Water jacket spacer production method

A method for producing a water jacket spacer that is disposed in a water jacket provided to a water-cooled internal combustion engine, and controls a flow of a coolant,

• the water jacket spacer comprising a plurality of segmented molded products in which a plurality of arc-shaped circumferential surfaces are linked through a constricted part,
• the method comprising injection-molding a specific resin material using an injection mold in which a resin flow channel is designed so that a plurality of gates are provided along a longitudinal direction at a position that corresponds to an inner circumferential surface of the water jacket spacer, to obtain a molded product,
• wherein, after opening the injection mold, and ejecting the molded product, the molded product is cooled in a state in which a runner that is connected to the gates is allowed to remain, and the runner is cut off thereafter.

A method for producing a water jacket spacer that is disposed in a water jacket provided to a water-cooled internal combustion engine, and controls a flow of a coolant,

• the water jacket spacer having such a shape that a plurality of arc-shaped circumferential surfaces are linked through a constricted part so that the water jacket spacer can be partially inserted into the water jacket,
• the method comprising injection-molding a specific resin material using an injection mold in which a resin flow channel is designed so that a space for molding two water jacket spacers is formed, and a plurality of bridges are provided along a longitudinal direction, the two water jacket spacers having an identical or different shape so that inner circumferential surfaces thereof face each other, the plurality of bridges being provided at a position that corresponds to the inner circumferential surfaces of the two water jacket spacers, to obtain a molded product,
• wherein, after opening the injection mold, and ejecting the molded product, the molded product is cooled in a state in which the plurality of bridges are allowed to remain, and the plurality of bridges are cut off thereafter.