Impeller of motorboat

A motorboat impeller and element for mounting and dismounting said impeller,

• wherein said motorboat impeller comprises:
• an axial portion of a conical construction having a front end with an outer diameter smaller than an outer diameter of a rear end thereof, said axial portion further provided with a first axial hole extending through said front end and said rear end of said axial portion, said axial hole having in a rear end thereof an inner threaded portion;
• and
• a plurality of blades attached to the periphery of said axial portion;
• wherein said first axial hole is provided at the front end thereof with a first shoulder extending outward from an axis of said axial portion, and a plurality of retaining slots on an inner wall of said first axial hole which are spaced equidistantly and have a predetermined length extending rearward from said first shoulder in the direction of the axis of said axial portion,
• wherein said element for mounting and dismounting said impeller comprises;
• a body portion having a polygonal cross section;
• an axial hole extending through a front end and a rear end of said element;
• a plurality of retaining blocks having a predetermined length and extending rearward from said rear end along the direction of an axis of said element, said retaining blocks corresponding in location to said retaining slots.