1-15. Gas Producer Fuel Control. The gas producer fuel control has a bypass valve, metering valve,
acceleration bellows, governing and enrichment bellows, manually operated cutoff valve, maximum
pressure relief valve, torque tube seal and lever assembly, and a start derichment valve. The maximum
pressure relief valve protects the system from excessive fuel pressure.
Fuel enters the control from the engine fuel pump and filter assembly and is delivered to the metering
valve. The bypass valve maintains a constant pressure differential across the metering valve. Also, excess
fuel is bypassed to the fuel pump and filter assembly through an external line connecting the pump
bypass inlet to the bypass outlet port of the gas producer fuel control.
The metering valve is operated by lever action through movement of the governor and acceleration
bellows. Metering valve area depends on valve travel. Before light-off and acceleration, the metering
valve is set at a predetermined open position by the acceleration bellows under the influence of ambient
pressure (Pc at zero rpm ).