ENGINES WITH A/C OVERHEAT INSTALL FAN MODULE KIT

VEHICLES AFFECTED: 1985-86 'F' WITH A/C AND 5.0L V-8 (VIN CODES 'F', 'G', AND 'H')

Some owners of 1985-86 Chevrolet and Pontiac 'F' cars equipped with an air conditioner and a 5.OL V-8 (LB9, L69, or LG4) engine, are returning to Dealers because of an engine overheating condition.

This condition may be caused by a loss of engine coolant and/or owner aggressive driving habits and occurs more frequently in situations where the terrain is hilly and ambient temperatures reach approximately 380C (1000F).

To increase air flow and provide additional engine cooling, a fan module kit and brace rods are available from GM Parts for Chevrolet and Pontiac. Also required, but ordered separately, is al2O amp generator.

The following procedure is recommended when repairing related engine overheating problems.

PROCEDURE

1. Determine if engine has blown head gaskets due to severe overheat or boil over. Replace gaskets as required.

2. Check for the presence of any possible damage to the radiator air deflector extension and RT. and LT. radiator air side baffles.

3. Check for proper electric cooling fan direction of rotation and correct temperature gauge/sensor operation.

4. Check engine coolant. Add as necessary. Replacement coolant must be a 50/50 mix concentrate of good quality glycol and water to achieve the design intent coolant boil temperature.

5. Thermal Cycle

A. Drive vehicle for at least 15 kilometers without boil over.

B. Allow vehicle to cool down overnight.

C. Check coolant at recovery bottle and at radiator filler neck. Add coolant in both places as necessary.

6. Repeat cycle until no additional coolant is required.

7. If engine overheating still exists, install the parts listed below following instructions included in the fan module kit.

Part Name Chevrolet P/N Pontiac P/N

Fan Module Kit 14101637 14101636

Brace Rod 14044877 (1 Required) 14044877 (2 Required)

Generator 1101258 1101258

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.