Thermal Vacuum Valve

Fig. 78 Thermal vacuum valve operating specifications.:

1. Drain cooling system.
2. Remove thermal vacuum valve.
3. Place thermal vacuum valve in a container of water with a thermometer.

CAUTION: Do not allow any water to get inside the thermal vacuum valve.

4. Plug the bottom port on 1983 Pickup with gas engine, on center port on all other models.
5. Apply vacuum to center port on 1983 Pickup with gas engine, or top port on all other models.
6. Slowly heat water and check that thermal vacuum valve operates within specifications, Fig. 78.