Valve stem sealing unit for heat engine of e.g. lawn mower, has valve seal interposed between valve guide and valve stem, and spring maintained in place on stem by retainer to ensure return of tulip on base

摘要

The unit has a valve seal (4) interposed between a valve guide (7) and a valve stem (3). The valve seal rests in a counterbore (9) disposed inside a cylinder head (5) and is attached to the valve stem through a circular flange projecting at an upper part (12). A spring (2) maintained on the stem of a valve (11) by a retainer (1) ensures return of a tulip (10) on a base (6). An independent claim is also included for a low power heat engine particularly an IP 60F and IP 70F type engine of a lawn mower equipped with a valve stem sealing unit.