What is the noise?

hello. I have an ideal classic boiler which heats the home and the hot water. This morning the boilder was making a load noise high pitched. then the thing stopped working. I could not get the boilder to pilot and start. A friend of my dad is a plumber and sprayed some WD40 on the fan motor whhich has worked but the noise is still there and is fairly loud. Can anything be done? Is it safe? and do i need to buy a new fan? If so where from?

Thanks for your help>>>>