A blade housing assembly for a power operated rotary knife including a split blade housing and an expansion sleeve assembly. The split blade housing including an annular blade support section and a mounting section extending from the blade support section. The mounting section includes a split extending through the mounting section and includes a first body portion and a second body portion on opposite sides of the split, the first body portion including a slot extending axially through the first body portion and movable between blade supporting and blade changing positions. The expansion sleeve assembly extends through the slot and includes a split sleeve changeable between first and second circumferences. The expansion sleeve assembly further including a fastener extends through the split sleeve and, when engaged with the split sleeve, maintains the split sleeve in the first circumference and secures the first body portion in the blade supporting position.