I do't think that I would put any lubricant on a belt or pullie. This
goes doubly for serpintine belts as on some vehicles the smooth side
actually drives some components. I would suggest removing the belt(s)
and cleaning the pullies before installing new belts. For cars using a
standard V-belt you can scuff up the sides of the pulley with sandpaper.
A sure fire check so slipping belts is to look for deposits of rubber on
the fan for the alternator.
John D. Knight III '73 MGB (under restoration)
"If uniqueness makes us who we are, why be like everyone else?"
Yes, I do get the digest version of the list.