You cannot buy just the motor you have to buy the whole base unit plastic housing fan and lampholders.The noise could be caused by a number of things
1:there could be a piece of coal stuck in the fan impeller
2:check the impeller is central in the housing if not use a small screwdriver and lever it across on the shaft
3:there is a plastic bar that runs across the top of the impeller make sure it is not warped and catching the impeller
