Cylinder Head Bolt Torque and Sequence

NOTICE: The torque specifications in this article have been updated from the GM service information website.

CYLINDER HEAD TORQUE PROCEDURE

NOTICE: Whenever a cylinder block or the head bolts are replaced, install the cylinder head and torque the bolts to 65 Nm (48 ft. lbs.). Next, remove the bolts, coat the threads with engine oil and follow the torque angle procedure steps. Torquing the bolts one time prior to following the torque angle steps will make sure proper clamp load is achieved.

NOTICE: The following steps must be completed in sequence. This will make sure of uniform bolt tension.

Fig. 13 Cylinder Head Bolt Tightening Sequence:

1. In sequence, torque the cylinder head bolts to 30 Nm (22 ft. lbs.).

2. In sequence, torque all bolts to 50 Nm (37 ft. lbs.)

3. Install torque angle gage SA9140E (Snap-on Tool 360 or equivalent.)
4. Calibrate gage to zero.
5. In sequence, turn each bolt an additional 90 degrees.