PURPOSE: To improve an effect of radiating friction heat by fixing a thermally good conductor member to a part of large deformation degree of an impeller blade in the peripheral surface of an impeller liner, in the case of a pump in which an impeller, having a plurality of flexible blades, is rotatably provided in the impeller liner.

CONSTITUTION: A suction water pump, suited for a seawater pump or the like for cooling inboard/outboard engines, has a suction water port 21 and a delivery port 22, and a synthetic resin-made pump case 24, provided with an impeller liner 23, and an impeller 25, radially provided with impeller blades 251... consisting of a flexible material of rubber or the like, are provided. Here a thermally good conductor member 11 of copper or the like is buried in a part above a cam part 26 of the impeller liner 23. The bottommed cylindrical impeller liner 23, consisting of stainless steel, is press-fixed so as to touch the lower surface of this thermally good conductor member 11. The suction water pump is made capable of being fixed by a bolt to a mounting bracket by forming a screw hole 112 in this thermally good conductor member 11.