Well it has been 8 months since my heater fan fix and 'the noise' came back,now replacement fan and motor top the $500 mark,so once again lay under the RHS dash and removed the seven screws holding the motor/fan unit and removed it. This time I realized that silicon would not fix the problem,so removed the motor cover,just press in the four rubber wedges and then gently slide the cover up.Took a look at where the shaft turns on the end of the electric motor and again NO bearing but a bushing which was dry dry. Decided to drill a hole down the outside of the shaft through the plastic cap,fill that with white grease and inject more grease around the whole shaft.Took a look at removing the fan from the other end but did not seem possible,although at one stage I was contemplating grinding the burred-over end of the shaft,removing the fan that way,then drilling and taping a hole in the ground off end and inserting a screw and washer. Decided to go the easier route and injected white grease all around the shaft where the fan and motor meet. I connected the fan assembly back to power and let the fan run quietly for 10 mins to pull in the white grease which it did so added a little more white grease to both ends of the central shaft.
All is now perfectly quiet and trust that this fix will last longer than the 8 months the just silicon did.I have been told that this is a common occurrence with VW fans across the range of models,so why would they continue to use bushes and not bearings,but then again would not sell as many new 4500 replacement units,silly me!!