Turns out the hair line cracks are just casting marks. Put the belt back on and it has been running fine The belt could have jumped off because of a heavy uneven load!
Ian
January 2009
I have the same fault. It is easy to remove the back of the machine. My drive belt had come off the pulleys and because it didnt look worn I put it back. It lasted two washes and came off again. On closer inspection two of the arms on the drum pulley have hair line cracks and I'm assuming this will allow the pulley to flex and throw the belt. Watch this space!
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