262 cid / 4.3L Gen + Marine Engine Specifications

Unit of Measurement

 In. (mm) 

Displacement

262 CID (4.3 Liter) 

Bore 

4.00 (101.6) 

Stroke

3.48 (88.39)

 Compression Ratio 

9.3:1 

Heads 

Cast Iron

Intake Manifold

Cast Iron

Block

Cast Iron (2 Bolt Main Bearing Caps)

Rods

Forges Steel 

Pistons

Cast Aluminum 

Crankshaft 

Cast Iron

Camshaft 

Steel

Diameter

4.0007-4.0017(101.618-101.643) 

Out of Round

Production 

.001 (0.025) Maximum

Service

.002 (0.051) Maximum 

Taper

Production

Thrust Side

.0005 (0.012) Maximum 

Relief Side 

.001 (0.025) Maximum 

Service

.001 (0.025) Maximum 

Production

.0007-.002 (0.017-0.05)

Service

.0024 (.001)

Groove Clearance

Production

Top

.02-.06 (0.51-1.52)

2^nd

.04-.08 (1.02-2.03)

Service

.0042 (0.107) Maximum

Gap

Top

.010-.016 (0.25-0.40)

2^nd

.018-.026 (.046-.066) Maximum

Service

.06-.035 (1.524-0.88) Maximum

Groove Clearance

Production

.002-.007 (0.51-0.20)

Service

.02-.08 (0.51-2.032)

Gap

Production

.015-.050 (0.38-1.27)

Service Limit

.009-.065 (0.23-1.65)

Diameter

.9267-.9271 (23.545-23.548)

Clearance

Production

.0002-.0007 (0.005-0.0178)

Service Limit

.001 (0.025) Maximum

Fit in Rod

.0008-.0016 (0.021-0.040) Interference

Main

Journal

Diameter

No. 1

2.4488-2.4495 (62.199-62.217)

No. 2, 3

2.4485-2.4494 (62.191-62.215)

No. 4

2.4479-2.4489 (62.179-62.203)

Taper

Production

.0003 (0.007) Maximum

Service

.001 (0.025) Maximum

Out of Round

Production

.0002 (0.005) Maximum

Service

.001 (0.025) Maximum

Main Bearing

Clearance

Production

No. 1

.0008-.0020 (0.020-0.051)

No. 2, 3, 4

.001-.025 (0.025-0.635)

Service

No. 1, 2, 3, 4

.001-.002 (0.030-0.051)

Crankshaft End Play

.002-.008 (0.05-0.20)

Connecting Rod

Journal

Diameter

2.2487-2.2497 (57.117-57.142)

Taper

Production

.0003 (0.007) Maximum

Service

.001 (0.025) Maximum

Out of Round

Production

.0002 (0.0051) Maximum

Service

.001 (0.025) Maximum

Rod Bearing Clearance

Production

.0013-.0035 (0.033-0.088)

Service

.001-.003 (0.025-0.076)

Rod Side Clearance

.006-.017 (0.15-0.43)

Crankshaft Runout

.001 (0.025) Maximum

Lifter

Hydraulic Roller

Rocker Arm Ratio

1.50 to 1

Valve Lift

Intake

.414 (10.52)

Exhaust

.428 (10.87)

Valve Lash (Intake & Exhaust)

Net Lash No Adjustment

Face Angle (Intake & Exhaust)

45°

Seat Angle (Intake & Exhaust)

46°

Seat Runout (Intake & Exhaust)

.002 (0.05) Maximum

Seat Width

Intake

.035-.060 (0.89-1.52)

Exhaust

.062-.093 (1.58-2.38)

Stem

Clearance

Production

Intake

.0010-.0027 (0.025-0.069)

Exhaust

Service

Intake

.001 (0.025) Maximum

Exhaust

.002 (0.51) Maximum

Stem Diameter

Intake

.34-.3407 (8.636-8.653)

Exhaust

Valve Margin (Intake & Exhaust)

.031 (0.79)

Valve

Spring

Free Length

2.03 (51.6)

Pressure

Valve Closed

76-84 Lb. (338-374 N) at 1.7 in (43.16 mm)

Valve Open

187-203 Lb. (832-903 N) at 1.27 in (32.25 mm)

Installed Height

1.690-1.710 in (42.93-43.43 mm)

Lobe Lift +

.002(0.051) 

Intake

.286-.290 (7.26-7.36)

Exhaust

.292-.296 (7.42-7.52)

Journal Diameter

1.8682-1.8692 (47.452-47.478)

Journal Out of Round

.001 (0.025) Maximum

Camshaft Runout

.002 (0.051) Maximum

Camshaft End Play

.001-.009 (0.0254-0.2286)

Timing Chain Deflection

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

Runout

.008 (0.203) Maximum

Gasket Surface Flatness 

.010 (0.254) Overall Maximum 

Front Bearing Journal

2.1648-2.1654 (54.985-55.001)

Rear Bearing Journal 

1.4994-1.500 (38.084-38.100) 

Rear Bearing Journal Clearance

.001-.0036 (.025-.091)