Bi-Metallic Vacuum Switching Valve (BVSV)
- Drain coolant. Remove BVSV and immerse threaded portion in cold water below 86°F (30°C). Blow air into either port to verify BVSV is closed.
- Heat water to about 111°F (44°C). Blow air into either port and verify BVSV is open. If BVSV performed as described, it is okay. Apply sealer to threads of BVSV and reinstall. Fill radiator with coolant.