On Sedan models, the fuel tank is located in front of the luggage compartment, and on Estate models, it is located under the trunk floor.
Fuel from the fuel tank through the fuel filter and the pipeline is taken by the fuel pump and then under pressure is supplied to the carburetor float chamber. The float and needle valve control the level of fuel in the float chamber. Excess fuel is returned to the fuel tank through the fuel return line.
The air filter mounted on the cylinder head cover or on the carburetor contains a replaceable filter element. A damper thermostat is installed in front of the air filter. The thermostat maintains the temperature of the air entering the engine at an optimal level due to the fact that the damper, controlled by the thermostat, ensures that either cold air enters the engine or air heated by the exhaust manifold.
On vehicles with a STROMBERG CD T175 carburetor, cold start fuel delivery and idle speed are controlled by a delay valve. The valve consists of a bimetallic strip, which is heated by passing an electric current through it and controls the vacuum in the diaphragm housing of the control damper. When starting a cold engine, the delay valve closes the vacuum to the diaphragm and the damper remains closed. In the process of heating the bimetallic plate after starting the engine, the vacuum gradually increases, and the damper, opening, regulates the idle speed. There is also a solenoid valve that shuts off the fuel supply. This valve prevents the engine from running after the ignition is turned off, and also limits the maximum engine speed by shutting off the fuel supply if the engine speed exceeds the maximum allowable.
The idle speed and the air-fuel mixture on vehicles with a PIERBURG carburetor are controlled by the throttle and choke actuators. The operating parameters of the engines are monitored by sensors mounted on the engine and connected to an electronic control device (ECU). At engine speeds above idle, the choke actuator changes the position of the choke and therefore the amount of air entering the engine. When the engine is idling, the throttle actuator controls the fuel supply by changing the position of the needle in the air jet. The ECU, by comparing the engine idle speed with a set value, maintains the optimum idle speed for all engine operating conditions. The throttle position potentiometer is used as feedback in the control system.
Warning! Gasoline is extremely flammable and explosive, so care must be taken when working on any part of the fuel system.
Attention! Work on the fuel system must be carried out in a well-ventilated area, for which all windows and doors can be opened to create a draft.
Attention! When working on the fuel system, do not use open flames, electric welding, or tools that may generate sparks. Make sure there is a charged fire extinguisher in the immediate vicinity of the workplace.
Attention! Use goggles to protect your eyes from getting fuel in them. If fuel comes into contact with skin, wash the area with plenty of water.
Warning! The container in which the fuel was located contains fuel vapors and is potentially explosive.
Attention! Keep the fuel system clean as dirt entering the fuel system passages can block them and prevent the engine from running properly.