My husband took the hoover apart to fit a new motor and give it s thorough clean.... We appear to have a bit left over! Its a rubber ring that looks like it goes round a pipe. Its says on it B31 this face up and do not remove! Ahem! Your guidance would be much appreciated!

Hi, sounds like its from the pre motor ( washable) filter house. Take the filter out and fit it around the centre shaft with the writing face up,then put the filter back in and this will push the seal back in place. Don't worry ,there will be no lasting damage.