ENGINE BUZZ OR WHINE LOOSE ENGINE MOUNTING BOLT

1987 CALAIS WITH 3.0L (VIN CODE L) ENGINE

This bulletin supersedes Dealer Technical Builetin 87-T-49. The illustration has been revised to indicate the removal of the locating bolt after all engine mounts are secured. Dealer Technical Bulletin 87-T-49 may be discarded. Also, a Service Note has been added.

A whine, buzz or missing bolt on a 1987 Calais with a 3.0L VIN Code L engine with A/C may be caused by an engine mounting bracket bolt losing torque.

Inspect the right front engine mounting bracket for a loose or mining bolt, see Figure 1. Follow the steps outlined below:

Step 1. If bolt is missing, replace it with part number 11509793 or equivalent and torque to 60-80 N-m (44-60 lbs. ft.).

Step 2. If bolt is loose, remove the bolt, clean the threads and apply Loctite 242 or equivalent to the bolt threads. Torque bolt to 40-60 N-m (30-44 lbs. ft.).

Calais models produced April 13, 1987, (VIN HM278190), and later, have the new bolt 11509793 already installed.

SERVICE NOTE:

Locating bolt shown in Figure 1 must be removed after all engine mounts are secured or engine vibration and noise will be transmitted into car body.

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.