how can I fix my wifes leaking hoover commander 6kg top loader. I have the ?

I have the back off without breaking anything - worked out how to get the top loading lid off - can see water on the base etc but not sure how to take things further - i did note that the filter inlet for the cold water (all we ever use) was full of clogging rust/gunk but cant see how that would cause the troiuble. What is the rubber ?breather ?overflow very flexible hollow rubber sock that comes off the bottom of the machine on the left and attached to a white plastic ?overflow lip that screws onto the back metal plate? Hoover commander 6kg top loader maybe 5 years old