Which devices are used for enriching the air/fuel mixture when starting a cold engine?

The method for enriching the air/fuel mixture when starting a cold engine involves using specific devices that facilitate the transition from cold to warm operation. The primer and choke are specifically designed for this purpose.

The primer is a small bulb or pump that allows the operator to manually inject fuel directly into the carburetor or intake. This ensures there is a sufficient amount of fuel available for starting when the engine is cold and has not yet begun to draw fuel into the system through normal operation.

The choke, on the other hand, restricts the airflow into the engine, temporarily enriching the mixture of fuel and air. When the choke is engaged, it effectively increases the fuel ratio, which is essential for starting a cold engine as it requires a richer mixture to ignite effectively and run smoothly until it warms up.

Together, the primer and choke provide the necessary enrichment of the air/fuel mixture needed for reliable starting in cold conditions.