A powered dispensing tool includes a housing, a motor positioned within the housing, a rack coupled to the motor for powered translation in at least one of a forward direction and a reverse direction, and a transmission selectively coupling the motor and the rack. The transmission includes an input ring rotatable in response to rotation of the motor in a first direction corresponding with powered translation of the rack in the forward direction, a first clutch member engaged with the rack through an intermediate gear, and a second clutch member that receives torque from the input ring and that is movable in response to rotation of the motor in the first direction toward a first position engaging the first clutch member. The second clutch member is also movable in response to rotation of the motor in an opposite, second direction toward a second position disengaged from the first clutch member.