Single-Function for Standard Cooling

When coolant temperature is below 149°F (65°C) on 6-cylinder and V8 engines, or 120°F (49°C) on 4-cylinder engines, check ball is held against inner seat by spring tension. Manifold vacuum enters through port "1" and is applied through port "D". See Figure.

When temperature goes above specified limits, check ball is moved up in valve and manifold vacuum is applied from port "2" to port "D" on 4-cylinder engines, or carburetor ported vacuum is applied from port "2" to port "D" on 6-cylinder and V8 engines.