Air Cleaner Cold Weather Modulator
Vacuum of 16 in. Hg applied to vacuum motor side of modulator should hold or leak as follows:
MODULATOR SWITCHING TEMPERATURE
| Valve Color | Holds Vacuum | Leaks Vacuum |
|---|---|---|
| Black | Below 20°F (-7°C) | Above 35°F (2°C) |
| Blue | Below 40°F (4°C) | Above 55°F (13°C) |
| Green | Below 50°F (10°C) | Above 76°F (24°C) |
| Yellow | Above 65°F (18°C) | Below 50°F (10°C) |