ENGINE BUZZ OR WHINE LOOSE ENGINE MOUNTING BOLT

ENGINE BUZZ OR WHINE DUE TO LOOSE ENGINE MOUNTING BOLT (Illustration has been revised and Service Note added.)

VEHICLES AFFECTED: 1987 N CAR WITH 3.0L (VIN CODE L) ------------------

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

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

Step 1. If bolt is missing, replace it with part number 11509793 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.).

The new bolt (Part No. #11509793) was in production 4-13-87, breakpoints:

Oldsmobile HM278190 Buick HM065673 Pontiac HC870266

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.