Abstract: Machine for the automated fitting of insulative foam inserts into the cores of masonry building blocks includes a frame for straddling, in superposed relation, a masonry block conveyor. The machine has a magazine section for sequentially feeding pairs of laterally compressible inserts linked together in juxtaposed relation by a frangible web of the foam material. The machine includes a vertically reciprocal tamping mechanism for moving each of the linked-pairs of inserts sequentially from the magazine section into the cavities of building blocks being carried on the block conveyor disposed below the machine. The machine further includes adjacent throat channels vertically aligned with the tamping mechanism and with the cores of each building block positioned to receive the inserts therein. The channels are each defined, in part, by a central wedge having its apex disposed upwardly to sever the web and separate the linked-pair of inserts as each is moved through the channels past the wedge.