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ENGINES

MECHANICAL INFORMATION

3A-0 - MECHANICAL INFORMATION 90-806535940 893

Table of ContentsPage

Engine Identification 3A-1. . . . . . . . . . . . . . . . . . . . . . 4 Cylinder 3A-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . V-6 3A-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V-8 3A-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.0L and 3.0LX 3A-2. . . . . . . . . . . . . . . . . . . . . . . . . . Tools/Lubricants/Sealants 3A-2. . . . . . . . . . . . . . . Torque Specifications 3A-3. . . . . . . . . . . . . . . . . . Engine Specifications 3A-4. . . . . . . . . . . . . . . . . .

4.3L and 4.3LX 3A-7. . . . . . . . . . . . . . . . . . . . . . . . . . Tools/Lubricants/Sealants 3A-7. . . . . . . . . . . . . . . Torque Specifications 3A-8. . . . . . . . . . . . . . . . . . Engine Specification 3A-10. . . . . . . . . . . . . . . . . .

305/5.0L/350/5.7L 3A-15. . . . . . . . . . . . . . . . . . . . . . . Tools/Lubricants/Sealants 3A-15. . . . . . . . . . . . . . Torque Specifications 3A-16. . . . . . . . . . . . . . . . . Engine Specifications 3A-18. . . . . . . . . . . . . . . . .

454 CID (7.4L) and 502 CID (8.2L) 3A-23. . . . . . . . Tool/Lubricants/Sealants 3A-23. . . . . . . . . . . . . . . Torque Specifications 3A-24. . . . . . . . . . . . . . . . . 454/7.4L/502/8.2L Engine Specifications 3A-26.

Cylinder Head Torque Sequences 3A-32. . . . . . . . . 3.0L/3.0LX 3A-32. . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3L/4.3LX 3A-32. . . . . . . . . . . . . . . . . . . . . . . . . . . 305/5.0L/350/5.7L 3A-32. . . . . . . . . . . . . . . . . . . . 7.4l/454/8.2L/502 3A-32. . . . . . . . . . . . . . . . . . . . .

Intake Manifold Torque Sequence 3A-33. . . . . . . . . 4.3L/4.3LX 3A-33. . . . . . . . . . . . . . . . . . . . . . . . . . . 350/5.7L 3A-33. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 454/7.4L/502/8.2L 3A-33. . . . . . . . . . . . . . . . . . . .

Dipstick Specifications 3A-34. . . . . . . . . . . . . . . . . . . 4.3L/4.3LX 3A-34. . . . . . . . . . . . . . . . . . . . . . . . . . . 350/5.7L 3A-35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 454/7.4L/502/8.2L 3A-36. . . . . . . . . . . . . . . . . . . .

Diagrams for Tool Usage 3A-37. . . . . . . . . . . . . . . . . Valve Spring Removal With Head On 3A-37. . . . Valve Spring Removal With Head Off 3A-37. . . . Valve Guide Cleaner 3A-37. . . . . . . . . . . . . . . . . . Checking For Cylinder Head Flatness 3A-37. . . Rocker Arm Stud Replacement 3A-38. . . . . . . . . Checking Valve Spring Height 3A-39. . . . . . . . . . Checking Valve Spring Pressure 3A-39. . . . . . . . Checking For Valve Guide Wear 3A-40. . . . . . . . Valve Guide Bore Repair 3A-40. . . . . . . . . . . . . . Removing The Torsional Damper 3A-41. . . . . . . Installing Oil Seal In Cover With Cover Still On Engine 3A-41. . . . . . . . . . . . . . . . . . . . . . . Installing New Seal With Cover Removed 3A-41. . . . . . . . . . . . . . . . . . . . . . . . . . . Flywheel Runout 3A-42. . . . . . . . . . . . . . . . . . . . . Rear Main Seal Removal 3A-42. . . . . . . . . . . . . . Using Rear Main Seal Installer. 3A-42. . . . . . . . . Checking Clearance On Crankshaft Journals 3A-43. . . . . . . . . . . . . . . . . . . . . . . . . . . . Checking Clearance On Rod Journals 3A-43. . . Measuring Crankshaft End Play 3A-43. . . . . . . . Measuring Piston Ring Gap 3A-43. . . . . . . . . . . . Position Of Piston Rings On Pistons 3A-44. . . . Piston Orientation 3A-44. . . . . . . . . . . . . . . . . . . . V-6 and V-8 Piston Installation 3A-45. . . . . . . . . . Cylinder Wall Inspection And Measurement 3A-45. . . . . . . . . . . . . . . . . . . . . . . . Checking Deck Surface 3A-46. . . . . . . . . . . . . . . Camshaft Gear And Sprocket Installer 3A-47. . . Checking Timing Chain Deflection 3A-47. . . . . . Alignment Of Timing Marks 3A-47. . . . . . . . . . . . Measuring Lobe Lift 3A-47. . . . . . . . . . . . . . . . . . .

3A - MECHANICAL INFORMATION

MECHANICAL INFORMATION - 3A-190-8065359840 893

Engine Identification

4 Cylinder

73584

a

a Location of G.M. Engine Code

MCM (Stern Drive) Code Rotation

3.0L RM,RJLH3.0LX RN,RK LH

V-6

72312a - Location of GM Engine Code

a

MCM(Stern Drive)

Code Rotation

4.3L Alpha LGLH4.3LX Alpha LH LH

V-8

72312a - Location of GM Engine Code

a


5.0L Alpha ZC

5.0LX Alpha ZD

5.0L Bravo ZC LH5.7L Alpha MB

5.7L Bravo CD,MD

350Magnum Alpha(See Note)

CD,MD

MIE (Inboard) Code Rotation

5 7LNN LH

5.7L NR RH

5 7L Competition SkiMB LH

5.7L Competition Ski MR RH

350 Magnum TournamentSki (See Note)

CD,MD LH

Note; Engines with roller lifters and steel camshaft


7.4L XWLH454 Magnum XA LH

502Magnum EFI HJ

MIE (Inboard) Code Rotation

7.4L XYLH8.2L FH LH

454 EFI Ski UA


3.0L and 3.0LXTools/Lubricants/Sealants

MERCURY MARINE SPECIAL TOOLS

91-24697 Piston Ring Expander

91-63209 Torch Lamp

KENT MOORE SPECIAL TOOLS

J5892 Valve Spring Compressor (Head on)

J8062 Valve Spring Compressor (Head off)

J23738-A Valve Stem Seal Tester

J8101 Valve Guide Cleaner

J8814 Valve Guide Reamer (Standard)

J5830-02 Valve Guide Reamer (.015 in. oversize)

J5802-01 Rocker Arm Stud Remover

J6880 Rocker Arm Stud Installer

J5715 Stud Bore Reamer (.003 in. oversize)


J8089 Carbon Remover Brush

J5910-04 Piston Support Tool

J24086-B Piston Pin Tool

J3936-03 Piston Ring Groove Cleaner

J8037 Piston Ring Compressor

J5239 Connecting Rod Guide Tool (3/8 -24)

J8087 Cylinder Bore Checker

J8369 Oil Pump Suction Pipe Installer

J23042-B Timing Cover Seal Aligner

J8520 Cam Lobe Lift Indicator

J6098-01 Camshaft Bearing Installer/Remover Tool

J9534-01 Distributor Shaft Lower Bearing Installer/Remover

J6978-E Pulley Hub Puller

J5590 Pulley Hub Installer

J24420 Universal Torsional Damper Remover

LUBRICANTS/SEALANTS

92-34227--1 Quicksilver Perfect Seal

92-86154A1 Quicksilver 2-C-4 Marine Lubricant

92–91601-1 Quicksilver RTV Sealer


Torque Specifications

Fastener Location Lb. Ft. (N ⋅m) Lb. In. (N ⋅m)

Camshaft Sprocket Bolts 80 (9)

Connecting Rod Cap Nuts 45 (61)

Cylinder Head Bolts 90 (122) See Note 1

Distributor Clamp 20 (27)

Engine Coupler to Flywheel 35 (47)

Flywheel Housing to Block 21 (28)

Flywheel to Crankshaft Bolts 65 (88)

Front Cover Bolts 30 (3.4)

Front Mount to Block 21 (28)

Main Bearing Cap Bolts 65 (88)

Manifold to Head 23 (31) See Note 2

Oil Pan Bolts-Crankcase 80 (9)

Oil Pan Bolts -to Front Cover 45 (5)

Oil Pan Studs to Oil Seal Retaineror Crankcase

15 (1.7)

Oil Pump Cover 72 (8)

Oil Pump to Block 120 (14)

Oil Pump Pickup 60 (7)

Rocker Arm Cover and Bolts 40 (4.5)

Rear Crankshaft Oil Seal RetainerNuts

135 (15)

Spark Plugs 22 (30)

Starter Motor to Block 37 (50)

Timing Gear Cover 72 (8)

Torsional Damper Bolt 50 (68)

Water Pump to Block 15 (20)

Note 1: Retorque after first 20 hours of operation.

Note 2: Retorque after first start up.


Engine Specifications

Model 3.0L/3.0LX

Displacement 181 CID (3.0L)

CYLINDER BORE

Diameter 3.9995-4.0025(101.588-101.790)

Out of RoundProduction .0005(0.012) Max

Out of Round Service .002(0.05) Max

Taper ProductionThrust Side .0005(0.012) Max

Taper Production Relief Side .0005(0.012) Max

Service .001(0.02) Max

PISTON CLEARANCE

Production .0025-.0035(0.064-0.088) Max


PISTON RING: COMPRESSION

Groove Clearance ProductionTop

0012 0029(0 030 0 073)Groove Clearance Production 2nd .0012-.0029(0.030-0.073)


Gap ProductionTop

010 020(0 254 0 762)Gap Production 2nd .010-.020(0.254-0.762)


PISTON RING: OIL

GrooveClearance

Production .001-.006(0.026-0.152)Clearance Service Limit .007(0.17) Max

GapProduction .010-.030(0.254-0.762) Max

Gap Service Limit .040(1.01) Max

PISTON PIN

Diameter .9270-.9271(23.546-23.550)

ClearanceProduction .0003–.0006(0.008-0.016)

Clearance Service Limit .001(0.02) Max

Fit in Rod .0008-.0019(0.020-0.050) Interference

UNIT OF MEASUREMENTin. (mm)


CRANKSHAFT

Diameter 2.2979-2.294(58.367-58.404)

TaperProduction .0002(0.005) Max

Main JournalTaper Service .001(0.02) Max



Production No.1-No.4 .001-.0024(0.025-0.060)

Main BearingService No.5 .0016-.0035(0.041-0.088)

Main BearingClearance Production No.1-No.4 .001-.0025(0.03-0.06)

Service No.5 .002-.0035(0.05-0.08)

Crankshaft End Play .002-.006(0.05-0.15)

Diameter 2.09980-20995(53.289-53.327)

TaperProduction .0003(0.007) Max

CrankpinTaper Service .001(0.02) Maxp



Rod BearingClearance

Production .0017-.0027(0.044-0.0686)Clearance Service

Rod Size Clearance .006-.017(0.153-0.4318) Max

CAMSHAFT

Lobe Lift (Max )Intake .2529(6.425)

Lobe Lift (Max.) Exhaust .2529(6.425)

Journal Diameter 1.8677-18697(47.440-47.490)

Camshaft End Play .003-.008(0.08-0.2032) Max

CYLINDER HEAD

Gasket Surface Flatness .003-.008in any 6 in.(152)or .007(0.15) Overall Max


VALVE SYSTEM

Lifter Hydraulic

Rocker Arm Ratio 1.75 to 1

Collapsed Tappet Gap Half to 1 Turn Down from Zero Lash

Face AngleIntake 45°

Face Angle Exhaust 45°Seat Angle (Intake & Exhaust) 46°

Seat Runout (Intake & Exhaust) .002(0.05) Max

Seat WidthIntake 1/16 (.0625)in. (1.16 mm)

Seat Width Exhaust 1/16-5/64 [.0625-.07812] in. (1.6-2.0 mm)

ProductionIntake .0010-.0027(0.025-0.069)

StemProduction Exhaust .0007-.0027(0.018-0.069)

StemClearance

ServiceIntake .003(0.09) Max

Service Exhaust .004(0.11) Max

Free Length 2-1/16(52)

PressureValve Closed 100-110 lb. (136-149 N) at 1-19/32 in. (41 mm)

SpringPressure Valve Open 208-220 lb. (282-300 N) at 1-7/32 in. (31 mm)p gInstalledHeight±

Intake(1/32)1.6562(42)Height±

.031(8) Exhaust(1/32)1.6562(42)

Internal Damper None


4.3L and 4.3LXTools/Lubricants/Sealants



91-35547 Engine Coupler Wrench

92-823089 Quicksilver Loctite A

92-34227 Quicksilver Perfect Seal

92-91601-1 Quicksilver RTV Sealer

Obtain Locally General Motors Cam and Lifter Prelude

SNAP-ON SPECIAL TOOLS

TA360 Torque Angle Gauge (Degree Wheel Torquing)

KENT-MOORE SPECIAL TOOLS

J5982 Valve Spring Compressor (Head On)

J8062 Valve Spring Compressor (Head Off)

J8056 Valve Spring Tester


J5830-2 Valve Guide Reamer

J7049 Valve Guide Reamer


J24086-B Piston Pin Remover Kit



J5239 Connecting Rod Bolt Guide Set (3/8-24)


J6098-01 Camshaft Bearing Remover and Installer Set

J8520-1 Ball Socket Adapter Tool Kit (Lift Indicator)

J23523-E Torsional Damper Remover and Installer

J35468 Crankcase Front Cover Seal Installer

J5825-A Crankcase Gear and Sprocket Puller

J5590 Crankcase Gear and Sprocket Installer

J23590 Air Adapter

J8080 Main Bearing Remover and Installer

J26817-A Rear Main Seal Installer

J26941 Balance Shaft Rear Bearing Remover

J38834 Balance Shaft Bearing Remover and Installer



Fastener Location Lb. Ft. (N.m) Lb. In. (N.m)

Alternator Brace to Alternator 192(28)

Alternator Brace to Engine 30(41)

Alternator to Mounting Bracket 35(48)

Alternator Mounting Bracket 30(41)

Balance Shaft Drive Gear Retaining Stud 120(16)

Balance Shaft Driven Gear Bolt (Torque Plus 35°) 15(20)

Balance Shaft Thrust Plate 120(14)

Camshaft Sprocket 20(27)

Camshaft Thrust Plate 106(12)

Carburetor 132(15)

Connecting Rod Cap Nuts (Torque Plus 60°) 20(27)

Coupler/Flywheel(MCM) 35(48)

Crankcase Front Cover 124(14)

Crankshaft Pulley Bolt (Cast Aluminum) 40(54)

Cylinder Head 65(88)

Distributor Hold Down 25(34)

Exhaust Manifold 20(27)

Flywheel 75(100)

Flywheel Housing to Block 30(41)

Flywheel Housing Cover 80(9)

Front Mount Bracket 30(41)

Fuel Filter Bracket Bolt 25(34)

Fuel Pump Bracket Bolt 25(34)

Fuel Pump Inlet Fitting (Large Diameter See Note) 96(10.8)

Fuel Pump Inlet Fitting (Small Diameter See Note) 84(9.5)

Intake Manifold 35(48)

Main Bearing Cap 75(100)

Oil Filter Adapter Bolts 15(20)

Oil Pan Drain Plug 15(20)

Note : Hold Fuel Pump using wrench on flat surface at outlet before tightening brass fitting



OIl Pan Screw (1/4-20) 80(9)

Oil Pan Nuts (5/16-20) 165(19)

OIl Pump 65(68)

Oil Pump Cover 80(9)

Power Steering Pump Brace to Block 30(41)

Power Steering Pump Bracket 30(41)

Rear Crankshaft Oil Seal Retainer Screws and Nuts 133(15)

Rear Mount (MCM) 40(54)

Rocker Arm Cover 50(5.5)

Rocker Arm Nuts 20(27)

Roller Lifter Restrictor Plate 12(16) 144(16)

Seawater Pump Brace (if equipped) 30(41)

Seawater Pump Bracket (if equipped) 30(41)

Spark Plugs 15(20) 180(20)

Starter Motor 50(68)

Thermostat Housing 30(41)

Torsional Damper 40(54)

Water Circulating Pump 30(41)

Water Temperature Sender 20(27)


Engine Specification

Unit of Measurement in. (mm)

Engine Model 4.3L/43LX

Displacement 262 CID (4.3 Litre)

Bore 4.00(101.6)

Stoke 3.48(88.39)

Compression Ratio 9.05:1

Heads Cast Iron

Intake Manifold Cast Iron

Block Cast Iron (2 Bolt Main Bearing Caps)

Rods Forged Steel

Pistons Cast Aluminum

Crankshaft Cast Iron

Camshaft Steel

72976

LH ROTATIONFRONT

Firing Order1-6-5-4-3-2


Model 4.3L/4.3LX

Displacement 262 CID (4.3L)

CYLINDER BORE

Diameter 4.000-4.001(101.617-101.643)





Service .001(0.02) Over Production

PISTON CLEARANCE

Production .0007-.0017(0.017-0.043) Max



ProductionTop

.0012-.0032(0.030-0.081)Groove Clearance

Production2nd

.0012-.0032(0.030-0.081)

Service High Limit Production+.001(0.025)

Gap ProductionTop .010-.020(0.254-0.508)

Gap Production 2nd .010-.025(.0254-.0635)

Service High Limit Production + .010(0.25)

PISTON RING: OIL

GrooveClearance

Production .002-.007(0.051-0.177)Clearance Service High Limit Production + .001(0.025)

GapProduction .015-.055(0.381-1.397)

Gap Service Limit High Limit Production + .010(0.254)

PISTON PIN

Diameter .9270-.9273(23.546-23.553)





CRANKSHAFT

DiameterNo.1 2.4484-2.4493(62.198-62.212)

Diameter No. 2, 3 2.4481-2.4490(62.181-62.204)

M iNo.4 2.4479-2.4488(62.176-62.199)

Main Journal Taper

Production .0002(0.005) MaxJournal Taper Service .001(0.02) Max



ProductionNo.1 .0008-.0020(0.020-0.050)

Production No.2, 3 .0011-.0023(0.027-0.058)

Main BearingCl

No.4 .0017-.0032(0.043-0.081)gClearance

ServiceNo.1 .0010-.0015(0.03)

Service No.2, 3 .0010-.0025(0.03-0.06)

No.4 .0025-.0035(0.07-0.08)


Diameter 2.2487-2.2497(57.117-57.142)

Connecting Rod TaperProduction .0005(0.021) Max

Connecting RodJournal

Taper Service .001(0.02) Max



Rod Bearing ClearanceProduction .0013-.0035(0.033-0.088)

Rod Bearing Clearance Service .003(0.07) Max

Rod Side Clearance .006–.014(0.15-0.35)

Crankshaft Runout .0015(0.038) Max


VALVE SYSTEM

Lifter Hydraulic


Valve LiftIntake .394(10.00)

Valve Lift Exhaust .404(10.26)

Valve Lash (Intake and Exhaust) Fixed Lash

Face Angle (Intake & Exhaust) 45°Seat Angle (Intake & Exhaust) 46°


Seat WidthIntake 1/32-1/16 [.03125-.0625] in. (0.79-1.58 mm)



Stem Clear-Production Exhaust .0010-.0027(0.025-0.069)

Stem Clear-ance



Stem DiameterIntake .341(8.66)

Stem Diameter Exhaust .372(9.45)

Valve Margin Intake and Exhaust 1/32 (0.79)

VALVE SPRING

Free Length 2.03(51.6)

Valve Spring PressureValve Closed 76-84 Lb. (338-374 N) at1.785 [1-45/64](43.16)

Valve Spring Pressure Valve Open 194-204 Lb. (863-916 N) at 1.250[1-1/4](31.75)

Installed Height 1.70 [1-45/64](47.24)

Damper Free Length 1.86 [1-55/64](47)

Approximate Number of Coils 4

NOTE: Test spring pressure with damper removed


CAMSHAFT AND DRIVE

Lobe Lift ±002(0 051)

Intake .269(6.89).002(0.051) Exhaust .273(6.93)

Journal Diameter 1.8682-1.8692(47.452-47.478)

Journal Out of Round .001(0.025) Max

Camshaft Runout .002(0.051) Max

Camshaft End Play .004-.012(0.11-0.30)

Timing Chain Deflection .375(9.5) from taut position [total .75 (19)]

FLYWHEEL

Runout .008(0.203) Max

CYLINDER HEAD

Gasket Surface Flatness .004(0.10) Overall Maximum

BALANCE SHAFT

Front Bearing Journal 1.1812-1.1815(30.002-30.010)

Rear Bearing Journal 1.4209-1.4215(36.091-36.106)

Rear Bearing Inside Diameter Assembled Production 1.501-1.503(37.525-37.575)

Rear Bearing Outside Diameter Production 1.875-1.876(46.875-46.900)

Rear Cylinder Block Housing Bore Production 1.873-1.874(46.825-46.850)


305/5.0L/350/5.7LTools/Lubricants/Sealants




91-66273 Rocker Stopper

92-32609-1 Quicksilver Loctite


92-42649A1 Quicksilver Needle Bearing Assembly Grease


Obtain Locally General Motors Cam and Lifter Prelube or Equivalent






J7049 Valve Guide Reamer (Standard)

J5830-02 Valve Guide Reamer (.015 in. oversize)

J5802-01 Rocker Arm Stud Remover

J6880 Rocker Arm Stud Installer









J6098-01 Camshaft Bearing Installer/Remover Tool

J8520-1 Ball Socket Adapter



J5825-A Crankshaft Gear and Sprocket Puller

J5590 Crankshaft Gear and Sprocket Installer

J23590 Air Adapter




J26817-A Rear Main Seal Installer


Fastener Location Lb. Ft. (N.m) Lb. In. (N.m)





Camshaft Sprocket Gear 18(24) 216(24)

Carburetor 132(15)

Connecting Rod Cap Nuts 45(61)


Crankshaft Pulley 35(48)




Filter Adapter (5/16-18) 20(27)

Flywheel 75(100)

Flywheel Drive Plate (MIE) 35(48)




Fuel Pump 25(34)

Intake Manifold 35(48)


Oil Baffle Nuts 25(34)

Oil Filter Adapter Bolts 15(20)


Oil Pan Screw (1/4-20) 80(9)

Oil Pan Nuts (5/16-18) 165(19)

Oil Pump 65(88)




Rear Crankshaft Oil Seal Retainer Screws and Nuts 133(15)


Rear Mount (MIE) 50(68)


Fastener Location Lb. Ft. (N ⋅m) Lb. In. (M ⋅n)

Remote Oil Connector (1/2 in. x 13) 25(34)

Remote Oil Filter Adapter Nut/Fitting 20(27)

Spark Plugs 15(20)



Timing Chain or Gear Cover 100(11)


Transmission To Housing 50(68)



Rocker Arm Cover 90(10)

Roller Lifter Restrictor Retainer Plate 12(16)

Seawater Pump Brace 30(41)

Seawater Pump Bracket 30(41)


Engine Specifications

Unit Of Measurement In. (mm)

EngineModel

MCM5.0L

MCM5.0LX

MCM5.0L

Bravo

MCM5.7L

Alpha

MCM5.7L

Bravo

MCM350

MagnumAlpha

MIE5.7L

MIE5.7L

Comp.Ski

MIEMagnum

Tour.Ski

Displace-ment

305 CID (5.0 Litre) 350 CID (5.7 Litre)

Bore 3.74(95) 4.00(101.6)

Stroke 3.48(88.4) 3.48(88.4)

Com-pression

Ratio9.1:1

Heads Cast Iron

IntakeManifold

Cast Iron (Magnums-High Rise-See Note 2)


Rods Forged Steel

Crank-shaft

Cast Iron

Pistons Cast Aluminum

Cam-shaft

Cast Iron Steel (See Note 1)

Cast Iron Steel(Note 1)

FuelPumpPushRod

SteelCast Iron

(See Note 1)

Steel Cast Iron (See

Note 1)

NOTE1: Engine with roller lifters and steel camshaft

NOTE 2: Includes- 350 Magnum Alpha,5.7L Bravo and 350Magnum Tournament Ski

7200972008

ALH ROTATION

FRONT

BRH ROTATION

FRONT

Firing Order1-8-4-3-6-5-7-2

Firing Order1-2-7-5-6-3-4-8


Model 5.0L/5.0LX 5.7L/350 Magnum

Displacement 305 CID (5.0L) 350 CID (5.7L)

CYLINDER BORE

Diameter 3.7350-3.7385(94.8690-94.9579)

3.9995-4.0025(101.5873-101.6635)






PISTON CLEARANCE

Production .0007-.0017(0.017-0.043) Max



ProductionTop

0012 0032(0 030 0 081)Groove Clearance

Production 2nd .0012-.0032(0.030-0.081)Groove Clearance


Gap ProductionTop .010-.020(0.254-0.508)

010 025( 0254 0635)Gap Production 2nd .010-.025(.0254-.0635)


PISTON RING: OIL

GrooveClearance

Production .002-.007(0.051-0.177)Clearance Service High Limit Production + .001(0.025)

GapProduction .015-.055(0.381-1.397)

Gap Service Limit High Limit Production + .010(0.254)

PISTON PIN

Diameter .9269-.9271(23.545-23.553)





CRANKSHAFT

DiameterNo.1 2.4484-2.4493(62.198-62.212)

Diameter No. 2, 3 2.4481-2.4490(62.181-62.204)

M iNo.4 2.4479-2.4488(62.176-62.199)

Main Journal Taper

Production .0002(0.005) MaxJournal Taper Service .001(0.02) Max



ProductionNo.1 .0008-.0020(0.020-0.050)

Production No.2, 3 .0011-.0023(0.027-0.058)

Main BearingCl

No.4 .0017-.0032(0.043-0.081)gClearance

ServiceNo.1 .0010-.0015(0.03)

Service No.2, 3 .0010-.0025(0.03-0.06)

No.4 .0025-.0035(0.07-0.08)


Diameter 2.0988-2.0998(57.117–57.142)








Rod Side Clearance .006–.014(0.15-0.35)

Crankshaft Runout .0015(0.0381) Max


VALVE SYSTEM

Engine 5.0L/5.7L 5.7L/350 Magnum

Lifter Type Flat HydraulicFlat Hydraulic

Lifter Type Flat Hydraulic Roller Hydraulic




Valve Lash (Intake and Exhaust) 1 Turn Down from Zero Lash

Face AngleIntake 45°

Face Angle Exhaust 45°Seat Angle (Intake & Exhaust) 46°


Seat WidthIntake 1/32-1/16 [.03215-.0625] in. (0.79-1.58 mm)




Stem Clear-ance





Valve Margin Intake and Exhaust .0312(0.79)

VALVE SPRING

Free Length 2.03(51.6) (See Note 1)

Valve Spring24 48347

Pressure(NOTE 1)

Valve Closed 76-84 Lb. Ft.(103-113 N⋅m) at1.785(43.16)24-48347Lavender

(NOTE 1) Valve Open 194-204 Lb. Ft. (263-279 N⋅m) at 1.250(31.75)LavenderStripe Installed

HeightIntake 1.7[1-45/64](43)

DamperFree Length 1.86[1-55/64](47)

Damper Approximate Number of Coils 4

NOTE 1: Test spring pressure with damper removed


CAMSHAFT AND DRIVE

Engine 5.0L/5.0LX 5.7L/350 Magnum

Lobe Lift ± 002(0 051)Exhaust

263(6 680).263(6.680)

Lobe Lift ± .002(0.051) Intake .263(6.680) .287(7.29) (See Note)

Duration at .050 In.(1.27mm)Cam Lift

Exhaust0269(6 833)

.269(6.833)Cam Lift Intake 0269(6.833) .300(7.62) (See Note)


Journal Out Of Round .001(0.025) Max


Timing Chain Deflection[LH (Standard) Rotation Engine Only]

.375(9.5) from taut position [total .75(19)]

Camshaft Timing Gear Runout [RH (Opposite) Rotation Engine Only]

.004(0.012) Max

Crankshaft Timing Gear Runout [RH (Opposite)Rotation Engine Only]

.003(0.076) Max

Camshaft to Crankshaft Timing Gear Back-lash[RH (Opposite)Rotation Engine Only]

.004-.006(0.102-0.152) New Gears.004-.008(0.102-0.203) Used Gears

Note : Engines with roller lifters and steel camshaft

FLYWHEEL


CYLINDER HEAD

Gasket Surface Flatness .004(0.10) Overall Maximum


454 CID (7.4L) and 502 CID (8.2L)Tool/Lubricants/Sealants




92-32609-1 Quicksilver Loctite A



Obtain Locally General Motors Cam and Lifter Prelube or Equivalent











J35228 Connecting Rod Guide Tool (7/16-20)


J8520 Lift Indicator Tool



J24420-B Crankshaft Gear and Sprocket Puller

J20158-20 Crankshaft Gear and Sprocket Installer

J23590 Air Adapter (Cylinder Inflator)


J38841 Rear Main Seal Installer








Camshaft Sprocket Gear 18(24) 216(24)

Carburetor 132(15)

Connecting Rod Caps (3/8-24) 50(68)

(7/16-20) 73(99)


Crankcase Front Cover 120(14)

Crankshaft Pulley 35(48)




Exhaust Manifold Elbow 30(41)

Filter Adapter (5/16-18) 20(27)

Flywheel 75(100)

Flywheel Drive Plate (MIE) 35(48)




Fuel Pump 25(34)

Intake Manifold 35(48)(See Note)


Oil Baffle Nuts 25(34)

Oil Filter Adapter Nuts 40(54)

Oil Pan Bolts (5/16-18) 80(9)


Oil Pump 70(95)





Rear Mount (MIE) 50(68)

Remote Oil Connector (1/2 in. x 13) 25(34)

Remote Oil Filter Adapter Nut/Fitting 20(27)

Rocker Arm Bolts 45(61)

Rocker Arm Cover 90(10)


Fastener Location Lb. Ft. (N ⋅m)

Seawater Pump Brace 30(41)

Seawater Pump Bracket 30(41)

Spark Plugs 15(20)




Transmission To Housing 50(68)




454/7.4L/502/8.2L Engine Specifications

Unit of Measurement In. (mm)

Engine Model MCM7.4L

MIE7.4L

MCM7.4L

BravoThree

MCM 454Mag-

num/454Magnum

EFI

MIE 454EFI SKI

MIE8.2L, MCM 502 MagnumMCM 502 Magnum EFI

Displacement 454 CID(7.4L) 502 CID(8.2L)

Bore 4.25 (108) 4.46 (113.28)

Stroke 4.00 (101.6)

Compression Ratio 8.0:1 8.6:1 8.75:1

Heads Cast Iron (Oval Port) Cast Iron (Rectangular Port)

Intake Manifold Cast Iron Aluminum with Brass Inserts-High Rise (See Note)


Rods Forged Steel

Pistons Cast Aluminum Forged Aluminum

Crankshaft Cast Steel Forged Steel

Camshaft Cast Iron

NOTE: The 454/502 EFI Magnum is equipped with a cast aluminum intake manifold

Engine7.4L

Bravo OneBravo Two

7.4L BravoThree

454 Magnum/454 Magnum EFI/

454 EFI Ski

502 Magnum EFI/8.2L

CYLINDER BORE

Diameter 4.2500-4.2507(107.950-107.967)

4.2500-4.2507(107.950-107.967)

4.2451-4.2525(107.826-108.013)

4.4655-4.4662(113.423-113.441)

Out of Round Produc-tion

.001(0.025) Max


Taper Pro-duction

ThrustSide

.0005(0.0127) Max

duction ReliefSide

.001(0.0254) Max


PISTON

ClearanceProduction .0030-.0042

(0.0762-0.1066).0025-.0037

(0.0635-0.0939).0040-.0057

(0.1016-0.1447)

Service .005(0.12) Max .0075(0.15) Max .0065(0.16) Max


Engine7.4L

Bravo OneBravo Two

7.4L BravoThree

454 Magnum/454 Magnum EFI/

454 EFI Ski

502 Magnum EFI/8.2L

PISTON RING

Co

GrooveSide

Pro-duction

Top

.0012-.0029(0.0305-0.0737)

.0017-.0032(0.044-0.081)

.0017-.0032(0.044-0.081)

ompr

Side Clear-ance

2nd

.0012-.0029(0.0305-0.0737)

.0017-.0032(0.044-0.081)

.0017-.0032(0.044-0.081)

re Service High Production Limit +.010(0.02) Maxssio Gap

Pro-duction

Top

.010-.018(0.25-0.46)

.011-.021(0.28-0.53)

on

Gap 2nd

.016-.024(0.41-0.61)

.016-.026(0.41-0.66)

Service High Limit Production + .010(0.25) Max

GrooveSide

Produc-tion

.0050-.0065(0.127-0.165)

Oil

SideClear-ance

ServiceHigh Limit Production + .001(0.25) High Limit

Production.005(0.12) Max

Oil

Gap

Produc-tion

.010-.030(0.254-0.762)

.020-.035(0.508-0.889)

.010-.030(0.254-0.76)

Gap

ServiceHigh Limit Production + .001(0.25) High Limit

Production.005(0.12) Max

Engine 7.4L454 Magnum/

7.4L BravoThree/454 EFI

Ski/454 EFI Mag-num

502 Magnum502 Magnum EFI

8.2L

PISTON PIN

Diameter .9895-.9897(25.132-25.1371)

.9895-.9898(25.134-24.140)

Clearance In PinProduc-

tion.0002-.0007

(0.0050-0.0177).00025-.00035

(0.0064-0.0088)


Fit In Rod.0021-.0031

(0.0533-0.0787)Interference

.0008-.0016(0.021-0.040)Interference


Engine7.4L/454 Mag-num/454 EFISki/454 EFI

Magnum

502 Magnum/502 Magnum EFI8.2.L

CRANKSHAFT

Diameter No.1,2,3,4,5 2.7482-2.7489(69.8042-69.8220)

Main TaperProduction .0002(0.005) Max

Main Journal




ProductionNo.1,2,3,4 .0007-.0030(0.043-0.076)

Production No.5 .0025-.0038(0.063-0.096)

Main BearingClearance

Service

No.1 .001-.003(0.03-0.07)

.0010-.0015(0.0254-0.0381)

Service No.2,3,4 .001-.003(0.03-0.07)

.0010-.0025(0.0254-0.0635)

No.5 .0025-.0040(55.8546-55.8698)


Diameter 2.1990-2.1996(57.8546–57.8698)








Rod Side Clearance .013-.023(0.35-0.58)

Crankshaft Runout @ No.3 main Bearing .0015(0.038)Max

.0035(0.088) Max


Engine Model 7.4L/7.4L Bravo

Three

454 Mag-num/454 EFISKI/454 EFI

Magnum

502 MagnumEFI/8.2L

VALVE SYSTEM

Lifter Roller Hydraulic




Valve Lash (Intake and Exhaust) Fixed Lash

Face Angle (Intake & Exhaust) 45°Seat Angle (Intake & Exhaust) 46°


Seat WidthIntake 1/32-1/16 [.03125 .0625] in. (0.79-1.58 mm)

Seat Width Exhaust 1/16-3/32 [.0625-.09375] in.(1.58-2.38 mm)



Stem Clear-ance

ServiceIntake .001(0.02) .003(0.07) .0037(0.09)

Service Exhaust .002(0.05) .004(0.10) .0049(0.12)



Valve Margin Intake and Exhaust .0312(0.79)


Engine Model 7.4L454 Magnum/502

Magnum/502 Mag-numEFI/EFI 8.2L

VALVE SPRING

Free Length 2.12(53.9) 2.15(54.6)

Valve Spring(Note 1)

Closed at1.88 in. (47.8 mm)

Does Not Apply

110Lbs.(489N)

(Note 1)(Note 2) Pressure

Closed at1.80 in. (45.7 mm)

74-86 Lbs.(329-382 N)

Does Not Apply

Open at 1.34 in. (35.1 mm)

Does Not Apply

316 Lbs.(1406N)

Open at1.40 in. (35.6 mm)

195-215 Lbs.(867-956 N)

Does Not Apply

Installed Height 1.875(47.6) 1.88(47.7)

Damper or DamperShield

Free Length Does Not Apply

1.86(47.2)Shield Approximate Number Of Coils Apply 4

Valve Spring Fit in Damper Shield .42-.094(1.07-2.38)Interference

Does Not Apply

NOTE 1: 454/502/8.2L Models Only-Test spring pressure with inner and outer spring assembled.

NOTE 2: 7.4L Models Only Test spring pressure with damper shield installed.


Engine 7.4L/7.4L Bravo Three454 Magnum/502 Mag-

num/454 Magnum EFI/502Magnum EFI/8.2L

CAMSHAFT AND DRIVE

Lobe Lift ± 002 (0 051)Exhaust .271(6.683) .300(7.62)

Lobe Lift ± .002 (0.051) Intake .282(7.163) .300(7.62)

Duration at .050 In.(1.27mm)Cam Lift

Exhaust 234° 224°Cam Lift Intake 238° 224°


Journal Out Of Round .001(0.025) Max


Timing Chain Deflection[LH (Standard) Rotation Engine Only]

.375(9.5) from taut position [total .75(19)]

FLYWHEEL


CYLINDER HEAD

Gasket Surface Flatness .007(0.178) Overall Maximum.003(0.076)within a 6 in.(152mm) Span


Cylinder Head TorqueSequences

3.0L/3.0LXTo insure gasket sealing, torque head bolts in threesteps, following torque sequence for each step. Startfirst step at, second step at , and finish with a finaltorque of .

1

26

5

3

49

10 7

8

1. 20 lb. ft. (27 N⋅m)

2. 50 lb. ft. (68 N⋅m)

3. 90 lb. ft. (120 N⋅m)

4.3L/4.3LX

72883

a - Front

a

1. 20 lb. ft. (27 N⋅m)

2. 40 lb. ft. (54 N⋅m)

3. 65 lb. ft. (88 N⋅m)

305/5.0L/350/5.7L

72332

1. 20 lb. ft. (27 N⋅m)

2. 40 lb. ft. (54 N⋅m)

3. 65 lb. ft. (88 N⋅m)

7.4L/454/8.2L/502

72944

1. 20 lb. ft. (27 N⋅m)

2. 50 lb. ft. (68 N⋅m)

3. 85 lb. ft. (115 N⋅m)


Intake Manifold TorqueSequence

4.3L/4.3LXTorque bolts to 35 lb. ft. (48 N•m) in sequence asshown.

72878

a - Front

a

350/5.7LTorque bolts to 35 lb. ft. (48 N•m) in sequence asshown.

72327

1

2

35

67

8

9

1011

12

4

454/7.4L/502/8.2LTorque bolts to 35 lb. ft. (48 N•m) in sequence asshown. On 502 Magnum EFI, torque bolts to 25 lb. ft.(34N•m).

1

23

5

10

11

6

7

4

8

13

15

1614

12

972515


Dipstick Specifications4.3L/4.3LX

UNIT OF MEASUREMENT In. (mm)

72887

1/2(13)

25-7/16(646)

3/4(19)

FULL

ADD

41092-1MCM

26-7/8(682)


Dipstick Specifications (Continued)350/5.7L


72341

* Engines with Plastisol Coated Oil Pans

1/2(13)

1/2(13)

1/2(13)

1/2(13)

31 (787) 13-29/32 (353) 32 (814)

33-1/2 (849)

14-25/32 (375)

16-1/4 (413)33-1/4 (845) 15-19/32 (396)

3/4(19)

15/16(24)

3/4(19)

FULL FULL FULL FULL

ADD ADD ADD ADD

23/32(18)

15297MCM

805395MIE

Borg-WarnerIn-Line andHurth 630A

Transmissions*

164825.7L Competition

Ski and 350Magnum

TournamentSki

805394MIE

Borg-WarnerV-Drive

Transmission*


Dipstick Specifications (Continued)454/7.4L/502/8.2L


72341

1/2(13)

1/2(13)

1/2(13)

33-1/2(849)

15-1/8(384)

19-7/64 (485)

35-1/4 (895)

17-13/64 (437)

1/2(13)

19/32 (15)

59/64(23)

FULL FULL FULL

ADD ADD ADD

805567MCM

821503-3MIE

Borg-WarnerIn-Line

Transmissions

821503-4MIE

All TransmissionsExcept

Borg-WarnerIn-Line

16-43/64(423)


Diagrams for Tool UsageIMPORTANT: Check for specific Tool,TorqueSpecification and Measurements under the En-gine Specifications.

Valve Spring Removal With Head On

72306

a - Valve Spring Compressor b - Rocker Arm Nut

b

a

Valve Spring Removal With Head Off

72333

a - Valve Spring Compressor

a

Valve Guide Cleaner

72335

a - Valve Guide Cleaner

a

Checking For Cylinder Head Flatness

72307

a - Straight Edgeb - Feeler Gaugec - Take Measurements Diagonally Across Head

(Both Ways) and Straight Down Center Head

b

a


Rocker Arm Stud Replacement1. Place large sleeve, flat washer and nut over stud,

then turn nut until it bottoms out on studthreads.

72309

a - Large Sleeveb - 3/8-24. Nut - Turn until Nut Bottoms Out on

Stud Threads, Then Remove Nut Using Rocker Arm Stud Remover

ba

2. Remove nut and install small sleeve on stud. Turnnut to remove stud.

00000

72310

a - Nutb - Small Sleevec - Large Sleeve

b

c

a

3. Ream stud hole, whenever installing an oversizestud, using appropriate reaming tool.

4. Install new stud with rocker arm stud installer.

72311

a - Rocker Arm Stud Installer

a


Checking Valve Spring HeightCheck installed height of valve springs. Measure fromspring seat to top of valve spring, as shown. If mea-surement exceeds specified height, install a valvespring shim and recheck. DO NOT shim valve springsto give an installed height less than the minimum spe-cified.

05037

Cutaway Scale

72339

a - Valve Spring Installed Height

a

Checking Valve Spring PressureUsing valve spring tester, as shown, check valvespring tension with dampers removed. Refer to“Specifications.”

IMPORTANT: Springs should be replaced if notwithin 10 Lb.(44 N) of specified tension.

72308

a - Valve Spring Testerb - Torque Wrench

b

a


Checking For Valve Guide WearIf clearance exceeds specifications, it will be neces-sary to ream valve guides for oversized valves, asoutlined under “Valve Guide Bore Repair.”

72336

a - Valve Stemb - Dial Indicatorc - Valve Guide

b

c

a

Valve Guide Bore RepairMeasure valve stem diameter of old valve being re-placed and select proper size valve guide reamer.

Ream valve guide bores, as shown.

72337


Removing The Torsional Damper

72345

a - Torsional Damper Remover

a

Installing torsional damper on crankshaft by turningnut until it bottoms out.

72346

a - Torsional Damper Remover

a

Installing Oil Seal In Cover WithCover Still On Engine

72348

b

a

a - Crankcase Front Cover Seal Installer b - Support (to Prevent Distorting Cover)

Installing New Seal With CoverRemoved

72347

a

a - Crankcase Front Cover Seal Installer


Flywheel Runout - .008 In. (0.203 mm)

72353

a - .008 in. (0.203 mm) Max. Runoutb - Push Flywheel and Crankshaft Forward as Far

as It Will Go when Taking Reading

a

b

Rear Main Seal RemovalIMPORTANT: Remove seal by using a screwdriverto pry it out of retainer as shown.

72355

a - Rear Sealb - Seal Retainerc - Slots (Three)

b

c

a

Using Rear Main Seal Installer.

72356

a - Rear Main Seal Installer (P/N J-26817-A)

a


Checking Clearance On CrankshaftJournalsIMPORTANT: Do not turn crankshaft when gaug-ing crankshaft journals.

Place a piece of gauging plastic the full width of thebearing (parallel to the crankshaft) on the journal asshown.

72357

a - Gauging Plasticb - Journal

b

a

Checking Clearance On Rod JournalsIMPORTANT: Do not turn crankshaft when gaug-ing rod journals.

72361

a - Gauging Plastic

a

Without removing the gauging plastic, measure itscompressed width (at the widest point) with the grad-uations on the gauging plastic envelope.

Measuring Crankshaft End PlayMeasure crankshaft end play by forcing the crank-shaft to the extreme front position. Measure at thefront end of the rear main bearing with a feeler gaugeas shown.

72360

a

a - Force Crankshaft to Extreme Forward Position

Measuring Piston Ring GapMeasure gap between ends of ring with a feelergauge as shown.

72372


Position Of Piston Rings On PistonsIMPORTANT: Be sure ring gaps are properly posi-tioned as shown.

72373

Ring Gap Location

ENGINE LEFT ENGINE RIGHTENGINE FRONT

A - Oil Ring Spacer Gap (Tang in Hole or Slot within Arc)B - Oil Ring Rail GapsC - 2nd Compression Ring GapD - Top Compression Ring Gap

1-3-5-7 Cylinders 2-4-6-8 Cylinders

Piston OrientationNotch on piston must be positioned correctly for en-gine that is being repaired.

72369a - Notch

a

72370a - Notch - Toward Front in MCM and MIE (LH)

Rotation Engines; Toward Rear in MIE (RH)Rotation Engines

a


V-6 and V-8 Piston InstallationIMPORTANT: Be sure to install new pistons in samecylinders for which they were fitted, and used pistonsin same cylinder from which they were removed. Eachconnecting rod and bearing cap should be marked, be-ginning at front of engine (1, 3, 5 and 7 in left bank and2, 4, 6 and 8 in right bank). Numbers on connecting rodand bearing cap must be on same side when installedin cylinder bore. If a connecting rod is ever transposedfrom one block or cylinder to another, new bearingsshould be fitted and connecting rod should be num-bered to correspond with new cylinder number.

72374

a - Piston Ring Compressor

a

Cylinder Wall Inspection AndMeasurementMeasure cylinder walls for taper, out-of-round or ex-cessive ridge at top of ring travel. This should be donewith a dial indicator or inside micrometer. Carefullywork gauge up and down cylinder to determine taperand turn it to different points around cylinder wall todetermine out-of-round condition. If cylinders exceedspecifications, boring and/or honing will be neces-sary.

72385

“A” = At right angle to centerline of engine“B” = Parallel to centerline of engine“Out-of-Round” = Difference between “A” and “B”“Taper” = Difference between measurement “A”

at top of cylinder bore and “A” measurement at bottom of cylinder bore

Cylinder Measurement


72386

Measuring Cylinder Bore

72387

Measuring Cylinder Bore

Checking Deck SurfaceIf surfaces are warped more than .003 in. (0.07 mm)in a 6 in. area or .007 in. (0.2 mm) overall, block mustbe resurfaced

72388

a - Machinist’s Straight-Edgeb - Feeler Gauge

b

a


Camshaft Gear And SprocketInstaller

72377

a - Crankshaft Gear and Sprocket Installer (P/N J-5590)

a

Checking Timing Chain DeflectionThe deflection is the difference between these twomeasurements. If the deflection exceeds 3/4 in. (19mm), timing chain should be replaced.

72376

a - Reference Point

a

Alignment Of Timing MarksNOTE: .Flat lifter timing gear is shown. Roller lifter gearshave similar timing marks.

72376

a - Timing Marks Alignedb - Locating Pin

b

a

Standard (Left Hand) Rotation Shown

Measuring Lobe LiftPosition indicator with ball socket adaptor tool onpush rod. Be sure that push rod is in lifter socket.

72380

a - Ball Socket Adaptor Tool

a

เครื่อง 4.3 l gm

Automotive

4lbravo onebravo two7

test spring pressure

maxseat widthintake 1 32

oil pan screw

remote oil connector

maxtiming chain deflection

maxtaper productionthrust side

valve spring removal