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Senaka B

one year ago

Solex Carburettor: Its Types and Working Principle

Solex Carburettor: Its Types and Working Principle




Introduction to Solex Carburettor



Solex is a French manufacturer of carburettors and the powered bicycle VéloSoleX. Solex carburettor is used in may European automobile industries. Such big industries as Rolls-Royce, Volkswagen and Mercedes Benz.



Solex carburettors are invented by Marcel Mennesson and Maurice Goudard founder of Solex company. Solex carburettors widely used by many European makers also used in passenger cars and commercial vehicles.



As we already know the function of carburetor:



  • It combines air and fuel creating a highly combustible mixture,


  • carburettors regulate the ratio of air and fuel, and


  • carburettors control the engine’s speed.


  • Description of Solex Carburetor



    Solex carburettor is a down draught type carburettor. It consists of the devices for starting, idling normal running and acceleration. These are described in brief as follows.



    The figure shows a  starting device for Solex carburettor. It consists of a starter valve in the form of a flat disc having holes of different sizes.



    These holes connect the starter jet and petrol jet sides to the passage which opens into the air horn below the throttle valve. The starter lever is operated by the driver from the dashboard, which adjusts the position of the starter valve so that either bigger or small holes come opposite the passage.



    Working of A Solex Carburettor



    At the time of starting, bigger holes connect the passage so that more fuel may go to the engine.



    The throttle valve is closed, the whole of engine suction is applied to the starting passage 1. The petrol from the float chamber passage through the starter petrol jet and rises into passage 2, it comes out and mixes with the air entering through the air jet. This air-fuel mixture is rich enough for starting for the engine.



    After the engine has started, the starter lever is taken to the 2nd position. So that smaller holes connect the passage reducing the amount of petrol. In this position, the throttle valve is also partly open so that the petrol is also coming from the main jet.



    The reduced mixture supply from the starter system in this situation is however sufficient to keep the engine running. When the engine reaches the normal temperature, the starter is taken to “off” position.



    Classification of Solex Carburettors



  • Solex carburettors are classified by three main categories

  • By it’s the type,


  • the bore of throttle chamber and


  • by its model.


  • Solex carburettors classified according to there direction of flow through the carburettor

  • Updraught Carburetors


  • Horizontal Carburetors


  • Downdraught Carburetors


  • According to the layout of the induction system

  • Simple Carburetor for single induction manifold


  • Dal port Carburetor for two induction manifold


  • Dual port compound Carburetor for single induction manifold