Engine Mechanical - 3.4l v6 - VIN [X] Chevrolet Lumina I

ENGINE IDENTIFICATION

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

Vehicle Identification Number (VIN)

VIN is stamped on a metal tab, which is attached to top left end of instrument panel, near windshield. If eighth character of VIN is "X", vehicle is factory-equipped with a 3.4L DOHC V6 engine. The tenth character of VIN is the model year.

Partial VIN

A partial VIN (9 characters) is stamped on left side of cylinder block. (Scheme 1) The second character of partial VIN is the model year.

Engine Code

An engine code (3 characters) is stamped on left side of cylinder block. (Scheme 1) Engine code LQ1 identifies 3.4L DOHC V6 engine.

Scheme 1

VALVE CLEARANCE ADJUSTMENT

Engine is equipped with non-adjustable hydraulic valve lifters.

TROUBLE SHOOTING

Note. To trouble shoot engine mechanical components, see appropriate table in TROUBLE SHOOTING article in GENERAL INFORMATION.

GENERAL PRECAUTION

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.

FUEL PRESSURE RELEASE

Disconnect negative battery cable. Loosen fuel tank filler cap. Connect Fuel Pressure Gauge (J-34730-1) to fuel line fitting (wrap shop towel around fitting to absorb leakage). Place gauge bleed hose into container. Open bleed valve to release pressure.

COOLING SYSTEM DRAINING

Remove radiator cap. Open drain valve at bottom of radiator. Open air bleed screw on thermostat housing. Open air bleed screw on heater coolant inlet pipe near master cylinder. Disconnect coolant inlet hose from engine oil cooler at base of oil filter.

COOLING SYSTEM BLEEDING

Close drain valve at bottom of radiator. Reconnect coolant inlet hose to engine oil cooler. Add coolant to radiator until clear coolant (no air bubbles) comes out of air bleed screws. Tighten air bleed screws. Wait 2 minutes. Add coolant to radiator as necessary. Install and tighten radiator cap. Fill coolant recovery reservoir. Run engine. Allow engine to cool. Check and fill coolant recovery reservoir as necessary.

Note. Remove engine (without transaxle) through top.

Removal

1. Release fuel pressure. See «FUEL PRESSURE RELEASE»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__fuel-pressure-release) procedures. Disconnect negative battery cable. Remove air cleaner and duct assembly. Remove hood. Drain cooling system. See «COOLING SYSTEM DRAINING»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__cooling-system-draining) . Remove coolant recovery reservoir.
2. Disconnect heater hoses from engine. Remove engine torque strut and bracket. Remove cooling fans. Disconnect radiator hoses from engine. Disconnect transaxle cooler lines. Remove radiator. Disconnect control cables from throttle body. Disconnect fuel lines. Remove exhaust crossover pipe.
3. Disconnect ground straps from bellhousing. Remove fuel injector cover. Disconnect power steering lines from pump and front cover. Remove serpentine drive belt. Remove A/C compressor upper bolts. Disconnect A/C clutch electrical connector. Raise and support vehicle.
4. Remove right front wheel and splash shield. Remove A/C compressor lower bolts, and position A/C compressor aside with hoses connected. Remove flexplate/flywheel covers. Remove oil filter and starter. Remove front exhaust pipe and catalytic converter. Remove engine mount nuts from frame.
5. Disconnect electrical connections at rear of engine. Remove bolts securing transaxle to engine. Remove torque converter bolts. Disconnect electrical connections at front of engine. Separate right ball joint from control arm. Disconnect outer tie rod from right steering knuckle.
6. Disconnect right drive axle from transaxle and hub. Remove right drive axle. Remove transaxle shield. Support transaxle from below. Remove bolts and nuts securing motor mount bracket to transaxle. Remove support from below transaxle. Lower vehicle. Remove plastic cover from strut tower.
7. Disconnect ECM quick connectors. Disconnect vacuum lines as necessary. Support transaxle from below. Attach engine hoist to top of engine. Remove engine assembly (disconnect electrical connectors from alternator during removal).

Installation

To install, reverse removal procedure. Fill and bleed cooling system. See COOLING SYSTEM BLEEDING . Fill and bleed power steering system. Add fluids as necessary.

Removal & Installation

Remove coolant recovery tank. Rotate belt tensioner clockwise with a wrench, and remove belt. (Scheme 2) Remove bolt and tensioner. To install, reverse removal procedure. Ensure belt is routed correctly.

Scheme 2

1. Disconnect negative battery cable. Drain cooling system. See «COOLING SYSTEM DRAINING»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__cooling-system-draining). Raise and support vehicle. Place drain pan below engine to catch any fluids. Disconnect oil pressure and crank sensor electrical connectors.
2. Remove oil filter. Disconnect inlet and outlet hoses, and position hoses aside. Remove connector, oil cooler and adapter. (Scheme 3)

Clean mating surface of engine block. Coat gasket with engine oil. To install, reverse removal procedure. Tighten connector to specification. See TORQUE SPECIFICATIONS . Fill and bleed cooling system. See COOLING SYSTEM BLEEDING .

Scheme 3

1. Remove coolant recovery tank. Rotate serpentine belt tensioner clockwise with a wrench, and remove belt. (Scheme 2) Remove bolt and tensioner. Raise and support vehicle. Remove right front wheel and engine splash shield.
2. Remove flexplate/flywheel cover. Using Flywheel Holder (J-37096), remove crankshaft damper bolt. (Scheme 4) Remove crankshaft pulley bolts and pulley. Remove heater pipe screws at coolant recovery tank bracket. Install Damper Remover (J-24420-B) onto damper. Rotate puller screw, and remove damper.
3. Pry out old front cover oil seal with large screwdriver. DO NOT damage crankshaft. Inspect crankshaft and front cover for scratches.

1. Lubricate new seal with clean engine oil. Insert seal into front cover with lip facing engine. Drive seal into place using Oil Seal Installer (J-34995). Apply engine oil to seal contact area on damper. Apply Sealant (GM 12345739) to keyway of damper. Place damper into position over key on crankshaft.
2. Push damper onto crankshaft using Damper Installer (J-29113). Install crankshaft pulley. Tighten bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__torque-specifications) . To complete installation, reverse removal procedure.

Scheme 4

INTERMEDIATE SHAFT BELT SPROCKET

Remove timing belt. See TIMING BELT & CAMSHAFT TIMING PROCEDURE. Raise and support vehicle. Remove flexplate/flywheel inspection cover. Install Flexplate/Flywheel Holder (J-37096). Lower vehicle. Remove sprocket bolt and washer. Using Sprocket Puller (J-38616), remove sprocket. (Scheme 5) Pry out oil seal.

1. Lubricate surface of NEW oil seal where it contacts intermediate shaft sprocket. Using Seal Installer (J-38619), install NEW oil seal. Install belt sprocket, ensuring locating tangs on belt sprocket engage mating sockets in chain sprocket. To verify engagement of tangs in slots, measure distance between front face of belt sprocket and front cover. If distance exceeds 1.65" (42 mm), tangs are not engaged.
2. Ensure camshafts are properly aligned. See «TIMING BELT & CAMSHAFT TIMING PROCEDURE»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__timing-belt-camshaft-timing-procedure) . Lightly lubricate shaft seal "O" ring, and place it into end of intermediate shaft. Lightly lubricate sprocket bolt threads and washer (DO NOT over-lubricate). Tighten bolt to specification. Refer to «TORQUE SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__torque-specifications) . To complete installation, reverse removal procedures.

Scheme 5

1. Disconnect negative battery cable. Remove timing belt, tensioner pulley, and idler pulleys. See «TIMING BELT & CAMSHAFT TIMING PROCEDURE»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__timing-belt-camshaft-timing-procedure) . Remove timing belt tensioner bracket. Remove engine front lift bracket. Remove both cooling fans. Disconnect coolant hoses from water pump.
2. Remove heater pipe bracket screws at frame. Raise and support vehicle. Remove starter, crankshaft damper, and alternator. Remove engine oil filter and oil cooler assembly. Remove nuts and bolts from front half of oil pan. Slightly loosen remaining oil pan bolts.
3. Remove A/C compressor (leave hoses attached). Remove lower bolts from front cover. Leave Flexplate/Flywheel Holder (J-37096) in position. Lower vehicle.
4. Using Sprocket Remover (J-38616), remove belt sprocket from intermediate shaft. Remove forward light relay center, and position it aside. Remove water pump pulley. Remove remaining front cover bolts. Remove front cover and gasket.

1. Clean gasket surfaces (DO NOT damage sealing surfaces). Install NEW gasket. Apply Sealer (1052080) to lower edges of front cover sealing surface. Apply Sealer (1052080) to large bolts. (Scheme 6)
2. Install front cover and upper bolts. Tighten bolts just enough to pull front cover against block. Install water pump pulley. Connect oil cooler coolant hose to front cover. Install forward light relay center. Install upper alternator bolts.
3. Install belt sprocket onto intermediate shaft. See «TIMING BELT & CAMSHAFT TIMING PROCEDURE»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__timing-belt-camshaft-timing-procedure). Raise and support vehicle. Install remaining front cover bolts. Tighten all front cover bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__torque-specifications). To complete installation, reverse removal procedure.

Scheme 6

1. Remove front cover. See FRONT COVER. Mark crankshaft and intermediate shaft sprockets in relation to timing chain for reassembly reference. (Scheme 7) Remove timing chain tensioner bolts.
2. Raise and support vehicle. Remove timing chain and crankshaft sprocket using Universal Puller Bridge (J-8433) and Legs/Protector (J-38611). If intermediate gear does not slide off easily with timing chain assembly, rotate crankshaft back and forth to help loosen gear. Remove timing chain tensioner.

Inspection

Inspect crankshaft alignment key for burrs or marks that could affect assembly. Repair or replace as necessary.

1. Ensure crankshaft key is installed and fully seated. Using Tensioner Retractor (J-33875), retract timing chain tensioner shoe and lock it in place with a cotter pin, rivet, or nail. (Scheme 8)
2. Using upper hole as primary locator, install tensioner. Finger-tighten tensioner bolts. Tighten slotted bolt and then remaining bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__torque-specifications). Apply light coat of oil or lithium grease to chain contact surfaces of nylon pad and blade (if equipped).
3. Install chain and sprocket assembly, aligning marks made during removal. During installation, keep assembly aligned (parallel). (Scheme 9) Intermediate shaft may move against rear cover. Ensure rubber and tension blade of tensioner do not become caught, misaligned or dislodged.
4. Large chamfer and counterbore on crankshaft sprocket must face engine. (Scheme 7) Spline sockets on intermediate shaft sprocket must face engine.
5. Crankshaft sprocket must be pressed onto crankshaft for the last.31" (8 mm) using Sprocket Installer (J-38612). Ensure timing is correct. Pull pin from tensioner. To complete installation, reverse removal procedure.

Scheme 7

Scheme 8

Scheme 9

1. Release fuel line pressure. See «FUEL PRESSURE RELEASE»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__fuel-pressure-release) . Remove air cleaner assembly and duct. Drain cooling system. See «COOLING SYSTEM DRAINING»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__cooling-system-draining) . Disconnect control cables at throttle body. Remove fuel rail cover.
2. Disconnect vacuum modulator line from intake manifold. Disconnect fuel lines from fuel rail. Disconnect heater hose from lower intake manifold. Remove PCV valve. Disconnect vacuum line at throttle body. Disconnect electrical connectors for AIR solenoid, EGR valve and TP sensor.
3. Remove EGR valve and position it aside. Remove fuel line bracket at throttle body. Loosen throttle body heater hose clamp at upper intake manifold. Disconnect electrical connectors for canister purge solenoid and MAP sensor. Disconnect vacuum hoses at "T" fitting on upper intake manifold.
4. Remove wiring loom bracket for rear bank of spark plug wires. Remove nuts at upper intake manifold support bracket. Remove bolts, upper intake manifold, and gasket. To complete installation, reverse removal procedure. Use NEW intake manifold gasket. Tighten nuts and bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__torque-specifications) . Fill and bleed cooling system. See «COOLING SYSTEM BLEEDING»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__cooling-system-bleeding) .

1. Remove upper intake manifold. See «INTAKE MANIFOLD (UPPER)»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x) . Disconnect feed and return lines from fuel rail. Plug openings to prevent contamination. Disconnect fuel injector electrical connectors. Disconnect vacuum line from pressure regulator.
2. Remove 4 bolts and fuel rail. Disconnect radiator hose from thermostat housing. Disconnect temperature sensor electrical connector. Remove heater pipe nut at throttle body. Remove bolts, lower intake manifold, and gaskets. If necessary, remove vent hose, bolts, oil distribution cover, and gasket.

1. Clean gasket surfaces. Install gaskets. Position lower intake manifold on engine. Temporarily install and finger-tighten two M8 X 1.25 X 50 mm bolts into vertical bolt holes to keep manifold in place. Tighten these vertical bolts to 62 INCH lbs. (7 N.m). Before tightening any bolts or nuts, install all manifold bolts and insert rubber isolators fully into manifold flange.
2. Draw manifold into place by tightening bolts gradually, starting with middle bolts and working in a circular pattern. Tighten bolts and nuts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__torque-specifications) . Remove 2 vertical bolts. To complete installation, reverse removal procedure. Use NEW "O" rings in fuel system where applicable.

Oil distribution cover is under lower intake manifold. See INTAKE MANIFOLD (LOWER) .

Removal (Left)

Remove air cleaner and duct assembly. Remove exhaust crossover pipe. Remove both cooling fans. Remove nuts, heat shield, exhaust manifold, and gasket. If replacing manifold, transfer old air piping and heat shield to new manifold.

Removal (Right)

1. Remove air cleaner and duct assembly. Remove exhaust crossover pipe. Disconnect EGR tube from exhaust manifold. Raise and support vehicle. Remove or disconnect front exhaust pipe and catalytic converter assembly. Disconnect oxygen sensor electrical connector.
2. Remove exhaust pipe front heat shield. Remove rear alternator brace. Remove transaxle dipstick tube (A/T). Disconnect intermediate steering shaft from steering gear. Remove exhaust manifold nuts. Put an adjustable support under rear crossmember of engine cradle (front suspension frame).
3. Remove bolts securing rear end of engine cradle to body. Lower rear end of engine cradle. Remove steering gear heat shield. Remove heat shield, exhaust manifold, and gasket.

Installation (Left & Right)

To install, reverse removal procedure. Tighten nuts and bolts to specification. See TORQUE SPECIFICATIONS.

Removal (Left Bank)

1. Disconnect breather hose from cover. Disconnect spark plug wires from plugs. Remove spark plug wire cover. Remove bolts and camshaft carrier cover. Remove cover gasket and "O" rings. Remove timing belt. See «TIMING BELT & CAMSHAFT TIMING PROCEDURE»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__timing-belt-camshaft-timing-procedure) .
2. Remove exhaust crossover pipe. Remove engine torque strut from between top of radiator panel and engine. Remove thermostat housing from lower intake manifold. Remove engine lift bracket. To retain lifters in carrier, install 6" long fuel line hose between camshaft and lifters (use 3/16" diameter hose for exhaust side, and 5/32" diameter hose for intake side). Remove bolts, camshaft carrier, and gasket.

Removal (Right Bank)

1. Remove upper intake manifold. See «INTAKE MANIFOLD (UPPER)»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x) . Remove right timing belt cover. Disconnect right spark plug wires. Disconnect breather hose from cover. Remove bolts and camshaft carrier cover. Remove cover gasket and "O" rings. Remove timing belt. See «TIMING BELT & CAMSHAFT TIMING PROCEDURE»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__timing-belt-camshaft-timing-procedure) .
2. To retain lifters in carrier, install 6" long fuel line hose between camshaft and lifters (use 3/16" diameter hose for exhaust side, and 5/32" diameter hose for intake side). Remove bolts, camshaft carrier, and gasket.

Remove oil from camshaft carrier-to-cylinder head bolt holes. Install gasket. Install Camshaft Hold-Down (J-38613). (Scheme 12) Install camshaft carrier. Tighten bolts and nuts to specification. See TORQUE SPECIFICATIONS. Remove lifter retaining hoses and camshaft hold-down. To complete installation, reverse removal procedure and see TIMING BELT & CAMSHAFT TIMING PROCEDURE.

Drain cooling system. See COOLING SYSTEM DRAINING . Remove air cleaner assembly. Disconnect upper radiator hose. Remove exhaust crossover pipe. Remove upper intake manifold. Refer to INTAKE MANIFOLD (UPPER) . Disconnect heater pipe from water pump. Remove engine torque strut from between engine and top of radiator panel. Remove engine lift support. Remove bolts, cover, and gasket from rear end of camshaft carrier.

Remove air cleaner and duct assembly. Release fuel line pressure. See FUEL PRESSURE RELEASE . Disconnect fuel lines. Remove brake master cylinder. Remove bolts, cover, and gasket from rear end of camshaft carrier.

To install, reverse removal procedure. Use NEW gasket. Tighten bolts to specification. See TORQUE SPECIFICATIONS. Fill and bleed cooling system (if servicing end cover on left camshaft carrier). See COOLING SYSTEM BLEEDING .

CAMSHAFT SPROCKETS

Note. For reference, left bank is front bank, and right bank is rear bank.

For removal and installation, see TIMING BELT & CAMSHAFT TIMING PROCEDURE .

CAMSHAFT

Note. Camshaft journals are all the same diameter. Remove camshaft carefully to avoid damaging bearings.

1. Remove timing belt. See «TIMING BELT & CAMSHAFT TIMING PROCEDURE»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__timing-belt-camshaft-timing-procedure). Remove camshaft carrier. See «CAMSHAFT CARRIER & COVERS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x). Remove valve lifters. Remove oil from bolt hole, and install Camshaft Hold-Down (J-38613). (Scheme 12) Tighten hold-down bolt to 22 ft. lbs. (30 N.m).
2. Remove camshaft sprockets. See «TIMING BELT & CAMSHAFT TIMING PROCEDURE»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__timing-belt-camshaft-timing-procedure). Remove bolts and end cover from camshaft carrier. Remove bolt and camshaft thrust plate. Remove camshaft hold-down. Carefully remove camshaft from back of camshaft carrier. Carefully pry out oil seal.

Replace camshaft if it is worn or deformed. Inspect nose of camshaft for brinelling from flat ring. Pressure marks are acceptable. Replace camshaft if grooves are present.

1. Coat oil seal, camshaft lobes and journals with GM Lubricant (1052367). Install oil seal using Seal Installer (J-38619). Carefully install camshaft into camshaft carrier. DO NOT damage or distort oil seal. Install thrust plate. Tighten thrust plate bolt to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__torque-specifications).
2. Install end cover onto camshaft carrier with NEW gasket. Lubricate lifters with GM Lubricant (1052367). Install lifters. Install camshaft carrier. See «CAMSHAFT CARRIER & COVERS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x). Remove oil from bolt hole, and install Camshaft Hold-Down (J-38613). (Scheme 12) Tighten hold-down bolt to 22 ft. lbs. (30 N.m). Install camshaft sprocket. To complete installation and insure proper cam timing, See «TIMING BELT & CAMSHAFT TIMING PROCEDURE»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__timing-belt-camshaft-timing-procedure).

TIMING BELT & CAMSHAFT TIMING PROCEDURE

Note. For reference, left bank is front bank, and right bank is rear bank.

Note. Tools required: Cam Hold Down (J-38613-A), Camshaft Sprocket Holding Tool (J-38614) and Torque Angle Meter (J-36660-A).

Note. The camshaft timing procedure has been updated by TSB bulletin No. 47-61-34, dated December, 1994. Before proceeding, see SECTION 6A9 - REVISED CAMSHAFT TIMING PROCEDURE for possible updated information.

For belt measurement specification, see TIMING BELT TENSION SPECIFICATIONS .

TIMING BELT TENSION SPECIFICATIONS

1. Disconnect negative battery cable. Remove air cleaner duct. Drain engine coolant. See «COOLING SYSTEM DRAINING»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__cooling-system-draining). Disconnect accelerator and cruise control cables from throttle body. Remove the fuel injector sight shield. Remove fuel rail cover and relieve fuel pressure. See «FUEL PRESSURE RELEASE»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__fuel-pressure-release). Remove fuel lines from fuel rail and remove fuel mounting bracket.
2. Remove heater hose and bracket from lower intake manifold. Remove PCV valve and vacuum line from throttle body. Disconnect electrical connector from EGR. Remove EGR valve. Disconnect electrical connection from canister purge solenoid and MAP sensor. Remove vacuum lines from upper intake manifold tee. Remove wiring loom bracket for rear spark plug wires. Disconnect power brake vacuum hose and remove upper intake manifold support bracket and manifold. Remove coolant recovery tank.
3. Remove serpentine belt and belt tensioner. Remove power steering pump. Disconnect PCM electrical connectors and reposition. Disconnect spark plug wires from spark plugs. Relocate wiring harness cover at right strut tower. Remove fuel line bracket and all upper timing belt covers (3). Remove breather hose from rear camshaft cover, and crankcase vent from breather manifold.
4. Remove camshaft carrier covers. See «CAMSHAFT CARRIER & COVERS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x). Remove side plate bolts from actuator and rotate actuator assembly from tensioner pulley socket, and out of mounting base. (Scheme 11) Remove timing belt tensioner pulley. (Scheme 11) DO NOT install the rod tip or the tensioner actuator boot in the jaws of a vise or damage to the assembly may occur.
5. Position actuator in vertical position (rod tip down), lightly clamp actuator body in vise. (Scheme 13) (Position the tensioner actuator up, so the oil goes to the boot end for at least 5 minutes before refilling the actuator prior to reassembly, if necessary). Actuator assembly uses a tapered bushing between actuator and mounting base. DO NOT lose or damage bushing when removing actuator assembly.
6. Straighten out a standard paper clip.032" (.81mm) diameter, to a minimum straight length of 1.85 " (47 mm). Form a double loop in remaining end of paper clip. (Scheme 15) Actuator assembly is filled with oil and removal of the plug may allow oil to escape. DO NOT remove vent plug. Push paper clip through center of vent plug and into pilot hole. Insert a small screwdriver into screw slot inside actuator, behind rubber end plug. Retract actuator plunger by rotating screw in a clockwise direction, until it is fully retracted. Push on paper clip and slowly rotate screw counterclockwise until paper clip engages. This unloads tensioner.
7. Remove timing belt. Rotate crankshaft so No. 1 cylinder is at TDC (Top Dead Center). Mark crankshaft timing indicator (with White paint or equivalent) on crankshaft balancer and front cover only. (Scheme 12)
8. Position camshafts so flat spots are UP for installation of Cam Hold Down. (Scheme 17) Install Cam Hold Downs on both camshaft carriers. One on left (front head) and the other on the right (rear head). To remove camshaft sprockets, install Cam Hold Down and remove bolts, taper lock rings, and sprockets by lightly tapping on it with a soft faced hammer. (Scheme 16)

Note. The camshaft timing procedure has been updated by TSB bulletin No. 47-61-34, dated December, 1994. Before proceeding, see SECTION 6A9 - REVISED CAMSHAFT TIMING PROCEDURE for possible updated information.

Note. Tools required: Cam Hold Down (J-38613-A).

1. Install intermediate drive sprocket and all camshaft sprockets with taper lock rings FINGER TIGHT. Install timing belt in a counterclockwise direction around sprockets. Ensure timing belt teeth are fully engaged with all sprockets. Tighten tensioner pulley bolt to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__torque-specifications).
2. If actuator oil has been lost, fill actuator with SAE 5w30 Mobil 1 (or equivalent) synthetic engine oil through end hole. Fill to bottom of plug hole, only when actuator is fully retracted, and pin is installed. Install rubber end plug into rear of the actuator assembly, push until flush and snapped into place. Make sure end plug has sealed against the case. Inspect bushings and appropriate holes to make sure they are clean. Install actuator bushing into side plate. DO NOT lubricate.
3. Install timing belt actuator and actuator side plate. Torque to specification. Rotate pulley assembly into belt a maximum of 132 INCH lbs. (15 Nm.) to allow engagement of actuator shaft into pulley arm socket. Pull lock pin and discard. This releases tensioner. Torque tensioner pulley assembly to 132 INCH lbs. (15 Nm.) counterclockwise to seat pulley into belt. Tighten both right hand (rear bank) camshaft sprocket bolts to 96 ft. lbs. (130 Nm). Remove Cam Hold Down from right hand (rear bank) camshaft carrier. Rotate crankshaft 360 degrees clockwise while looking at front of engine and align crankshaft reference marks. Make sure both right hand (rear bank) camshaft flats are DOWN. Tighten both left hand (front bank) camshaft sprocket bolts to 96 ft. lbs. (130 Nm).
4. Remove Cam Hold Down from left hand (front bank) camshaft carrier. Rotate crankshaft 720 degrees clockwise while looking at front of engine to seat timing belt, and VERIFY correct timing by making sure both camshaft flatspots are UP on one bank, and DOWN on the opposing bank. (Scheme 17)
5. Install camshaft carrier covers and bolts. Torque bolts to specification. Install breather hose from rear camshaft cover, and crankcase vent from breather manifold. Install timing belt covers and bolts. Tighten bolts to specification. Install fuel line bracket and bolt. Tighten bolt to specification. Install wiring harness cover at right strut tower.
6. Install spark plug wires. Install PCM electrical connectors. Install power steering lines to pump. Install serpentine belt and tensioner. Tighten serpentine belt tensioner bolt to specification. Install coolant recovery tank. Install upper intake manifold, bolts, and nuts. Tighten to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__torque-specifications). Install power brake vacuum hose and wiring loom bracket for rear spark plug wires.
7. Install vacuum lines to upper intake manifold tee. Connect electrical connections to canister purge solenoid and map sensor. Install EGR valve and torque bolts to specification. Connect electrical connectors to EGR. Install PCV valve and vacuum line to throttle body. Install heater hose and bracket to lower intake manifold. Install fuel mounting bracket and bolt, tighten to specification. Connect fuel lines to fuel rail and install fuel rail cover. Connect accelerator and cruise control cables to throttle body. Install air cleaner assembly. Refill cooling system and bleed. See «COOLING SYSTEM BLEEDING»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__cooling-system-bleeding). Fill power steering system. Install negative battery cable.

Scheme 10

Scheme 11

Scheme 12

Scheme 13

Scheme 14

Scheme 15

Scheme 16

Scheme 17

1. Remove upper intake manifold. See «INTAKE MANIFOLD (UPPER)»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x) . Remove lower intake manifold. See «INTAKE MANIFOLD (LOWER)»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x) . Remove camshaft carrier. See «CAMSHAFT CARRIER & COVERS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x) .
2. Remove left exhaust manifold. See «EXHAUST MANIFOLD»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x) . Remove oil dipstick tube bolt. Disconnect electrical connector from temperature sending unit. Remove cylinder head bolts, cylinder head, and gasket.

1. Remove upper intake manifold. See «INTAKE MANIFOLD (UPPER)»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x) . Remove lower intake manifold. See «INTAKE MANIFOLD (LOWER)»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x) . Remove camshaft carrier. See «CAMSHAFT CARRIER & COVERS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x) .
2. Remove exhaust crossover pipe. Raise and support vehicle. Disconnect front exhaust pipe at manifold. Lower vehicle. Disconnect electrical connector from oxygen sensor. Remove rear timing belt tensioner bracket. Remove cylinder head bolts. Remove cylinder head and exhaust manifold as an assembly. Remove gasket.

Inspection (Left & Right)

Check cylinder head warpage. See CYLINDER HEAD OVERHAUL under OVERHAUL. Check cylinder block warpage. See CYLINDER BLOCK ASSEMBLY under OVERHAUL.

Ensure cylinder head bolt threads and cylinder block holes are clean. Set gasket on cylinder block with metal tabs (between cylinders) facing upward. Install cylinder head and bolts. Tighten bolts to specification in sequence. See TORQUE SPECIFICATIONS. (Scheme 18) To complete installation, reverse removal procedure.

Scheme 18

VALVE LIFTERS

Note. Mark valve lifter location for reassembly reference.

Remove camshaft carrier. See CAMSHAFT CARRIER & COVERS . Remove lifter retaining hoses and valve lifters.

Lubricate lifters with GM Lubricant (1052367). To complete installation, reverse removal procedure.

Remove right cylinder head. See CYLINDER HEAD REMOVAL . Remove oil pump drive assembly (held in place like a distributor) and "O" ring.

To install, reverse removal procedure. Apply engine oil to "O" ring. Apply grease to drive gear. Tighten bolt to specification. See TORQUE SPECIFICATIONS .

INTERMEDIATE SHAFT & BEARINGS

Note. Intermediate shaft journals are all the same diameter. Remove intermediate shaft carefully to avoid damaging bearings.

Remove engine. See ENGINE. Remove oil pump drive assembly. Refer to OIL PUMP DRIVE ASSEMBLY . Remove timing chain. Refer to TIMING CHAIN & SPROCKETS . Remove intermediate shaft thrust plate. Carefully remove intermediate shaft. If necessary, remove bearings using Bearing Remover/Installer (J-33049).

Intermediate shaft cannot be machined. If it is worn or damaged, replace it. If installing new intermediate shaft, add GM Lubricant (1052367) to engine oil.

1. Assemble Bearing Remover/Installer (J-33049). Place bearing onto remover/installer. Tap bearing into place, ensuring oil holes are indexed (on front bearing, oil holes are at 4 o'clock and 7 o'clock positions, as viewed from front of engine; on all other bearings, oil hole is at 4 o'clock position).
2. Apply engine oil to intermediate shaft journals and chain sprocket. Install intermediate shaft and thrust plate. Replace "O" ring seal after installing chain sprocket.
3. Install timing chain assembly. Refer to procedures in «TIMING CHAIN & SPROCKETS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x) . Install oil pump drive assembly. Refer to «OIL PUMP DRIVE ASSEMBLY»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x) . To complete installation, reverse removal procedures. Tighten bolts and nuts to specification. Refer to «TORQUE SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__torque-specifications) .

1. Remove air cleaner assembly. Drain cooling system. See «COOLING SYSTEM DRAINING»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__cooling-system-draining) . Remove coolant reservoir. Support engine from above with Engine Support Fixture and Adapters (J-28467-A, J-28467-90 and J-36462). Raise and support vehicle. Remove front wheels. Drain crankcase.
2. Remove steering gear (leave hoses attached), and position it aside. Separate ball joints from control arms. Remove power steering cooler line clamps at frame. Remove engine mount nuts at engine cradle (engine cradle consists of engine mounting and suspension support frame).
3. Put an adjustable jack under engine cradle. Remove engine cradle bolts. Lower engine cradle. Remove oil filter and engine oil cooler assembly. Remove engine oil level sensor. Remove starter. Remove flexplate/flywheel cover. Remove oil pan nuts and bolts. Remove oil pan and gasket.

1. Clean gasket surfaces and bolt holes. Install a NEW gasket. Apply GM Sealant (12345739) to notches at rear main bearing cap. Install oil pan. Tighten oil pan nuts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__torque-specifications) .
2. Tighten 2 rear oil pan bolts to specification. Tighten remaining oil pan bolts to specification. To complete installation, reverse removal procedures. Fill and bleed the cooling system. See «COOLING SYSTEM BLEEDING»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__cooling-system-bleeding) .

1. Remove transmission. See TRANSMISSION REMOVAL & INSTALLATION - A/T article in TRANSMISSION SERVICING section.
2. On M/T models, mark clutch pressure plate and flywheel for installation reference. Remove pressure plate, clutch disc and flywheel. On A/T models, remove flexplate and retainer.
3. On all models, careful pry seal from housing DO NOT damage sealing surfaces. Note direction of seal installation.

Inspect inner diameter of bore and seal contact area of crankshaft for nicks or burrs. Repair or replace seal housing or crankshaft as necessary.

1. Coat inner and outer seal surfaces with engine oil. Install seal on mandrel of Seal Installer (J-34686) until dust lip bottoms against seal installer collar. (Scheme 19)
2. Install seal installer onto crankshaft, aligning dowel pin on seal installer with alignment hole in crankshaft flange. To install seal in seal bore, tighten seal installer handle until collar on seal installer is even with cylinder block.
3. To complete installation, reverse removal procedure. Align reference marks on pressure plate and flywheel (M/T models). Tighten bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__torque-specifications).

Scheme 19

1. Remove air cleaner and duct assembly in order to gain access to thermostat housing.
2. Partially drain coolant (below level of thermostat.
3. Remove engine mount/torque strut bolt at engine.
4. Remove upper radiatore hose at thermostat housing.
5. If fuel lines and fuel rail need to be disconnected to obtain clearance, bleed fuel pressure from system by connecting fuel pressure gauge to pressure connector. Bleed fuel into an approved container.
6. Remove fule lines from rail if necessary.
7. Remove heater hose bracked at thermostat housing if necessary. Remove heater hoses at throttle body if necessary.
8. Remove throttle cable cover if necessary.
9. Remove thermostat housing bolts.
10. Remove thermostat housing and thermostat.

1. To install, reverse removal procedure.
2. Tighten housing bolts to 18 ft. lbs. (25 N.m).
3. Tighten engine mount/strut nuts to 35 lb ft (48 N.m).
4. Fill cooling system with appropriate mix of water and coolant.
5. Start the engine. After the engine reaches normal operating temperature, check for coolant leaks.

Remove air cleaner assembly. Remove coolant reservoir. Partially drain engine coolant. Loosen, but DO NOT remove, water pump pulley bolts. Rotate serpentine belt tensioner clockwise with a wrench, and remove belt. (Scheme 2) Remove water pump pulley. Remove water pump bolts and water pump.

Clean all mating surfaces. To install, reverse removal procedure using a NEW gasket. Tighten bolts to specification. See TORQUE SPECIFICATIONS . Fill and bleed the cooling system. Refer to procedures in COOLING SYSTEM BLEEDING .

Gasket Surface

If warpage exceeds specification, machine cylinder head. See CYLINDER HEAD table under ENGINE SPECIFICATIONS.

Valve Stem Oil Seals

Oversize valve stem oil seals are used for oversize valves. Intake and exhaust valve stem oil seals are different.

Valve Guides

If valve stem oil clearance is not within specification, ream valve guides for an oversize valve. See CYLINDER HEAD table under ENGINE SPECIFICATIONS.

Valve Seats

Seats may be reground. See CYLINDER HEAD table under ENGINE SPECIFICATIONS. Seat replacement procedure is not provided by manufacturer.

Valves

If valve margin is less than specified, replace valve. See VALVES & VALVE SPRINGS table under ENGINE SPECIFICATIONS. DO NOT lap new valves. Protective coating will be damaged if new valve is lapped. After grinding the face of an old valve, lap valve into seat.

Valve Seat Correction Angles

If seat is too wide, narrow it using a 70-degree stone (this will also raise the seat).

Valve Installed Height

Valve installed height is distance between spring seat and tip of valve stem. If height is not as specified, replace or machine components as necessary. See VALVES & VALVE SPRINGS table under ENGINE SPECIFICATIONS.

Piston & Rod Orientation

If separating piston from connecting rod, mark connecting rod in relation to piston for reassembly reference. Install piston in original cylinder with arrow or notch on top of piston toward front of engine.

Pistons Pins

Piston pins are press-fitted into pistons. If interference fit of piston pin within pin bore is not as specified, replace piston and/or pin as necessary. See PISTONS, PINS & RINGS table under ENGINE SPECIFICATIONS.

Fitting Pistons

Measure piston diameter 7/16" (11 mm) below center line of piston pin bore. Measure piston taper at center and bottom of piston skirt. DO NOT machine oversize pistons, or engine balance will be affected.

Cylinder Block Flange Runout

1. With engine removed and crankshaft installed, measure cylinder block flange runout. Mount dial indicator gauge plate flat against crankshaft flange. Place dial indicator stem on lower left transmission bolt boss (flat area around bolt hole). Adjust dial indicator to zero.
2. Observe and record readings obtained on all bolt hole bosses. Measurements should not vary more than .010" (.25 mm). If readings exceed specification, check crankshaft flange runout. See CRANKSHAFT FLANGE RUNOUT procedures below.

Installing Piston Rings

Install piston rings with identification mark toward top of piston and ring gaps properly spaced. (Scheme 20)

Tightening Main Bearing Cap Bolts (A/T)

Before tightening main bearing cap bolts, thrust crankshaft rearward (to set and align main bearing caps) then forward (to align thrust bearing face). Tighten main bearing cap bolts to specification. See TORQUE SPECIFICATIONS .

Tightening Main Bearing Cap Bolts (M/T)

Before tightening main bearing cap bolts, thrust crankshaft forward (to set and align main bearing caps) then rearward (to align thrust bearing face). Tighten main bearing cap bolts to specification. See TORQUE SPECIFICATIONS .

Crankshaft Flange Runout

1. With engine removed and crankshaft installed, or with crankshaft mounted on "V" blocks, measure crankshaft flange runout. Mount dial indicator, and place dial indicator stem on crankshaft flange. Adjust dial indicator to zero.
2. Mark reference point on crankshaft flange. Ensure crankshaft is thrust forward so end float will not affect readings. Turn crankshaft 360 degrees.
3. Observe and record readings. Reading should not vary more than .002" (.05 mm). Replace crankshaft if runout exceeds specification.

Cylinder Block Deck Warpage

If warpage exceeds specification, machine cylinder block deck. See CYLINDER BLOCK table under ENGINE SPECIFICATIONS. DO NOT remove more than .010" (.25 mm) material from original surface of deck.

Scheme 20

ENGINE LUBRICATION SYSTEM

An intermediate shaft-driven, gear-type oil pump provides pressurized lubrication. (Scheme 21) Passage above intermediate shaft bearing supplies oil to oil distribution cover assembly (with anti-drainback valve). Oil distribution cover diverts oil supply to camshaft carriers. Passages in carriers supply oil to hydraulic lifters and camshaft rear thrust plates.

Crankcase Capacity

Engine oil capacity is approximately 5 qts. (4.8L) without filter change. If changing filter, add more oil as necessary.

Oil Pressure

Minimum oil pressure is 15 psi (1.1 kg/cm 2 ) at 1100 RPM.

Scheme 21

Scheme 22

Removal & Disassembly

Remove oil pan. See OIL PAN under REMOVAL & INSTALLATION. Remove baffle. DO NOT remove pick-up tube assembly. Remove oil pump and drive shaft extension. Disassemble oil pump. Clean parts with solvent. Dry parts with compressed air.

1. Inspect components for damage. Using straightedge and feeler gauge, measure gear end clearance. Measure housing pocket depth and diameter. Measure gear diameter and length (thickness). Measure side clearance between gear tooth and housing.
2. Measure gear lash clearance between the gear teeth. Check clearance between the pressure regulator valve and bore. Replace components or pump assembly if not within specification. Refer to «OIL PUMP SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x) table.

OIL PUMP SPECIFICATIONS

Note. Use only original equipment gaskets for oil pump service. Gasket thickness is critical.

Reassembly & Installation

1. To reassemble, coat all components with engine oil. Reverse disassembly procedure using NEW pump cover gasket.
2. Install drive shaft extension and oil pump, and engage shaft extension into drive gear. Install and tighten oil pump bolt to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/lumina/i-1989-2001/remont/mechanical/#engine-mechanical-34l-v6-vin-x__torque-specifications) . To complete installation, reverse removal procedure.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

GENERAL SPECIFICATIONS

GENERAL SPECIFICATIONS

CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS

CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS

CONNECTING RODS

CONNECTING RODS

PISTONS, PINS & RINGS

PISTONS, PINS & RINGS

CYLINDER BLOCK

CYLINDER BLOCK

VALVES & VALVE SPRINGS

VALVES & VALVE SPRINGS

CYLINDER HEAD

CYLINDER HEAD

CAMSHAFT

See also:
• ENGINE OVERHAUL PROCEDURES
• FUEL PRESSURE RELEASE
• COOLING SYSTEM DRAINING
• COOLING SYSTEM BLEEDING
• TORQUE SPECIFICATIONS
• TIMING BELT & CAMSHAFT TIMING PROCEDURE
• INTAKE MANIFOLD (UPPER)