Strange notches in washing machine motor

[WizardsNipple]

Hi folks I have a hoover washing machine which recently stopped spinning. I took the motor out and found the brushes were worn down so I've ordered a new pair. However on closer inspection I've noticed some notches in the center part of the motor and I'm no expert but it doesn't look right to me. Will I need a new motor or shall I just whack the new brushes in and hope for the best? Please take a look, thanks. 

[Whitegoodshelp]

The holes are just to balance the armature. Here are two articles about diagnosing why a washing machine isn't spinning -

Washing machine not spinning | Carbon brushes diagnostics