TORQUE TO YIELD HEAD BOLT NEW DESIGN

ALL 1986 3.0L V-6 ENGINES (VIN CODE L) AND 3.8L V-6 ENGINES (VIN CODE A)

A revised "torque to yield" head bolt is now being used on the above engines for 1986. The new bolt looks very much like a "regular" past model head bolt because it does not have a cut down neck. See illustrations. Torque specification for this new "torque to yield bolt" is as follows.

Step

1. Torque cylinder head bolts to 34 N.m (25 ft. lbs.) per sequence shown in illustration.

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

3. Repeat step 2, tightening each bolt an additional 1/4 turn (90 degrees).

NOTE: Unlike those used for 1985, the 1986 bolts may be reused.

Care should be taken when handling the new composition gasket used in conjunction with these bolts to prevent surface or edge damage prior to installation. Also, the gasket should be installed without the use of sealers of any kind.

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.