GM Cylinder Head Tightening Specification Clarification - Engine Builder Magazine

GM Cylinder Head Tightening Specification Clarification

Affects:

1993 Cadillac Allante, Sixty Special (FWD)

1993-96 Cadillac Fleetwood

1993-99 Cadillac DeVille, Eldorado, Seville

1994-99 Cadillac Concours

1995-99 Oldsmobile Aurora

with 4.0 L or 4.6 L Engine (VINs C, Y, 9 – RPOs L47, LD8, L37)

Cylinder Head Installation

Torque specification and sequence for the cylinder head bolts (1-10) using a torque angle meter (J 36660-A):

1. First Pass – 30 ft.lbs. (40 N-m)

2. Second Pass – 70 Degrees

3. Third Pass – 60 Degrees

4. Fourth Pass – 60 Degrees (190 Degrees total)

The torque specification for the three front M6 cylinder head bolts is:

106 in.lbs. (12 N-m)

Some or all of this information was provided by the Automotive
Parts Remanufacturers Association (APRA). For more information on
technical bulletins available through APRA call 703-968-2772 or visit www.AutoBulletins.com.

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