4.1 ENGINES HEAD BOLT TIGHTENING SEQUENCE

SUBJECT: CYLINDER HEAD BOLT TORQUING INSTRUCTIONS (NOTE: THIS BULLETIN IS A SUPPLEMENT TO BULLETIN 85-6-120)

VEHICLES AFFECTED: 1985 VEHICLES EQUIPPED WITH 3.OL, 3.8L, OR 4.lL ENGINES

The following cylinder head bolt torquing instructions should be used whenever it is necessary to replace cylinder heads or cylinder head gaskets on the above engine.

CYLINDER HEAD BOLT TORQUING INSTRUCTIONS STEP

1. Install new Cylinder Head Bolts each time cylinder head is removed.

2. Torque Cylinder Head Bolts to 34 N.m. (25 ft. lbs.) per sequence shown in Illustration.

3. After completing Step 2, tighten each bolt 1/4 turn (90 degrees) in same sequence.

4. Repeat Step 3, tightening each bolt an additional 1/4 turn (90 degrees).

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.