Chrysler Air Raid Siren Maintenance Manual

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The Fuel system includes the Fuel Tank, Fuel lines, Fuel Pump and Filter, Carburetor, Intake Manifold and Throttle control. Fuel from the tank passes through the Filter into the Fuel Pump, which is driven by an eccentric on the front end of the Cam Shaft. The Fuel Pump forces fuel into the Carburetor where it is atomized and mixed with air and drawn through the Intake Manifold and Valves into the Combustion Chamber.

The Engine of the Chrysler Air-Raid Siren is designed to give highly efficient performance with the use of either Regular or Premium Fuels available throughout the country. It is recommended that only high quality Fuel be used, the reputation of the Manufacturer being your best guarantee of their product.

The Gasoline Tank should be kept full at all times, this minimizes the amount of air above the Gasoline in the Tank, thereby reducing evaporation of the Gasoline, which increases Gum content in the Gasoline, also reduces "Breathing", the cause of Condensation and the formation of Water in the Gasoline Tank. The capacity of the Gasoline Tank is twenty-five (25) Gallons.


The Carburetor for the Siren Engine is a double barrel down draft unit. The Climatic Control provides efficient operation under all conditions of Starting and Warm-up. Overchoking of a warm Engine is prevented by means of a heat retainer plate located next to the Choke Coil. This plate retards the cooling off of the thermostatic coil, thereby preventing it from closing the Choke while the Engine is still hot. A vacuum controlled Throttle opener, (Figure 4) opens the Throttle about twenty-five (25) percent when the Engine is shut down, as soon as the Engine starts up, this Throttle opener loses control and the function is taken over by the fast Idle cam. The Throttle Solenoid opens the Throttle to wide open position to give the "Warning" and "All Clear" Signal.

The Dual throat Carburetor is mounted on the Intake Manifold so that the two Carburetor throats (Venturi) may be called "Right" and "Left" throats. The Right throat feeds fuelair mixture to number 2 and 8 cylinders in the Right bank, and number 3 and 5 cylinders in the Left bank. The Left throat feeds number 4 and 6 cylinders on the Right bank and number 1 and 7 cylinders on the Left. That does two things: First, it makes all of the fuel passages about the same length. Second, it gives each passage the same load. As a result, the fuel is distributed evenly among all the cylinders and the Engine runs that much more smoothly at all speeds.

The Carburetor has a water-jacketed Throttle body. The purpose of circulating the cooling system water through passages in the throttle body is to prevent stalling which sometimes occurs due to formation of frost or ice on the Throttle valves, caused by extreme humidity between freezing and fifty-five degrees F. In addition it allows for a final positive control of the fuel vaporization at all speeds and loads.

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