1989 - 1990 Corvette: Service Bulletin: Convertible: Mounting Bracket Rattle at Rear of Hardtop

Source: Chevrolet Dealer Service Bulletin
Number: 90-203-10
Subject: Mounting Bracket Rattle at Rear of Hardtop
Model Year: 1989-1990 Y Car Convertible

Some 1989 and early 1990 Chevrolet Corvettes (before VIN 106253) equipped with the convertible hardtop option (CC2) may exhibit a rattle at the rear of the hardtop caused by loose hardtop mounting brackets.

Some of these brackets were mounted with rivets which were not long enough to provide enough retention to prevent the rattle.

To correct this condition, the following procedure should be performed.

Procedure:

Remove hardtop assembly as outlined in the Service Manual.
Place the hardtop assembly upside down on a clean protective surface.
Using a 5/16 in. carbide tip drill bit and a DRILL STOP SET AT 1/2 INCH, drill the heads off of the four rivets holding the bracket to the hardtop assembly.

IMPORTANT: The Drill stop is necessary because the interior of the top is constructed of a foam material. The bit, without a drill stop, may go through the foam and through the exterior surface of the top. Also, the carbide tip drill bit is necessary because the rivets are stainless steel.
Using a hammer and a nail or small punch, lightly tap the old rivet bodies into the foam core of the hardtop. The rivets should be driven about 5/8 inch into the foam core.

IMPORTANT: Before securing the bracket to the roof assembly, be sure to position the roof retaining bolt in the bracket.
Install new stainless steel rivets, P/N 10064339 to secure the bracket. Part is currently available from GMSPO.
Repeat steps 3 through 5 for opposite side of the hardtop assembly.
Reinstall roof assembly as outlined in the Service Manual.

Labor Operation Number: T1582

Labor Time: 0.9 Hours

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.