the vacuum has 2 carbon brushes/bushes in it... You will find that one of them has warn out.. You will need to remove the pump and disassemble the housing to expose the sealed units. The brushes are actually a sealed unit so you will need to cut the back out of the sealed unit exposing the carbon and the wires. Remove the old carbon and replace with a new carbon and solder the wire back in place. Seal the back with the old piece of sealed unit using electrical tape or heat weld back in place. The carbons will only cost a few dollars and a bit of time and patience compared to the cost of replacing the vacuum unit..
