4.0L Engine: Removal & Installation Jeep Wrangler II

REMOVAL & INSTALLATION

Note. For reassembly reference, label all electrical connectors, vacuum hoses and fuel lines before removal. Also place mating marks on engine hood and other major assemblies before removal.

Removal (Cherokee & Grand Cherokee)

1. Remove hood. Disconnect battery cables. Remove battery. Remove air cleaner. Unplug vacuum hose fittings at intake manifold. Drain cooling system. Remove radiator hoses and radiator support. Disconnect harness from electric fan motor (if equipped). Remove fan shroud and fan. Disconnect transmission cooler lines (if equipped). Remove radiator.
2. Discharge A/C system (if equipped) using approved refrigerant recovery/recycling equipment. Remove A/C service valves. Cap compressor ports. Remove A/C condenser. Disconnect heater hoses at water pump and thermostat housing. Disconnect cruise control (if equipped) and throttle linkage. Disconnect distributor wiring, oil pressure sender wire and fuel injection wire harness at each injector. Tag connectors for installation reference.
3. Disconnect line pressure cable to A/T (if equipped). Release fuel pressure. See «FUEL PRESSURE RELEASE»(ref-98248-S21262049292001051800000) . Disconnect fuel supply quick-connect fittings at fuel rail. Remove fuel line bracket from intake manifold. Remove check valve from power brake booster. Disconnect power steering hoses at steering gear (if equipped). Drain power steering pump reservoir. Cap power steering hoses and fittings.
4. Tag and disconnect any remaining vacuum hoses and electrical connectors as required. Raise and support vehicle. Disconnect exhaust pipe from exhaust manifold. Remove starter and flywheel cover. Disconnect oxygen sensor. Disconnect engine speed sensor.
5. On A/T models, mark converter and flexplate for installation reference. Remove converter-to-flexplate bolts. Remove upper and loosen lower bellhousing bolts. Remove engine mount bracket bolts. Lower vehicle.
6. Attach lifting device to engine. Lift engine from front supports. Place support under bellhousing. Remove remaining bellhousing bolts. Remove engine.

Removal (Wrangler)

1. Pad windshield frame using cloth. Raise hood, and rest it against windshield frame. Remove air cleaner resonator and ducts. Drain cooling system. Disconnect battery cables. Remove battery. Discharge A/C system (if equipped) using approved refrigerant recovery/recycling equipment. Disconnect A/C compressor hose. Disconnect wiring from generator, ignition coil, distributor, oil pressure sending unit and fuel injection wiring harness. Disconnect wires at starter solenoid and injector harness connector.
2. Relieve fuel pressure. Disconnect fuel line quick-connect couplings at fuel rail. Remove fuel line bracket from intake manifold. Remove engine ground strap. Disconnect vacuum purge hose from vapor canister "T". Unplug idle speed actuator connector. Disconnect throttle cable and remove from bracket.
3. Disconnect throttle rod at bellcrank. Disconnect cruise control cable (if equipped). Unplug oxygen sensor connector. Disconnect coolant hoses at radiator, intake manifold and thermostat housing. Remove fan shroud and radiator. Remove fan and spacer. Install a 5/16 x 1/2" bolt through fan pulley into water pump flange to maintain pulley and water pump alignment.
4. Remove check valve from power brake booster. Disconnect power steering hoses at steering gear (if equipped). Drain power steering pump reservoir. Cap power steering hoses and fittings.
5. Tag and disconnect any remaining hoses or electrical connectors. Raise and support vehicle. Disconnect exhaust pipe from exhaust manifold. Remove starter. Remove flywheel housing access cover. Remove engine mount through-bolts. Remove upper bellhousing bolts. Loosen lower bellhousing bolts.
6. Lower vehicle. Attach lifting device to engine. Raise engine from front supports. Place support under bellhousing. Remove remaining bellhousing bolts. Lift engine from engine compartment.

Installation (All Models)

1. Remove engine mount cushions from brackets to aid alignment of engine and transmission. Replace fuel line quick-connect "O" rings, spacers and retainers.
2. DO NOT damage trigger wheel on flywheel when installing engine into vehicle with automatic transmission. To complete installation, reverse removal procedure. Adjust throttle and cruise control linkage. See «THROTTLE CABLE ADJUSTMENT»(ref-98248-S08811876582001051800000) under ADJUSTMENTS. Bleed power steering system. See «POWER STEERING BLEEDING»(ref-98248-S01687774562001051800000) . Tighten bolts to specification. See «TORQUE SPECIFICATIONS»(ref-98248-S14074319682001051800000) . Check fluid levels, and refill if necessary.

Removal

1. Disconnect negative battery cable. Remove air inlet from throttle plate assembly. Remove air cleaner. Disconnect throttle and cruise control (if equipped) cables. Disconnect line pressure cable to A/T (if equipped).
2. Unplug all electrical connectors from intake manifold. Release fuel system pressure. See «FUEL PRESSURE RELEASE»(ref-98248-S21262049292001051800000) . Disconnect fuel line quick-connect fittings at fuel rail. Loosen accessory drive belt and tensioner.
3. Remove power steering pump and bracket. Wire pump aside. Remove fuel rail retaining bolts. Remove fuel rail and injector assembly. Raise and support vehicle. Disconnect exhaust pipe from exhaust manifold. Lower vehicle. Remove retaining bolts. Remove intake and exhaust manifolds as an assembly.

Installation

1. Ensure all gasket surfaces are clean. Install NEW gasket. Install exhaust manifold and tighten bolt No. 3 finger tight. Install intake manifold and remaining bolts loosely. Replace fuel line quick-connect "O" rings, spacers and retainers.
2. Tighten bolts in proper sequence to specification. (Scheme 13) See «TORQUE SPECIFICATIONS»(ref-98248-S14074319682001051800000). Reverse removal procedure to complete installation.

Scheme 13

Remove exhaust manifold with intake manifold. See INTAKE MANIFOLD .

1. Disconnect negative battery cable. Drain cooling system. Remove air cleaner and fuel pipe. Remove molded hoses from cylinder head cover. Remove cylinder head cover.
2. Remove rocker arms, bridges, pivots and push rods. See «ROCKER ARMS»(ref-98248-S25135699992001051800000) . Tag all parts for reassembly reference. Loosen serpentine drive belt at power steering pump (if equipped) or at idler pulley. Remove generator bracket-to-cylinder head bolt. Disconnect power steering pump bracket. DO NOT disconnect hoses. Wire power steering pump aside.
3. Remove manifolds. See «INTAKE MANIFOLD»(ref-98248-S22146717362001051800000) and «EXHAUST MANIFOLD»(ref-98248-S18356123142001051800000) . Remove A/C compressor bracket bolts (if equipped) from cylinder head. Loosen through bolt at bottom of A/C compressor bracket. Remove A/C compressor, and wire aside.
4. Tag and disconnect spark plug wires. Remove spark plugs. Disconnect temperature sending unit. Remove ignition coil and bracket assembly.
5. Remove cylinder head bolts. Pull bolt No. 14 out as far as possible and hold in position using tape. Bolt No. 14 cannot be removed until head is moved forward. Remove cylinder head. To exclude debris and contamination, place clean lint-free shop towels into cylinder bores.

1. Clean carbon from combustion chambers and tops of pistons. Ensure all gasket surfaces, head bolts and head bolt holes are clean. Install NEW cylinder head gasket with numbers or word "TOP" upward. DO NOT apply gasket sealant to cylinder head gasket. Ensure all holes are aligned. Install cylinder head bolt No. 14, and hold in raised position using tape. Cylinder head bolt No. 14 cannot be installed after head is in position on block. Install cylinder head.
2. Apply sealant to threads of cylinder head bolt No. 11 before installation. Install cylinder head bolts. Tighten all bolts to specification in 3 stages and in sequence. During final tightening stage, bolt No. 11 requires less torque than the others. (Scheme 14) See «TORQUE SPECIFICATIONS»(ref-98248-S14074319682001051800000).
3. To install remaining components, reverse removal procedure. Install all valve train components into original locations. Adjust A/T linkage. Refill and bleed cooling system. See «COOLING SYSTEM BLEEDING»(ref-98248-S37233517202001051800000). Start engine, and check for leaks.

Scheme 14

Disconnect negative battery cable. Remove drive belts, fan shroud, fan and hub assembly. Remove accessory drive pulley. Remove vibration damper retaining bolt and washer. Using Puller (7697), remove vibration damper and key. Remove front cover oil seal.

1. Position seal on Seal Installer (6139), with open end of seal facing toward cover. Apply thin coat of RTV sealant on outside diameter of seal. Lightly coat crankshaft with engine oil.
2. Position installer over end of crankshaft. Insert draw screw into end of crankshaft. Tighten draw screw nut until seal is fully seated in front cover. Remove installer. Check seal for proper installation. To complete installation, reverse removal procedure.

1. Disconnect negative battery cable. Remove drive belts, fan shroud, fan and hub assembly. Remove accessory drive pulley. Remove vibration damper retaining bolt and washer.
2. Using Puller (7697), remove vibration damper and key. Remove generator bracket assembly and A/C compressor bracket (if equipped). Remove oil pan-to-front cover bolts. Remove front cover-to-block bolts. Carefully remove front cover, ensuring tension spring and thrust pin do not fall out of camshaft preload bolt into oil pan.
3. Remove tension spring and thrust pin from preload bolt. Rotate crankshaft until timing marks on sprockets are aligned. (Scheme 15) Remove preload bolt. Remove timing chain and sprockets as an assembly.

1. Install timing chain and sprockets as an assembly. Ensure timing marks align. Apply sealant to crankshaft keyway and install into crankshaft. Lubricate tension spring, thrust pin and thrust pin bore with MOPAR Engine Oil Supplement (4318002) before installation. Install camshaft sprocket bolt and washer. Tighten to specification. See «TORQUE SPECIFICATIONS»(ref-98248-S14074319682001051800000).
2. Verify proper installation by rotating crankshaft 2 revolutions. Camshaft and crankshaft timing marks should be aligned. (Scheme 15)
3. Install NEW front cover oil seal. Cut oil pan gasket tabs even with face of cylinder block. Remove tabs. Remove gasket from oil pan. Remove crankshaft oil seal from front cover. Clean front cover, oil pan and cylinder block gasket surfaces. Install front cover. To install remaining components, reverse removal procedure. See «TORQUE SPECIFICATIONS»(ref-98248-S14074319682001051800000).

Scheme 15

Note. All reused camshaft/valve train components must be reinstalled in original locations.

Remove valve cover. Alternately loosen rocker arm cap screws (one turn at a time) to prevent damaging bridges. Remove bridges, pivots, rocker arms and push rods. Tag all parts for installation reference.

1. Install all reused components into original locations. Ensure bottom ends of push rods are centered in valve lifters. Lubricate pivot contact area of rocker arms with MOPAR Engine Oil Supplement (4318002). Install cap screws loosely, and then tighten alternately (one turn at a time) to specification. See «TORQUE SPECIFICATIONS»(ref-98248-S14074319682001051800000) .
2. Reverse removal procedure to complete installation. Pour remaining engine oil supplement over entire valve train. Supplement must remain in engine oil for at least 1000 miles. Refill cooling system. Adjust ignition timing. Check for leaks.

1. Disconnect negative battery cable. Drain cooling system. Remove radiator and A/C condenser (if equipped), but DO NOT discharge system. Mark distributor and engine block for installation reference. Remove distributor and ignition wiring. Remove cylinder head. See «CYLINDER HEAD»(ref-98248-S41788492922001051800000) .
2. Remove valve lifters using Hydraulic Valve Lifter Remover/Installer (C-4129-A). Tag each valve lifter for installation reference. Remove timing chain and sprockets. See «TIMING CHAIN & SPROCKETS»(ref-98248-S26247877862001051800000) . Remove front bumper and/or grille as required. Remove camshaft.

1. Lubricate camshaft and dip valve lifters into MOPAR Engine Oil Supplement (4318002). Install camshaft. Reverse removal procedure to complete installation.
2. Pour remaining engine oil supplement over entire valve train. Supplement must remain in engine oil for at least 1000 miles. Refill cooling system. Adjust ignition timing. Check for leaks.

Remove transmission inspection cover. Remove oil pan. See OIL PAN . Remove main bearing cap brace. Remove rear main bearing cap, and push upper seal from groove. Ensure crankshaft and seal groove are not damaged. Remove lower half of seal from bearing cap.

1. Clean surface of crankshaft. Apply thin coat of oil to crankshaft and seal lip. Position upper seal into groove in cylinder block so lip of seal faces front of engine. Place lower half into bearing cap.
2. Coat both ends of lower seal end tabs with sealant. DO NOT apply sealant to lip of seal. Coat outer curved surface of lower seal with soap. Coat lip of seal with engine oil. Position lower seal into bearing cap recess and seat firmly. Coat both chamfered edges of rear main bearing cap with sealant. DO NOT apply sealant to mating surfaces of bearing cap or cylinder block.
3. Install rear main cap in original position. Tighten bolts in 3 stages to specification. See «CRANKSHAFT & MAIN BEARINGS»(ref-98248-S07324612342001051800000) under CYLINDER BLOCK ASSEMBLY under OVERHAUL. To install remaining components, reverse removal procedure.

Note. A counterclockwise rotation water pump is used. Letter "R" is stamped on back of pump impeller. Previous engines may have used a forward rotating pump. Ensure correct pump is used for replacement.

Disconnect negative battery cable. Drain cooling system. Loosen, but do not remove, water pump pulley mounting nuts. Remove accessory drive belt. Remove power steering pump. Remove fan shroud. Remove fan assembly. Disconnect heater hoses and lower radiator hose at water pump. Remove water pump retaining bolts. Remove water pump. Note that one bolt is longer than the others.

1. Clean all gasket surfaces. Install water pump. Tighten bolts to specification. See «TORQUE SPECIFICATIONS»(ref-98248-S14074319682001051800000) . Ensure pump turns freely. Ensure belt is installed correctly to prevent water pump turning in wrong direction. See appropriate article in ENGINE COOLING.
2. To complete installation, reverse removal procedure. Fill with coolant and purge air from cooling system. See «COOLING SYSTEM BLEEDING»(ref-98248-S37233517202001051800000) . Remove coolant temperature sensor to bleed air from system while filling.

1. Disconnect negative battery cable. Raise and support vehicle at side sills. Drain engine oil. Disconnect exhaust pipe at exhaust manifold. Disconnect exhaust hanger at catalytic converter. Lower exhaust pipe. Remove starter. Remove flywheel access cover. Disconnect oil sensor (if equiped).
2. Position jackstand and a wood block directly under vibration damper. Remove through-bolts from engine mounts. Raise engine enough to remove oil pan. Remove transmission cooler line supports from oil pan, if equipped. Remove oil pan retaining bolts. Remove oil pan by sliding it to rear.

1. Ensure all gasket surfaces are clean. Fabricate 4 alignment dowels from 1/4"-20 x 1 1/2" bolts. Cut heads off bolts and cut slot in end of bolts to allow removal with screwdriver. Install 2 dowels in timing cover, and 2 dowels in block. Slide gasket over dowels into position against block and timing cover.
2. Install oil pan with enough bolts to hold pan in place. Remove alignment dowels. Install remaining oil pan bolts and tighten to specification. See «TORQUE SPECIFICATIONS»(ref-98248-S14074319682001051800000) . To complete installation, reverse removal procedure. Fill crankcase. Start engine. Check for leaks.

Do not waste reusable coolant. If the solution is clean, drain the coolant into a clean container for reuse.

Scheme 16

Scheme 17

Scheme 18

Scheme 19

Scheme 20

1. Disconnect the negative battery cable at battery.
2. Drain coolant from radiator.
3. Do not attempt to remove fan/viscous fan drive assembly from vehicle at this time.
4. Remove the front grill.
5. Remove two radiator mounting bolts (Scheme 19)
6. Disconnect both transmission cooler lines from radiator.
7. Disconnect electric fan connector, then disconnect connector harness from shroud (Scheme 19)
8. Disconnect the radiator upper and lower hoses (Scheme 19)
9. Disconnect the overflow hose from radiator (Scheme 19)
10. Remove the air inlet duct at the grill.
11. The lower part of radiator is equipped with two alignment dowel pins (Scheme 20) They are located on the bottom of radiator tank and fit into rubber grommets. These rubber grommets are pressed into the radiator lower crossmember. WARNING: THE AIR CONDITIONING SYSTEM (IF EQUIPPED) IS UNDER A CONSTANT PRESSURE EVEN WITH THE ENGINE OFF. REFER TO REFRIGERANT WARNINGS IN HEATING AND AIR CONDITIONING BEFORE HANDLING ANY AIR CONDITIONING COMPONENT.
12. If equipped with an auxiliary automatic transmission oil cooler, use caution when removing radiator. The oil cooler lines are routed through a rubber air seal on the right side of radiator. Do not cut or tear this seal.
13. Gently lift up and remove radiator from vehicle. Be careful not to scrape the radiator fins against any other component. Also be careful not to disturb the air conditioning condenser (if equipped).

1. Equipped with air conditioning: Gently lower the radiator into the vehicle. Guide the two radiator alignment dowels through the holes in the rubber air seals first and then through the A/C support brackets (Scheme 20) Continue to guide the alignment dowels into the rubber grommets located in lower radiator crossmember. The holes in the L-shaped brackets (located on bottom of A/C condenser) must be positioned between bottom of rubber air seals and top of rubber grommets.
2. Connect the radiator upper and lower hoses and hose clamps to radiator (Scheme 19) CAUTION: The tangs on the hose clamps must be positioned straight down.
3. Install coolant reserve/overflow tank hose at radiator (Scheme 19)
4. Connect both transmission cooler lines at the radiator (Scheme 19)
5. Install both radiator mounting bolts (Scheme 19)
6. Install air inlet duct at grill.
7. Attach electric fan harness to shroud, then connect harness to connector (Scheme 19)
8. Install the grill.
9. Install the fan/viscous fan drive assembly to the water pump.
10. Rotate the fan blades (by hand) and check for interference at fan shroud.
11. Be sure of at least 25 mm (1.0 inch) between tips of fan blades and fan shroud.
12. Fill cooling system.
13. Connect battery cable at battery.
14. Start and warm engine. Check for leaks.

Drain engine oil. Remove oil pan. See OIL PAN . Remove mounting bolts and oil pump. DO NOT move oil pick-up pipe in pump body. If oil pick-up pipe is moved, pick-up pipe must be replaced to ensure an airtight seal. To install, install NEW gasket and oil pump. Tighten retaining bolts to specification. See TORQUE SPECIFICATIONS .