The electric motor blows the fuse

[Almendros]

Hi, My Vacuum cleaner blows the fuse. I took the motor out of it and found with a battery test lead that the + and -
points are connected together WHEN switched on,so short circuit, but where ? Carbon brushes are still there and both windings look in good nick and not burnt. Switch and plug are fine. Mystery to me ..Thanks for any ideas

[compostheap]

Try testing both +ve and -ve to earth. If either of them go to earth your motor has burnt out and you need a new vac !
If this is OK. Try checking inside the plug .