Hmm... I hit trouble with our dryer again (now solved)...
The fan/pulley started making a terrible din, and I couldn't quieten it, and worse the belt was slipping, so I was concerned that the element might overheat. The problem was that the plastic had worn, and so that the pulley wobbled, jammed and squeaked. My wife located a new fan/pulley at our local appliance services in Eastleigh, and that seems much smoother and our dryer now works and is very quiet.
Replacing this fan unit is much easier than replacing the main belt - you just need to take off the fan/heater cover and unscrew the old one and fit the new one.
One other thing I ought to mention, is that it is possible to fit the main belt incorrectly - I believe it should go over the jockey wheel from the top left (looking from the rear), and it should be in contact with the jockey wheel from about 12 o'clock clockwise to about 4 o'clock. Then it goes under the motor axle, and back around the drum on the right.
I have in the past (incorrectly) managed to reverse the order of the route around jockey wheel and motor axle, such that the belt was very tight and the jockey wheel was hard against the end stop. This damages the belt.
The jockey wheel has a small plastic bush next to it. On our dryer this had become worn to almost nothing. I found a plastic piece from a tap that I used instead. Without this the jockey wheel wanders and the main belt falls off.
I've been pleased with this Zanussi TC470 - I don't mind having to fix worn components now and again - particularly as it is possible to get the spare parts.
BobG, January 2004