- Drain the coolant from the radiator into a suitable container. Remove the BVSV.
- Cool the BVSV to below 95°F (35°C) with cool water. Blow air into a hose that is connected to the BVSV and check that the BVSV is closed.
- Heat the BVSV to above 129°F (54°C) with hot water. Blow air into a hose that is connected to the BVSV and check that the BVSV is open.
- If the BVSV fails the inspection replace it. Apply a liquid sealer to the threads of the BVSV and reinstall it on the engine. Refill the radiator with coolant.
The Canadian models use a jet valve, it can be checked by blowing air into it from each side to see if it is clogged.