1988 - 1989 Corvette: Service Bulletin: Yellowing Paint on or Around Headlamp Doors (White Only)

Subject: Yellowing Paint on or Around Headlamp Doors (White Only) 
Model and Year: 1988 - 1989 "Y" CAR (CORVETTE)
Source: Chevrolet Service Bulletin
Bulletin Number: 89-136-10
Date: 06-apr-1989

TO: ALL CHEVROLET DEALERS

Some customers may comment regarding the yellowing of paint on or around the headlamp doors on 1988 - 1989 Corvettes (WHITE PAINT ONLY).  This condition is due to a reaction of the clear coat to some rubber components in the engine compartment.

IMPORTANT:

1. Vehicles with VINs after K5113927 are not affected with this condition.
2. Previously repaired vehicles can be identified by inspecting the underside of the inlet radiator hose for new part #10135650 molded into the hose, or a green band on the drive belt, new part #10105314.

To correct this condition, a new service kit, P/N 10105330, is available from GMSPO and contains the following parts:

REPAIR PROCEDURE:  (Use on vehicles with VINs prior to J5120731.)

1. Drain the cooling system and replace the radiator hoses, throttle body coolant hose, heater inlet hose and the heater outlet hose
   
   IMPORTANT:  Both KC4 option  (Engine Oil Cooling System) and standard heater outlet hoses are included in this kit.  The correct hose usage will depend on the vehicle option content. 
   
   
2. Replace all A.I.R. hoses included in the kit.
3. Replace the accessory drive belt and insure proper routing
4. Remove and discard the hood support (gas tube).
5. Make sure that when refilling the cooling system, the proper coolant refill procedure is used.  Refer to Service Manual Section 6B.
6. Wash the engine compartment and underside of the hood to remove any drive belt dust or rubber residues.

In addition to the installation of the kit, both headlamp doors should be replaced.  New headlamp door, P/N 10137733 (left) and 10137734 (right) are available from GMSPO.

It may also be necessary to repaint the right side headlamp bezel only, if heavier yellowing conditions are present.  See the PAINTING section later described in this bulletin.

REPAIR PROCEDURE:  (Use on vehicles with VINs after J5120731 but prior to K5113927.)

1. Install kit as previously described above in Steps 1 through 6.
2. Refer to the PAINTING section for determining the repairs for "FAINT" or "HEAVIER" yellowing.

PAINTING

Depending on the amount of yellowing condition, a number of repairs are possible.

PAINT YELLOWING

1. Use wax and grease remove to remove dirt and grime from the yellowed area on the headlamp door or surrounding hood.
2. Polish the yellowed areas with 3M (R) Finesse-it, #05928, or equivalent to remove swirl marks.

HEAVIER YELLOWING

More severe yellowing may require either "spot/partial panel repair" procedures.  Please refer to past "PRO TECH" publication, PROGRAM CV9-1-(88-8), CORVETTE REFINISHING TECHNIQUES.

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.

© Copyright General Motors Corporation. All Rights Reserve

Article ID: 164
Created: July 13, 2014
Last Updated: July 13, 2014

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