The invention discloses a high-stability cooling pump for a motor, and belongs to the technical field of water pumps. A locking sleeve tightly arranged on a water pump shaft in a sleeving mode is additionally arranged on a drainage
impeller, and a plurality of pressing bent pipes distributed with
impeller blades in a staggered mode are annularly distributed on the locking sleeve; the inner end of the pressing bent
pipe is not arranged in a protruding mode, flexible sleeving between the drainage
impeller and the water pump shaft is not affected, when the pump body is in a working state, part of cooling liquid guided into the drainage impeller is guided into a water passing cavity formed in the end of the water pump shaft, and the cooling liquid is guided into the pressing bent
pipe at a high speed through the drainage hole under the action of
centrifugal force; the cooling liquid presses the
piston to move towards the inner side of the pressing bent
pipe, the filler is extruded to one end of the elastic sleeve, the bottom end of the elastic sleeve extrudes towards one side of the pressing cavity along with the filler, and therefore high-stability
insertion connection between the pressing bent pipe and the water pump shaft during centrifugal work is achieved, and it is effectively guaranteed that the drainage impeller is not prone to being disengaged from the water pump shaft under high-speed rotation.