Created animation not working on model

I downloaded a model from Mixamo, along with its animation and all is working. I just wanted to create an animation in unity (Create->Animation) which simply moves the z-axis. I used key-frames to do it, very simple. Except when I put it in the animator it doesn't work. If i would for example use it on a 3D cube, it would work, but not on the model, nothing moves when the animation plays in the animation controller. Any suggestions?