Description & Operation
The primary main and slow air jet control system is used on Federal 1500 HF models only. This system is designed to control airflow into carburetor main and slow air jets according to driving conditions. It is also designed to maintain optimum air/fuel ratio.
When solenoid valves are activated by control unit, primary main and slow air jet cut-off solenoid valves supply additional air to each air passage of carburetor, leaning the air/fuel mixture.