dodge Caravan I

ENGINE IDENTIFICATION

Note. For engine repair procedures not covered in this article, see ENGINE OVERHAUL PROCEDURES - GENERAL INFORMATION article in the GENERAL INFORMATION section.

Note. Complete specifications for 3.0L engine were not available from manufacturer.

The engine can be identified by the eighth character of the Vehicle Identification Number (VIN). The VIN is located on a metal tag on upper left corner of dashboard and is visible through the windshield.

The engine can also be identified by Engine Identification Number (EIN). The EIN is located on right front side of block, adjacent to exhaust manifold.

VIN ENGINE CODES

Valve Arrangement

1. Right Bank - I-E-I-E-I-E (Front-to-rear).
2. Left Bank - E-I-E-I-E-I (Front-to-rear).

Engine is equipped with hydraulic automatic lash adjusters. No valve adjustment is necessary.

ENGINE REMOVAL

See ENGINE REMOVAL - V6 article in the ENGINES section.

INTAKE MANIFOLD

To release pressure, loosen gas cap to release tank pressure. Remove wiring harness connector from injector. Ground one terminal of injector. Connect a jumper wire to second terminal and energize injector by touching other end of jumper to battery positive terminal for 10 seconds. Remove jumper wires and proceed with fuel system service.

Removal

1. Relieve fuel pressure. Disconnect negative battery cable. Drain cooling system. Remove air cleaner to throttle body hose. Remove throttle cable and transaxle kickdown linkage. Remove Automatic Idle Speed (AIS) motor. Remove Throttle Position Sensor (TPS) wiring from throttle body.
2. Label and disconnect vacuum hose harness from throttle body. Remove EGR tube flange from intake manifold. Label and remove wiring connectors from charge temperature sensor and coolant temperature sensor. Remove vacuum connections from air intake vacuum connector.
3. Remove fuel hoses from fuel rail. Remove upper air intake. (Scheme 35) Cover intake manifold ports when servicing. Remove vacuum lines from fuel rail and fuel pressure regulator.
4. Disconnect fuel injector wiring harness from engine wiring harness. Remove fuel pressure regulator attaching bolts, loosen hose clamps and remove regulator from fuel rail. Remove fuel rail retaining bolts and lift fuel rail assembly from intake manifold. Disconnect radiator and heater hoses. Remove intake manifold. (Scheme 35)

Inspection

Inspect for clogged water passages in end crossovers and clogged exhaust gas passages. For complete cleaning and inspection procedures, see ENGINE OVERHAUL PROCEDURES - GENERAL INFORMATION article.

Installation

1. Clean all gasket mating surfaces. Position intake manifold gasket on cylinder head and install intake manifold. Install 8 retaining nuts with washers and tighten progressively in sequence. (Scheme 36)
2. Make sure that injector holes are clean and all plugs have been removed. Lubricate injector "O" rings with motor oil and install injectors until firmly seated into port. Install fuel rail and retaining bolts.
3. Install fuel pressure regulator and hose assembly onto fuel rail. Install manifold attaching bolts and tighten to specification. Install fuel supply, return tube and vacuum crossover tube hold-down bolts.
4. Tighten fuel pressure regulator hose clamps. Connect fuel injector wiring harness to engine wiring harness. Connect vacuum harness to fuel pressure regulator and fuel rail assembly. Apply sealant to intake manifold gasket and position it with beaded sealant side up on intake manifold.
5. Install upper air intake. Install 8 retaining bolts and tighten in several steps in sequence. (Scheme 37) Connect fuel supply line to fuel rail and tighten hose clamps. Connect vacuum harness to air intake. Connect charge temperature sensor connector to sensors. Connect EGR tube flange to intake manifold.
6. Connect PCV and brake booster supply hose to intake manifold. Connect Automatic Idle Speed (AIS) motor and Throttle Position Sensor (TPS) electrical connectors. Connect vacuum vapor harness to throttle body.
7. Install throttle cable and transaxle kickdown linkage. Install air inlet hose assembly. Install radiator-to-thermostat housing hose and heater hose-to-heater pipe nipple. Refill coolant and oil.

Removal & Installation

1. Remove exhaust crossover pipe. Remove exhaust manifold heat shields to gain access to attaching bolts. Remove manifolds.
2. To install, reverse removal procedure. Use new gaskets when installing.

Scheme 35

Scheme 36

Scheme 37

Scheme 38

1. Drain cooling system and remove air cleaner. Label and disconnect all wiring, hoses, lines and linkages from throttle body, distributor, manifolds and cylinder head.
2. Remove timing belt cover. Mark timing belt running direction. Loosen timing belt tensioner. (Scheme 39) Remove timing belt. Using Camshaft Sprocket Holder (MB990775) hold camshaft sprocket and remove camshaft retaining bolt and camshaft sprocket.
3. Remove valve cover. Install auto lash adjuster retainers. (Scheme 38) Remove distributor adaptor. DO NOT remove camshaft bearing caps bolts from bearing caps. Remove rocker arms, rocker shaft and bearing caps as an assembly. Remove upper intake manifold.
4. Remove camshaft. Mark location of, and remove distributor. Remove exhaust manifolds and cross over pipe. Remove cylinder head bolts in sequence. (Scheme 40) Remove cylinder head.

Scheme 39

Scheme 40

Before cleaning cylinder head, check for cracks, leaks and/or damage.

1. Clean all gasket mating surfaces. Install cylinder head gasket. Do not use gasket sealer on head gasket. Install cylinder head. Tighten cylinder head bolts (clean and lightly oiled) in sequence. (Scheme 40)
2. Lubricate and install camshaft on cylinder head. Install rocker arm shafts, apply sealant to bearing cap mating surfaces at both ends of cylinder head. Install rocker arm shaft assembly making sure that arrows on bearing caps are facing the same direction as arrows on cylinder heads. (Scheme 41)
3. Identify camshaft bearing cap No. 1 and install rocker arm shaft into bearing cap as shown. (Scheme 42) Ensure that machined portion of rocker arm shaft is facing downward.
4. Ensure that bearing caps are properly placed. Camshaft bearing cap No. 2 has an oiling inlet hole from cylinder head. (Scheme 43) To complete installation, reverse removal procedure. Tighten bearing caps to specification in 2 steps in the following order; No. 3, No. 2, No. 1 and then No. 4. See «TORQUE SPECIFICATIONS»(/dodge/caravan/i-1984-1990/remont/mechanical/#30l-v6-vin-3__torque-specifications).

Scheme 41

Scheme 42

Scheme 43

Remove valve cover and gasket. Install auto adjuster retainers. (Scheme 38) Remove distributor adaptor. Loosen, but DO NOT remove bolts from bearing caps. Remove rocker arms, shaft assembly and bearing caps as an assembly.

Inspect rocker arm shafts for excessive wear, runout and/or clogged oil passages. Repair or replace as required.

1. Rocker arm shaft on intake bank has a small diameter oil passage hole to identify it from the exhaust bank rocker arm shaft. Reassemble and install rocker arm shafts into No. 1 camshaft bearing cap.
2. Apply sealant to 4 points of camshaft bearing cap ends. (Scheme 41) Install shaft assembly with arrows on bearing caps facing same direction as arrows on cylinder heads (depending on engine side). Tighten bearing caps to specification in 2 steps in the following order; No. 3, No. 2, No. 1 and then No. 4.
3. Install distributor adaptor with new "O" ring and seal. Lightly coat camshaft oil seal with engine oil and install seal. Install camshaft end seal using End Seal Installer (MB998306). To complete installation, reverse removal procedure.

VALVES & VALVE SPRINGS

Check and record valve spring installed height. Label valves to ensure installation in original locations. With cylinder head removed, compress valve springs using valve spring compressor. Remove valve retainer locks, retainers, valve springs, spring seat, oil seals and valve.

Valve springs should be tested whenever they are removed from cylinder head. Check valve stem tip for pitting and/or depression. Clean and inspect valves. Replace valves if stems are excessively worn. See valve stem diameter in ENGINE SPECIFICATIONS table.

1. If valves or seats are reground, check valve stem height. If valve installed height is not correct, grind valve tip to original height specification.
2. Install valve springs with enamelled end up. Do not over-compress valve springs when reinstalling valves or damage to valve stem seal may occur.

Valve & Valve Spring Installed Height

Before valves or seats are reground, measure installed height of valve and valve spring. Record measured heights for reference on reassembly. During reassembly, install appropriate size spacer between valve spring and cylinder head to restore original installed height.

Valve Stem Oil Seals

Umbrella-type oil seals are used on all valves. If seals are removed for any reason, replace with new seals. When reinstalling valves, do not over compress valve springs or damage to the valve stem oil seal may result.

Valve Guides

No information available for valve guide servicing procedures.

Hydraulic Automatic Lash Adjusters Inspection

1. Do not disassemble automatic lash adjusters. To check for proper operation, insert a small diameter wire through air bleed hole in rocker arm. Lightly push down on auto adjuster check ball.
2. While holding check ball down, move rocker arm up and down to check for free play. If no free-play is present, replace automatic adjuster.

Remove timing belt covers. Drain cooling system. Remove drive belts, fan and pulley from water pump. Remove A/C compressor (if equipped). Remove power steering pump. Remove crankshaft front pulley. Remove vibration damper with damper puller. Remove front cover bolts and front cover/oil pump.

1. Clean all gasket mating surfaces and remove any burrs. Install front cover/oil pump, using new gasket. Tighten front cover and oil pan bolts to specification. Ensure that proper length bolts go into correct holes.
2. Lubricate front cover seal lip. Install vibration damper onto crankshaft. To complete installation, reverse removal procedure. (Scheme 44)and (Scheme 45).

Scheme 44

With accessory drive belts and accessories removed, remove crankshaft pulley and vibration damper. Pry seal out from behind lip, using care not to damage crankshaft seal surface of front cover. To install use front crankshaft oil seal installer tool (MB998306) install oil seal in oil pump.

Remove timing belt cover. Mark timing belt rotation direction. Loosen and/or remove timing belt tensioner. (Scheme 39) Remove timing belt. Remove crankshaft sprocket flange.

Inspect belt for hardening of back rubber. This condition can be identified by a glossy non resilient appearance. Belt will also leave no indent when depressed with fingernail. Check for conditions of cracks, peeling, abnormal wear and/or missing teeth.

1. Install belt tensioner and tensioner spring. Install tensioner spring between water pump retaining pin and tensioner bracket with hook of spring facing outward. Turn tensioner full counterclockwise in adjustment slot and tighten temporarily to hold tensioner in position.
2. Install timing belt on crankshaft sprocket first while keeping belt tight on tension side. (Scheme 39) Install belt on radiator side camshaft sprocket. Then, install belt on water pump pulley and rear camshaft sprocket and finally on timing belt tensioner.
3. Apply rotating force to front camshaft sprocket in opposite direction of tension side of belt. (Scheme 39) Ensure that ALL timing marks are aligned. Install crankshaft sprocket flange. Loosen tensioner from temporary position and allow it to apply tension to timing belt. Turn crankshaft 2 full turns in a clockwise direction ONLY. NOTE: Turn crankshaft smoothly and ONLY in a clockwise direction.
4. Again line up all timing marks and tighten tensioner against belt. Tighten tensioner locking bolt to specification. To complete installation, reverse removal procedures.

1. Remove air cleaner and valve covers. Install auto lash adjuster retainers. Remove distributor adapter. (Scheme 38) Remove rocker arm shafts with bearing caps as an assembly. Remove camshaft.
2. To replace camshaft bearings, remove upper bearing halves from camshaft bearing caps and lower bearing halves from cylinder head.

Ensure all oil passages to camshaft are clear. Inspect camshaft for bearing journal damage and/or binding. Check tooth surface of distributor drive gear for abnormal wear. Measure cam lobe lift. Standard lift is 1.610-1.620" (40.92-41.12 mm). Wear limit is 1.600" (40.42 mm).

1. Lubricate and install camshaft on cylinder head. Install rocker arm shafts, apply sealant to bearing cap ends at both ends of cylinder head. Install rocker arm shaft assembly making sure that arrows on bearing caps are facing the same direction as arrows on cylinder heads. (Scheme 41)
2. Identify camshaft bearing cap No. 1 and install rocker arm shaft into bearing cap as shown. (Scheme 42) Ensure that machined portion of rocker arm shaft is facing downward.
3. Ensure that bearing caps are properly placed. Camshaft bearing cap No. 2 has an oiling inlet hole from cylinder head. (Scheme 43) Install new camshaft oil seal and end seal. To complete installation, reverse removal procedure. Tighten bearing caps to specification in 2 steps in the following order; No. 3, No. 2, No. 1 and then No. 4. See «TORQUE SPECIFICATIONS»(/dodge/caravan/i-1984-1990/remont/mechanical/#30l-v6-vin-3__torque-specifications) table.

OIL PAN

See ENGINE OIL PAN REMOVAL - V6 article in the ENGINES section.

PISTON & ROD ASSEMBLY

1. Measure bore of cylinder to check for excessive wear, excessive taper and/or out-of-round. Top measurement of cylinder bore must be taken .393" (10.00 mm) below top of cylinder bore. Bottom measurement must be taken .393" (10.00 mm) up from bottom of cylinder bore.
2. Standard bore diameter is 3.59" (91.10 mm). Maximum allowable out-of-round is .0008" (0.02 mm). Oversize pistons are available in .010", .020", .030" and .040" (0.25, 0.50, 0.75 and 1.0 mm).
3. Maximum allowable warpage for cylinder block-to-cylinder head mating surface is .003" (0.08 mm). Maximum machining of cylinder block deck surface is .078" (2.0 mm).

1. Clean and inspect pistons and connecting rod assemblies. When installing oil ring side rail do not attempt to use a ring expander. Install piston rings from bottom of piston up.
2. For cylinders No. 1, 3 and 5 install pistons with "R" marking towards the front of engine. For cylinders No. 2, 4 and 6, install pistons with "L" markings towards front of engine.
3. Connecting rods front mark "72" will always face front of engine (timing belt). Connecting rod side clearance is .004-.010" (0.10-0.25 mm). Maximum clearance is .015" (0.4 mm). Maximum allowable connecting rod twist is .0019" (.05 mm).

Fitting Pistons & Rings

1. For piston and piston ring fitting techniques and procedures, see «ENGINE OVERHAUL PROCEDURES - GENERAL INFORMATION»(/dodge/caravan/i-1984-1990/remont/engine/#engine-overhaul-procedures-general-information) article. For measuring specifications, see ENGINE SPECIFICATIONS table at end of this article.
2. No. 1 and No. 2 piston rings have a different cross section. Ensure that piston rings are installed with manufacturers mark and size mark facing up towards top of piston.

Piston Pin Replacement

Manufacturer information regarding piston pin replacement and specifications were not currently available.

CONNECTING ROD BEARINGS

Use Plastigage method for checking bearing clearances. Ensure rod caps are marked for cylinder identification. Check connecting rod bearing and connecting rod side clearance with feeler gauge. Clearance should be to specifications. See ENGINE SPECIFICATIONS table.

MAIN BEARINGS

1. Use Plastigage method for checking bearing clearances. When removing main bearing cap bolts release torque evenly in several steps. Identify lower bearing shells for reassembly reference. Thrust bearing is located on No. 3 main bearing web.
2. Ensure that grooved oil bearings are positioned securely by tabs in the block and are properly aligned. Tighten main bearing bolts in sequence with arrows facing front of block..

Thrust Washer Main Bearing

Engine uses different type thrust washer bearings. One type has positioning tabs, while other type is plain. One SET of tab type bearing are installed in the block and one SET of plain bearings are installed in the No. 3 main bearing cap. Carefully install mono-block main bearing caps with arrows facing front of block.

Crankshaft End Play

Crankshaft end play is controlled by the No. 3 thrust washer bearings. Crankshaft end play is .002-.010" (0.05-0.25 mm).

To remove rear main oil seal housing, remove 5 retaining bolts from housing and remove. Carefully pry oil seal from housing. To install oil seal, use Oil Seal Installer (MD998718). To install housing, reverse removal procedure.

CRANKCASE CAPACITY

Crankcase capacity is 4 qts. (3.8L).

NORMAL OIL PRESSURE

Specifications for oil pressure is not available.

OIL PRESSURE RELIEF VALVE

Valve is not adjustable. Relief valve opening pressure is set between 71-86 psi (5.0-6.0 kg/cm 2 ).

OIL PUMP

See FRONT COVER/OIL PUMP in this article. (Scheme 44)and (Scheme 45).. Oil pump is mounted on timing belt end of the cylinder block, with inner pump rotor indexed and attached to the crankshaft. The oil pump case also retains crankshaft front oil seal.

Inspect oil pump case for damage and/or cracks. Inspect oil relief plunger, ensure it slides smoothly. Check for broken or damaged relief spring. Check clearance according to OIL PUMP SPECIFICATIONS table.

Scheme 45

OIL PUMP SPECIFICATIONS

Remove timing belt. See TIMING BELT removal article. Drain cooling system. Remove mounting bolts. Separate water pump from water inlet pipe and remove.

1. Clean all gaskets and "O" ring surfaces on surfaces of pump body and water inlet tube. Wet and install new "O" ring on water inlet tube. Wet "O" ring with water ONLY.
2. Install a new gasket and pump inlet over water pipe. Press assembly until insertion into pump takes place. Install mounting bolts and tighten to specification. To complete installation, reverse removal procedure.

Note. For further information on cooling system capacities and other cooling system components, see COOLING SYSTEM SPECIFICATIONS article in the ENGINE COOLING section.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

GENERAL ENGINE SPECIFICATIONS

GENERAL ENGINE SPECIFICATIONS

VALVE SPECIFICATIONS

VALVE SPECIFICATIONS

PISTONS, PINS & RINGS SPECIFICATIONS

PISTONS, PINS & RINGS SPECIFICATIONS

CRANKSHAFT MAIN & CONNECTING ROD BEARINGS SPECS

CRANKSHAFT MAIN & CONNECTING ROD BEARINGS SPECS

VALVE SPRINGS SPECIFICATIONS

VALVE SPRINGS SPECIFICATIONS

CAMSHAFT SPECIFICATIONS

CAMSHAFT SPECIFICATIONS (1)

See also:
• ENGINE OVERHAUL PROCEDURES - GENERAL INFORMATION
• ENGINE REMOVAL - V6
• ENGINE OIL PAN REMOVAL - V6
• COOLING SYSTEM SPECIFICATIONS
• TORQUE SPECIFICATIONS
• OIL PUMP SPECIFICATIONS