Mixture Heating System: Operation
Mixture heater uses a honeycomb heater design and is situated in the primary side of the carburetor insulator. Resistance to current flow increases as temperature increases, so current is maintained constant. On California models, mixture heating system is activated at temperatures below and deactivated at temperatures above 99°F (37°C). On all other models, system is activated at temperatures below 122°F (50°C) and engine speed above 400 RPM. System is deactivated at temperatures above 122°F (50°C).