I had the same problem with a hotpoint and run a short wash with the machine empty and when the timer knob got to spin cycle it stoped moving I could hear it 'click' but it wouldn't move on. I forwarded it on manualy to spin.If yours does the same it may be the timer is faulty when it gets to the spin point in the wash cycle. That's a job for an engineer i'm afraid.
However some machines have a 'no spin' facility so if your timer knob keeps going then this could be the fault that it's been used and hasn't cancelled. The main reason for this faciltiy is for clothing which has to be washed seperate if the wash instructions on it say 'don't spin' or has the spin symbol crossed through.
bob
October 2005