Thermal Vacuum Switching Valve

Fig.76 - Testing Thermal Vacuum Switching Valve:

1981-82 3A-C Engine
1. Drain coolant and remove valve.
2. Check that air flows from pipe "J" to pipes "M" and "L", and from pipe "K" to pipe "N" with coolant temperature below 45° F, Fig. 76.
3. Check that air flows from "K" to "N" and "L", and from J" to "M" with coolant temperature between 63° and 122° F.
4. Check that air flows from "K" to "M" and "L", but does not flow from "J" to other pipes with coolant temperature above 154° F.
5. If test results are not as described, replace valve.
6. Apply liquid sealer to valve threads and install valve, then refill coolant.