Solex Carburetor: iFunctionality, Construction, and Benefits

Solex is the brand name that is owned by a subsidiary Italian automotive manufacturer. The original Solex company was French-owned and made carburetors and gasoline-operated bicycles. Solex carburetors were part of different European automobile companies, such as Rolls-Royce Motors, Land Rover, and Volkswagen. But now they are not made by any manufacturers based on French. In this post, we will cover detailed features and related factors for the Solex carburetor. So let’s get started with an introduction to the Solex carburetor.

What is a Solex carburetor?

• The Solex carburetor is made by Marcel Mennesson and Maurice Goddard, who were the founders of the Solex company. Solex carburetors are used in different European vehicles, including commercial vehicles and passenger cars.
• The Solex carburetor is a modification of a normal carburetor.
• The ordinary carburetor operated well for normal working conditions but did not work properly in winter and summer.
• For high acceleration and idle conditions, it works well. The basic work of a carburetor is to provide an air-fuel mixture in an accurate part. The Solex carburetor engine is used for easy starting, and the engine has good working features.

• •The Solex carburetor is a downdraft carburetor. In this carburetor, air enters from the top and releases to the lower side.
• The main disadvantage of this carburetor is that it does not have features to maintain an air-fuel mixture for different driving conditions and also provides different mixtures based on driving conditions.
• The changes in air-fuel mixture for different conditions we can get through the Solex carburetor. The Solex carburetor provides high-mixing engine start and lean mixture for driving at low speed with vehicles.

Structure of Solex Carburetor

• The Solex carburetor comes with a fuel chamber, which is a component that gets fuel from the fuel tank and stores it in the carburetor for making the air-fuel mixture. The fuel chamber comes with a float that maintains the fuel level of the fuel chamber.
• It comes with a main line where the fuel venturi moves to the throat tube. Fuel goes in the venturi throat duct from the main jet that is connected at the end of the main line. The fuel from the main jet evaporates when the choke is opened.
• Fuel from the main jet mixes with air that comes when the choke is opened to make an air-fuel mixture, and that mixture moves to the engine cylinder when the throttle valve is opened.
• The carburetor also comes with 3 pipelines where the engine cylinder gets filled, and they are called pilot jets, pump jets, and starting routes.
• The pump gets fuel from the acceleration pump, and the pilot jet gets fuel from the main jet. There is a partition for the pilot jet pipeline from the mainline.
• The acceleration pump works with the use of an acceleration pedal.
• These acceleration pumps are used at the time of acceleration.
• Pilot jet used at time of no-load conditions. It comes with a pilot bleed orifice that helps the pilot jet to air to make an air-fuel mixture.
• Close to the end of the idle position pipeline, there is an idle screw used for controlling the air-fuel mixture for moving into the engine cylinder.

• The starting path gets fuel from the starting circuit. These starting circuits are used to supply an air-fuel mixture at the time of starting. The starting circuit has a flat disc with holes of different radii for controlling the fuel supply at the time of starting.
• • The starting circuit also comes with an air venturi that provides air to the starting circuit for making an air-fuel mixture. The air-fuel mixture of the starting circuit is given to the engine cylinder from the starting path that exits below the throttle valve.

How does the Solex carburetor work?

There are different modes of operation of the Solex carburetor that are explained here.

Start time working

• At the time of starting, there is a need for a high mixture for the engine. The Solex carburetor is a starting circuit, or bi-starter, for providing a high mixture at the starting time.
• The main work of the starter is to handle issues at the time of engine starting, mostly in cold conditions. It provides a high engine mixture at starting time. The ratio mixture of air and fuel is 11/1; air is 11 parts, and 1 is fuel.
• Normally, the fuel ratio for the engine is 15/1, but for starting that, the ratio is 11/1. The bit starter comes with a flat disc and holes with different diameters.
• The starter petrol jet and starter air jet are configured with holes in the disc, and the air-fuel mixture moves to the engine in a suction stroke from different holes of the starter disc.
• Through these holes, fuel and air move from the bi-starter to the engine. That disc can manually move with the use of a starter level so it can set according to fuel and air demands.
• Larger holes in the disc are used in winter conditions since more fuel is required for starting in low temperatures.

Working During Idling the Engine

• In idling conditions, the vehicle engine is operating but not for vehicle speed. That condition usually exists when the red light of the vehicle goes off, and as a result, the engine is on.
• For idle conditions, there is no load for the engine, but all engine friction is required to keep the engine running. At idle position or slow-running conditions, the throttle valve is completely closed.
• As the throttle valve closed, suction was made with a suction stroke directly operated on the pilot jet.
• The pilot jet is getting fuel from the main line. The pilot jet pipes are configured with the mainline and give fuel to it.
• • The throttle valve closes for idle conditions, and accurate pressure is not produced to suck fuel from the main jet. The suction stroke of the engine directly gets the air-fuel mixture from the pilot jet.
• The fuel from the pilot jet is incorporated and mixed with air sucked from the pilot air bleed orifice from external conditions. The high mixture from the pilot jet was sent to the engine through a tube connected below the throttle valve.
• There is no use for the screw that exists close to the opening of the pilot jet for controlling engine speed by controlling air fuel for the engine.
• There is a bypass configuration that exists over the throttle valve, so if pressure is close to the throttle valve, it can get air fuel from the pass-through design. The throttle valve opens when this close configuration is used.