A padlock includes a lock body, a shackle receivable in first and second shackle openings in the lock body, and a locking mechanism disposed in the lock body. The locking mechanism includes at least one locking member, a key cylinder rotatable between a locked position and an unlocked position, an actuator assembled with the key cylinder for co-rotation therewith, and a torsion spring having a first end engaging the lock body and a second end engaging the actuator to rotationally bias the key cylinder toward the locked position. The actuator includes a projection that engages a portion of the lock body when the key cylinder is in a locked position, and a blocker portion aligned with the at least one locking member to hold the at least one locking member in locking engagement with the shackle when the key cylinder is in the locked position.