- Drain the coolant from the radiator into a suitable container. Remove the BVSV.
When draining the coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.
- 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.