Whirpool won't drain

:confused: although it’s over 10 yr old, not often used, however it does not drain. Have removes blades and drain filter, cleaned for clogs and checked hoses. Still does not drain, also asking if there is supposed to be a small ball or marbel in the drain hose.
Please help,
Thank you, Mark

remove bottom kick plate cover, remove drain check valve .it is attached to motor on right side, white plastic tube 3 inches long.drain hose attached to it, un threads counter clockwise, crap collects there, reataches at anglefacing downward into motor