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For 1990-2009 cars only

ACCESSORY DRIVE BELT WEAR DIAGNOSIS PROCEDURE

MODELS AFFECTED: 1988-1989 ALLANTES

Some 1988-1989 Allantes may experience serpentine drive belt wear (i.e., premature belt shredding). On vehicles with this condition the drive belt rides up on the inboard flange of the generator pulley. Prolonged use in this condition will result in belt failure or belt thrown off.

This condition may be caused by mismachining of the generator support bracket to the surface on which the idler pulley is attached. If this surface is not perpendicular to the generator pulley, the resulting angularity will cause the belt to ride up.

Vehicles Involved

- 1988 Allantes in VIN range JU101932 to JU102432 - 1989 Allantes in VIN range KU100001 to KU100635

Repair

Inspect suspect vehicles as follows:

1. Note that over an approximately 90 deg. arc the idler pulley and generator fan blade overlap.

2. Measure the distance between the back flange of the idler pulley and the front face of the generator fan blade.

3. This clearance must be greater than 0.100" and also have a side-to-side difference less than 0.020".

4. If the above dimensions are beyond specifications, generator support must be replaced.

VEHICLE SERIES Operation Operation -------------- Description Number C D E J K V ----------- ------ --------------------- Bracket, Generator Mounting-Replace J4160 .6

Part Group: 2.277 Policy: T

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.