21L/25AX Service Carburettor Body OS22582100 by O.S. Engine  [OS22582100]

Service replacement body for 21L/25AX carburettors

This item, designated OS22582100 from O.S. Engine, acts as the structural housing for compatible carburettors marked 21L or 25AX. It locates and supports throttle and idle components and defines mounting interfaces.

Install the replacement in a tidy workspace and retain small parts in trays. Prior to final assembly, inspect the throttle shaft, gasket faces and mounting bosses for damage or wear that could compromise sealing or throttle behaviour.

The body itself does not alter jetting, but a worn or distorted housing can affect how reliably the carburettor keeps adjustments. Check throttle linkage alignment and any vacuum or synchronization settings as part of the tuning routine, and avoid overtightening fasteners.