Contents Wiring diagrams Section: Mechanical All sections

5.0L v8 - VIN [E] Chevrolet Caprice IV

Mechanical 6 illustrations ~2796 words

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 using Vehicle Identification Number (VIN) stamped on a metal pad, located near lower left corner of windshield. The eighth character identifies the engine model. See ENGINE IDENTIFICATION CODES table.

Engine identification code, located on cylinder block below cylinder head, may be required when ordering replacement parts.

ApplicationEngine CodeVIN Code
TBILO3E

ENGINE IDENTIFICATION CODES

VALVE CLEARANCE ADJUSTMENT

Note. Normally, valve adjustment is not required. If valve train components are disassembled or replaced, use adjustment procedure.

  1. Bring No. 1 cylinder to firing position and align timing marks on front cover and harmonic balancer. Adjust exhaust valves on cylinders No. 1, 3, 4 and 8 by backing off adjusting nut until valve lash is felt at push rod.
  2. Tighten adjusting nut (while rotating push rod) until valve lash is eliminated. Tighten adjusting nut an additional 3/4 - 1 1/4 turns. Repeat adjustment on intake valves for cylinders No. 1, 2, 5, and 7.
  3. Turn engine one revolution to firing position for cylinder No. 6. Adjust exhaust valves on cylinders No. 2, 5, 6 and 7. Adjust intake valves on cylinders No. 3, 4, 6 and 8.

REMOVAL & INSTALLATION

CAUTIONWhen battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES article in the GENERAL INFORMATION section before disconnecting battery.

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

TBI

turned off. To release fuel tank pressure, remove gas cap.

Removal

  1. Release fuel pressure. See FUEL PRESSURE RELEASE under REMOVAL & INSTALLATION. Disconnect negative battery cable. Remove hood and air cleaner. Drain coolant from radiator. Disconnect radiator hoses and heater hoses from engine. Remove upper fan shroud and fan assembly.
  2. Remove serpentine belt. Remove power steering pump and A/C compressor, and position aside. Disconnect throttle cable. Disconnect cooler lines (if equipped) at radiator. Remove radiator.
  3. Disconnect vacuum hoses. Disconnect engine wiring harness (including ground strap) at engine bulkhead. Remove windshield wiper motor. Disconnect ECM wiring harness.
  4. Disconnect Air Injection Reactor (AIR) hose at pipe from converter. Remove MAP sensor (if equipped).
  5. Remove distributor cap and distributor. Disconnect cruise control cable. Disconnect positive battery cable at starter. Disconnect negative battery cable at engine block. Raise and support vehicle.
  6. Remove crossover pipe and catalytic converter as an assembly. Remove flexplate cover. Remove torque converter-to-flywheel bolts. Remove motor mount bolts. Disconnect fuel hose from front fuel pipes. Disconnect torque converter clutch wiring at transmission.
  7. Disconnect transmission cooler lines at clip on engine oil pan. Remove transmission-to-engine bolts. Remove ground wires from rear of cylinder head. Lower vehicle. Support transmission. Install lifting device, and remove engine.

Installation

To install, reverse removal procedure. Fill cooling system. See WATER PUMP under REMOVAL & INSTALLATION.

  1. Disconnect negative battery cable, and drain cooling system. Remove air cleaner assembly. Disconnect fuel lines at throttle body. Disconnect ECM wiring harness, and position aside. Remove upper radiator hose at thermostat and heater hose at intake manifold.
  2. Disconnect brake booster hose. Mark and remove necessary electrical connectors and vacuum hoses. Mark and remove necessary fuel line clips and lines. Remove throttle cable bracket. Mark and remove spark plug wires at distributor cap. Remove EGR valve and solenoid. Remove distributor cap.
  3. Mark distributor rotor position for installation reference. Remove distributor. Remove ignition coil and coolant temperature sensor. Remove A/C compressor brace. Remove intake manifold and gasket.

Clean gasket surfaces. Apply 3/16" bead of RTV Sealer (1052289) onto front and rear of cylinder block and 1/2" onto each cylinder head. Install gaskets and intake manifold. Tighten bolts and studs to specification in sequence. (Scheme 7) See TORQUE SPECIFICATIONS. To complete installation, reverse removal procedure. Adjust timing (if necessary) and check for leaks.

Scheme 7

Scheme 7: Installation

Removal (Left)

  1. Disconnect negative battery cable. Raise and support vehicle.
  2. Disconnect oxygen sensor electrical connector. Remove exhaust crossover pipe at exhaust manifold. Lower vehicle. Remove air cleaner. Remove spark plug wires and clips. Remove AIR pipe and check valve as an assembly. Remove exhaust manifold heat shields, exhaust manifold and gasket.

Removal (Right)

  1. Disconnect negative battery cable. Raise and support vehicle.
  2. Remove exhaust crossover pipe at exhaust manifold. Lower vehicle. Remove air cleaner. Remove Air Injection Reactor (AIR) hoses. Mark and disconnect spark plug wires at spark plugs. Remove necessary accessory brackets.
  3. Remove exhaust manifold and gasket (if equipped).

Installation (Left & Right)

To install, reverse removal procedure. Tighten studs/bolts to specification. See TORQUE SPECIFICATIONS.

CYLINDER HEAD

Note. Check and record compression before removing cylinder head. Remove cylinder head when engine is cold.

  1. Disconnect negative battery cable. Remove intake manifold, exhaust manifold and valve covers. See INTAKE MANIFOLD, EXHAUST MANIFOLD and VALVE COVERS.
  2. Remove serpentine belt. Drain cooling system. Remove rocker arms and push rods. Ensure components are kept in order for installation reference. Remove cylinder head bolts in 3 steps in reverse order of tightening sequence. (Scheme 8) Remove cylinder head and gasket.

Inspection

Clean carbon and gasket material from mating surfaces. Check cylinder head for warpage and cracks. Clean cylinder head bolt holes and threads.

  1. Coat steel-type head gaskets with sealer. DO NOT coat composition-type head gaskets with sealer. Install head gasket onto cylinder block. Install cylinder head. Coat head bolts with Sealing Compound (1052080).
  2. Tighten bolts to specification in 3 steps in sequence. (Scheme 8) To complete installation, reverse removal procedure.

Scheme 8

Scheme 8

FRONT COVER & OIL SEAL

Note. On TBI engines, it is not necessary to remove cover to replace seal.

  1. Disconnect negative battery cable and serpentine drive belt. Remove crankshaft pulley. Loosen or remove motor mount nuts as necessary for harmonic balancer removal.
  2. Remove harmonic balancer-to-crankshaft bolt. Mark position and remove harmonic balancer using Harmonic Balancer Remover/Installer (J-39046).
  3. Remove oil pan. See OIL PAN under REMOVAL & INSTALLATION. Remove water pump. See WATER PUMP under REMOVAL & INSTALLATION.
  4. Remove front cover and gasket. Carefully pry seal from timing cover using a large screwdriver.
  1. Using Seal Aligner/Installer (J-35468), install new oil seal in timing cover. Coat timing cover gasket with sealant, and position onto timing cover. Install timing cover.
  2. Tighten bolts alternately and to specification. See TORQUE SPECIFICATIONS. Apply sealant to oil pan, cylinder block and timing cover joint. To complete installation, reverse removal procedure.
  1. Disconnect negative battery cable. Remove front cover. See FRONT COVER & OIL SEAL. Rotate crankshaft until camshaft sprocket and crankshaft sprocket timing marks line up with shaft centers. (Scheme 10)
  2. Remove camshaft sprocket and chain as an assembly. (Scheme 9) If replacing crankshaft sprocket, use Sprocket Remover (J-5825-A) to pull sprocket off crankshaft.

Drive crankshaft sprocket onto crankshaft, with timing mark facing out. Ensure timing marks on crankshaft sprocket and camshaft sprocket are as close together as possible and lined up with shaft centers. (Scheme 10) Install camshaft sprocket and chain as an assembly. To complete installation, reverse removal procedure.

Scheme 9

Scheme 9: Installation

Scheme 10

Scheme 10
  1. Disconnect negative battery cable.
  2. Remove air cleaner, power brake pipe, PCV valve and hose at valve cover. Remove fuel lines and brackets. Remove valve cover bolts, washers, valve cover and gasket.
  1. Disconnect negative battery cable.
  2. Remove air cleaner. Disconnect ECM harness connectors and position harness aside. Remove AIR diverter valve and hoses. Remove spark plug wires at distributor. Remove EGR solenoid bracket. Disconnect PCV hose and connector. Remove valve cover and gasket.

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

  1. Remove valve covers. See VALVE COVERS. Keep components in order for installation in original location and position.
  2. Remove rocker arm nuts, balls, rocker arms and push rods. To install, reverse removal procedure. Apply Prelube (1052365) to rocker arm and ball mating surface. See VALVE CLEARANCE ADJUSTMENT under ADJUSTMENTS.
  1. Remove rocker arms and push rods as necessary. See ROCKER ARMS & PUSH RODS under REMOVAL & INSTALLATION. Remove rocker arm stud(s) using Stud Remover (J-5802-01). Ream stud bore to replacement size of oversize stud. Oversize studs are available in .003" (.08 mm) and .013" (.33 mm).
  2. Coat press-fit area of stud with hypoid axle lubricant. Install rocker arm stud using Stud Installer (J-6880) until installer bottoms out on cylinder head. To complete installation, reverse removal procedure.

CAMSHAFT

Note. Rotate crankshaft in direction of normal operation only. Keep components in order for installation reference.

  1. Remove valve covers and rocker arms. DO NOT remove push rods. See VALVE COVERS and ROCKER ARMS & PUSH RODS. Measure lobe lift of camshaft with push rods installed.
  2. To measure lobe lift, attach dial indicator to cylinder head. Position indicator pointer onto tip of a push rod. Rotate crankshaft until push rod is at lowest point. Zero indicator, and rotate crankshaft until push rod is at highest point. Record reading, and repeat procedure for remaining lobes.
  3. After lobe lift is measured, remove push rods. Remove intake manifold and timing sprockets. See INTAKE MANIFOLD and TIMING CHAIN under REMOVAL & INSTALLATION.
  4. Remove upper radiator fan shroud. Remove radiator and hoses. Discharge A/C system and remove condenser (if equipped).
  5. Remove valve lifters and camshaft retaining plate. Using three5/16" x 18" x 4" bolts as a handle, carefully pull camshaft from engine. Remove camshaft rear plug and bearings as necessary.

Check camshaft for scratches, pits and loose fit in bearings. Check camshaft journal diameter and lobe lift (recorded earlier). See CAMSHAFT table under ENGINE SPECIFICATIONS. Replace camshaft if damaged or not to specification.

  1. Install front and rear bearings. On Brougham, position camshaft bearing No. 1 oil holes at equal distance from 6 o'clock position. On all other models, position camshaft bearing No. 1 oil holes at 1 o'clock and 5 o'clock positions.
  2. Position oil hole of rear bearing at 12 o'clock position. Position oil holes of middle bearings at 5 o'clock position toward left side of engine and even with bottom of cylinder bore.
  3. Install camshaft rear plug flush to .031" (.79 mm) deep in block. Use Sealant (1052080) on camshaft plug. If replacing camshaft, replace lifters, engine oil and filter.
  4. Apply Camshaft Prelube (1052365) to camshaft lobes. Apply engine oil to bearings and camshaft bearing journals. To complete installation, reverse removal procedure.

Remove transmission. Remove flywheel/flexplate. Pry out seal using screwdriver at notches in seal retainer. (Scheme 11)

  1. Coat entire seal with engine oil. Install seal using Seal Installer (J-35621) until installer bottoms. (Scheme 11) Align crankshaft dowel to flywheel hole.
  2. Install flywheel/flexplate-to-crankshaft bolts. Tighten bolts to specification. See TORQUE SPECIFICATIONS. To complete installation, reverse removal procedure.

Scheme 11

Scheme 11
  1. Disconnect negative battery cable, and drain cooling system. Remove air cleaner and intake duct assembly.
  2. Remove accessory drive belt(s), fan, pulley and accessories as necessary. Remove coolant hoses from water pump. Remove water pump and gasket.
  1. To install, reverse removal procedure. Fill and bleed cooling system.
  2. Leave radiator (or surge tank) cap off. Start and run engine until upper hose is hot. With engine at idle, add coolant until level is at bottom of neck of radiator or surge tank. Fill coolant recovery reservoir to COLD mark.
  3. Install coolant recovery reservoir cap. Run engine until radiator inlet hose is hot. Add coolant to reservoir to maintain level. Fill coolant recovery reservoir to HOT mark.
  1. Disconnect negative battery cable. Remove air cleaner and fan shroud. On all models except Brougham, remove spark plug wires and distributor cap.
  2. Raise and support vehicle. Drain crankcase oil. Disconnect oil level sensor and remove sensor (if equipped).
  3. Disconnect exhaust pipe from manifold, Air Injection Reactor (AIR) pipe clamp and catalytic converter hanger. Remove exhaust crossover pipe at manifold and converter.
  4. Remove starter and flexplate cover. Disconnect transmission line bracket at oil pan. Remove engine mount through bolts. Remove oil pan bolts. Lower pan.
  5. Turn crankshaft timing mark to 6 o'clock position. Raise engine. Remove oil pan.

To install, reverse removal procedure. Apply Sealant (1052914) to front cover, cylinder block, rear seal retainer and cylinder block junction. Install NEW oil pan gasket. Tighten bolts and nuts to specification. See TORQUE SPECIFICATIONS.

OVERHAUL

Note. Mark components to ensure installation in original location and position.

Valve Guides

Check and service guides before servicing valve and seat. Guide replacement information is not available from manufacturer. Valve guides may be reamed for installation of .003" (.08 mm), .015" (.38 mm) or .030" (.76 mm) oversize valves.

Valve Seat

Valve seat replacement information is not available from manufacturer. Follow instructions of tool manufacturer for servicing valve seats. If seats are serviced, service or replace valves.

Valves

Check valves before servicing. Replace valves as necessary. See VALVES & VALVE SPRINGS table under ENGINE SPECIFICATIONS. Valves may be refaced.

Valve Seat Correction Angles

If seat is too wide after grinding, use a 20-degree stone to lower or a 70-degree stone to raise seat.

Piston & Rod Assembly

  1. Mark rod and rod cap with matching cylinder number. Before disassembling, mark piston to rod for reassembly reference. Notch or dot on piston top should face front of engine. Piston pin is a press fit.
  2. When measuring, ensure pin bore and piston pin are free of varnish and scuffing. If piston-to-pin clearance exceeds .001" (.03 mm), replace piston and pin as an assembly.

Fitting Pistons

Ensure notch or dot on piston top faces front of engine. Check pistons for wear and damage. Replace pistons as necessary. Check piston-to-cylinder bore clearance. If one cylinder needs to be bored, bore all cylinders to same oversize.

Piston Rings

Install marked side of ring toward top of piston. Top compression ring is chrome or molybdenum faced. Second compression ring has a tapered face. Oil ring is a 3-piece type. Ensure end gaps are evenly spaced on piston. (Scheme 12)

Scheme 12

Scheme 12: Piston Rings

Note. Rod and main bearings are available in .001" (.03 mm) and .002" (.05) undersize for oil clearance adjustment.

Rod Bearings

Ensure bearing cap bolt holes and mating surfaces are clean and dry. Use connecting rod stud protectors on rod cap bolts. Install inserts in connecting rod and cap. Lubricate bearings and crank pin. Install bearing cap. Tighten rod bearing cap bolts to specification. See TORQUE SPECIFICATIONS.

Crankshaft & Main Bearings

  1. If bearing clearance is greater than specification, replace with undersized bearings. See CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS table under ENGINE SPECIFICATIONS. Recheck bearing clearance using Plastigage.
  2. Tighten main bearing caps finger tight. Pry crankshaft rearward and then forward to align rear main bearing thrust surfaces. Retighten main bearing caps to specification. See TORQUE SPECIFICATIONS.

Thrust Bearing

Check crankshaft end play by forcing crankshaft to extreme forward position. Measure end play at front of rear main bearing using a feeler gauge. If end play is not within specification, replace thrust bearing and/or crankshaft. See CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS table under ENGINE SPECIFICATIONS.

Cylinder Block

Check cylinder bore for wear, taper, out-of-round and piston fit. See CYLINDER BLOCK table under ENGINE SPECIFICATIONS. Cylinders with less than .005" (.13 mm) wear or taper can be honed. Cylinders with more than .005" (.13 mm) wear or taper should be bored to smallest oversize piston which will permit complete resurfacing of all cylinders.

Description

A gear-type oil pump provides pressurized lubrication through the full-flow oil filter. Oil pump is bolted to bottom of cylinder block, inside oil pan. Oil pump is driven (through intermediate shaft) by gear located at rear of camshaft.

Crankcase Capacity

Crankcase capacity is 4 qts. (3.8L) without oil filter change or 4.5 qts. (4.3L) with oil filter change.

Oil Pressure

With engine at normal operating temperature, oil pressure should be at least 6 psi (0.4 kg/cm 2 ) at 1000 RPM, 18 psi (1.3 kg/cm 2 ) at 2000 RPM and 24 psi (1.7 kg/cm 2 ) at 4000 RPM.

Removal & Disassembly

  1. Remove oil pan. See OIL PAN under REMOVAL & INSTALLATION. Remove oil pan baffle (if equipped). Remove oil pump assembly and intermediate shaft.
  2. Remove oil pump cover screws, and remove cover. Mark gear teeth for reassembly reference. Remove gears. Remove pressure regulator pin, spring and valve from cover. Remove pick-up screen and pipe from cover only if replacing.

Check oil pump body and gears for cracks, wear and damage. Check oil pump shaft for looseness in housing. Check inside of cover for wear or oil leakage. If excess wear or damage is found, replace oil pump as an assembly. Oil pump specifications are not available from manufacturer.

Reassembly & Installation

Clean parts in solvent. Dry parts using compressed air. To assemble, reverse disassembly procedure. To install, reverse removal procedure.

Note. For engine code and VIN identification, see ENGINE IDENTIFICATION CODES table.

TORQUE SPECIFICATIONS

ApplicationFt. Lbs. (N.m)
Camshaft Sprocket Bolt21 (29)
Connecting Rod Cap Nut44 (60)
Crankshaft Pulley Bolt43 (58)
Cylinder Head Bolt (1)68 (92)
Exhaust Manifold Bolt/Stud
End Bolt/Stud20 (27)
Center Bolt/Stud25 (34)
Flexplate/Flywheel-To-Crankshaft Bolt(2) 74 (100)
Harmonic Balancer (Damper) Bolt70 (95)
Intake Manifold (3)
Step 111 (15)
Step 235 (47)
Main Bearing Cap Bolt77 (104)
Oil Pan Corner Bolt/Nut15 (20)
Oil Pump Bolt77 (104)
Torque Converter-To-Flexplate Bolt46 (62)
Water Pump Pulley Bolt22 (30)
Water Pump-To-Block Bolt30 (41)
INCH Lbs. (N.m)
Front Cover Bolt97 (11)
Oil Pan Bolt & Nut (Except Corners)97 (11)
Valve Cover Bolt97 (11)
(1) Tighten in sequence (in 3 passes). (Scheme 8) (2) Tighten bolts evenly using a crisscross sequence. (3) Tighten bolts evenly and in sequence. (Scheme 7)
(1)Tighten in sequence (in 3 passes). (Scheme 8)
(2)Tighten bolts evenly using a crisscross sequence.
(3)Tighten bolts evenly and in sequence. (Scheme 7)

TORQUE SPECIFICATIONS

GENERAL ENGINE SPECIFICATIONS

ApplicationSpecification
Displacement305 Cu. In. (5.0L)
Bore3.74" (95.0 mm)
Stroke3.48" (88.4 mm)
Compression Ratio9.1:1
Fuel SystemTBI
Horsepower @ RPM170 @ 4000
Torque Ft. Lbs. @ RPM255 @ 2400

GENERAL SPECIFICATIONS

CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS SPECIFICATIONS

ApplicationIn. (mm)
Crankshaft
End Play.001-.007 (.03-.17)
Runout (Maximum).001 (.03)
Main Bearings
Journal Diameter
Journal No. 12.4484-2.4493 (62.198-62.212)
Journals No. 2, 3 & 42.4481-2.4490 (62.182-62.205)
Journal No. 52.4481-2.4488 (62.182-62.200)
Journal Out-Of-Round (Maximum).001 (.03)
Journal Taper (Maximum).001 (.03)
Oil Clearance
Journal No. 1.0008-.0020 (.020-.051)
Journals No. 2, 3 & 4.0010-.0025 (.025-.064)
Journal No. 5.0017-.0035 (.043-.089)
Connecting Rod Bearings
Journal Diameter2.0893-2.0998 (53.068-53.335)
Journal Out-Of-Round (Maximum).001 (.03)
Journal Taper (Maximum).001 (.03)
Oil Clearance.0013-.0035 (.033-.089)

CRANKSHAFT, MAIN & CONNECTING ROD BEARINGS SPECS

CONNECTING RODS SPECIFICATIONS

ApplicationIn. (mm)
Maximum Bend(1)
Maximum Twist(1)
Side Play.006-.014 (.15-.36)
(1) Replace rod if any bend or twist exists.
(1)Replace rod if any bend or twist exists.

CONNECTING RODS SPECIFICATIONS

PISTONS, PINS & RINGS SPECIFICATIONS

ApplicationIn. (mm)
Piston Clearance.0010-.0027 (.025-.069)
Pins
Diameter.9270-.9271 (23.546-23.548)
Piston Fit.0003-.0010 (.076-.025)
Rod Fit (Press).0008-.0016 (.020-.041)
Rings
No. 1
End Gap.010-.020 (.25-.51)
Side Clearance.0012-.0032 (.030-.081)
No. 2
End Gap.018-.026 (.46-.66)
Side Clearance.0012-.0032 (.030-.081)
No. 3 (Oil)
End Gap
Except LT1.015-.055 (.38-1.40)
LT1 (VIN "P").010-.030 (.25-.76)
Side Clearance.002-.007 (.05-.18)

PISTONS, PINS & RINGS SPECIFICATIONS

CYLINDER BLOCK SPECIFICATIONS

ApplicationIn. (mm)
Cylinder Bore Diameter3.738 (94.95)
Maximum Taper.001 (.03)
Maximum Out-Of-Round.002 (.05)

CYLINDER BLOCK SPECIFICATIONS

VALVES & VALVE SPRINGS SPECIFICATIONS

ApplicationIn. (mm)
Valves
Face Angle45°
Minimum Margin.031" (.80 mm)
Valve Springs
Installed Height
LT1 (VIN "P")1.78" (45.2 mm)
Except LT11.70" (43.2 mm)
Pressure (1)
Valve Closed
LT1 (VIN "P")81-89 @ 1.78 (36-40 @ 45.2)
Except LT176-84 @ 1.70 (34-37 @ 43.2)
Valve Open
LT1 (VIN "P")252-272 @ 1.31 (114-123 @ 33.3)
Except LT1194-206 @ 1.25 (88-93 @ 31.8)
(1) Lbs. @ In. (Kg @ mm).
(1)Lbs. @ In. (Kg @ mm).

VALVES & VALVE SPRINGS SPECIFICATIONS

CYLINDER HEAD SPECIFICATIONS

ApplicationIn. (mm)
Valve Seats
Intake Valve
Seat Angle46°
Seat Width.035-.060" (.89-1.52 mm)
Exhaust Valve
Seat Angle46°
Seat Width.060-.094" (1.52-2.39 mm)
Valve Guides Stem-To-Guide Oil Clearance.0011-.0027" (.028-.069 mm)

CYLINDER HEAD SPECIFICATIONS

CAMSHAFT SPECIFICATIONS

ApplicationIn. (mm)
End Play.004-.012 (.10-.30)
Journal Diameter1.868-1.869 (47.45-47.47)
Lobe Lift
Exhaust.257 (6.53)
Intake.233 (5.92)

CAMSHAFT SPECIFICATIONS