coffeealex Possibly it would briefly reduce the noise….but the bearing is shot…which may have damaged the bottom one as well due to vibration and runout. WD 40 isn’t bearing lubrication and shouldn’t be sprayed into factory sealed and grease lubricated races.
Just replace it. BB had 1 motor, I’d advise you get it, as a restock won’t be that price. I know what the factories in italy pay for those units.
P.S. I think it’s quite likely an Izzo Alex/Duetto motor.