Thermal Vacuum Valve: Testing and Inspection

Fig. 12 Testing EGR BVSV Closed Position:

Fig. 13 Testing EGR BVSV Open Position:

1. Drain the coolant from the radiator into a suitable container.
2. Unscrew and remove the BVSV.
3. Cool the BVSV to below 35°C (95°F) with cold water.
4. Blow air into inlet pipe J and check that air does NOT pass through valve pipe K. Fig. 12
5. Heat the BVSV to above 54°C (129°F) with hot water.
6. Blow air into inlet pipe J and check that air passes through valve pipe K, (valve open). Fig. 13
7. If a problem is found, replace BVSV.
8. Apply a suitable sealing compound to the BVSV threads and reinstall.
9. Refill the radiator with coolant.