I have a maytag dishwasher that uses the motor assembly 6-904608 / 99001424. A metal bit got inside the assembly and broke a plastic fin, on what I think is normally labeled part 24.

Now the lower arms run into resistance and get stuck if the upper housing is at all secured. I have to leave the screws loose or else it doesn't work.

One screw guide for the upper housing seems askew a bit, so I suspect repeatedly taking screws in and out messed it up, but I don't know why the top cover (from either the new or old motor) is generating so much trouble.