The diaphragms play an essential role in the proper functioning of the carburetor, as each brand has its own specific diaphragms, as Zenith carburetors, Solex carburetors and Pierburg carburetors come in various models.

The diaphragm is the one that is most often changed part, if its rubber part is pierced it no longer ensures watertightness.

The enrichment diaphragm and the starter opening assistance diaphragm when present on the carburettor also need to be changed when the carburettor taken appart and cleaned.