3.3l v6 - VIN [n] Buick Skylark VI

ENGINE IDENTIFICATION

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

Engine may be identified by the eighth character of Vehicle Identification Number (VIN) located on top of instrument panel near lower left corner of windshield.

Partial VIN number is stamped on cylinder block. The first character indicates manufacturer, and second character indicates the year. (Scheme 27)

ENGINE IDENTIFICATION CODES

Scheme 27

VALVE ARRANGEMENT

E-I-E-I-I-E (Left bank, front-to-rear).

E-I-I-E-I-E (Right bank, front-to-rear).

VALVE CLEARANCE ADJUSTMENT

No valve adjustment is required, as hydraulic valve lifters are used.

TROUBLE SHOOTING

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

ENGINE

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.

1. Remove negative battery cable. Remove airflow sensor wiring. Disconnect air intake duct. Drain cooling system. Disconnect upper engine strut. Raise and support vehicle.
2. Disconnect exhaust pipe. Disconnect engine mount bolts. Remove starter wiring and starter. Disconnect A/C compressor and set aside (if equipped).
3. Remove lower transaxle-to-engine bolts. One bolt is located between transaxle case and engine block and is installed in opposite direction. Remove drive plate cover. Match mark drive plate-to-torque converter relationship to assure proper reassembly. Remove drive plate-to-torque converter bolts.
4. Disconnect engine support bracket at transaxle. Lower vehicle. Remove radiator hoses. Disconnect heater hoses at engine. Remove alternator. Disconnect engine wiring harness. Remove remaining transaxle-to-engine bolts. Remove engine. To install, reverse removal procedure.

INTAKE MANIFOLD

Removal

1. Fuel pressure must be released. To release fuel pressure, raise and support vehicle. Disconnect electrical connection at fuel tank for the fuel pump. Start engine and operate until it stalls. With ignition off, reconnect electrical connection.
2. Disconnect negative battery cable. Drain cooling system. Remove serpentine belt, alternator and braces. Remove power steering pump with hoses attached.
3. Disconnect coolant by-pass hose, heater pipe and upper radiator hose. Disconnect control cables and air intake from throttle body. Disconnect necessary electrical connections, vacuum lines and fuel lines.
4. Disconnect rear spark plug wires. It may be necessary to remove fuel rail to gain access to intake manifold bolts. Remove intake manifold bolts, manifold, gaskets and seals.

Installation

1. Ensure sealing surfaces and bolt threads and holes are clean. Apply GM Sealant (12345336) at the end of seals on cylinder block. Install manifold and gaskets. Coat bolt threads with thread sealant and install.
2. Tighten intake manifold bolts in sequence TWICE to 88 INCH lbs. (10 N.m). (Scheme 28) Lubricate coolant "O" rings with anti-freeze and fuel rail "O" rings with engine oil prior to installation. To install remaining components, reverse removal procedure. Fill cooling system.

Scheme 28

Removal & Installation - Left Side (Front)

1. Disconnect negative battery cable. It may be necessary to remove air inlet duct. Disconnect spark plug wires. Remove crossover pipe bolts from manifold.
2. Remove engine lift hook and manifold heat shield (if equipped). Remove oil dipstick and tube. Remove manifold bolts, manifold and gasket. To install, reverse removal procedure using new gasket.

Removal & Installation - Right Side (Rear)

1. Disconnect negative battery cable. Disconnect spark plug wires and oxygen sensor. Remove EGR pipe (if equipped). It may be necessary to disconnect throttle cable from throttle body and brake booster hose.
2. Disconnect crossover pipe and exhaust pipe from manifold. Remove transaxle dipstick. Remove manifold heat shield (if equipped). Remove manifold bolts, manifold and gasket. To install, reverse removal procedure using new gasket.

1. Remove intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in this article. Remove exhaust manifold. See EXHAUST MANIFOLD under REMOVAL & INSTALLATION in this article.
2. On front cylinder head applications, disconnect spark plug wires. Remove alternator and bracket with ignition coil attached. Remove A/C compressor bracket bolt.
3. On rear cylinder head applications, disconnect spark plug wires. Remove power steering pump with hoses attached and lay aside. Remove belt tensioner assembly and fuel line heat shield (if equipped).
4. Remove rocker arms, push rods and guide plates. See ROCKER ARMS & PUSH RODS under REMOVAL & INSTALLATION in this article. Remove cylinder head bolts, cylinder head and gasket.

Inspection

Inspect cylinder head warpage. See CYLINDER HEAD under OVERHAUL in this article.

1. Ensure cylinder head bolt threads and cylinder block holes are clean. Ensure all holes align with cylinder block.
2. Install cylinder head. Apply GM Sealant (1052080) to head bolt threads and install. Tighten all bolts to 35 ft. lbs. (47 N.m) in proper sequence. (Scheme 29) Tighten all bolts an additional 130 degrees in proper sequence.
3. Tighten the center four bolts an additional 30 degrees in proper sequence. CAUTION: Cylinder head bolts must be coated with GM Sealant (1052080) prior to installation. Tighten all bolts to 35 lbs. (47 N.m) in proper sequence. (Scheme 29) Tighten all bolts an additional 130 degrees in proper sequence. On 3.3L models, tighten the center four bolts an additional 30 degrees in proper sequence.
4. To install remaining components, reverse removal procedure. Coat rocker arm bolts with GM Sealant (1052624) prior to installation. Ensure all components are installed in original location.

Scheme 29

1. Remove front timing case cover. See FRONT TIMING CASE COVER under REMOVAL & INSTALLATION in this article. Remove camshaft button and spring from front of camshaft. (Scheme 31)
2. Inspect timing chain and sprockets for wear. Timing chain in and out movement should not exceed 1" (25.4 mm). Replace if necessary.
3. Rotate crankshaft and align timing marks on camshaft and crankshaft sprockets. (Scheme 30) Remove timing chain damper assembly. (Scheme 30)
4. Remove camshaft sprocket bolts. Remove camshaft sprocket and timing chain. Remove crankshaft sprocket (if necessary).

Scheme 30

1. If engine has been rotated, rotate crankshaft so No. 1 cylinder is at TDC. Temporarily install camshaft sprocket. Rotate camshaft sprocket so timing mark is downward.
2. Remove camshaft sprocket and install timing chain on camshaft sprocket. Install timing chain and camshaft sprocket. Ensure timing marks are aligned. (Scheme 30) Install camshaft sprocket bolts. Install camshaft button and spring.
3. To install remaining components, reverse removal procedure. Ensure timing marks are aligned.

Scheme 31

1. Disconnect negative battery cable. Drain cooling system. Remove serpentine belt. Disconnect heater pipes. Disconnect coolant hoses at case cover.
2. Raise and support vehicle. Remove right front wheel and inner splash shield. Remove crankshaft balancer bolt and crankshaft balancer. Disconnect electrical connections at oil pressure sender, camshaft sensor and crankshaft sensor.
3. Remove oil pan-to-case cover bolts. Remove front timing case cover bolts, case cover and gasket.

Scheme 32

1. Inspect timing chain and sprockets for wear. Timing chain in and out movement should not exceed 1" (25.4 mm). Replace if necessary.
2. To install, reverse removal procedure using new gasket. Coat case cover bolts with thread sealant prior to installation. Crankshaft sensor must be adjusted.
3. With crankshaft sensor mounted loosely on mounting pedestal, install sensor and mounting pedestal on Crankshaft Sensor Adjuster (J-37089). (Scheme 32) Install crankshaft sensor adjuster and sensor assembly on crankshaft.
4. Install mounting pedestal-to-cylinder block bolts and tighten to 14-28 ft. lbs. (19-38 N.m). Install sensor-to-mounting pedestal bolts to 30-35 INCH lbs. (3.3-3.9 N.m). 5) Remove crankshaft sensor adjuster from crankshaft. Place sensor adjuster inside the crankshaft balancer. Rotate sensor adjuster. Replace crankshaft balancer if sensor adjuster contacts balancer at any point.
5. To install remaining components, reverse removal procedure. Coat outside surface of crankshaft balancer and seal with oil prior to installation.

1. Disconnect negative battery cable. Remove serpentine belt. Raise and support vehicle. Remove right front wheel and inner splash shield.
2. Remove crankshaft balancer bolt and crankshaft balancer. Pry seal from front timing case cover.

1. Using Seal Installer (J-35354) and crankshaft balancer bolt, install seal. Remove seal installer.
2. Coat outside surface of crankshaft balancer and seal with oil prior to installation. To install remaining components, reverse removal procedure.

1. Disconnect negative battery cable. Remove serpentine belt. For left (front) valve cover removal, remove alternator brace and spark plug wires.
2. For right (rear) valve cover removal, loosen power steering pump bolts and move pump forward. Remove power steering pump braces.
3. Remove spark plug wires and valve cover. Remove rocker arm pedestal bolts. Remove rocker arms and components. (Scheme 33) Mark component location for reassembly reference.

Scheme 33

To install, reverse removal procedure. Coat rocker arm bolts with GM Sealant (1052624) prior to installation. Apply thread sealant to valve cover bolts prior to installation.

1. Remove intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in this article. Remove rocker arms and push rods. See ROCKER ARMS & PUSH RODS under REMOVAL & INSTALLATION in this article.
2. Remove push rod guide bolts and push rod guide. (Scheme 33) Remove valve lifter guide and valve lifter. Mark component location for reassembly reference.

To install, reverse removal procedure. Apply Engine Oil Supplement (1052367) to valve lifter prior to installation. Ensure components are installed in original location.

BALANCE SHAFT

Note. Engine must be removed for balance shaft service.

1. Remove engine. See ENGINE REMOVAL & INSTALLATION article in this section
2. Remove flywheel. Remove intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in this article. Remove lifter guide retainer. (Scheme 33)
3. Remove front timing case cover. See FRONT TIMING CASE COVER under REMOVAL & INSTALLATION in this article. Remove balance shaft gear bolt. Remove camshaft sprocket and timing chain.
4. Remove bolts from balance shaft retainer. Remove balance shaft retainer and balance shaft gear. Install Slide Hammer (J-6125-B) in front of balance shaft and remove balance shaft. Remove balance shaft plug from rear of cylinder block.
5. Note direction of rear bearing installation. Using Rear Bearing Remover (J-36995-5), remove bearing from block.

Note. Balance shaft and bearings are serviced as complete assembly only. Proper installation tools must be used to prevent balance shaft damage.

Inspect components for damage. Measure bearing bore I.D. Replace components if not within specification. See BALANCE SHAFT SPECIFICATIONS table.

Scheme 34

1. Lubricate balance shaft bearings with engine oil. Rear bearing must be installed with rolled edge facing inward toward the engine and manufacturer's marking facing flywheel side of engine. Using Rear Bearing Installer (J-36995-1), install rear bearing. CAUTION: Balance shaft rear bearing must be installed with rolled edge facing inward toward the engine and manufacturer's marking facing flywheel side of engine.
2. Using Balance Shaft Installer (J-36996), install balance shaft. Temporarily install balance shaft retainer and bolts. Install balance shaft gear. Apply thread sealant to gear retaining bolt and install. Tighten gear retaining bolt to specification. Refer to «TORQUE SPECIFICATIONS»(/buick/skylark/vi-1986-1992/remont/mechanical/#33l-v6-vin-n__torque-specifications) table at end of article.
3. Install balance shaft rear plug. Using dial indicator, measure balance shaft end play and radial clearance at front and rear of balance shaft. (Scheme 34) Replace components if not within specification. See BALANCE SHAFT SPECIFICATIONS table.
4. Rotate camshaft so when sprocket is installed, timing mark is downward. With camshaft sprocket and gear removed, rotate balance shaft so that timing mark on gear is downward.
5. Align timing marks on camshaft gear and balance shaft gear by rotating balance shaft and install camshaft gear. (Scheme 30) Rotate crankshaft so No. 1 piston is at TDC. Install timing chain and sprocket. Ensure timing marks are aligned. (Scheme 30)
6. Using dial indicator, measure gear lash at four places. Gear lash should be within specification. See BALANCE SHAFT SPECIFICATIONS table. If all measurements are within specification, tighten balance shaft retainer bolts to specification. To install remaining components, reverse removal procedure.

BALANCE SHAFT SPECIFICATIONS

Removal & Installation

Disconnect negative battery cable. Drain cooling system. Remove water pump drive belt. Disconnect necessary coolant hoses. Remove water pump pulley. Remove water pump bolts, water pump and gasket. To install, reverse removal procedure using new gasket. Fill cooling system.

OIL PAN

Disconnect negative battery cable. Raise and support vehicle. Drain crankcase. Remove flywheel access cover and crossover pipe. Disconnect engine mounts. Raise and support engine. Remove oil pan bolts and oil pan.

1. Inspect cylinder head for warpage at deck surface and manifold surfaces. Resurface cylinder head if warpage exceeds specification. See ENGINE SPECIFICATIONS tables at end of article.
2. Amount of metal removed from cylinder head should be checked to determine if head can be used. To determine amount removed, use depth micrometer and measure the distance from deck surface to the 3 cast pads. (Scheme 35)
3. Measurement should be from.054-.066" (1.37-1.68 mm) on new cylinder heads. Minimum dimension is.044" (1.12 mm). Replace cylinder head if measurement is less than minimum dimension.

Scheme 35

VALVE SEATS

No replacement procedure is given from manufacturer.

VALVE GUIDES

Valve guides must be reamed for an oversized valve if valve stem oil clearance is not within specification. See ENGINE SPECIFICATIONS tables at end of article.

SEAT CORRECTION ANGLES

After grinding, if seat width is too wide, a 20 or 70 degree stone can be used to reduce seat width. The 20 degree stone will lower the seat, as the 70 degree stone will raise the seat.

Valve Spring Installed Height

1. Install valve, valve retainer and keepers. Pull upward on valve and measure height from top of spring seat to spring side of the valve retainer. (Scheme 36)
2. Spring installed height must be within specification. See ENGINE SPECIFICATIONS tables at end of article. If measurement exceeds specification, add shims under the valve spring to obtain correct height.

Scheme 36

VALVE STEM HEIGHT

With valve installed in cylinder and in closed position, use steel ruler to measure distance from spring seat to the valve tip. Distance should be 1.935-1.975" (49.15-50.16 mm).

VALVE STEM OIL SEALS

Oversized valve stem oil seals are used for oversized valves. Intake and exhaust valve stem oil seals are different. Proper oil seal must be installed according to part number.

1. Remove engine. See ENGINE REMOVAL & INSTALLATION article at end of ENGINE section. Remove intake manifold. See INTAKE MANIFOLD under REMOVAL & INSTALLATION in this article.
2. Remove rocker arms and push rods. See ROCKER ARMS & PUSH RODS under REMOVAL & INSTALLATION in this article. Remove valve lifters. Remove timing chain and sprockets. See TIMING CHAIN & SPROCKETS under REMOVAL & INSTALLATION in this article. Remove camshaft and bearings (if required).

Inspect camshaft journal diameter, lobe lift and oil clearance. See ENGINE SPECIFICATIONS tables at end of article. Replace components if not within specification.

1. Install camshaft bearings (if removed). Ensure oil holes are aligned. Apply Sealant (1052914) to rear camshaft plug prior to installation. Lubricate camshaft bearings and camshaft lobes with GM Lubricant (1052365) prior to installation. Install camshaft.
2. To install remaining components, reverse removal procedure. Ensure components are installed in original location and all timing marks are aligned.

PISTON RING INSTALLATION

Piston rings must be installed with identification mark toward top of piston and rings properly spaced. (Scheme 37)

Scheme 37

PISTON & ROD ASSEMBLY

Piston can be installed on connecting rod in either direction. Piston and connecting rod must be installed with NOTCH on top of the piston toward the front of engine.

FITTING PISTONS

Piston diameter should be measured 1.65" (41.9 mm) from top of piston. Oversized pistons must not be machined down or engine balance will be affected.

CRANKSHAFT & BEARINGS

1. Rear crankshaft oil seal must be installed prior to crankshaft installation. See REAR CRANKSHAFT OIL SEAL under OVERHAUL in this article.
2. To align crankshaft thrust surfaces, install all bearings and main caps and tighten all bolts evenly. Loosen all bolts one turn.
3. Retighten all bolts to 90 ft. lbs. (122 N.m). Using wooden mallet, carefully tap crankshaft forward then backward to align thrust bearing.

CRANKSHAFT FLANGE RUNOUT

1. With engine removed and crankshaft installed, measure crankshaft flange runout. Mount dial indicator gauge plate flat against crankshaft flange. Place dial indicator stem on lower left transmission mounting bolt boss (flat area around bolt hole). Adjust indicator to zero.
2. Observe and record readings obtained on all mounting bolt hole bosses. Measurements should not vary more than .010" (.25 mm). If readings exceed specification, remount dial gauge plate and recheck flange runout. Replace crankshaft if runout exceeds specification.

REAR CRANKSHAFT OIL SEAL

1. For seal replacement, engine must be removed. See ENGINE REMOVAL & INSTALLATION article at end of ENGINE section. Remove oil pan. See appropriate OIL PAN REMOVAL article in this section.
2. Remove crankshaft. Remove rope seal from cylinder block and main bearing cap. Ensure seal areas are clean. Apply GM Adhesive (1052621) to seal grooves.
3. Install seal in grooves so that no more than 1/16" of the seal extends above cylinder block or main bearing cap. Ensure seal is fully seated. Cut ends of seal even with surface.
4. Coat rope seal with thin film of grease. Install crankshaft. Apply GM Sealant (1052942) on main bearing-to-cylinder block mating surfaces. DO NOT allow sealant to enter bolt threads. CAUTION: Sealing strips used along the side of main bearing cap must be soaked in light oil or kerosene for 5 minutes prior to installation.
5. Install main bearing cap and sealing strips. Tighten main bearing cap bolts to specification.

CYLINDER BLOCK INSPECTION

Using feeler gauge and straightedge, inspect deck surface for warpage. Replace cylinder block if more than .010" (.25 mm) material is removed from deck surface.

ENGINE OILING SYSTEM

The crankshaft driven gear-type oil pump provides pressurized lubrication to the main gallery. (Scheme 38) Oil pump and pressure regulator valve are located in the front timing case cover.

Scheme 38

CRANKCASE CAPACITY

Engine oil capacity is approximately 4 qts. (3.7L) with filter change. Recheck oil level after changing filter.

NORMAL OIL PRESSURE

Normal oil pressure is 40 psi (2.8) at 1850 RPM with 5W-30 engine oil and engine at normal operating temperature.

Remove front timing case cover. See FRONT TIMING CASE COVER under REMOVAL & INSTALLATION in this article. Remove oil filter adapter, gasket, pressure regulator and valve from front timing case cover. Remove pump cover and gears from case cover.

1. Inspect components for damage. Measure gear end clearance. Measure housing gear pocket depth and diameter. Measure outer gear-to-housing clearance and tip clearance between gears.
2. Check clearance between pressure regulator valve and bore. Replace components or pump assembly if not within specification. See OIL PUMP SPECIFICATIONS table.

OIL PUMP SPECIFICATIONS

Reassembly & Installation

To reassemble, reverse disassembly procedure. Lubricate all gears and fill cavities with petroleum jelly. Install pump cover. To install, reverse removal procedure.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

ENGINE SPECIFICATIONS

GENERAL SPECIFICATIONS

PISTONS, PINS & RINGS SPECIFICATIONS

CRANKSHAFT MAIN & CONNECTING ROD BEARINGS SPECIFICATIONS

CONNECTING ROD SPECIFICATIONS

CYLINDER HEAD SPECIFICATIONS

CYLINDER BLOCK SPECIFICATIONS

VALVES & VALVE SPRINGS SPECIFICATIONS

CAMSHAFT SPECIFICATIONS

See also:
• ENGINE OVERHAUL PROCEDURES - GENERAL INFORMATION
• TORQUE SPECIFICATIONS