1976 - 1978 Corvette: Service Bulletin: Cast Aluminum Wheel Porosity Repair

Source: Chevrolet Dealer Service Technical Bulletin
Subject: Cast Aluminum Wheel Porosity Repair
Model and Year: 1976-1978 Corvette
Bulletin Number: 78-T-6
Section: X
Date: Feb., 1978

TO: ALL CHEVROLET DEALERS

Some 1976-1978 Corvettes equipped with YJ8, cast aluminum wheels may exhibit a slow air leak due to a porous condition existing in the wheel. To correct this condition use Dow Corning Silastic 732 RTV, P/N 1051435 or equivalent as described in the following procedure:

1. Remove wheel and tire assembly from car.
   
   
2. Locate leaking areas by inflating tire to 50 PSI and dipping wheel-tire assembly in to water bath.
   
   
3. Mark leak areas and remove tire from wheel.
   
   
4. Scuff inside rim surface at leak area with #80 grit paper and clean area with general purpose cleaner such as 3M #08984.
   
   
5. Apply 1/8" thick layer of adhesive/sealant to leak area and allow twelve hours of drying time.
   
   
6. Mount tire on wheel, pressurize to 50 PSI and check for leaks.
   
   
7. Adjust tire pressure to meet specifications.
   
   
8. Balance wheel and tire assembly.
   
   
9. Reinstall wheel-tire assembly on car.