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